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A
MANUAL
OF
CHEMICAL ANALYSIS
AS APPLIED TO THE
EXAMINATION OF MEDICINAIi CHEMICALS.
A GUIDE FOR TflE BE'KBfilllNA'aOI? eE-'gpiJl-.IDEJiTlTY AND QUALITY,
AND FOR TlTETJETOflOW OFlMtimi^rESA-NMBULTERATIONS.
FOR THE USE OF
PHARMACISTS, PHYSICIANS, DRUGGISTS, MANUFACTURING
CHEMISTS, AND PHARMACEUTICAL AND
MEDICAL STUDENTS.
THIRD EDITION,
THOROUGHLY KE VISED AND GREATLY ENLARGED.
BY
FREDERICK ^OFFMANX, A.M., Ph.D.,
* PUBLIC ANALTHT TO THB 8TATK OF XEW YORK, ETC,
AND
FREDERICK B. POWER, Ph.D.,
rROFBSftOR OK AXAI.TTICAI. CIIBHIHTRY IX THB PHlI.AnELPHIA COLLBGB OF PUABMACT.
PHILADELPHIA:
HENRY C. LEA'S SOX & CO.
1883.
' ••• ■ "l *■. /■■
• •
• •
•*: ••I
Kut«?n.Ml according to Act of C'ougrosa, iu tlio year 1883, by
HENRY C. LKA'S SON & CO.,
in the Office of the Librarian of Congress. All riglits reserved.
COLLINS, PRINTER.
» This hook is the pro i,.
' ^^^ COOPER MEDICAL COL:.. . •
8AN FRANCISCO. CAL.
and is not to he r^^mord / *r>i f ».
}( 'it.hr "/ y /• ■ .';■ :.■■■■ ■
• PREFACE TO THE THIRD EDITION.
The third edition of this work has been thoroughly revivsed and
I
to a large extent re-written, in order to make it comply with the
present compass of chemical knowledge, as also with the recently
issued new editions of the Pharmacopoeias of the United States of
America and of the German Empire.
The general and original plan and character of the work have
been retained; the first part has been much enlarged, so as to aftbrd
an explicit and comprehensive guide and work of reference to
both student and expert. All the articles of the second part
have been carefully revised and greatly enlarged, many new
ones added, as also the most approved methods for the sepa-
ration, identification, and, in most cases, for the quantitative
estimation of the chemical poisons likely to be met with in foren-
sic research.
As in former editions, the aim has been to render each article
complete in text and illustrations, so as to avoid, as far as possible,
references to other articles. The German, French, and Spanish
names have been added, as also a large number of new illustra-
tions of apparatus and forms of crystals.
The senior author desires to express his obligations and thanks
to his friend and associate Dr. Frederick B. Power, to whose
eificient and able assistance all credit for the superiority of
the present edition is due.
New York, February, 1888.
^I^ hook is thep'i^,
COOPER MEDICAL il
SAN FnANClSCO. CAL.
and isi vot to Ji,» 7., ,,,,. ; .
PREFACE TO THE FIRST AND SECOND EDITIONS.
Although the preparation of most medicinal chemicals has
passed away from the laboratory of the pharmacist, and is sue
cessfully conducted on a commercial scale in manufacturing estab-
lishments, yet the responsibility for the identity and quality of
medicines, and of the substances used in their preparation, rests
properly and legally with those who prepare, compound, and dis-
pense them. It is therefore the duty of the pharmacist and the
dispensing practitioner of medicine, as also, to a considerable
extent, of the druggist and the manufacturing chemist, to examine
the medicinal chemicals of commerce as to their identity, quality,
and purity. In the exercise of this duty, they have frequent
occasion to resort for information to references now widely scat-
tered through chemical, pharmaceutical, and medical manuals and
journals; since our literature, although of vast and increasing
extent, and crystallizing more and more into distinct branches, is
still wanting in a special guide for ready reference in the applica-
tion of chemical analysis to such examinations.
In the present volume I have endeavored to supply this want,
in a manner and to an extent which, it is hoped, will confine the
work within the precise limits of requirement, without detracting
from its general scope and its practical usefuhiess.
Since chemical tests and examinations bear upon and involve
the methods of systematic chemical analysis, and as these cannot
be described in each particular instance, I have deemed it expe-
dient to preface the volume with a few notes on operations and
reagents, and on a few important general tests, and to present a
Vl PREFACE TO THE FIRST AND SECOND EDITIONS.
brief outline of a simple course of qualitative analysis for the sys-
tematic and progressive recognition of such substances as are met
with in the medicinal chemicals. A brief guide has also been
added for the volumetric estimation of those compounds to which
this mode of examination is especially applicable.
Upon these preliminaries is based the subsequent description of
the physical and chemical properties and relations of the medici-
nal chemicals and their preparations, and of the methods em-
ployed for establishing their identity, and for ascertaining their
quality and purity. It has been compiled with special reference
to the recent editions of the Pharmacopccias of the United States,
of Great Britain, and of Germany, and has been brought within
the briefest possible compass, with the view to furnish a concise
and trustworthy guide, combining easy execution, simple appa-
ratus, and economy of time, with the greatest attainable accuracy.
In preparing this compendium, I have consulted, and at times
made free use of, a number of standard works, and periodicals of
the kindred literature. I have, however, felt compelled, not with-
out hesitation, to omit the introduction of references, which would
have required much space, and would have greatly increased the
size of the volume, without affording a corresponding advantage.
Though well aware of the shortcomings and imperfections of
the work, I nevertheless venture to hope that it will meet with
kind consideration, and will prove both serviceable and stimulat-
ing in a province not yet duly appreciated or deservedly culti-
vated. This hope is the stronger, as the work api)ears at a time
when tlie rapid advance of both sciences and arts, the drift of
public sentiment, and the consequently increasing obligations of
the pharmaceutist and the physician, all tend toward higher quali-
fications, and necessitate also, among other attainments, a more
extended exercise of knowledge and skill in chemical and micro-
scopical investigation.
New York, February, 1873.
CONTENTS.
PART FIRST.
Opkrations . • .
Keagknts ....
Rkagknts and Test Solutions
Course of Qualitative Analysis
Prelimiiiary Examination
Solution
Examination for Bases
Examination for Acids
Table of the Deportment of the Compounds of the Principal Metals with
some of the General Reagents
Volumetric Analysis .
Analysis by Neutralization
Estimation of Alkalies
Estimation of Acids
Analysis by Oxidation and Reduction
Estimation of Sugars
Analysis by Precipitation
Alkaloids
PAOB
17
26
29
43
44
48
49
61
69
70
80
80
86
88
96
98
102
PART SECOND.
Acetum
Acidum
n.
MEDICINAL CHEMICALS AND THEIR PREPARATIONS.
Aceticum .......
Arseniosum ......
Detection of Arsenic in Forensic Investigation
Detection of Arsenic in Coloring-matters, Paper, and Fabrics
Benzoicum
Boricum
Carbolicum
Chromicum
Citricum
Gallicum
Hvdriodicum
117
122
126
132
134
135
137
139
142
144
147
148
Tin C0HTB9T8.
rAGB
Acidum UyilufhTrmwum . . . . . .150
•• Ilvdrorhlrjricum
*
lb:\
Hv(ircicviiDk-uni
. 15J*
Dctcrtion of Hvdrocvjinic Aci
li in Forunwc Invc«tiga
tioo
. 161
•• IIyfjophoffphoro«um
> • •
. 163
** Liu-tu'um .
164
•• Nitrimm .
. 165
Oleii'um
. 171
** OxAlicum .
. 172
'• Phf>f(phoricMim
. 174
Salicylicuni
. 181
•* Swx'inicuni
. 182
** Sulphururum
. 184
** Siilphuroflurn
19<»
** Tunniitim ....
192
Turtaricuin
. 19,5
** ValeriMnicum
. 197
Ai^oiiitina .....
. 200
^:tlMT .....
. 201
Althvr Avi'X'u-un ....
. 204
AK'ohol .....
. 2<»6
Alcohol Anivlk'um
*
. 210
Aloiniim .....
. 211
Aluinrn ....
. 212
l)vU'ri\im of Alum in Flour and Hreai
. 214
Aluminii Hydnui
. 214
** iSiilphan
. 216
Aninionii Himzoan .
. 217
** Hromidum
. 217
** CarbonaH
221
(Miloridnm
. 223
Io«lidum ....
. 225
*' Xitrafl ....
. 226
I'li(K4phaii
227
*• Sulphart ....
228
*• ValerianAK
229
Amvl Nitris ....
•
28(»
Antinionii ct rotaxNii TartniM
. 2.S2
'* Oxiduin
2.35
'' Sulpliidum
237
** ** Aiinmtianini
240
Antinionium Stilphiinituni .
242
Ap«)mor|i1iiiui> II v<Ir(M>liloni;4
245
A({ua AnniioniiL* ....
245
'* Anivjrduln' Amaru* .
249
'• Chloii ....
251
•* DiMtillata ....
254
CONTENTS.
IX
PAOB
Argcnti Cyiinidum ........ 256
'^ lodidum
9 *
. 257
'» Nitraa
»
• 258
*^ Oxidum
•
. 2G1
Arsenii Bromidum .
t
. 262
** lodidum
. 263
Atropina
• i
. 263
Atropinae Sulphu8 . *
. 265
Auri et Sodii Chloridum
9
. 266
Barii Chloridum
I 1
. 26 ft
Benzinum .
B
. 269
Bismuthi Citras
t *
. 270
** et Ammonii Citra
4
»
. 272
*' Subcarbonas
1 «
. 273
** Subnitras
■
. 276
'* Valerianas
. 277
Bromum
«
. 279
Bnicina
«
. 282
Cadmii lodidum
ft
. 284
** Sulphas
. 285
Cafietna
•
. 286
Cak'ii Bromidum
1
. 287
** Carbonas pnucripitatu.
«
1
. 289
'* Chloridum .
1
. 290
** Hypophosphin
■
292
*' loilidum
•
293
" Phosphas pra;(M)>itatu
s
. 294
Calx Chlorata
■
296
** Sulphurata
. 299
Camphora monobroniata
»
. ^00
(-antharidinum
•
. 300
Carbonei Bisulphidum
301
C<*rii Oxalas
*
;J03
('hinoidiimm
«
304
Chloral
m
305
Chloralum Butvlicuiii
•
308
(*hlorofbrmum
•
308
Chrysarobinum
a
312
Cinchonidina
•
313
Cinchonidinttf Sulphas
•
314
Cinchoiiimi
315
Cim^honina; Sulplins
•
317
Codeina
■
318
Colchicina .
1
i
320
CoDiiiia
322
(.'reasotuui .
324
i'Upri Aeiftas
. 326
CONTENTS.
Cupri Oxiiluro
" Sulphas
Cuprum Ammon latum
CurarinH
Digitalinum
Elateriimm
Emctinn
Ferri ArseniuB
" Curbonas SacchiirnluH
" Chloridum .
" Citras
" ct Ammonii Chloriilum
•* ■' " Siilphiis .
" '• " Tartras .
" " PoUMiiTumw .
** " 4j»ii,ii.»Citr.,. .
" " Strj'fhnina) Citriiii
" Ferroej-oniiium
" Hypojihospliii
*' lodidum
" Oxaliis
" Oxiduro Hydratum .
" Phoaplias
" Pyropliosphas
" Sulx'Hrbonas
" Sulpha.'
" Vak-rianns
Femira
GlyL-crinum
IX-tcctioD and
Hydrargjri Chloridum
Imlidum nibrum
Oxidum Havuni
' ■ nibnini
Siibnitras
Subsulphan Havus
Sulphliluni rubrum
Hyoscyamina- Sulphu
lodofonnum
CONTENTS.
XI
(i
(I
(k
44
i*
4k
4 »
44
44
44
44
44
44
lodum
Liquor Ammonii Acetatis
Antimonii Chloridi
Calcis
FeiTi Acetatis
** Chloridi
** Citratis
** et Quininsp C
** Nitratis
'* Sulphatis
Hydrargyri Nitratis
Pliimbi Subacetatis
Potasstc
Potassii Arsenitis
Sodse
** Chloratflp
Lithii Bonzoau
** Bromidum
'* Carbonas
** Citras
** Salic V las
Magnesia
Magnesii Carbonas .
Sulphas .
Sulphis
Mangani Oxidum nigrum
** Sulphas
Morphina .
MorphinHB Acetas .
Morphinai HydrochlonLs
Sulphas .
Morphionietric Assay
44
41
44
44
4 4
Kicotina
Oleum Amygdala? a^thereui
** Sinapis a^thereum
Phosphorus .
** Detection of phosphoru
Physostigminje Salicylas
Picrotoxinuni
Pilocarpina; Hydrochloras
Piperina
Plumbi Acetas
** Carbonas .
** lodidum
** Nitras
** Oxidum
tratis
of Opium
Tincture of
in fore
Opiuu
nsic inv
stigutioii
PAHK
393
397
897
399
899
401
402
403
404
40ri
406
407
408
410
412
414
4ir>
41(>
417
419
420
421
422
423
426
426
429
43(»
482
433
434
435
439
439
44(»
443
445
446
449
449
451
451
452
453
455
456
457
xu
CONTENTS.
i(
»t
ti
»t
(C
4»
t (
*i
4»
(k
i(
44
» 4
Pluinbi Oxiduin nihrum
Potoysa Sulphurata .
PotHHsii Acetas
** BicarbonH.s
Bichrotuas .
Bitartnu)
Broiniduin .
Carbonas Criidus
** DopuratuM
** Punis
Chloras
Citras
Cvaiii(]uni .
et Sodii Tartnt'*
Ferrocyaniduin
Hydras
•' cnHliis
Ilypopliospliis
lodidum
Nitras
PermaugaiiaH
Sulphas
Sulphis
Tartras
Quiiiidina .
Quinidinw Sulphas .
Quinina
^' estimation ot'the alkaloids iu Cinchona bark
Quininie Hydrobromas
Bisulphas .
Hydrorhloras
Sulphas
Tannas
Valerianas
Resorc'inuni .
Salicinum .
Santoninum
Sodii Acetas
** Arsenias
Henzoas
Bicarbonas
Bisulphis
Boras .
Bromidum
Carbonas
Chloras
Chloridum
4 •
4k
<t
44
44
k4
4 4
• 4
44
44
44
44
44
44
PAOB
458
459
460
462
464
465
467
470
473
475
478
47J)
481
483
485
486
488
490
491
494
497
498
499
501
502
503
505
507
515
516
518
520
523
525
526
527
528
530
532
533
534
537
538
539
543
546
548
CONTENTS.
Xlll
PAOB
Sodii Hydras ........ 550
** Hypophosphis
. 552
** Hypo^ulphis .
. 554
** lodidum
. 556
'* NitraB
. 560
** Phosphas
. 561
** Pyrophosphas
. .564
*' Salic vlas
. 565
** Santoninas
. 566
*' Sulphas .
. 567
»* Sulphis
. 569
** Sulphoearbolas
. 570
Spirltus iSthcris uitrosi
. 571
Strvchnina ....
•
. 574
Strychnina; Nitra« .
. 576
** Sulphas
. 578
Sulphur Pra*eipitatum
. 578
** Sublimatum
. 581
Sulphuris Iodi<luin .
• 583
Thvmol
. 583
ViTatrina .
. 584
Zinci Aceta.<«
. 586
(
* Bromidum
. 587
<
* Carbonas Prex'ipitatus
. 588
(
* Chloridum
. 589
i
* lodidum
. 590
i
* Oxidum
. 591
i
'* Phosphidum .
. 598
'* Sulphas
. 594
^* Sulphoearbolas
. 597
** Valerianas
. 598
Table of Elementary Bodies, with their Symbols and Atomic Weights . 608
Table of Thcrmometric Kijuivalents, aeeordinjr to tlie Centigrade and
Fahrenheit Scales ....... 604
Table for converting Metric MejLsures of Capacity into I'nited States Fluid
Measures ........ 606
Table for converting Uniteil States Fluid Measures into Metric Measures of
Capacity . . . . . . . .607
Table for converting Metric Weights into Troy Weights . . . 608
Table for converting Troy Weights into Metric Weight^; . . . 609
Index
. 611
■ ' . "-V
k ** •
» 1 X
This hook is the p^'^i^
COOPER MEDICAL CO:.... . ,
SAN FRANCISCO. CAL.
iXTiff 7S not ^* fi^' 7V '///»• d >* t-^ / ^ ^
LlJjnti )t I.'- ■ < f / < ,.; or
PART I.
OPERATIONS AND REAGENTS,
INCLUDING AN OUTLINK OF
A SYSTEMATIC COURSE OF QUALITATIVE CHEMICAL ANALYSIS,
VOLUMETRIC ESTIMATION,
A5D A
METHOD FOR THE SEPARATION AND RECOaNITION
OF
THE PRINCIPAL ALKALOIDS AND ALLIED PRINCIPLES.
. .M
7%is hooh is the pro pi ,
COOPER MEDICAL CO; J.:.....
SAN FRANCISCO. CAL.
«W ^s not to lie rf'Mor^d ^'"fm t\^
• I
OPERATIONS AND REAGENTS.
OPERATIONS.
The operations involved in the application of simple tests and
chemical examinations must be supposed to be familiar to the
pharmacist, the druggist, the pharmaceutical or chemical manu-
facturer, and the physician. For the student and the less experi-
enced operator, however, the following preliminary explanations
and descriptions relating to the more important simple operations
are considered to be of sufficient practical value to merit a brief
notice.
Solutions. — With regard to the nature of the product, two kinds
of solution are distinguished, simple and chemical. In a "simple
solution" the dissolved body retains all of its original properties,
with the exception of its physical form, and may be obtained
again in its former state on the removal of the solvent by evapo-
ration : for instance, solution of ferrous sulphate in water. It
is "saturated" when the solvent ceases to take up any more of
the dissolved body; but as the coefficient of solubility of most
substances is increased by heat, the expression of saturation will
therefore always relate to the temperature at which the solution
has been formed. A "chemical solution" is one in which the dis-
solved body no longer retains its original qualities, but, through
the action of the solvent, has become converted into a new sub-
stance, possessing variously modified chemical and physical prop-
erties: for instance, solution of ferrous carbonate in dilute sulpliuric
acid.
Solutions for testing are best prepared in test-tubes, or in small
flasks or beaker-glasses.
Increase of the surfaces of contact by comminution, agitation,
and increase of temperature, as is well known, aid and accelerate
the process of solution, as well as of chemical reaction ; and one or
both of these auxiliaries may be employed, unless the nature of
the substance or the effect of heat upon it is such as to exclude
their application.
The common solvent, water, has to be used distilled, and this
fact is to be understood throughout this work ; neither rain-water
nor spring-water, however pure it may appear to be, can be used
18 MANUAL OF CHEMICAL ANALYSIS.
indiscriminately as a solvent or for edulcoration in chemical in-
vestigations.
To effect the solution of substances insoluble in water, for the
purpose of chemical examination, or where the aid of an acid is
required, only such acids as are found by the operator himself to
be chemically pure should be employed.
Precipitation. — The formation of an insoluble body from a solu-
tion can be effected either by a change or modification of the
solvent, or by the production of one or more new bodies, insoluble
in the solvent. An instance of the first case is an aqueous solution
of barium chloride, which will be precipitated by the addition of
concentrated hydrochloric acid, or a solution of calcium sulphate,
which will be precipitated by alcohol ; in both these instances the
solvent power of the liquid is lessened, and solution may be re-
established by the addition of a sufficient quantity of water. In-
stances of the second case of precipitation are a solution of calcium
hydrate precipitated by sodium carbonate, and a solution of mag-
nesium sulphate precipitated by barium hydrate.
Precipitation is resorted to as the most important mode of de-
tecting and discriminating bodies by tlieir physical and chemical
properties, and of effecting their separation. According to the
nature or appearance of the precipitates, they are variously dis-
tinguished; thus ** flocculent," when forming flock-like masses;
"crystalline," if, when magnified, the small particles are seen to
be composed of minute but distinctly formed crystals; "gelatinous,"
if jelly-like; or "curdy," if separating in the form of a curd, etc.
The terms "turbidity" and "cloudiness" designate the formation
of a precipitate so insignificant in quantity, or so finely divided, or
so light in weight, that the suspended particles only impair the
transparency of the fluid, and require a certain amount of time
to subside in the form of a precipitate. If tlie transparency of a
colorless or nearly colorless liquid becomes so sliglitly impaired
upon the addition of a reagent as not to become distinctly turbid,
but displays a reflection of pearly light, and thus presents an
opal-like appearance, the minute degree of precipitation thus
produced is designated as "opalescence."
Filtration and Decantation. — The separation of the supernatant
liquid from a precipitate is effected either by filtration and subse-
quent washing of the precipitate upon the filter by means of
a wash-bottle (Figs. 1 and 2), or, where the precipitate speedily
and completely subsides, by decantation. As a rule, funnels and
filters must be small, and proportionate to the amount of the pre-
cipitate and the liquid requiring filtration.
Filters employed in analytical operations should be as free as
j)ossible from inorganic substances, tspecially such as become dis-
solved bv the action of acids, as calcium salts, ferric oxide, etc.,
and for the collection of precipitates should be smooth, so placed
in the funnel as to fit closely on all sides, and cut so as not to
OPERATIONS.
project over the rim ; it is also advisable always to moisten the filter
upon the funnel willi distilled water, by means of the wash-bottle,
previous to the collection of the precipitate, or to filtration.
Decantalion is effected either by pouring oft' the supernatant
oloar part of the fluid by simply inclining the vessel, and allowing
the fluid to flow Jown a glass timI (Fig, 3), or by drawing it off
by means of a smull glass siphon or a jiipette (Figs, i and 5).
Washing PreclpitateB.^ — lu either mode of separation the precipi-
tate, in most instances, must be thoroughly freed from the ad- ,
dering liquid by washing with water, either on the filter or by
deoantation. As a rule, the washing of precipitates is most
thoroughly and quickly effected by means of hot water ; for thia
purpose nothing more is required than the ordinary wash-bottle,
MICAL ANALYSIS.
wliiuli, however, for oonvKnience in holding, is provided either
with a wooden handle, attached by metins of a strong wire to ihe
flask (Fig. 2), or the neck of the flask mav be covered with a
thick circular atrip of cork, or tightly bound with twine.
In order to ascertain whether a precipitate has been sufficiently
or thoroagldy washed, a few drops of the liquid, as il escapes
from the funnel, may be collected from time to time on platinum
foil, and subsequently slowly evaporated, whereby the presence
of soluble, non-volatile bodies will be indicated by a visible resi-
due. In some cases, and particularly wJiere the bodies to be
removed by washing are of a volatile nature, the completion of
the operation may be most quickly determined by the application
of chemical tests; thus, if the liquid in which the precipitate
has been produced contains a sulphate or chloride, the complete
ret4oval of these salts will be indicated by testing a few drops
of the filterpd liquid with barium chloride or argentic nitrate,
whilst if the liquid contain free acid, or a volatile alkali, such as
ammonia, their complete displacement may be determined by
means of litmus.
Remorii^ PreoipitateB from tbe FUter.—When a small quantity
of a moist precipitate has to be taken from the filter for further
examination, this is best done by carefully dipping the end of a
thin glass rod into it, and subsequently detaching the adherent
part of the precipitate upon a watch-glass, the interior of a small
test-tube, or the microscopic glass slide.
If a precipitate is to be removed from the filler as completely as
possible, this maybe accomplished either by puncturing the point
of the filter by means of a glass rod, and subsequently washing the
precipitate with a fine stream of water or other liquid from a
wash-bottle into a receptacle beneath, or the funnel may be held
in a horizontal {wsitiuu, so that its rim projects inside the edge of
OPERATtONS. 21
a poroelain dish or beaker, when by directing a fine stream of water
against the sides of the filter by means of a wash-bottle, the pre-
cipitate may be removed without brealcing the filter.
If, however, it is not desirable lo add a liquid to the precipi-
tate, the filter with ita contents is first allowed to drain thoroughly
in the funnel, and is then opened and placed npon a glass plate
or upon several layers of bibulous paper, when the moisture
will liave soon become snffiuicnlly abaorlied to permit the ready
removal of the precipitate with a glass rod or a spatula. When
it is desired to dissolve a precipitate on the filter, the solvent
should, when ailraissible, be first heateil, and gradually poured
upon the precipitate, and the filtrate, which will contain the pre-
cipitate in solution, collected in a test-tube or beaker; if the pro-
oipitato does not thus become completely dissolved, the filtrate is
again heated, and returned to the filter until complete solution is
eflecled, which may be finally aided, if necessary, by the addition
of a fresh portion of the solvent. If the precipitate should be
considerable in amount, the larger portion may be first removed
by means of a spatula, and transferred to a porcelain dish or
beaker, and the residue upon the filler subsequently dissolved by
the aid of the proper solvent.
Drying Precipitates — When a precipitate is required in a dry
condition, it is first iillowed to drain as completely as possible on
the filter, and lite funnel and tiller are then placed in a hollow tin
cone or I'ylinder (Fig. 0), which is supported on a piece of wire
Sauze over a moderate gas fiame, being careful to so regulate the
eat as not to char the filter. The operation may also be accom-
plished still more quickly by opening the filter and spreading it
with its contents upon a. porcelain plate or watch-glass, which is
placed upon a piece of wire gauze over a low (lame, the proper
precautions being observed to prevent excessive heat. In either
«, the precipitate mav be first partially dried by opening tlte
filter, and placing it with its cuiiteuts a\wn several folds of bibu-
lous paper.
In tbe more exact requirements of analysis, tbe preuipiliiie or
otlier aubstacce requiring desiocsitioa may be placed under a bell-
jiir containing concentrated sulphuric acid or fragments of fused
calcium chloride (Fig. 7), or in an air-bath or drying oven, pro-
vided tt'iih a thermometer, and the tcmperulure of whicli is
regulated by a gas flnmo {Fig. 8). By this means a uniform
tem[>crature may be readily maintained, which may be varied
in accorihincc with special reijuiremcnls.
WeigMl^ Precipitates.— Before ascertaining the weight of a pre-
cipitate, it is usually required to be first completely dried at a defi-
nite temperature. This is accomplished by means of the above
illnstraled air-bath. The precipitate, after partial drying upon the
filter in the funnel, is placed upon a wntch-glasn. which, together
with another glass of the same eize and a small brass clamp, has
been pi-evioualy accurately weighed. During the process of dry-
ing the glft».=es are placed one within the
P'" "■ other, so that the moisture from the
precipitate contained on the upjiermost
glass may readily escape. When the
precipitate has become siifficieutly dry,
it is removed from the nir-bath, the lower
watch-glass placed ufvin the upper, and
the whole secured by means of the brass
OPIiRAT[0!tS
23
clamp (Pig. 9), in order that on cooling no moisture shall be ab-
sorbed by exposure to the air. The glasses, with the inclosed
precipitate, as indicated in the figure, are brought upon the
balance, and the weight finally determined. In order to assertaiii
that no further loss takes place upon drying, the glasses are again
opened, placed in the air-bath aa before, and the operation re-
peated until two successive weighings prove the weight to remain
constant.
Ignition. — The process of ignition refers to the subjection of
solids to a more or less elevated temperature, and is employed
for various purposes, but has, usually, for its object, the separa-
tion of a volatile from a leas volatile or non-volatile body, when
the latter alone is required; it is aIbo frequently employed for
oscertairiiug the eifect of strong heat upon a substance. In the
latter case the substance is heated in a bent glass tube (Fig. 10),
whereby the nature of the evolved gases or sublimate prtiduced
may be observed, whereas, if it be required simply to ascertain
or confirm the volatile or non-volatile nature of a substance, it
is heated on platinum foil, in the non-luminous flame. For the
ignition of precipitates, however, the substance is placed in a
porcelain or platinum' crucible of convenient size (Fig. 11), sup-
Fio. 10. F:o, U.
ported on a wire triangle, and heated in the non-luminous gas
flame, or, if a higher temperature be required, by means of the
blowpipe or gas blast-lamp.
Determination of the Melting and Boiling Point.— The melting
and boiling point of bodies under normal atmospheric pressure
t Tlie use of plaliaum veBsela sliniUil Ihj avoided for lieatins! sulwtaiicfis wliicli
develop cblorine, the »lk«ltne UyJratea, nitrates, and cynnitlcs. melnllic sul-
pliidea. readiiy n-ducible metallic oxides, salts of tlie heavy luelala with orgaaic
kclds, or phosphates in ttiu presence of organic compounds.
8
MANUAL OF CHEMICAL ASALTStS.
being contant snd unchangeable, the deter mi nation
of these factors is an operation which is frequently
resorted to for the purpose of establishing the iden-
tity of a substance, and for aflbrding confirmatory
evidence of its purity.
The meUin'j point ia determined by bringing a
very small jmrtion of the substance into the lower
part of a capillary glass-tube (Fig. 12), and attaching
the latter by means of a small rubber band to a
thermomeler, so that the snbalance will be on the
same level and in the moat direct possible contact
with the thermometer bulb (Fig. 13). The ther-
mometer, thus arranged, is then suspended, and the
bulb and the capillary portion of tlie tube allowed to
dip below the surface of water or sulphuric acid, contained in a
beaker; the liquid employed being adapted to the melting poJat
of tho substance. The liquid is theu very gradually healed by
means of a carefully regulated gas Hame {Fiff. li), and the moment
when the body melta in the capillary tube ia accurately observed
and the temperature noted.
The boiling point ia determined by bringing the liquid into a
vessel adapted for fractional distillation (Fig. 15), or into an ordi-
nary glass flask provided with a doubly perforated cork (Fig, 16),
Fio. 15. Fib. 18.
in one orifice of which the thermometer is inserted, while the
other is provided with a bent glass tube, which may be connected
with a condeneer. The thermometer should not be allowed lo
become immersed in the liquid, but should simply project so
far into the interior of the t9ask
as to be surrounded by the vapor F'o. n.
of the boiling liquid. On the appli-
cation of heat, the boiling t>oint
will be indicated by the height of
the mercurial column when the
liquid is in a state of active ebulli-
tion.
Bending of 01a» Tabing — Glass
tubing may ha regularly and uni-
formly' buut in any demred shape
26 MANUAL OF CHEMICAL ANALYSIS.
bv the use of the upper edge of the common fish-tail gas-flame; the
flame of the Bunsen gas-lamp cannot be well employed, producing
unsatisfactory curves. The tube is held in a horizontal position in
the flame at the point requiring to be bent, so that it becomes
entirely enveloped by the illuminating portion ; it soon becomes
covered with a deposit of soot, and, when sufficiently heated, bends
itself by the weight of the unsupported end (Fig. 17). The bend, if
properly made, will form a symmetrical curve, without diminish-
ing the calibre of the tube at any point, and will be free from
sharp angles. Glass tubing or rods when employed in analytical
or chemical operations should have no sharp or protruding edges,
but should be made smooth and round by holding the ends for a
few seconds in the non-luminous gas-flame.
REAGENTS.
The methods of chemical analysis and investigation consist in
brint<in<^ the substances under examination into contact with
other bodies of known properties, and observing the resulting
phenomena. These phenomena consist in alterations, either in
8tate of aggregation, form, or color, resulting from some chemical
change. All bodies which are employed for this purpose are
called reat/ents, and the ensuing phenomena reactions.
It is obvious, therefore, that a sufficient knowledge of theo-
retical chemistry in its details, and especially a familiarity with
the deportment, properties, and relations of the common com-
pounds and reagents, are indispensable to the pursuit of chemical
tests and examinations. Upon such knowledge depend the con-
ception and comprehension of the conditions necessary for the
formation of new compounds, and for the manifestation of the
various reactions, as well as the correct inference from the obser-
vations and results of all investigations; and without it they will
remain unavailing and uncertain.
No special and definite rules can be assigned for the applica-
tion of reagents in each instance, with respect to their proportion
and quantity. These must depend upon the quantity and nature
of the substance under examination and its solution, as well as
upon the nature of the reagent, the strength of its solution, and
the processes taking place in each particular reaction. Knowl-
edge and reflection, as well as a ready comprehension of the
object and aim of each test, of its issues, and of the possible inci-
dents, and a correct inference from all phenomena, must decide
at large, as well as in detail, not only what reagents should be
employed, but also the amount and the conditions in each par-
ticular instance.
The general method for ascertaining the sufficient or slightly
RBAQBNTS. 27
excessive amount of a reagent, as has to be done before proceeding
in the systematic course of analysis, is to add a few drops more of
the reagent to the clear liquid obtained either by allowing the
precipitate to subside, or by filtering off a small quantity of it ; if
any further precipitate is formed, the filtered portion must be re-
turned, more of the reagent added, and the clear liquid again
examined with a few additional drops of the reagent, until no
further precipitate is produced. With some reagents, as, for in-
stance, with hydrogen sulphide or ammonia water, this method
of procedure is rendered unnecessary, an excess being indicated
by their characteristic odor.
A common error, and an obstacle to the less skilled, is the use
of an undue excess of reagents. There are reagents which in
many cases admit a free application without disadvantage to the
correctness of the result — as, for instance, hydrogen sulphide,
solution of calcium hydrate, etc. ; but the majority of reagents
need to be applied in common tests only by a few drops of their
solutions — as, for instance, baric, ferric, cupric, and argentic solu-
tions, etc. On the other hand, there are not unfrequently errors
arising from an insufficient amount in the application of reagents,
especially with dilute solutions, or in those cases in which the
complete elimination of a substance by precipitation is required
for the subsequent examination for other bodies: for instance,
hydrogen sulphide, applied in a limited quantity, produces a
white precipitate with solutions of mercuric salts; applied in
excess, it gives a black precipitate. There are other instances
where an excess of the solution under consideration, as well as of
the reagent, may redissolve, and consequently destroy, the pre-
cipitate whereon the reaction is based.
In operations of chemical analysis it must always be borne in
mind and well understood that, in the processes and phenomena
taking place between the reagents and the substances act d upon,
as in all chemical changes and reactions, certain laws and definite
limits exist between cause and effect, and that the ability of cor-
rectly applying knowledge, judgment, and skill, and of drawing
the right inference from necessary as well as from casual reactions
and phenomena, must rule and guide the methods and operations
of the investigator, and carry them beyond mere conjecture and
empiricism.
It is beyond the scope of this work to describe the mode of
preparing the reagents, their use and application, and their deport-
ment with the common compounds, or to dwell upon the general
rules of systematic methods, accuracy, order, neatness, and clean-
liness to be observed in the execution of analytical work. For
such information reference must be had to the text-books of
applied and analytical chemistry. From a practical point of view,
only the usual strength of the solution of the reagents, as best
suited for the common tests and examinations, and the mode of
28 MANUAL OF CHEMICAL ANALYSIS.
preparing a few of the rarer or special reagents, or of such as are
not included among the medicinal chemicals considered in this
volume, have been stated.
As regards the strength of the solutions of reagents, unless
otherwise stated, the test solutions described upon the following
pages are invariably understood to be used wherever the name of
the reagent only is stated.
It hardlv needs to be mentioned that all rea^cents must consist
purely of their essential constituents, and must contain no admix-
ture of any other substance ; it must, therefore, be an invariable
rule to test the purity of the reagents before they are employed.
The reagents and their solutions must be preserved according
to their nature ; of those whose solutions are liable to alteration
or decomposition only small quantities must be kept, and always
in tightly closed glass-stoppered bottles.
BEAOBNTS AMD TEST 80LDTI0NB.
REAGENTS AND TEST SOLUTIONS.
Fio. 18.
Aoetio Aold Spec. grav. 1.048.
Acetic Add, Diluted. — Obtained by mixing 1 part of acetic acid
with i parts of water,
HydroobloriO Aold. — Spec. grav. 1.16; contaiuing 32.2 per cent,
of absolute acid.
Hydrochloric Acid, Diluted. — Spec. grav. 1.049; containing
about 10 per cent, of absolute acid. Obtaiued by mixing 6 parts
of hydrochloric acid with 13 parts of
water.
HT^OSolpllIirlo Acid. See Hydrogen
Sulphide.
nitric Add. — Spec. grav. 1.42; con-
taining 69.4 per cent, of absolute acid.
When concentrated acids are applied
in small tests only bv the drop, as, for
instance, in testing alkaloids, etc., they
are taken from the bottle by dipping a
glass rod into tlie acid and allowing the
drop or drops to fall upon the substance
to be acted upon, or better by means of
a kind of pijiette consisting of a thin,
strong glass tube, adjusted at one end
to a small caoutchouc bulb, and con-
tracted at the other extremity to a capil-
lary end. The fluid is drawn into the
tube, and delivered again by gentle
pressure of the bulb (Fig. 18).
Nitric Add, Diluted. — Spec. grav. 1.059; containing 10 per
cent, of absolute acid. Obtained by mixing 1 part of nitric acid
with 6 parts of water.
Nitrc-hydroohlorlo Add {Aqua Regia). — 4 parts by weight of
nitric acid, Ppec. grav, 1.42, are gradually added to 15 parts by
weight of hydrochloric acid, spec, grav. 1.160, in a capacious, open
glasw vessel, and, when eftervesceiice has ceased, the product is
transferred to glass-stoi)i)ered bottles, which should be not more
than half filled, and preserved in a cool j)!ace.
Oxalic Add. — Sohition of 1 part of crystallized oxalic acid in
10 parts of water.
Fiorio Acid. — Saturated aqueous solution of picric acid.
MUAL OF CBBHICAL ANALVSIt
In diluting concentrflted eiilphuric acid with water, the acid
slioiilil invariably and graduallj' be added to the water, and in
vesacls which are either placed in cold water or which are not
liable to crack from the heat evolved.
Snlphurip Acid, Diluted. — Spec. grav. 1.068: containing about
10 per cent, of absolute acid. Obtaiued by mixing 1 part of con-
centrated acid with fl parts of water.
SnlphnionB Acid, — Spec. grav. I,0i6. An aqueous solution of
sulphurous acid gas, saturated at 15" C. (oil" V.), containing 3ti
limes its volume, or about 9.5 per cent, by weight of the gas.
Tannio A.oid.— Solution of 1 part of tannic acid in a mixture
consisting of 18 parts of water and 2 parts of alcohol,
Tartario Acid. — Solution of 1 part of crystallized tartaric acid in
5 parts of water.
Albtunen. — The white of one egg is triturated with 100 cubic
centimeteraof water, and is then filtered through cotton previously
moistened with water
Alcohol. — Six'c. grav. 0.820; containing 91 per cent, by weight
or 94 per cent, by volume of absolute alcohol.
Alcobol, Absoliite.— Spec. grav. O.T05.
Alcohol, Amylio — Spec. grav. 0.816 to 0.818.
Alnminluii]. — Metallic aluminium in the form of wire or ribbon.
Ammonia Water (Aipia AmmoniiB).~Spec. grav. 0.959. An
aqueous solution of ammonia, containing 10 per cent, by weight
of the gas.
RBAOBNTS AND TEST SOLUTIONS. 31
Ammonia Water, Stronger (Aqua Ammoniae Fortior, U. S. P.).
— Spec. grav. 0.900. A nearly saturated aqueous solution of
ammonia, containing 28 per cent, by weight of the gas.
Ammoninm Carbonate. — Solution of 1 part of uneffloresced am-
monium carbonate in a mixture of 4 parts of water and 1 part of
ammonia water.
Ammoninm Chloride. — Solution of 1 part of crystallized ammo-
nium chloride in 10 parts of water.
Ammoninm Holybdate.
Ammminm Holybdate in Nitric Acid. — Solution of 1 part of
ammonium molybdate in 10 parts of water, to which 10 parts of
nitric acid, spec. erav. 1.2, are subsequently added.
Ammoninm Ouiate. — Solution of 1 part of crystallized ammo-
nium oxalate in 20 parts of water.
Ammoninm Phosphate. — Solution of 1 part of ammonium phos-
phate in 15 parts of water.
Ammminm Snlphide. — A solution of ammonium sulphide in
water; it is obtained by saturating, at 15® C. (59® F.) or a lower
temperature, 3 parts of Aqua Ammoniac Fortior, U. S. P., with
hydrogen sulphide gas, and by subsequent addition of 2 parts of
ammonia water. It is best preserved in small vials, tightly corked,
and in a cool place. This solution, being concentrated, has to be
employed, in the common tests, only in small quantities, mostly
by drops.
When hydrogen sulphide is at hand, ammonium sulphide may,
in many of its applications, be produceil by saturating the liquid
under examination with the gas, and by the subsequent addition
of ammonia water; or, in ammoniated solutions, if dilution does
not interfere with the reaction, by the addition of an aqueous solu-
tion of hydrogen sulphide.
AniliiiA Snlphate. — Solution of 5 drops of aniline in 25 cubic
centimeters of diluted sulphuric acid.
Argentic Nitrate. — Solution of 1 part of crystallized argentic
nitrate in 20 parts of water.
Argentic Hitratei Ammoniated. — Solution ]>repared by adding
ammonia water, spec. grav. 0.959, in drops, to test-solution of
argentic nitrate, until the precipitate at first formed is very nearly
all redissolved, and filtering.
Argentio Snlphate. — Solution of 1 part of argentic sulphate in
250 parts of water.
Anric Chloride. — Solution of 1 part of auric chloride in 20 parts
of water.
Barinm Chloride. — Solution of 1 part of crystallized barium
chloride in 10 parts of water.
Barinm Hydrate (Baryta- water).— Saturated aqueous solution
of barium hydrate, containing about 5 |)er cent, of the hydrate.
Barinm Nitrate. — Solution of 1 part of crystallized barium
nitrate in 20 parts of water.
32 MANUAL OF CHEMICAL ANALYSIS.
Benzin (Petroleum Benzin or Petroleum Ether). — Spec. grav.
from 0.670 to 0.675, and boiling at 50 to 60° C. (122 to 140° F.).
Benzol. — Spec. grav. 0.885.
Borax.
Bromine Water. — A saturated solution of bromine in water.
Calcium Chloride. — Solution of 1 part of pure crystallized cal-
cium chloride in 10 parts of water.
Calcium Hydrate (Lime-water). — Saturated aqueous solution of
calcium hydrate.
Calcium Sulphate. — Saturated aqueous solution of calcium sul-
phate, containing about 0.2 per cent, of the salt.
Carbon Bisulphide.— Spec. grav. 1.272.
Chlorine Water. — A saturated aqueous solution of chlorine, con-
taining about 0.4 per cent, by weiglit of the gas. For analytical
use, this solution is best preserved in small vials, tightly corked
and sealed, in a cool place, and protected from the light.
Chloroform. — Spec. grav. 1.480.
Cobaltous Nitrate. — Solution of 1 part of cobaltous nitrate in
10 parts of water.
Copper. — Metallic copper in slender wire, or thin foil cut into
strips.
Cupric Sulphate. — Solution of 1 part of crystallized cupric sul-
phate in 10 parts of water.
Cupric Sulphate, Ammoniated.—- Solution ])repared by adding
ammonia water, spec. grav. 0.959, in drops, to test solution of cupric
sulphate, until the precipitate at first formed is very nearly all re-
dissolved, and filtering.
Cupric Tartrate, Alkaline Solution of, (Fehling's Solution). —
17.82 grams (267.3 grains) of pure crystallized cupric sulphate arc
dissolved in 100 cubic centimeters (about 3 fluidounces) of water ;
and 85 grams (2 ounces and 457 grains) of pure crystallized potas-
sium and sodium tartrate are dissolved in 300 cubic centimeters
(about 10 fluidounces) of a 10 per cent, solution of sodium hydrate.
The cupric solution is then gradually added to the alkaline solu-
tion, and, having been well mixed, so much water is added as to
make the whole measure 500 cubic centimeters (16 fluidounces).
The solution should be free from yellowish brown sediment, and
should deposit none upon boiling.
Ether. — Spec. grav. 0.750.
Ferric Chloride. — Solution of 1 part of ferric chloride in 10
parts water.
Ferric Dinitrosulphide. — Obtained by adding, drop by drop, a
solution of ferric chloride or sulphate, with constant stirring, to a
mixture consisting of equal parts of strong solutions of potassium
nitrate and ammonium sulphide, heating the liquid to boiling for
a few minutes, and filtering while hot from the sulphur. The
deep-colored liquid deposits, on cooling, black, needle-shaped
rhombic prisms of ferric dinitrosulphide; these are dissolved 1
part in 10 parts of water, to give the required solution.
REAGENTS AND TEST SOLUTIONS. 83
Ferrous Sulphate. — Solution of 1 part of ferrous sulphate, ob-
tained by precipitation with alcohol, in 10 parts of water.
Ferrous sulphate is best obtained by pouring an aqueous solu-
tion of freshly prepared crystallized ferrous sulphate, saturated at
the boiling-point, into strong alcohol, collecting the precipitate
upon a filter, washing with a little alcohol, drying by pressing
between filtering-paper, and by immediately tilling the humid salt
into small warm vials, which are corked and sealed while warm.
The absence of ferric sulphate may be ascertained by testing the
solution with potassium ferrocyanide ; no blue turbidity, or only
a very slight one, should occur.
Gelatin. — Solution obtained by digesting 1 part of isinglass
(ichthyocolla) with 50 parts of water, on a water- bath, for half an
hour, and subsequently filtering through cotton, moistened with
water.
Gold. — Metallic gold in the form of leaf.
Hifdrogen, Nascent, is a very delicate means of detecting arsenic.
The test depends upon the production of hydrogen arsenide (ar-
seniuretted hydrogen), whenever arsenic is present in any soluble
form, in which hydrogen is being evolved by the action of dilute
sulphuric or hydrochloric acid upon zinc or magnesium. From
the hydrogen arsenide the arsenic can be separated in a charac-
teristic and unmistakable form, either as metal, or by leading the
gas into a solution of an easily reducible metallic salt, as, for
instance, argentic nitrate, in which case the silver is precipitated
and a solution of arsenious acid is obtained.
AsH, + SBfi 4- 6AgN03= HjAsO, + 6HN0, -f 3Ag,.
Marsh's I'est, — Of the difterent methods for the application
of this test, the one long and commonly known as Marsh s test is
pre-eminently adapted for the recognition, as also for the quanti-
tative estimation of small amounts of arsenic.
A complete and simple form of apparatus for the application of
Marsh's test is represented in Fig. 20. It consists of a gas generating
flask or Woulff's bottle (A), of about 800 to 400 cubic centimeters
(10 to 14 ounces) capacity, provided by means of a peforated cork
or rubber stopper with a funnel tube (^), and a drying tube («),
loosely stopped at each end with a small plug of cotton, and par-
tially filled with dry calcium chloride in small fragments, followed
by a layer of small pieces of dry potassium hydrate; the latter
serving to retain any acid which may accidentally be carried
over with the gas, as also any trace of hydrogen sulphide. The
end of this tube is connected with a reduction tube (tZ), of hard
German glass, narrowly drawn out in one or more places, and at
the end into a capillary point, and bent up so as to form a vertical
jet, as shown in Fig. '20.
The test consists in introducing into the flask (A) pure granu-
lated zinc or magnesium, and adding gradually, by means of the
funnel tube, a cold mixture of one part of sulphuric acid and
3
REAGBNT8 AND TB8T SOLUTIONS. 3£
After the evolution of gas has continued long enough to expel
the atmospheric air/ the reduction tube {(f) is heated to redness
in the part indicated in the figure for about ten minutes, the
escaping gas is lighted, and a piece of white porcelain is held in
the flame. If no dark dejx>sit takes place, either in the tube or
on the porcelain, the reagents may be considered pure, and the
liquid to be tested may then be added through the funnel tube (6),
first in small amounts, and the operation continued in the manner
described.
If arsenic-spots or mirrors are obtained in the tube, a number
of them may be produced by heating the tube in at least two
places, at distances of about three inches, or if an approximately
quantitative estimation of the arsenic is desired, all the arsenic
may be obtained by the employment of a hirger reduction tube
and several flames (Fig. 21). The obtained arsenic mirrors may
be examined for identification, or quantitatively determined by
subsequently removing the tube and deierinining the increase in
weight.
In cases where it is desirable to estimate the entire amount of
arsenic, and guard a*:^ainst possible loss, instead of allowing the
developed gas to burn, it is preferable to conduct it into a solu-
tion of argentic nitrate, in which case any arsenic which may
have escaped reduction in the ghiss tube will be recovered, and
contained in the solution as arsenious acid, together with the ex-
cess of the undecom posed silver salt.
As is well known, certain compounds of antimony, when brought
into Marsh's apparatus, give rise to the formation of hydrogen
antimonide (antimoniuretted hydrogen), analogous in composition
to hydrogen arsenide, which, when subjected to the same process
of reduction as above described, produces black spots of metallic
antimonv. These spots are so different in their physical appear-
ance and properties as to be readily distinguished by the experi-
enced operator, and, when subjected to chemical tests, display so
marked a difference that iheir discrimination from those of arsenic
is readilv efl'ected.
To enumerate in detail all the special tests for each of these
two metals would lead beyond the scope of this work ; the prin-
cipal distinctive characters, however, will be briefly described.
The mirror of arsenic, as obtained in the reduction- tube, when
gently heated during the simultaneous development of a current
of hydrogen, can easily be driven from one place to another,
and, if the gas be allowed to escape at the exit tube, the develop-
ment of the arsenical or garlic-like odor can at the same time
be observed ; whilst antimony, on account of the much higher
temperature required for its volatilization, cannot be so readily
' This maybe determined by holding an inverted dry test-tube over the j>oint
of exit of the gas for a few seconds, and then bringing tlie mouth of the test-
tube in contact with the flame ; if the air be entirely expelled from the appa-
ratus, the gas bums quietly, if not, a slight explosion ensues.
86 MANUAL OF CHEMICAL ANALYSTS.
removed from the place in which it was deposited, and the
ei^caping gas is quite odorless.
The spots of arsenic, obtained by holding the cold surface of a
piece of white porcelain in the flame during the development of
the hydrogen arsenide, have a bright metallic lustre, whilst the
spots of antimony have a dull velvety black appearance. When
touched with a solution of sodium hypochlorite or chlorinated
lime, the arsenic spots become immediately dissolved, whereas
the spots of antimony remain unaffected ; by this means arsenic
can be detected, even when accompanied by antimony.
The spots of arsenic, when touched with a drop of a solution of
ammonium sulphide, and gently warmed, become completely dis-
solved, and, on being allowed to dry, display the bright yellow
color of arsenious sulphide: antimony under the same circum-
stances gives an orange-red coloration of antimonious sulphide.
The yellow arsenious sulphide remains unaffected upon the addi-
tion of a drop of hydrochloric acid, whilst antimonious sulphide is
readily dissolved ; and inversely a solution of ammonium carbonate
dissolves the arsenious sulphide, but does not act upon the anti-
monious sulphide. These few points of distinction in relation to
this important and characteristic test are suflficient in the majority
of cases to render possible a prompt determination, as to the pre-
sence or absence of one or both of these metals, and to effect
their discrimination.
Precautions to he observed in the Apjdi cation of Marsli's Test for
Arsenic, — Although this test is so delicate Jis to render possible
the detection of exceedingly small amounts of arsenic, certain
])recautions are necessary, which, if not observed, may prove a
source of serious error, and lead to incorrect inferences.
The sulphuric acid employed for generating the hydrogen gas
should be free from the lower oxy-acids of sulphur and selenium,
of the proper dilution, and cold; for if concentrated and warm,
sulphurous-acid gas will be produced, which, combining with the
nascent hydrogen, forms hydrogen sulphide, and a precipitation
of arsenic as insoluble sulphide would result.
Nitric acid and nitrates, free chlorine and other similar oxidiz-
ing agents must be rigidly excluded in the application of the
test, as preventing the formation of the gaseous hydrogen arsenide.
Ilydrochloric acid can also not be substituted to advantage for
the sulphuric acid for the generation of the hydrogen, for although
it docs not interfere with the formation of hydrogen arsenide, yet
on account of its greater volatility, and tendency to the produc
tion of the so called ziyic spots, the presence of arsenic might be
erroneouslv infrrred.
Another test which may be employed for the detection of
small amounts of arsenic, and which commends itself for con-
venience of application, is that known as:
Fleitmann'^s Test, — This consists in the generation of hydro-
gen by the actioh of a strong solution of potassium or sodium
KBAQIISTS AND TEST SOLUTIONS.
37
hydrate on metallic zinc or aluminium, hy tlie aid of Fio- 23.
heat. The operation may be performed quickly in a
loDg test-tabe, taking care that the tul>e ia only filled
to about one-tenth of its capacity. As soon as the gas
is generated, the solution to be tested is cautiously
sdded to the alkaline liquid, and a cap of white filter-
ing tiapcr, moistened with a drop of solution of ar-
gentic nitrate, placed over the tube (Fig. 22), If
arsenic is present, a purplii^h-black spot, due to the
reduction of the argentic nitrate to metallic silver,
win be produced UjJon the moist paper cover. Tliis
reaction is of particular importance and value, for
while antimony combines with hydrogen evolved from
dilute acids and zinc, it does not combine with hydro-
gen evolved by tlie action of an alkali on the same
metal.
Hydrogeo SulpMde (Ilydrosulphuric Acid, or Snl-
fihuretted Ilydrugcn). — Obtained by the action of di-
uted sulphuric or liydrochloric acids upon ferrous sul-
phide. Among the several convenient forms of ap-
paratus for the continuous preparation of the gas and
to keep it ready for use, the one represented in Fig. 23
is frequently employed. It consists of three glass
bulbs, the two lower ones being a single piece, and the
upper one, prolonged by a tube reaching to the bottom
of the lower, being ground air-tight into the neck of the second.
Through the tubulure of the middle bulb the ferrous sulphide is
introduced, and the tubulure then
closed by a cork containing a wide Fio. 23.
glass tube provided with a stop-
cock, or with a rubber tuVje, closed
bv a Mohr's wire clamp (see p. 74).
The acid is poured in through the
safety-tube, runs into the bottom
globe, and rises to overflow the
ftrrous sulphide in the middle one.
Witen the air lias been allowed to
escape through the delivery-tube,
and this is closed, the pressure of
the accumulating hydrosen sul-
phide forces the liquid from llie
second bulb down into the lower,
and thence into the upper bulb,
ihua stopping the action, and pre-
serving a volume of the gas ready
for use.
Another form of apparatus,
which is recommended for sim-
88 ' MAM'AL OP ClISMICAL A^tALVSIS.
plitrity of conBtructioo and the fncilily with wliiirh it may 1 -
cleaiified or BUppHe*! with fresh material, is represented in Fig. 24.
A glass gvlinder, about 40 centimeters (nearly IS inche,') high,
ann t'2 centimeters (■!( inches) wide, \a partially filled with diluted
salphnric acid. It is closed with a cork or rnbber stopper having
ft lateral noieh, and carrying a rather long tube, drawn out at its
lower end lo a small point. This tube is filled with coarse frag-
ments of ferrous Hnlpbide, and is closed with a tightly fitting cork
or rubber stopper, through which the delivery-tube (provided
with a mop-cock) passes.
When tlie apparatns is not in nse, the tnn%r cylinder is drawn
upwards. iinlU its point merely is immersed in the liquid. When
the gas ia required, the tube is depressed to the
Fio. 24, position shown in the figure, and the stop awk
opened. The acid then enters from below, and
generates a more or less rapid current of the
gas, which may be regulated by mesins of the
stop-cock. When the latter is closed, the pres-
sure of gae inside the inner tube forces the
liquid back into the glass cylinder.
When the above described forms of appa-
ratus are not at hand, hydrogen sulphide may
be generated, in small tests, from a little llask
or test-tube (Fig. 25), taking care that none of
the contents of the flask pass through the de-
livery-tube into the liquid under examination.
Hydrogen Sulphide Water.^A solutionof hydrogen sulphide (hy-
dniHiilphiirii: acid, or fiulpliurctted hydrogen) in water, saturated
at li>"' C. (5U° P.), or at a lower tem(>erature, containing about
four times its volume of the gas. The gas ia obtained, as above
dupcribed, by the action of diluted sulphuric acid upon ferrous
sulphide, anil is wiuth<.«l by water, contained in a small flask or
cvlindcr (Fig. 28), before pa.-»Bing it into water fur absorption.
In order lo pryserve the hydrogen sulphide in this form, it is
advisable to till the froshly-prepared saturated solution immodi-
Blely into small vials, and to place them, tightly corked, iu an
inverted jMtsition, in a cool place.
When, in the course of a test, a solution has to be acted upon
AND TEST SOLUTIONS.
39
for some time by hydrogen sulphide, a test-tube or flask may be
employed, of Biich sizo as nearly to be tilled by the liquid. It
may then be tightly stoppered, allowing sulSeienI escape of air
before corking, if it has to be warmed.
Indigo Solution (Solution of Indigo in Sulphuric Acid).— 1 part
of linely powdered indigo is gradually added to 6 parts of fuming
suljihuric aiiid; the mixture, after having been well stirred, is
tlion allowed to repose in a covered vessel for about two days,
when it is poured into 20 times its volume of water, the solution well
mixed, filtered, and preserved for use in a glass- stoppered bottle.
Iodine Water. — A saturated solution of iodine in water.
lodinized Potaasiam Iodide. — Solution of 1 part of iodine and 3
jiaris of poiii'^'iiiKi iodide in 60 parts of water.
SlftgnGSiiiD]. — Mfiiillic magTicsium in the form of wire or ribbon.
MagneBium Dlisturo (Ammoniated Magnesium Sulphate). — A
solution of 11 parts of cryslaliized magnesium chloride or sul-
pliatc and 14 jinrts of ammonium chloride in 70 parts of stronger
arnmoniu water and 130 parts of water. (Magneiiium chloride is
to lie preferred to the sulphate in the preparation of the solution,
ns having less tendency in its application ta pntduce basic salts.)
MaBnesioin Snlphate. — Solution of 1 part of crystallized mag-
nesium .'*ul]ilu\ti.' ill 10 parte of water.
Bteronrio Chloride. — Solution of 1 part of crystallized mercuric
chloride in 2il parM .>f water.
IBeroorio OxycMoride {BohUn's Reagent).— To a dilute solniiou
of mercuric chloride in water {1 : 80) a dihite solution of potas-
sium carbonate (1 ; 50) is added, drop by drop, with constant
agitation, until a perfectly neutral solution is obtained.
Phosphorous Salt (.SoJium-ammonium-hydrogen Phosphate).
40 MANUAL OP CHEMICAL ANALYSIS.
Platinic CUorlde. — Solution of 1 part of platinic chloride in 20
parts of water.
Plumbic Acetate. — Solution of 1 part of crystallized plumbic
acetate in 10 parts of water.
Plumbic Nitrate. — Solution of 1 part of crystallized plumbic
nitrate in 10 parts of water.
Potassium Acetate. — Solution of 1 part of potassium acetate in
5 parts of water.
Potassium Antimoniate. — A cold, saturated, a(][ueous solution of
potassium antimoniate.
Potassium Bicarbonate. — Solution of 1 part of potassium bicar-
bonate in 10 parts of water.
Potassium bichromate. — Solution of 1 part of potassium bichro-
mate in 10 parts of water.
Potassium Carbonate. — Solution of 1 part of pure potassium
carbonate in 3 parts of water.
Potassium Cluromate, Neutral. — Solution of 1 part of potassium
chromate in 10 parts of water.
Potassium Cyanide.
Potassium Ferrlcyanide. — S(jlution of 1 part of potassium ferri-
cyanide in 10 parts of water. To be prepared as required.
Potassium Ferrocyanide. — Solution of 1 part of potassium ferro-
cyanide in 10 parts of water.
Potassium Hydrate (Liquor Potassa?, U. S. P.).— Containing 5
per cent, of potassium hydrate.
Potassium Iodide. — Solution of 1 part of potassium iodide in 20
parts of water.
Commercial potassium iodide <K*casionally contains traces of
potassium iodate, and this should V)e eliminated by dissolving the
salt in boiling alcohol, to saturation, filtering the hot solution, and,
when cool, collecting and drying the separates! salt.
Potassium Mercuric Iodide!^— A solution of IMo grams of mer-
curic chloride and 4.98 grams of potassium iodide in 100 cubic
centimeters of water.
Potassium Mercuric Iodide with Potassium Hydrate {yesslers
Test). — 10 grams of potassium iodide arc dissolved in 10 grams of
hot water, and a hot solution of 5 grains of mercuric chloride
lidded until the ])recipitate of mercuric iodide ceases to be dis-
solved. The mixture is then tillered, the filtrate mixed with a
concentrated soluti<m of 80 grams of potassium hydrate, and
ililutfd to the measure of )iO() dubic centimeters. To this solu-
tion '} cubic centimeters of the above-prepared mercuric chloride
solution are subsequently adde<l, and tlu' liquid, atter having been
allowed to become perfectly clear by standing, preserved in well
stoppered bottles.
Potassium Nitrate.
Potassium Nitrite.
Potassium Permanganate. — Solution of 1 i)art of potassium per-
manganate in 1000 parts of water.
RBAOBNTS AND TEST SOLUTIONS. 41
Potassium Sulphate. — Solution of 1 part of potassium sulphate
in 15 parts of water.
Potassiom Sulphocyanide. — Solution of 1 part of potassium sul-
phocyanide in 20 parts of water.
Soda-lame. — Quicklime is slaked with a solution of sodium
hydrate, of such a strength that about 2 parts of quicklime are
mixed with 1 of sodium hydrate; the product, after drying, is
heated to bright redness, subsequently finely powdered, and pre-
served in tightly stoppered bottles.
Sodium Acetate. — Solution of 1 part of crystallized sodium
acetate in 5 parts of water.
Sodium Bicarbonate. — Saturated aqueous solution of sodium
bicarbonate.
Sodium Bitartrate. — Saturated aqueous solution of sodium
bitartrate.
Sodium Carbouate. — Dehydrated by exsiccation.
Sodium Carbouate. — Solution of 1 part of crystallized sodium
carbonate in 10 parts of water.
Sodium Hydrate (Liquor Sodoe, U. S. P.).— Containing 5 per
cent, of sodium hydrate.
Sodium Hyposulphite. — Solution of 1 part of crystallized sodium
hyposulphite in 10 parts of water.
Sodium Molybdate.
Sodium Phosphate. — Solution of 1 part of crystallized sodium
phosphate in 10 pans of water.
Stannous Chloride. — Saturated solution of real and pure tinfoil
in concentrated hydrochloric acid, with subsequent addition of a
little concentrated hydrochloric acid.
Starch Mucilage (Gelatinized Starch). — 1 part of finely powdered
starch is triturated with a little water, the mixture diluted with
about 100 partij of water, and subsequently heated to the boiling-
f)oint; after cooling, and having been allowed to subside, the clear
iquid is decanted. The reagent should be freshly prepared, when
required.
Zinc. — Metallic zinc in slender sticks, or small fragments, or in
thin disks, prepared by melting and pouring in a thin stream into
water.
PREPARATION OF TEST PAPERS, ETC.
Neutral Litmus Solution is prepared by digesting 1 part of com-
mercial litmus with alcohol, with the aid of a gentle heat, for
about fifteen minutes ; the alcoholic liquid, which contains objec-
tionable coloring matters, is decanted, and the litmus subsequently
extracted with about 10 parts of water, by digestion on the water-
bath, and filtered.
Tiie filtrate thus obtained is divided into two equal parts; to
one of them, by means of a glass rod, very dilute sulphuric acid
is added, with constant stirring, until the liquid turus faintly red ;
42 MANUAL OF CHEMICAL ANALYSIS.
the red liquid is then added to the reserved blue portion, and the
whole well mixed.
If it is desirable to preserve the solution for any length of time,
about 5 per cent, of alcohol should be added, or it must be kept
in bottles provided with a perforated stopper, through which a
bent glass tube may be inserted, or loosely stopped with cotton, in
order to admit access of air, and exclude dust; if these precau-
tions be neglected, the solution soon becomes mouldy or dis-
colored, and unfit for use.
Blue Litmus-Paper is prepared by drawing unsized white paper
(Swedish filtering-paper) through the above neutral liquid.
Red Litmus-Paper is prepared by drawing unsized white paper
(Swedish filiering-paper) through the acidulated reddened part of
the litmus solution, as obtained and described above, in the prepa-
ration of neutral litmus solution.
The paper thus prepared is dried in warm air by suspension
over a thread, and for ready use is cut into strips about one-third
of an inch wide and four inches long, and preserved inclosed in
paraffin-paper, or in tightly corked bottles, protected from the light.
In reactions of neutralization, where carbonic aid gas is
evolved, this substance acts on litmus, and may impair the cor-
rectness of the test ; in such operations it is therefore better, if
admissible, to o})erate on warm solutions, in order quickly to
expel the carbonic acid gas; if heat be incompatible, turmeric-
paper may be used instead of litmus-paper.
Turmeric Solution. — Obtained by digestion of 1 part of powdered
turmeric in a mixture of 4 parts of alcohol and 3 parts of water.
After one or two days, the liquid is filtered oft* and preserved.
Turmeric-Paper is prepared from this tincture by steeping in it
white unsized paper (Swedish filtering-paper). The y)aper need
not be preserved from the action of the atmosphere, since it
remains unchanged by carbonic acid.
Alkanet-Paper is prepared like litmus-paper, by saturating un-
sized paper with a solution of the alkanet-red. This is obtained
by extracting dry alkanet root with ether; the filtered solution is
ready fi^r use.
The blue paper may be obtained from the red one by dipping
it into an acjueous solution of sodium carbonate (1:500). A neu-
tral paper, answering for the alkaline as well as the acid test, may
be prepared by dividing the ethereal solution of alkanet-red into
two equal parts; to one is added, drop by drop, an aqueous solu-
tion of sodium carbonate, until the red is just changed to a dis-
tinct blue tint; then both liquids are mixed and used for the
preparation of the paper.
Plumbic Aoetate-Paper serves for the detection of hydrogen sul-
phide, and is prepared by dip[)ing white unsized paper (Swedish
filtering- paper) into a solution of plumbic acetate, and, when dry,
cutting into strips of a convenient size, which may be preserved
inclosed in paraffin-paper.
A SYSTEMATIC COURSE
OP
QUALITATIVE CHEMICAL ANALYSIS.
Chemical tests and examinations must be founded upon a
thorough knowledge of the nature and relations of the reagents,
and of their deportment with the common compounds, and also
upon a certain fixed order and meth(xlical system in their a])pli-
cation. These attainments, and the necessary skill, experience,
and judgment, are requisite for every one who enters upon testing
and investigation with a chance or claim of accuracy or certainty.
It is advisable in analytical work to enter the result of each
test as soon as satisfactorily completed into a notebook, whereby
the brief symbolic notation may be used to advantage; the
analysis is thus recorded, step by step, as it progresses until com-
pleted.
It may also be stated here that a reasonable economy with the
substance under examination, especially if only of a small quan-
tity, and with its solutions is necessary, so as to leave enough of
the former for unseen contingencies and for confirmatory tests,
as well as to repeat or verify any and all results of the examina-
tion. All tests and reactions are, therefore, performed on as small
a scale as is reasonable and appropriate in the particular case ;
and all operations should proceed accordingly, and with constant
observance of the principles and processes whereon they depend.
Ti)e following brief outline of a simple progressive course ot
qualitative chemical analysis depends, first, upon the successive
elimination of groups of elementary compounds which possess
certain common chemical properties, and, finally, upon the recog-
nition of each member of such groups ; it may therefore serve as
a guide whenever, in the course of investigation, recourse is to be
had to such a systematic method of analysis.
When the object of the examination is only to establish the
presence or absence of some particular substance, the character-
istic reagent may be employed at once, provided there be no other
substance present which would interfere with, or exclude, the
direct application of the test; but, if a qualitative analysis is
required, the substance, if a solid body, may be subjected first to
44
HANCAL OF CI1EM[CAL ANALYSIS.
a preaminary examin<itioQ in the drv way, by which means
a[»proximate information as to its composition may be obtained;
after this, it is dissolved and examined. The course of qualitative
analysis, therefore, consists of three parts :—
I. Preliminarv examination in the drv wav.
II. Solution, or conversion into the liquid form.
III. Analysis of the solution.
This consists in an accurate observation, often by the aid of a
lens or a microscope, of the physical properties of the substance,
its form, color, hardness, gravity, and odor, and of its deportment
at a high temperature, either alone, or in contact with some
chemical compound which prinluces decomposition.
Fig. 27.
1. The substaxce is he.vted lv a dry narrow tube opest
AT BOTH ENDS (Fig. 27).
(") The suUtance remains unaltered: indicating absence of
organic matter, of salts containing water
of crystallization, and of volatile com-
pounds.
{h) Xon- volatile organic substances car-
bnihe and blacken, evolving emp3'reu-
matic, inflammable gases.
(o) The siif >s (a nee fuses, expelling aqueous
vapors, which condense in the cooler parts
of the tube: indicatinfr salts with water
of crystallization (these will generally re-
solidify after the expulsion of the water),
or decomposable hyrlrates, which often
give oft* their water without fusing. The
acid or alkaline reaction of the condensed
va]>ors should be determined by means
of litmus-paper.
('/) A chanije of color takes place : zinc
o.\ide assumes a yellow color while hot,
which disappears again on cooling: mer-
curic oxide shows a transitory brown coloration, followed by the
sublimation of metallic mercury : mercuric iodide sublimes with
a yellow colr»r ; chromates, and the oxides of lead and bismuth
are colored brown.
(/r) G'fs^s or funv's are evolv*'d : iodine or bromine vapors would .
indicate their respective compounds, and may be recognized by
the violet or brownish-red color and characteristic oTor of the
vapor; sulphur dioxide is often produced by the decomposition
of sulphates; nitric peroxide arises from the decomposition of
many nitrates, and is recognized by its brownish color and suftb-
QUALITATIVE CHEMICAL ANALYSIS. 45
eating odor ; cyanogen is recognized by its odor, and would indi-
cate such cyanogen compounds as are decomposable by beat
(mercuric cyanide) ; ammonia vapors may arise either from the
decomposition of ammonium salts, cyanogen compounds, or from
nitrogenous organic compounds; in the latter case carbonization
takes place, and either cyanogen or empyreumatic fumes escape
with the ammonia.
(/) Sublimates are formed by volatile substances, such as sul-
phur, ammonium salts, compounds of mercury, arsenic, and anti-
mony, and some organic acids (benzoic, succinic, oxalic, salicylic,
etc.). Sulphur sublimes in reddish-brown drops, which, upon
cooling, assume a yellow or yellowish -brown color; metallic
mercury forms globules, which are sometimes only distinguish-
able by the aid of a lens: mercuric chloride melts before volatil-
izing, and mercurous chloride sublimes without previously melt-
ing ; when touched with a solution of potassium hydrate the
sublimate assumes a yellow color with mercuric, a black one with
mercurous salt ; metallic arsenic forms the well-known mirror,
arsenious acid small octahedral crystals, and the sulphides of
arsenic a reddish-yellow, or, when cold, yellow sublimate ; anti-
monious oxide melts first to a yellow liquid, and then sublimes in
bright, shining needles.
2. The substance is mixed with soda-lime, and heated in
A DRY GLASS TUBE (Fig. 28).
The development of ammonia vapors will indicate ammonium
salts, or nitrogenous compounds.
Fig. 38.
46
' CHBMICAL ANALYSIS.
8. The substance is mixed with drieti sodium carbosate,
and heated on charcoal in the reducing flame of
THE BLOWPIPE (Fig. 2y).
(a) Fusion and alsorption into the coal indtcato alkalies, or
their sails.
{h) An infusilh white residue, either at once or after previous
fusion in the wuler of crystMlliziition, iiidicales eoinpounds of
calcium, barium, fltroDlium,
Fio- 98- magnesium, aluminium,
zinc, or tin.
(c) A reduction to the me-
tallic ttatr takes place, with-
out formation of a periph-
eric incrtiaittCion upon the
charcoal, Compoundsof tin,
silver, and copper, give
malleable shining scales.
Compounds of iron, nian-
ganese, cobalt, and nickel,
aie reduoed to a gray in-
fusible powder; nil visible
upon cutting the fuse from the oonl, and triturating and levigating
it in an agate mortar (Fig. 30).
FiQ, 30.
i
(d) Reduction with incrustation: Antimony com|)ound8 give a
brittle metallic globule and a white incrustation ; bismuth, a
brittle globule and a brown-yellow incrustation; lead, a mallea-
ble globule and a yellow incrustation : nine and cadmium are not
reduced, but give, the former, a while incrustation, not volatile
in the oxidizing dame, the latter, a brown-red incrustation,
(«) Arsenic compounds evolve the smell of garlic.
(/) Borax and alum intumesce, and lose their water of crystal-
lization.
(rj) All sulphur compounds give an alkaline sulphide, which,
when moistened upon a clean silver phile, produces a black stain,
aud with acids develops hydrogen sulphide.
QUALITATIVE CHEMICAL ANALYSIS. • 47
(h) If deflagration takes place, nitrates, chlorates, iodates, or
bromates are indicated.
4. The substance, contained on the looped end of a
mounted platinum wire (fig. 31), is heated in the
upper reducing portion of the non-luminous gas
FLAME.
(r?) A violet color imparted to the flame indicates potassium
salts. As this reaction may be perfectly concealed by the pre-
sence of sodium salts, the flame should be observed through blue
glass.^
Fig. 81.
(h) A yellow color imparted to the flame indicates sodium salts.
(c) The substance is moistened with hydrochloric acid, and the
color of the flame observed ; a purplish-red color indicates. stron-
tium, a carmine-red, lithium, and a yellowish-red color, calcium
salts ; a green coloration indicates either copper or barium salts,
more evident with the former than with the latter.
(d) The substance is first heated to deprive it of moisture, then
moistened with a drop of strong sulphuric acid, and the color of
the flame observed ; a green coloration may indicate phosphoric
or boric acid, which, however, particularly when sodium com-
pounds are present, is only of transient duration.
(e) A blue coloration imparted to the flame may indicate ar-
senic, antimony, or lead compounds.
5. A SMALL AMOUNT OF POWDERED BORAX IS MELTED ON THE
LOOPED END OF A PLATINUM WIRE, BROUGHT IN CONTACT
WITH A TRACE OF THE SUBSTANCE TO BE TESTED, AND
HEATED :
(a) In the outer blowpipe flame, or in the lower oxidizing por-
tion of the non-luminous gas flame.
A blue glass or bead indicates cobalt.
An amethyst red colored glass indicates manganese.
A green glass indicates chromium or co))per (the copper bead
becomes blue on cooling, the chromium bead yellowish-green).
A brown -red glass indicates nickel or iron (the iron bead,
when cold, is often of a yellowish color).
A yellow glass indicates uranium or lead.
' Tbe bine glass, which is tinted with cobalt monoxide, possesses the pro-
perty of absorbing tlie yellow rays of light, and permits only the blue and
violet rays of the spectrum to pass througli it.
48 * MANUAL OF CHEMICAL ANALYSTS.
A colorless glass indicates molybdic acid, tin, antimony, and
bismuth, as also the alkaline earths; the latter, however, be-
coming opaque on cooling.
(h) In the inner blowpipe flame, or in the lower reducing por-
tion of the non-luminous gas-flame.
A blue glass indicates cobalt.
A yellow or brownish-red glass indicates copper or molybde-
num.
A green glass indicates chromium, iron, or uranium.
A gray glass indicates nickel, bismuth, silver, or antimony.
A colorless glass indicates manganese, as also the alkaline
earths; the latter showing the same behavior in both the re-
ducing and the oxidizing flames.
The operation of reduction is usually more easily accomplished
by the use of phosphorous salt, instead of borax ; the former pro-
ducing in the oxidizing flame with the oxides of manganese,
cobalt, chromium, copper, iron, nickel, antimony, and molybde-
num, and in the reducing flame with the oxides of cobalt, iron,
uranium, chromium, copper, bismuth, and silver, the same results
as with borax; the oxides of bismuth and silver, however, yield
a yellow colored glass. With either phosphorous salt or borax,
and heated in the oxidizing or reducing portion of the flame,
silica and silicates produce a skeleton in the bead.
II. SOLUTION OF SOLID BODIES.
After having ascertained, by the }>reliminary examination, to
what class of bodies the substance under consideration belongs, it
has then to be brought into the liquid form — in other words, to
be dissolved. The usual solvents which are employed are water,
hydrochloric, nitric, and nitro-hydrochloric acids. The finely pow-
dered substance is first boiled with from 12 to 20 times its weight
of distilled water, in order to ascertain its complete or partial
solubility, or its insolubility therein. If it be not completely dis-
solved, the ])ortion insoluble in water is collected upon a filter, and
is then treated successively with dilute and concentrated hydro-
chloric acid; by this process carbonates evolve carbonic-acid gas,
with effervescence; })eroxides, chromates, and chlorates, evolve
chlorine ; cyanides give hydrocyanic acid ; many sulphides, hy-
dro^^on sulphide; sulphites and hyposulphites, sulphurous acid.
If hydrochloric acid does not completely dissolve the substance,
it generally eflects the separation of one or more of its constitu-
ents; for this reas(m the solution should be separated from the
residue and examined apart. The residue may consist of com-
pounds undecomposable by hydrochloric acid, which existed in
the original substance; or of insoluble compounds formed by tlie
decomposition of the original substance by hydrochloric acid.
Thus sulf)hur is separated from polysulphides, and pulverulent or
gelatinous silica from silicates; or, if lead, silver, or mercurous
QCALITATIVB CnSMICAL ANALYSTS. 49
«
salts be present, insoluble chlorides of these metals will be formed.
In this latter case, argentic chloride may be distinguished by its
solubility in ammonia water, and mercurous chloride by its con-
version by ammonia into the gray colored dimercurous ammo-
nium chloride, or its reduction by potassium or sodium hydrate
to black mercurous oxide ; while plumbic chloride is characterized
by its solubility in hot water, from which it separates in a crys-
talline form on cooling.
If the substance is not completely soluble in hydrochloric acid,
the insoluble residue is treated successively with nitric and nitro-
hydrochloric acids, which either act as mere solvents or exert an
oxidizing action.
When a finely powdered substance is not dissolved by succes-
sive treatment with either of these solvents, it must be rendered
soluble by other means, in order that its constituents may be de-
termined. This is generally accomplished by fusion with 3 to 4
parts by weight of alkaline carbonates, in the case of the sulphates
of barium, strontium, calcium, and lead, and also of silica and sili-
cates, or by fusion with acid potassium sulphate in the case of
alumina or alumiuates.
In the process of fusion with alkaline carbonates, as above
described, in cases where arsenic or an easilv reducible metal
(antimony, tin, lead, bismuth, etc.) is present, the application of
platinum crucibles should be avoided (see note on page 23).
III. QUALITATIVE ANALYSIS OF SOLUTIONS.
I. Examination for Bases.
In the systematic course of examination for metals, now gen-
erally employed, use is made of the analogy in physical and
chemical properties, and especially in the solubilities of certain
classes of compounds; the reagents which give rise to the forma-
tion of these compounds are; hydrochloric acid, hydrogen sul-
phide, ammonium sulphide, ammonium carbonate, and ammonium
phosphate. Their application depends upon the different solubility
and insolubility of metallic chlorides and sulphides, and of the
carbonates or phosphates of the alkaline-earthy and alkali metals.
By means of these general reagents, the metallic compounds are
divided into several groups, and are successively eliminated from
their solutions, whereby the detection of each individual member
of such groups is considerably facilitated.
Group I.
Metals whose chlorides are insoluble^ or nearly so, in tvater and
dilute acids :
Silver white )
Mercurous salts, white; [«"'npletely precipitated.
Lead, white, incompletely precipitated.
4
50 IIA9UAL or CnBMICAL ANALYSIS.
OrMtpIL
if^-taU uhose siilpliides are insoluble, or nearly so^ in water and
dibits acids: They are all precipitated from tbeir acid solutioDS
by riydrogen sulphide. They are divided into two subdivisions
according to their deportment with ammonium sulphide.
A. Metals whose sulphides are sulpho-acids, forming with sul-
pho-bases, soluble snlpho-salts:
Antimony, orange. Molybdenum, black-brown.
Arsenic, yellow. Gold, black-brown.
Stannous salts, brown. Platinum, black-brown.
Stannic salts, yellow.
B. Metals whose sulphides do not possess acid properties, not
combining with, and therefore insoluble in, alkaline sulphides:
Lead. black. Copper, black.
Mercuric salts,* black. Cadmium, yellow.
Bismuth, black-brown. Palladium, black,
Gnmpin.
ifttals whose sulphides form soluble sulpho-salfs, which conse-
quently are not precipitated by hydrogen sulphide from neutral
or acid, but partially from alkaline solutions ; which, however,
are completely precipitated by ammonium sulphide from neutral
as well as from alkaline solutions. These are, again, subdivided
into two groups:
A. Metals which are precipitated as sulphides:
Zinc. white. Nickel, black.
Iron. black. Uranium, black-brown.
Manganese, flesh-colored. Thallium, black.
Cobalt. black. Indium, yellow.
B. Metals which are precipitated as hydrates :
Aluininium.colorless and trans- Chromium, grayish-green.
parent. Cerium, white.
The oxalates, phosphates, and borates of barium, calcium, stron-
tium, and magnesium, being soluble in dilute acids and insoluble
in water, are similarly precipitated by ammonium sulphide.
GroapIV.
iftfals whose sulphides and hydrates are soluble in water; and
which, therefore, are not precipitated by hydrogen sulphide nor
by ammonium sulphide. These are subdivided according to their
deportment with ammonium carbonate in the presence of ammo-
nium chloride.
A. Metals whose normal carbonates are insoluble in water or
in solution of ammonium chloride:
Barium, Calcium, Strontium.
> M*Tcnric sniphirle is slightly soluble in i>otassiun[i sulphide, and cupric sul-
phide in ammoniam sulphide.
• • •
. • • ••
• • • •
a • . a •
QUALITATIVE CHEMICAL ANALYSIS. 51
B. Metals whose carbonates are soluble in water or in solution
of ammonium chloride:
Magnesium, Potassium, Sodium,
Lithium, Ammonium.
When entering upon the examination of a solution, the results
of the preliminary examination should be taken into due consid-
eration, as they often will indicate the number and kind of bases
present. If t&en a precipitate is caused by one of the general
reagents, the solution should be examined for every member of
that particular group. It is also evident that when the presence
of one or several bases has been ascertained, the systematic and
successive course of examination, as described hereafter, should
be pursued, so as to exclude beyond doubt the presence of any
not-detected metal.
The precipitation by each general reagent must be complete.
To insure this, they must be employed in the order above stated,
and must be added gradually, allowing the precipitate to subside
between each addition, until no further precipitate is produced.
In the case of hydrogen sulphide, the precipitation is complete
when the solution, after agitation, still smells strongly of the gas.
Gentle heat generally facilitates the separation of precipitates.
Each group, when precipitated, must be thoroughly freed, by
washing with water, from all members of the subsequent groups,
which may be contained in the solution. After the precipitation
of each group, it is advisable to ascertain the presence or absence
of any members of the succeeding groups, by evaporating on
platinum-foil a few drops of the filtrate; if, after ignition, there
is no distinctly visible residue, non-volatile substances need not
be looked for further. It is obvious that, if complete precipita-
tion and thorough washing be neglected, metals belonging to one
group are liable to be found among those of another group ; and,
consequently, as the analysis proceeds, reactions will be obtained
which will be a source of perplexity and errors.
Hereupon the following course of analysis may be pursued,
involving the systematic investigation of the several groups :
Group I.
A portion of the solution is acidulated with livdrochloric acid.
An ensuing precipitatej which may be marked No. 1, would indi-
cate lead, silver, or mercurous chlorides. In this case the pre-
cipitate is collected on a filter, washed and subsequently boiled
with water, and the solution filtered while hot.
Lead chloride is soluble in hot water, and can be precipitated
from its solution as yellow lead chromate on the addition of po-
tassium chromate. Silver and mercaroos chlorides are insoluble
in water; the former, however, is readily soluble in ammonia
52 MANUAL OF CHEMICAL ANALYSIS.
water, from which solution it is aorain precipitated on the addition
of an excess of nitric acid, whilst mercurous chloride in contact
with ammonia is colored black.
Group n.
The liquid, acidulated with hydrochloric acid, or, if a precip-
itate was produced by the latter, the filtrate therefrom, is satu-
rated with hydrogen sulphide. If no precipitate ensues, the
reagents indicated in the next following group may at once be
em[)loyed; if, however, a precipitate has been formed, indicating
bases of group II , this is collected on a filter, well washed with
water, and the filtrate and washings, which may be marked
Filtrate No. 2, reserved for further examination. The preoipi-
tate, which may be marked No. 2, is then examined as follows:
If it is of a light yellowish-white color, it may consist simply of
sulphur, which may be recognized by its volatility when heated
in a small glass tube, or by the formation of an alkaline sulphide
when heated with a little exsiccated sodium carbonate on char-
coal, before the blow-pipe. The precipitation of sulphur results
from the presence of ferric salts, chromic acid, or chromates; in
the first case, the ferric is reduced to ferrous salt, and in the latter,
the chromic acid to chromic oxide, which imparts a green color to
the solution. When considerable free nitric acid is present in a
solution, sulphur may also be precipitated by the decomposition
of hydrogen sulphide.
A ydhw precipitate is produced when arseniousor arsenic acid,
stannic acid, or cadmium salts are present in the solution. If
arfienic is present ill the form of arsenic acid, the solution must
Vje heated before or during the time of saturation with the gas,
and subsequently allowed to stand for a few hours in a closed
flask or test-tul>e, in order to insure its complete precipitation.
An oranye-colored precipitate is produced when antimony is
present.
A brown precipitate is produced by stannous salts, and the salts
of bismuth and molvbdenum.
A hhlr^c or blackish-brown precipitate is produced by mercuric
salts, lead, copper, gold, platinum, and palladium, as also by silver
and mercurous salts, in case the two latter were previously not
completely precipitated by hydrochloric acid.
It is evident that when several metals precipitable by hydrogen
8ul[)liide are present, the color of the precipitate will be unavail-
able as a criterion for the recognition of any one substance.
The metallic sulphides precipitated by hydrogen sulphide are
distinguished by their deportment with ammonium sulphide, being
soluble or insoluble therein, and may thus be resolved into two
clashes.
The preci])itate No. 2, collected upon a filter and well washed
QUALITATIVE CHEMICAL ANALYSIS. «53
with water, is digested with ammonium sulphide, by the aid of a
gentle heat, and filtered. The solution may be marked A, and
any insoluble residue upon the filter, B.
The obtained solution A contains those metals whose sulphides
are sulpho-acids, combining with alkaline sulphides or sulphy-
drates to form soluble sulpho-salts. These are: arsenic, antimony,
tin, molybdenum, gold, and platinum. In order to effect their
separation, several methods may be employed, only one of which,
however, need be here described.
The solution A is acidulated with dilute sulphuric acid, and the
resulting precipitate (if not consisting only of sulphur) very
slightly warmed with a concentrated solution of ammonium car-
bonate. Arsenic is thereby dissolved, and, upon supersaturating
the solution with hydrochloric acid, and warming, is reprecipi-
tated as arsenious sulphide, and may then be reduced to the
metallic state by heating in a small class tube with a mixture of
potassium cyanide and exsiccated sodium carbonate (Fig. 32), or
Fio. 82.
it may be dissolved by gently heating with hydrochloric acid and
a little potassium chlorate, when upon the subsequent addition of
test magnesium mixture, a white crystalline precipitate of ammo-
nio-magnesium arseniate will be obtained.
Traces of arsenic may be more readily detected, after the above
treatment, by examining the solution in Marsh's apparatus (Fig.
33), as described on pages 33 to 36.
The portion undissolved by ammonium carbonate is dissolved in
hydrochloric acid, with the addition of a small amount of potas-
sium chlorate, and gently heating, and the solution thus obtained
tested as follows : A few drops are brought upon platinum-foil,
54
ANOAL OF CHEMICAL .
together witli a fragment of melallic zinc, when, if antimony is
present, a deep black spot will be produced upon the foil, or ihe
solution when brought into Mai-sh's apparatus, will develop hy.
drogen antimoiiide, which may be recognized by the uietliod de-
scrilKtd on page 85. Another portion of rhe (solution is warmed
will) metallic zinc, when tin will lie precipitated afl a black me-
tallic powder, soluble in warm hydrochloric acid, and producing
ujwtn the subsequent addition of solution of mercuric chloride a
wliite or gray-colored precipitate. Molybdennm may be be^t
detected by the testa of tlio preliminary examination, as described
on page 48. Gold may bo recopnincd by the brown precipitate of
finely divided metal on the addition of ferrous sulphate lo the
original slightly acid sohitition. Platinnm is delected by the
addition of a little ammonium chloride to the original, slightly
scid'BolutioD, evaf^iorating nearlv to dryness, and treating with
strong alcohol ; a yellow, cr_\-slanine precipitate, consisting Af the
double chloride of plnlinitm and ammonium, and reducible by
heating to black melnllic platinum, will tbna be formed.
The portion of the hydrogen sulphide precipitate B, insoluble
in ammonium sulphide, contains those metals whose sulphides do
not pas:«s9 acid pro[x;rties, not combining with, and therefore
insoluble in, alkaline sulphides or sulphydrntcs. These are: lead,
bismuth, copper, cadmium, and mercuric salts, also merourous
salts and silver, in case nitric instead of hydnxihloric acid was
employed for acidulating the original Bolutiou, before preoipi-
QUALITATIVE CHEMICAL ANALYSIS. 55
tatiug with hydrogen sulphide. The precipitate B is washed,
subsequently treated upon the filter with concentrated nitric acid,
and the filtrate examined as follows :
(1) Portion soluble in nitric acid.
Lead, which can be present in but small amount if the original
solution was acidulated with hydrochloric acid, as described under
group I. page 51, may be detected by neutralizing the solution
with ammonia water, evaporating to a small volume, and acidu-
lating with sulphuric acid ; a white precipitate will thus be pro-
duced, which is soluble in basic ammonium tartrate, and may be
again precipitated from this solution on the addition of potassium
chromate. The latter precipitate, when mixed with exsiccated
sodium carbonate, and heated upon charcoal, yields a soft me-
tallic bead.
Silver can only be present when hydrochloric acid was not
employed for acidulating the original solution, as directed under
group I. page 51. It may be detected in the filtrate from the
just-mentioned lead sulphate precipitate by the addition of hydro-
chloric acid, when a white curdy precipitate, soluble in ammonia
water, will be produced.
Bismuth may be detected in the filtrate from the preceding
silver precipitate by the addition of ammonia water, when a
white precipitate, insoluble in an excess of the reagent, will be
formed. The solution of the precipitate in a small amount of
hydrochloric acid, becomes turbid on the addition of much water.
Copper is recognized when the filtrate from the preceding bis-
muth solution possesses a blue color, and, after acidulating with
hydrochloric acid, by -a reddish-brown precipitate on the addition
of solution of potassium ferrocyanide.
Cadmium may be recognized, when the solution of the preceding
test remains colorless upon the addition of ammonia water, by a
yellow precipitate upon saturation with hydrogen sulphide. If,
however, both copper and cadmium are present in the solution,
then the ammouiacal liquid from the above-mentioned bismuth
precipitate is supersaturated with hydrochloric^acid, the solution
concentrated by evaporation, and ammonium carbonate in excess
added, when cadmium will be separated as a white precipitate,
whilst copper, remaining dissolved, imparts a blue color to the
liquid. The separation may also be eftected by adding potas-
sium cyanide to the ammoniacal liquid from the bismuth pre-
cipitate until the solution appears colorless; upon subsequent
saturation with hydrogen sulphide cadmium will be precipitated
as yellow cadmium sulphide, while copper remains in solution.
Palladium may be detected in the original solution of the sub-
stance under examination by the formation of a black precipitate
on the addition of solution of potassium iodide.
(2) The portion of precipitate B insoluble in nitric acid may
consist of sulphur, which is recognized by its yellowish or gray-
56' MASUjtL OP CHEMICAL ANALYSIS.
isb-yellow eoliir,' as al*! by its ootnplote volatilization vhen
heated in a small glass tube, or the formation of an alkaline sul-
phide, when heated with exsiccated sodium carb')nate on charcoal,
uefore the blow-pipe. Lmd sulphate forma a iieavv, white pre-
cipitate, and results From the action of the nitric acid on the lead
sulphide. In this caae lead will usually be found and recognized
also in that portion of the precipitate B which ia soluble in nitric
acid, page 55,
Meroury, in the form of mercuric salt, is recognized as a black,
floeeulent precipitate, which, when mixed with sodium carbonate,
and heated in a glass tube, yields a sublimate of metallic mercury,
I^ead sulphate may be separated from mercuric sulphide by digest-
ing with a solution of basic ammonium tartrate, in which lead
sulphate is soluble, and may be subsequently recognized by a black
precipitate with hydrogen sulphide, or a yellow one with jMtaa-
sium cbromatc. The washed mercuric sulphide may be dissolved
in nitro-hydroohlorio acid, the excess of acid removed by evapora-
tion, and the solution tested, either with stannous chloride, which
will produce a white precipitate, or by immersing a piece of bright
copper foil in the liquid, when a coauog of metallic luereury will
be deposited,
Groiip m.
Filtrale jVo. 2, page 52, is supersaturated with ammonia water,
and ammonium sulphide added, in an amount suGBcieut to efl'eot
complete precipitation, if any reaction is pnxluced. IT no precipi-
tate is formed by the addition of these reagents, the solution may
be further examined as directed under group IV., page 69. If,
however, a precipitate is produced, it is collected on a lilter, well
washed with water, and the filtrate, which may be markod Bo. 3,
reserved for the examination of the bases of group IV. This pre-
oipitate, marked No. 3, may contain iron, nickel, cobalt, manga-
nese, zinc, uranium, chromium, and aluminium, as also calcium,
barium, and strontium oxalates and phosphates and raagnesinm
phosphate. A brown color of the filtrate from precipitate No, 3
would indicate the presence of nickel.
A black precipitate will indicate iron, cobalt, nickel, uranium,
or one or all of these combined with other members of the group.
A (/reenisA precipitate will indicate chromium.
Afitsh-cohmd precipitate will indicate manganese.
A white precipitate is dependent in its character as to whether
the original substance was soluble in water, or whetlier in order
to effect its solution the aid of an acid was required. In the
former case, it may consist of zinc or aluminium, either alone, or
combined with manganese and chromium; in the latter case it
c aulpliide, wliicli lin-
QUALITATIVE CHEMICAL ANALYSIS. 57
may also contain magnesium, barium, calcium, or strontium, in
combination with phosphoric or oxalic acids.
Precipitate No, 3 (page 56) is examined as follows:
(a) It is first digested with cold, dilute hydrochloric acid. This
dissolves all the oxides and sulphides of the group, with the
exception of the sulphides of cobalt and nickel, which, if present,
are separately examined as directed under (c). The acid solution
or filtrate thus obtained is first heated, in order to remove the
hydrogen sulphide, filtered, and solution of sodium hydrate, in con-
siderable excess, added. If a precipitate is formed, it is examined
as directed under (b), whilst the alkaline solution or filtrate is
examined as follows: It is first boiled for some time, when ohro-
minm will be precipitated ; its identity may be confirmed by fusing
it, on platinum-foil, with an equal weight of exsiccated sodium
carbonate and potassium nitrate, dissolving the fused mass in
water, and, after acidulating with acetic acid, testing with plumbic
acetate, when a yellow precipitate will be produced. A portion
of tiie filtrate from the first chromium precipitate is then satu-
rated with hydrogen sulphide, when an ensuing white precipitate
will indicate zino; this may be confirmed by moistening i>art of
the precipitate, on the looped end of a platinum-wire, with a drop
of solution of cobaltous nitrate, and heating in the non-luminous
flame, when a green color will be imparted to the bead. If the
hydrogen sulphide has produced no precipitate in the alkaline
solution, then another portion of the latter is supersaturated with
hydrochloric acid, and subsequently made slightly alkaline with
ammonia water, when an ensuing transparent, flocculent precipi-
tate will indicate aluminium; this may be confirmed by moisten-
ing the precipitate, on the looped end of a platinum-wire, with a
drop of soluticm of cobaltous nitrate, and heating in the non-lumi-
nous flame, when a blue color will be imparted to the bead.
(b) The precipitate, undissolved by solution of sodium hydrate,
as directed under (a), may contain the oxides or hydrates of iron,
manganese, and uranium, the phosphates and oxalates of the alka-
line earths, calcium fluoride, and possibly traces of zinc. It is
redissolved in dilute hydrochloric acid, ammonium chloride added,
and subsequently ammonia water in slight excess. By this means
the above-mentioned metals are again precipitated, with the excep-
tion of manganese and zinc, which remain dissolved, and are
separated as follows: From the ammoniacal solution the manga-
nese and zinc are again precipitated by ammonium sulphide; a
portion of this precipitate is heated, on platinum-foil, with a mix-
ture of potassium nitrate and exsiccated sodium carl3onate, when
a green color of the fused mass will indicate mauganese; the
remaining portion of the precipitate is dissolved in hydrochloric
acid, sodium acetate in excess added, and the solution subse-
quently saturated with hydrogen sulphide, when an ensuing white
precipitate will indicate xino.
58 MANUAL OF CItBMICAL ANALYSTS.
The precipitate, as above obtained by the addition of ammoniilm
chloride ana ammonia water, is digested with a concentrated sohi-
tion of ammonium carbonate, when uranium and cerium will be
dissolved.
Uranium is recognised by a brown precipitate on supersaturating
the solution with bydroohlorio acid, and the subsequent addition
of potassium fcrrocyanide.
Cerium is recognized by the formation of a difficultly soluble
double salt with potassium sulphate. The precipitate which
remnins undissolved by the above treatment with concentrated
solution of ammonium carbonate, is dissolved in dilute hydro-
chloric acid, and the solution tested, io scpiirate portions, as
follows :
Iroo is recognized by a blue precipitate on the addition of solu-
tion of potassium fcrrocyanide.
Barium or strontinin by a white precipitate on the addition of
solution of calcium sulphate.
CaloiTUn bv a while precipitate on the addition of sodium ace-
tate, in slight excess, and solution of ammonium oxalate.
Olagnefliam,— Sodium acetate, in slight excess, is added lo the
solution, and subsequently ferric chloride until a red coloration is
produced. The liquid is then heated to boiling, fillereil, and the
filtrate completely precipitated by ammonium carbonate. The
filtrate from the latter precipitate is finally tested with ammonium.
pho.sphate, when an ensuing white, crystalline precipitate will
indicate magnesium.
Phosphoric Acid is recognized by an ensuing white precipitate of
ferric phosphate, when to the cold solution sodium acetate, in
slight excess, and subsequently a few drops of solution of ferric
chloride are added; or, if on the addition of solution of ammo-
nium molybdate iu nitric acid, and geutly heating, a yellow, crys-
talline precipitate is produced.
Oxalic Acid, as calcium oxalate, is recognized, when on the addi-
tion of sodium acetate, in slight excess, a white precipitate is
formed, which is 'insoluble in acetic acid, and by ignition is con-
verted into calcium carbonate.
Fluorine, which may be present as calcium fluoride, must be
tested for with the original substance, and may be recognized by
the etching produced upon a glass plate, which is partially cov-
ered with wax, and placed over a lead or platinum capsule in
which a little of the substance is heated with concentrated sul-
phuric acid.
(O) The portion of the ammoninra sulphide precipitate, insoluble
in cold dilute hydrochloric acid, may consist, as stated under (ft),
of the sulphides of cobalt and nickel, or simply of sulphur. If
the latter alone is present, it may be recognized by its color, as
also by its complete volatilization when heated on platinum-foil.
The sulphides of cobalt and nickel are black, and may be sepa-
QUALITATIVE CHEMICAL ANALYSIS. 59
rated by the following method : The precipitate is dissolved in
nitro-hydrochloric acid, the solution evaporated, and the residue
taken up with water containing a little acetic acid. To this solu-
tion potassium nitrite in considerable quantity is added, and
allowed to stand for several* hours, when cobalt will be completely
separated as a yellow, pulverulent double salt, whilst nickel re-
mains in solution, and may be precipitated therefrom on the
addition of sodium hydrate, as light green colored nickel hydrate.
The metals thallium and indium, which also belong to this group,
are of such rare occurrence that when their presence may be
reasonably suspected they must be tested for by means of the
spectroscope.
aronp IV.
Filtrate No, 3, page 56, is supersaturated with hydrochloric
acid, and heated until the odor of hydrogen sulphide has entirely
disappeared; when cold, it is filtered, slightly supersaturated with
ammonia water, and ammonium carbonate in slight excess added.
If no precipitate is formed on the addition of these reagents, the
solution may be further examined as directed under group V.
If, however, a precipitate is obtained, it is collected and washed
on a filter, and the filtrate therefrom, which may be marked No. 4,
reserved for the examination of bases of group V. The precipi-
tate, marked No. 4, which may contain barium, calcium, or stron-
tium, is examined as follows : It is dissolved in dilute hydrochloric
acid, and to a portion of the solution a saturated solution of cal-
cium sulphate is added. If a precipitate is formed at once, it will
indicate the presence of barium ; but if the precipitate is only
formed after standing for some time, strontium is indicated, whilst
if no turbidity is produced, only calcium can be present. In the
latter case ammonia water, in slight excess, and ammonium oxalate
are added to another portion of the dilute hydrochloric acid solu-
tion, when, if calcium is present, a white precipitate of calcium
oxalate will be produced. If calcium has thus jpecn found to be
present, the dilute hydrochloric acid solution first obtained is exactly
neutralized with ammonia water, and solution of neutral potassium
chromate added, when barium will be precipitated as yellow
barinm chromate. To the filtrate from the last-named precipitate
dilute sulphuric acid is added, and allowed to stand for some time,
when strontium will be precipitated as white Strontium sulphate.
The filtrate from the latter, on the addition of ammonia water, in
slight excess, and afterward of ammonium oxalate, will yield a
white precipitate of oaloiom oxalate.
Oronp V.
Filtrate No. 4, page 59, may still contain magnesium, sodium,
potassium, lithium, and ammonium.
60 MANUAL OF CUBMICAL ANALYSIS.
Magnesium is recognized by an ensuing white crystalline pre-
cipitate of ammonio- magnesium phosphate on the addition of
solution of ammonium phosphate.
The methods employed for testing the filtrate for potaasium,
sodium, and lithium are subject to some variation in their appli-
cation, and depend upon the previously determined presence or
absence' of magnesium. If the solution contains no magnesium,
it may be evaporated to dryness, the residue ignited to expel
ammonium salts, and the final residue dissolved in a small amount
of water. It is then examined on platinum-wire in the non-
luminous flame, to which BOdium imparts a yellow, potassilim a
violet, and lithium a carmine-red color ; the detection of potassium
in the presence of so<lium being efltected by observing the flame,
through blue cobalt glass. For the verification of potassium the
remainder of the solution may be tested with a few drops of pla-
tinic chloride; a yellow crystalline precipitate of potassio-platmic
chloride will be formed, if potassium be present.
For the special detection of lithium, the dry mixture of the
chlorides is digested with a mixture of about equal parts of alco-
hol and ether, filtered, and the filtrate allowed to evaporate spon-
taneously ; the residue from the alcohol-ether solution will contain
all the lithium, which may be recognized wlien examined on
platinurn-wire in the non-luminous flame.
If, however, magnesium has been found to be present, it has to
be first removed before potassium, sodium, and lithium can be
tested for. The solution is accordingly evaporated to dryness,
ignited to expel ammonium salts, and the residue taken up with
water. To the filtered liquid, solution of barium hydrate is added
until alkaline to test-paper, again filtered, and the excess of barium
in tlie filtrate removed b^^ solution of ammonium carbonate to
which a little ammonia water has been added. The filtrate from
the latter precipitate is evaporated to dryness, gently ignited, and
the residue tested for potassium, sodium, and lithium as above
described. In case lithium is absent, the filtrate from the above-
mentioned amrrtonio-magnesium phosphate precipitate may be
directly employed for the ordinary flame tests for potassium and
sodium.
Ammonium is always sought for in a separate portion of the
original substance or solution, by heating with a concentrated
solution of potassium or sodium hydrate; any ammonium com-
pound evolves the characteristic odor of ammonia gas, which
changes moistened red litmus-paper to blue, and produces white
fumes when a glass rod, moistened with acetic acid, is held over
the orifice of the test-tube.
Minute traces of ammonia may be detected by conducting the
vapors into a test-tube containing a small quantity of distilled
water ; if ammonia be present a brown precipitate will then be
QUALITATIVE CHEMICAL ANALYSIS. 61
produced on the addition of a few drops of solution of potassio-
mercuric iodide with potassium hydrate (Nessler's reagent).
II. EXAMIXATIOX FOR ACIDS.
The examination for the bases is followed by that for the acids and
for chlorine, iodine, and bromine. The preliminary examination,
as well as the nature of the substance ana the bases found therein,
will give information, in most cases, as to what acids cannot be
contained in the substance, and what acids may be present therein,
or should especially be looked for. Thus the acids of arsenic,
chromic and carbonic acids, and hydrogen sulphide, have already
been indicated. With soluble substances containincr earthy and
metallic bases, the presence of carbonic, phosphoric, boric, and
oxalic acids, is excluded; soluble substances, containing silver,
lead, and mercurous compounds, exclude chlorine; soluble sub-
stances, containing lead, barium, strontium, and mercurous salts,
exclude sulphuric acid.
In the examination for acids, a neutral solution is frequently
required, and generally ammonia water is used for neutralization ;
but, as most of the heavy metals, as well as some alkaline earthy
salts, are precipitated when their solutions, are neutralized by
ammonia water, it is often necessary to remove from the solution
all metals, exce|)t those of the alkalies, before proceeding to search
for acids. When this is not necessary, it is frequently requisite,
according to the nature of the substance and its chemical rela-
tions, to s?ubstitute, instead of hydrochloric acid and its salts, nitric
acid and the corresponding nitrates.
The general reagents employed in the examination for acids are
barium chloride or nitrate, calcium chloride, magnesium sulphate
or chloride, ferric chloride, argentic nitrate, and indigo solution.
By these reagents the more commonly occurring acids may be
divided, analogously to the bases, into certain groups, but, unlike
the latter, the perfect separation of the individual acids embraced
in the different groups cannot thus be effected. .
I. Acids which are precipitated by barium chloride or nitrate,
{a) From acidulated solutions: sulphuric acid as a white pre-
cipitate, insoluble in nitric or hydrochloric acids.
(i) From neutral solutions (the precipitate being soluble in acids):
sulphurous^ phosphor Otis ^ phosjfhoric^ carbonic^ silicic, boric, arsenious,
and arsenic acids, as white precipitates, and chromic acid as a yellow
one, all soluble in hydrochloric acid. Of the organic acids, oxalic
and tartaric also produce white precipitates, but only from more
concentrated solutions, and likewise soluble in hydrochloric acid.
62
UANUAL OF CUGMICAL ANALYi^lS.
II. Acids Xfbkh are. jvcipilated by cakivm chloride.
(o) From neutral solutions only: phosphoric, arsenic, and ion'c
acids as white precipitates, which are readily soluble in ammo-
nium chloride ; carlionic and sulphurous acids, as white precipitates,
but the latter one only in coneentrated solutions; tartaric acid, as
a white precipitate, soluble in ammonium chloride or potassium
hydrate, which alkaline solution becomes turbid on healing ; citric
acid gives a white precipitate, upon the subsequent addition of
lime water or ammonia water in excess, and heating; ferrocyan-
ides produce gradually a yellowish precipitate. All of the above
precipitates are readily soluble in acetic acid, with the exception
of that of ferrocyan ides, which is difBcultly soluble.
(t) From neutral or acetic acid solutions : oxalic acid, as a white
precipitate, insoluble in ammonium chloride; this precipitate is
also formed with a saturated solution of calcium sulphate; sul-
phuric acid gives a white precipitate, except in very dilute solu-
tions, when it is only produced on the subsequent addition of alco-
hol; hydrofluoric acid produces a white gelatinous precipitate,
which has the property of etching a glass plate, placed over a
lead or platinum capsule, in which the precipitate is gently heated
with concentrated sulphuric acid.
HI. Acids which are precipitated ly magnesitnn sulphate or chloride
in the presence of ammonium chloride and ammonia water.
/*/ios/)Aoricacid, as a white crystalline precipitate, whichds slowly
formed in very dilute solutions, and soluble in all acids; arsenic
acid yicldx a precipitate which is precisely analogous in its char-
acter to that of phosphoric acid, but from its acid solution, on
warming, hydrogen sulphide precipitates yellow arsenic sulpbide ;
tartaric acid gradually yields a white precipitate in concentrated
solutions, which becomes black on drying, and subsequent incin-
eratioQ upon platinum- foil.
IV. Acids which are delected ly ferric chloride.
(n) Those uhic/t are precipitated.
(From neutral or acetic-acid solutions.)
Ferrocynnides yield a blue precipitate, which is also produced
in the presence of free hydrochloric acid ; phosphoric acid, a yel-
lowish-white one, insoluble in acetic, but soluble in hydrochloric
acid; arsenic acid gives a precipitate which is analogous in \ts
properties to phosphoric acid, but is also precipitated from its
warm acidulated solution by hydrogen sulphide; lanmc acid, a
bluish-black precipitate, and the original solution is precipitated
by gelatin.
acid, a H
pitated M
QUALITATIVE CHEMICAL ANALYSIS. 63
(From neutral solutions only.)
Boric acid yields a yellowish precipitate ; benzoic and succinic
acids, light brown ones; the latter is also precipitated by a mix-
ture of ammonia water, barium chloride, and alcohol.
(J) Those which produce a coloration^ but no precipitate^
(In the presence of free hydrochloric acid.)
Ferricyanides produce a brownish coloration, and with ferrous
salts a blue precipitate; sulphocyanides^ an intense blood-red
coloration, which disappears on the addition of mercuric chloride.
(In neutral solutions only.)
Acetic acid, a reddish-brown coloration, and, on boiling, a red-
dish-brown precipitate, whilst the solution becomes decolorized ;
formic acid gives also a reddish-brown coloration, but the original
solution reduces silver and mercury from a solution of their salts ;
sulphurous acid, a reddish-brown coloration, which disappears on
boiling the solution, without a precipitate being producea; meco-
nic acid, a blood-red coloration, remaining unchanged on the
addition of solution of auric chloride ; gallic acid, a black colora-
tion, but the original solution is not precipitated by gelatin;
salicylic acid produces a deep violet coloration.
V. Acids which are precipitated by argentic nitrate,
(a) Only from neutral solutions (the precipitate being soluble in
dilute nitric acid): phosphoric acid (ortho) produces a yellow pre-
cipitate, and is also precipitable by magnesium mixture; pyrophos-
jt)Aor?'cacid, a white precipitate; metaphosphoric acid, likewise a white
one, but the free acid also coagulates albumen, which distinguishes
it from the preceding ; phosphorus and hypophosphorus acids give
white precipitates, which soon change to black ; carbonic acid, a
white precipitate; arsenic acid, a reddish-brown one, and is also
precipitable by magnesium mixture, and from a warm acidulated
solution by hydrogen sulphide ; arsenious acid, a yellow precipi-
tate, and is also precipitable from an acid solution by hydrogen
sulphide; chromic acid, a brownish-red one, and the original
yellow or red compound is changed by sulphurous acid to green;
boric acid gives a white precipitate, and, after the addition of sul-
phuric acid to the compound, the alcohol flame is colored green ;
sulphurous acid, a white precipitate, becoming blackened on heat-
ing; hyposulphurous acia, a white precipitate, soon changing to
black, and soluble in an excess of a solution of the ensuing hypo-
sulphite ; oxalic acid, a white precipitate, insoluble in acetic acid ;
tartaric acid, a white precipitate, becoming black on heating;
citric acid, a white precipitate, changing to black by the action of
64 MANUAL OP CHEMICAL ANALYSIS.
light; formic acid, a white precipitate, becoming black on heat-
ing ; salicylic acid, a white precipitate ; gallic and pyrogaUic acids
produce a separation of metallic silver; acetates and lemoates^ in
concentrated solutions, produce white crystalline precipitates,
soluble in hot water.
ip) Also from acid solutions (the precipitate being insoluble in
dilute nitric acid): hydrochloric acia produces a white curdy pre-
cipitate, soluble in ammonia water and sodium hyposulphite;
hydrolromic acid, a white precipitate, and the original solution
imparts a reddish-yellow color to carbon bisulphide, when agitated
therewith after the addition of a little chlorine water; hydriodic
acid, a yellowish precipitate, insoluble in ammonia water, and the
original compound imparts a violet color to carbon bisulphide, or a
blue color to mucilage of starch, when agitated therewith after the
addition of a little chlorine water; hydrocyanic acid, a white pre-
cipitate, soluble in ammonia water and sodium hyposulphite, and
the original compound, on the addition of a solution of potassium
hydrate, a ferrous and ferric salt, and of hydrochloric acid in
slight excess, i)roduces a precij>itate of Prussian blue; sulpho-
cyanides^ a white precipitate, difficultly soluble in ammonia water,
and the original solution produces with ferric chloride a blood-
red coloration ; sulphides^ a black precipitate, insoluble in ammo-
nia water, which is also produced in solutions of lead and copper
salts; /W/c acid, a white precipitate, soluble in ammonia water,
from which solution sulphurous acid precipitates argentic iodide;
ferrocyanideSy a white precipitate, insoluble in ammonia water,
and the original compound gives with ferric salts a precipitate of
Prussian blue: ferricyanides, a reddish-brown precipitate, and the
original solution gives with ferrous salts a deep blue precipitate.
VI. Acids which decolorize indigo solution.
Free chlorine and bromine, and their oxygen acids, when free;
free nitric acid, if not too dilute, and alkaline sulphides. On the
addition of sulphuric or hydrochloric acids^ and heating, indigo
solution is also decolorized by all chlorates, bromates, iodates, and
nitrates, and, on the addition of hydrochloric acid and heating,
besides all the foregoing acids, also by chromates, permanganates,
and all peroxides.
By the application of these group reagents the identity of many
acids can often be determined ; but, should this not be the case,
the investigation may be further continued according to the fol-
lowing method: The preliminary examination of the substance
will have shown whether it be soluble in water, either alone or
by the aid of an acid, or whether, in order to effect its solution,
the process of fusion with an alkaline carbonate must be resorted
to. According to this deportment of the substance towards sol-
QUALITATIVE CHEMICAL ANALYSIS. 65
vents, the three following divisions may be made, which are also
of service in defining the nature of the acid, and render its iden-
tification possible. Many of the known acids, and particularly of
the organic acids, being of rare occurrence, only those will be
taken into consideration which are more commonly met with in
analysis, or which are of practical importance.
A. The substance is xcholly or partially soluble in waterl
If a portion of the substance, when heated on platinum -foil,
becomes blackened, or emits combustible vapors, organic acids
should be sought for. Chromic, arsenic, and arsenioos acids will
already have been found in the examination for bases, groups II.
and ill. Carbonates and snlphides will be recognized by the de-
velopment of gas bubbles when dilute hydrochloric acid is added
to a portion of the liquid ; the former produces a white precipitate
when the gas is led into lime-water, and the latter may be recog-
nized by the odor, as also by the blackening of a strip of paper,
previously moistened with a solution of lead acetate, and placed
in contact with the gas.^ Tannic, gallic, benzoic, snccinic, and
acetic acids, and ferrocyanides, may be detected by the addition
of a little neutral ferric chloride to the solution, and discriminated
from each other as indicated on pages 62 and 63.
(a) A portion of the original solution is acidulated with hydro-
chloric acid ; if this produces a precipitate, it is separated by
filtration, and the filtrate is made slightly alkaline with ammonia-
water; in case this should produce a precipitate, it is again fil-
tered, and the filtrate finally tested with barium chloride. A
precipitate with barium chloride will indicate, in the absence of
organic acids, either sulphnric, boric, phosphoric, or silicic acids;
the precipitate with sulphuric acid is insoluble in nitric or hydro-
chloric acids; boric acid in the free state, or mixed with con-
centrated sulphuric acid when in the form of a salt, imparts a
green color to the alcohol flame; phosphoric acid, in neutral solu
tions, gives with argentic nitrate a yellow precipitate, soluble in
nitric acid or ammonia-water, and with magnesium mixture, a
white crystalline precipitate of ammonio-magnesium phosphate;
very small amounts of phosphoric acid are detected by heating
with a solution of ammonium molybdatc in dilute nitric acid,
when a yellow crystalline precipitate will be instantly ])roduced ;
silicic acid and its salts, with the exception of those of the alkalies,
are insoluble in water, and may be detected by evaporating a
portion of the solution to dryness, and taking up the residue with
water containing a little hydrochloric acid, when the silica will
remain behind as an insoluble powder. If organic acids are pre-
sent in the original solution, the precipitate produced by barium
chloride may also indicate cxalic, tartaric, and citric acids, and
these, in neutral solutions, likewise produce white precipitates
6
66 MANUAL OF CHEMICAL ANALTSTS.
with argentic nitrate, which are soluble in ammonia-water and in
nitric acid. They may be distinguished as follows: oxalic acid,
upon the addition of lime-water in excess, yields at once a pre-
cipitate, insoluble in acetic acid ; tartaric acid yields a precipitate,
soluble in acetic acid ; citric acid aftbrds no precipitate until the
liquid is boiled, and the precipitate is soluble in acetic acid. Beside
the acids already mentioned as producing precipitates with a neu-
tral solution of barium chloride (a), page 60^ may be added
chromic, carbonic, arsenious, and arsenic acids ; but, as previously
stated, these acids would also be found in the examination for
bases, and may thus be readily identitied.
{b) A portion of the original solution is acidulated with nitric
acid, and solution of argentic nitrate added, when a precipitate,
insoluble in dilute nitric acid, will indicate hydrochloriOy hydriodiOi
hydrobromio, and h3fdrooyanic acids, as also ferrocyanides, fiarri-
cyanides, sulphocyaiddes, and sulphides, all of which may be dis-
tinguished from each other Vjy the reactions given on page 64, V. (5).
(c) A portion of the original solution is tinted faintly blue Avith
indigo solution, and a little concentrated sulphuric acid added and
heated. Ensuing deeolorization will indicate nitric, chloric, or
hypoohlorous acids, as also fi^ee chlorine. Nitric acid may be
readily detected by adding to the solution to be tested, contained
in a test-tube, concentrated sulphuric acid, cooling the mixture,
and then ciirefully ])ouring upon the surface of the liquid a solu^
tion of ferrous sulphate, so as to form two distinct layers (Fig. 34);
a brown or violet coloration of the liquid, or a brownish colored
zone at the point of contact of the two liquids will then be pro-
duced ; chloric acid, besides being indicated, together with nitrates,
QUALITATIVE CHEMICAL ANALYSIS. 67
in the preliminary examination, page 47, is also recognized in its
salts by strongly heating, when it is reduced to chloride, and may
then be tested by argentic nitrate.
Of the more commonly occurring acids, only aootiOy SOlphuroas,
and hydrofluoric acids still remain ; these have already been men-
tioned, and may be recognized by the distinctive tests of the
preceding group reagents, as described on pages 61, 62, and 63.
B. The substance is insoluble in water, but soluble in acids,
A portion of it is heated on platinum-foil, to ascertain the pre-
sence or absence of.orgaiiic acids.
(a) The powdered substance is treated with nitric acid, and
heated; oarDOnio acid may be recognized by effervescence, and
by the formation of a white precipitate when the evolved gas is led
into lime-water; violet or brown vapors will indicate iodine and
bromine, which may be recognized by a purple or yellowish color-
ation of chloroform or carbon bisulphide, when shaken with a
small part of the dilute nitric acid solution.
{b) To a portion of the nitric acid solution, solution of argentic
nitrate is added, when a white precipitate, insoluble in nitric acid
but soluble in ammonia-water, will indicate hydrochloric acid.
(c) A portion of the substance is boiled with a solution of potas
sium carbonate, and filtered ; a few drops of a solution of a ferrous
and ferric salt are then added, and subsequently hydrochloric
acid in slight excess, when a blue precipitate will indicate hydro-
cyanic acid.
(d) A portion of the substance is dissolved in hydrochloric acid,
and solution of barium chloride added; a white precipitate, in-
soluble in water, or in an excess of hydrochloric or nitric acids,
will indicate BUlphnrio acid.
(e) Boric, silicic, and hydrofluoric acids may be recognized in
the preliminary examination, and by previous mentioned tests
(pages 61, 62, and 65); phosphoric and oxalic acids, if in combination
with alkaline earths, would have been found in the examination
for bases, page 58; if combined with metallic oxides, they should
be tested for in the liquid from which the bases precipitable by
hydrogen sulphide and ammonium sulphide have been previously
removed.
(/) A portion of the substance is dissolved in hydrochloric
acid, ammonia-water in slight excess added, and, in case a pre-
cipitate is produced, filtered therefrom. Solution of calcium
chloride is tnen added to the filtrate, when a precipitate, soluble
in acetic acid or potassium hydrate, will indicate tartaric acid ;
if the precipitate is formed only after boiling the solution, then
citric acid is present ; if the precipitate produced in the cold solu-
tion is insoluble in acetic acid, and also produced in the ammo-
niacal solution by the addition of solution of calcium oxalate, then
oxalic acid is present.
MANUAL OF CHEMICAL ANALYSIS.
C. The suhstance is ivsolvhlf, or onh/ partially soluble in aeida.
The substance, or portion of ihv substance, insoluble in acids,
may be best brought into a condition suitnble for further exami-
nation by mixing it inlimatcly with four parts of dry sodium
carbonate, and fusing at a red heat. The fueed mass, when eold,
is boiled with water, and the solulion filtered from the insoluble
renidut'. To the solution nitric acid is udded in slight excess;
solpludeB will be recognized by the odor of the developed gas,
unci by imparting a black slam to najHT moistened with lead
acelate. l!' a precipitate is produced by the addition of nitric
ucid, it may consiat of silicic acid, and is coHected upon a filter
for further examination; in the latter case the solution may also
contain some silica, and a portion of it is evaporated to dryness
with strong hydrochloric acid, and the residue taken up with
water acidulated with a little hydrochloric ncid, when silica will
remain behind as an insoluble powder. To a portion of the origi-
nal solution, acidulated with nitric acid, solution of argentic
nitrate is added, when a white precipitate, insoluble in excess of
nitric acid, and soluble in ammonia- water, will indicate liydro-
olilorio acid; the foriniition of a white precipitate on the addi-
tion of barium chloride to the acidulated liquid will indicate snl-
phnrlo acid. Boric and hydrofluoric acids may be recognized by
previously indicated tests, pages 61 and C2 ; phoapborio acid is
recognized on the addition of ammonium uiolylxlate to the nitric
ncid solution, and gently heating, by the production of a yellow
crystalline precipitate, insoluble in nitric acid, and soluble in
ammonia-water; or by the yellow precipitate produced in the
carefully neutralized solution on the addition of argentic nitrate,
as also by a white crystalline precipitate on the addition of magne-
sium mixture. It should, however, be remembered that arsenic
acid produces with ammonium raolybdate, and magnesium sul-
phate in ainmoniacal solution, precipitates precisely analogous to
those of phosphoric acid; the arseiu'c acid may be readily recognized
by its reaction with argentic nitrate, or by saturatinij the warm
sohition with hydrogen sulphide, when arsenious sulphide and
sulphur will be precipitated.
If the solution, as above obtained, by boiling the fused mass
with water, shall have been found to contain nothing more than
the excess of tlie applied sodium carbonate, then the entire fused
mass may be treated with dilute nitric acid, and the solution
thus obtained examined for the above- monlioiicd acids, in the
manner already indicated.
Tliis outline of a systematic course of analy.sis, although neces-
sarily open to moditiaation in some of Its details, such as mar
frequently be indicated by the results of the preliminary exami-
nation, and of that for base?, wilt, it is believed, for tho.'ie possess-
QUALITATIVE CHEMICAL ANALYSIS.
69
ing ordinary chemical knowledge, be found a reliable and trust-
worthy guide, whenever recourse has to be taken to such a method
in the examination and identification of medicinal chemicals, and
the more commonly occurring chemicals used in medicine, and in
the arts and trades.
TABLE
OF THE DEPORTMENT OF THE COMPOUNDS OF THE PRINCIPAL METALS
WITH SOME OF THE GENERAL REAGENTS.
Precipitable by Hydrogen Sulphide
From Acid Solutions : From Alkaline Solutions :
as Sulphides : as Sulphides : as Hydrates :
As Sb Sn Mo Au Pt Pd Fe Mn Co Ni Al Cr Ce.
Bi Ag Cu Pb Cd. Zn Ur Tl In.
Nitric Acid :
Pb Bi Cu Ag Cd Fe
Ma Zn Ur TI In.
Sulphides soluble in
NitrO'hydrochloric Acid :
Hg Co Ni.
Ammonium Sulphide :
As Sb Sn Mo Au Pt
Hydrochloric Acid
Precipitable by
Sulphuric Acid:
Pb Ag Hg,0. Pb Hg Sb Sn Ba Ca Sr.
Ammonium Carbonate: Water:
(in the presence of
ammonium chloride)
Ba Sr Ca, Bi Hg,0 Sn Sb.
Ammonia- Water :
(soluble in excess)
Zn Cu Cd Ni Co
(insoluble in excess)
Pb Bi Hg Fe Sn Sb Mn
AlCr.
Potassium Hydrate:
(insoluble in excess)
Cu Cd Ni Co Bi Hg Fe Mn
(soluble in excess)
Pb Sn Sb Zn Al Cr
(re-precipitated by boiling)
ZnCr.
Hepropt.
OOOfEE MEDICAL COLL:w«»
•AH fRANCISCO. OAU
Kflrf 4m not to lie remtfi'Mi /mm tha
Jtibrnm /'[■/) J'fti I )r,;-Mirt or
H'.lii,-,h (;■■■..■. , .
VOLUAIETRIC ANALYSIS.
The quantitative estimation of a number of medicinal chemi-
cals and their preparations has been much simplified in practice
by the volumetric method of chemical examination, which is based
upon the fact thai chcm'cal subacinces combine in definite and
equivalent proportions, and consists in noting the volume of a
test-solution of known strength, required to profluce b_v chemical
reaction a certain visible effect when added to a known quantity
of the substance under exiimination. On obtaining this effect, the
quantity of the reagenl being ascertained,
Fio. SB. and that of the substance being already
known, an accurate estimate may readily
be made by equation and simple calcula-
tion.
By the aid of this Bimple and rapid
mode of examinatiou, the proportion of
the constituents of many chemical com-
pounds and their preparations may be at
once quantitatively estimated. In the fol-
lowing part of this volume, in treating of
nil those chemicals and preparations in
which a quantitative determination of the
principal constituents is required, and to
which the volumetric mode of examina-
tion is best suited, either alone or as &
confirmatory test, reference lias frequently
been made to these pages in explanation
of the proceSHCs involved ; and in connec-
tion with which, fur many substances, is
also stated the quantity of the volumetrio
test solution requisite to produce, with a
definite weight of the substance under ex-
amination, indirect relation or correspond-
ing to its molecular weight, the exact re-
action indicative of its olBcinal strength. In treating of the vari-
ous chemicals in the following pages of this volume, where special
volumetric methoris of analysis are indicated for their examina-
tion, or when for those methods here given a more detailed desorip-
VOLUMBTBrc ANALYSIS.
n
tion of the procesa may 'jo considered necessary or desirable, the
inrthod of procedure will in all cases be fully explained.
Tlie apparatus required for volumetric analysis consists, besides
the common utensils, as beakers, funnels, porcelain-capaules, cru-
cilileH, stirring-rods, balances, etc., of one or several liter-flasks
for the preparation of tlio test -aol lit ions (Fig. 3o); these, when
filled to a mark on the neck, have mostly a capacity of 1000 cubic
centimeters (1 liter) of distilled water at the temperature of 15° C.
(59° F.); Home cylindrical graduated liter-jars (Figs. 36 and 37),
Fig, 90.
divided into 100 or 1000 oeutimeter-parts, and used for the pre-
paratioQ of test-solutions as well as lor the admixture of parts
of a liter; and one or several graduated tubes for the delivery
nod measurement of the test-solutions;, pipettes and burettes.
The pipettes (Figs. 33, 3!), and 40) are provided either with a
VOLUMETRIC ANALYSIS,
78
BuretteB are preferable for delivery and measurement, and are
now quite universally employed; tbey hold to ii certain mark 100
or less cubic centimetera, and are divided by graduation into a
corresponding number of equal parts. There are tbree kinds of
burettes in use, wliicli differ mainly in tiieir construction for deliv-
ery : Mohr's burette, Gay Lusaac'a burette, and Geissier's burette.
or tbese. Mohr's burette {Figs. 41 and i'2), on account of its
cheapness, simplicity, and convenience, is now in general use for
the more common purposes, but its application is excluded in the
employment of such solutions aa would be aftected by contact
with rubber tubing, as in the case of potassium permanganate,
silver, or iodine aolutions. It consists of a graduated glass tube,
74
MANUAL OF CHEMICAL ANALYSIS.
of about 12 millimeters (half an inch) internal diameter, and 50
centimeters (twenty inches) in length; to its contracted lower
extremity is fitted a small piece of rubber tubing, into the lower
end of which a small piece of glass tubing, about 25 millimeters
(one inch) in length, and drawn out at the lower orifice to quite
a fine point, is tightly inserted. A strong wire clamp (Fig. 43)
Fig. 43. Fio. *
closes the rubber tube, so that the fluid can only
pas.t through, either in a stream, or drop by drop,
when the knobs of the clamp are pressed. Since the
oorrectnesa of the tcBt depends upon the accurate
reading of the height of the test-solution in the
burett«, a small hollow glass float, known as Erd-
mann'a float, is sometimes employed for this purpose
(Pig. 44); it is of such a diameter that it can move
freely in the tube without undue friction, and of
such a weight that it sinks to more than half its length in the
test liquid. A line is scratched around the centre of the float,
serving to mark the coinciding line on the burette, and not the
actual height of the liquid contained therein, which does not
require consideration.
The application of the float for determining the exact volume
of test liquid employed is subject to certain restrictions; the
burette must be accurately calibrated, f(Jr, if in the least ununi-
form in caliber, the reading in the narrow and wider jKirtions of
the tube will not agree with the direct reading by means of the
marks on the burette. As usually construcleci, the mercury
contained in the lower end in order to give it the pro]ier weight
is also liable to oxidation, which then disturbs the transparency
of the inlerior of the bulb, and renders the line on the opposite
side either invisible or indistinct ; also in the case of highly colored
solutions, as potassium permanganate, iodine, etc., the fine line en
the float is seen with difficulty, or not at all. For these reasons
the float is not very generally employed, and the readings may
usually be attaiueJ with sufficient accuracy, and with but slight
error, by observing, in the case of colorless liquids, simply the
murk on the burette coinciding with the lower line of the concave
menisoua of the liquid when held towards the light ; with colored
VOLUMETRIC ANALYSIS. 75
liqnidB the lower line produced by the concave surface of the
liquid is not so distinctly seen, and in this ease it is therefore
better to observe the mark on the burette coinciding with the
upper line of the concave surface when held from the light, or
Against a dark object, by which means readings proportionately
accurate may readily be obtained.
Other forms of Mohr's burette are provided with a glaaa stop-
cock (Figs. 4o aud 4(1), so as to be suitable for all liquids, iaelud-
>
ing those which are al^ected by organic matter ; they are, however,
more expensive than the one above described, and in the hands
lb MANUAL OP CHBMICAL ANALT5IS.
of the iiiexperionce<i are less convenient, as also not permitting
an ennally ready control over the tiow of liquid.
Gav Lussac's burette is rejiresonted in Fig. 47. This ia one of
the oldest forms of burette, and is still in quite frequent use, as
being composed entirely of glass it may be used for estimations
with any of the volumetric test-solutious, and is thus not open to
the objections of the simple form of Mohr's burette. The burette
is graduated from a point somewhat below the point of delivery
downward, and has usually a capacity of 50 cubic centimeters
to the lowest point of graduation, subdivided into tenths of a
cubic centimeter. In usiug the burette it is most conveniently
held in the left hand, and so inclined as to allow thu te-it-liquid to
fall drop by drop into the solution of the substance to be esti-
mated, contained in a beaker or other vessel, meanwhile stirring
the liquid wilh a glass rod held in the right hand. When the
liquid does not flow readily from the exit tube, it may be facili-
tated by protlucing a slight pressure with the mcuth by means of
a piece of glass tubing inserted in the cork of the burette, or
preferably by means of & small piece of rubber tubing attached
to the glass tube; in no case should tlie liquid come in contact with
the cork. In observing the height of the liquid in the burette it
should be held near the top by means of the thumb and fore6ngep
of the right hand, when it assumes a perfectly vertical position,
and any expansion of the liquid caused by the heat of the band is
also thereby avoided; the same rules in relation to the concavity
of the upper surface of the liquid being observed, as have been pre-
viously described.
Geissler's burette is represented in Fig. iS. It ia a modifica-
tion of Gay Lussac's burette, but differs from the latter by having
the small lube inclosed within the larger one, thereby tending
to render the btirette less fragile; this is, however, one of the
less convenient forms, and being also difficult of accurate con-
struction, ia not in general use.
Burettes are conveniently kept for ready use on a revolving
stative (Fig. 49), and should be properly labelled in accordance
with the test-solution contained therein, in order to avoid error.
To prevent the evaporation of the test-solution and exclude dust,
the burette may be closed at the top by means of a marble, as
shown in the figure, but as these are liable to fall from their
position and produce breakage of other apparatus beneath, an in-
verted short test-tube ])laced over the top of the burette ia much to
be preferred ; alkaline solutions, when kept for any length of time
in the burette, should be protected from the absorption of carbonic
acid gas by means of a tube filled with fragments of fused [)Otas-
aium hydrate, and inserted in the cork of the burette, as shown in
the figure.
The teata are made by first filling the burette with the test-solu
tion to exactly such a height that the mark on the float is coin-
cident with the 0 on the scale of the tube, or, if the float is not
employed, the mark on the burette coiiiciiliiig with tlie aurface of
the liquid conliiined therein should be accurately observed. The
solution or mixture to be tested is placed in a oeakcr under the
KAXCAL or CHSaiClL ASALTSIB.
barelle (l^g. 50), uii tbeo •>> nrodi of tfa« I _
ally attd carefnlljr delivered iDto tW beaker, with gentle etnriDg
with a glass rod, as to accoioplii-h tbe reaction indicative of the
completion of the operation.
Vylnmetric determinations are principally based, either upon
nrvlralizittion, in which the quantity of a base or aa acid is deier-
■iiiiiod by noting the volume of the Ifsi-solution of acid or alkali
whieb is necessary to convert it into a neutral salt ; the point of
neutralization being usually indicated by means of litmus solu-
tion,* which assumes with free acids a red, and with free alkalies
• Plienolplilalein biu recently been recommended as in indicAtor in alkali-
mctiy; llie n«ulm1 und acid solnlioiis of lliiii siib«l*nce being colDrless, but
AMumtog in tlie presence nrtlic sKKbleBl excetis of alkuli an intense carmine-red
culor. Tlie color developed bf alkniieB U destroyed by all adds, inclnding
carbnai«: benc<?, tike litmus, it is unliilcd for use in the titration o( CHrbonatea
III ihe cold. TiJC H)1ntion is prepared for use by dissolving one part of pUenol-
Shlatcln In 100 pHrlsofa miilurc of 35 parts of alcolinl and 75 parts of water;
>ur or five drops of this solution beiug sufficient tor 60 to 100 cubic centl-
melera of Ibe ■nlnllDn to Im tltnued.
Cochineal tolntian Is nccaaionally need in preference to litmus, particularly
wttb lotulioii* of tbe alkaline eartba, sudi sa calcium and barium hydrates, and
povMsaea tbe addltioiul advantage tbat it is tiiuch less modifled in color by tbe
prcaence of cartHiulc acid. The solution is jirepared by digesting 3 grama of
powdered cncliineal in a mixture of 40 cubic centimeters of alcohol Hnd 100
cubic centimeters of H-ntrr. Us cidor is yrlUiwIsh.red, nhicU Is changed to violet
by alkalies, lulncrul acids restoring Ibe urigiaal color ; but it is not so sen^bly
VOLUMETRIC ANALYSIS. . 79
a blue coloration ; or, upon oxidation and reduction^ in which the
quantity of the substance to be determined is found by noting the
volume of the test-solution of the oxidizing or reducing agent to
which it is equivalent, or which is required to produce a certain
reaction ; the changes indicating the final completion of the pro-
cess varying in their nature according to circumstances or the
process employed; the principal oxidizing agents being potassium
permanganate, potassium bichromate, and iodine, and the reducing
agents, ferrous and stannous salts, and sodium hyposulphite (thio-
sulphate); or, upon precipitation^ in which case the quantity of
the substance to be determined is derived from that of the re-
agent required to cause its complete precipitation, or, the reagent
is added until a precipitate begins to make its appearance, when
a certain stage in the process is thereby indicated, from which the
calculation may be made.
The quantities of the substances to be assayed volumetrically
are submitted to examination by weight, which are sometimes
for convenience in calculation made coincident with their mole-
cular weights, and are expressed in grams ;* those of the test-
solutions by measure in cubic centimeters.f
In the preparation of solutions for volumetric estimations those
designated as normal are, as a general rule, such as contain, for
univalent substances, the molecular weight expressed in grams in
one liter, and for bivalent substances, or salts containing two
atoms of a univalent base, one-half of the molecular weight ex-
pressed in grams in each liter; solutions of trivalent substances
containing one-third of the molecular weight, etc. Decinormal and
centinormal solutions are, therefore, one-tenth of this strength, and
are frequently for convenience briefly designated as — and
10 100
solutions. Solutions are, however, sometimes made of such a
strength as to be only empirically normal, and are so prepared
that a certain volume of the liquid (100 cubic centimeters) stands
in direct relation to, or will exactly neutralize, a known quantity
(one gram) of some one definite substance in a pure state, by
which means the number of cubic centimeters of the test-solution
employed for the same amount by weight of the substance to be
estimated, will indicate at once the percentage strength of the
substance under examination. Such solutions, although some-
times conveniently employed in the analysis of technical products,
affected by the weaker organic acids as litmus, and for these the Fig. 51.
latter is, tlierefore, to be preferred.
♦ One gram is equal to 15.434 grains of Troy weigiit.
t A cubic centim*{ter (Fig. 51) is the volume occupied by one
gram of distilled water at its point of greatest density, 4o C. ;
metric measurements, however, are uniformly taken at 15^ C.
(590 F.).
80
MAXllAL OP CHEMICAL ANALYSIi
are limilcc] in their applicatioQ to the estimation of one single
substiince, requiring for each aoid and alkali a special liquii],
whereas vith virtually normal Kolutioni! but one acid is required
for all bases, and one alkali fur all acids.
Solutions are sometimes designated as normal which bear no
delinite relation to the molecular weight of the substance con-
tained therein, or to its neutralizing power, but, as in the processes
of oxidation and reduction, refer to a particular reaction involved
in the process to which the solution is applied ; thus a normal
solution of potassium permanganate (K,Mn,Og) is made to contain
otie-tenth of the molecular weight expressed in grams in a liter,
with reference when used as an oxidixing agent to the amount of
available oxygen:
■2IC,Mn,0, + tJH^. - 2E,S0, + ■iMnSO, + 6H,0 + 60^
A normal solution of stannous chloride, although tin is a quadri-
valent metal, will thus likewise, when used as a reducing agent,
contain one-half, and not the fourth of its molecular weight ex-
pressed in grams in a liter, as is shown bv the expression of its
reaction with ferric chloride : Fe,Cl, + SnCl, - 2FcCI, + SiiCl,.
AITAX.TSI8 B7 NEUTRALIZATION.
ESTIMATION OF ALKALIES (ALKALIMETRY).
The operations of analysis by neutralization are based upon tha
fundamental and simple principle, that the proportions in wtich
chemical substances unite with each other in forming new com-
pounds are definite and invariable, and that these proportions are
represented by the molecular weights. In the formation of solu-
tions, ihert-fore, for volumetric estimations by neutralization, a
simple equation, and the molecular weights deducted therefrom,
will at once indicate the amount of solid substance necessarv for
the production of a normal solution, which then bears a direct
and simple relation to all other substances with which it may be
employed for neutralization, and which is expressed by the mole-
cular weight of the substance, or a corresponding fraction deducted
therefrom.
The standard test-solutions employed for the estimation of
alkalies are either oxalic or sulphuric acids; the oxalic acid solu-
tion is the more commonly employed, and is generally preferred
on (iccouiJt of the convenience of preparation, but as the amount
of water of crystallization which the acid contains (two molecules)
lias to be considered in the preparation of the solution, it is neces-
sary that it should be neither moist, nor that it should have lost a.
part of the water of crystallization by exposure — conditions which
■would materially influence the correctness of the strength of the
solution, and consequently the results of all the estimations obtained
VOLCMETRIO ANALYSIS.
81
therewith. Its action upon litmus is moreover not quite aa dec!-
flive or aa dJRtinut as that of sulphuric acid, for which reason, and
that above mentioned, sulphuric acid is considered in careful re-
search to furnish more accurate results.
For the preparation of a standard sulphuric add, 49 grams
(corresponding to one-half the molecular weight) of coaceiitrated
i^ulphuric acid are diluted with water to the measure of one liter.
This affords a solution which is approximately normal, and the
exact strength of which is afterwards determined. A burette
being filled with the acid solution, a certain number of cubic cen-
timeters are allowed to flow into a beaker, a few drops of litmus
solution added, and from another burette containing a solution of
Mtaasium or sodium hydrate of empirical or unknown strength,
but which should be stronger than tlie acid solntion, a sufficient
amoutit is added until the indications of the point of neutraliza-
tion are obtained, or until the lai^t drop of the alkaline solution
wliicli is added produces a decided blue coloration. From the
number of cubic centimeters of the alkaline solution required, as
determined by two or three experiments with concordant results,
a simple calculation will show to what extent the alkaline solu-
tion has to bo diluted in order that equal volumes of the acid and
alkali shall precisely neutral-
ize each other, and which must F'«- 53.
agam bo conlirmed by experi-
ment after tlie dilution of the
alkaline solution. This having
been attained, two or three
portions of pure, freshly ig-
nited sodium carbonate, of
about two grams each (readily
obtainable by the ignition of
portionsof pure sodium bicar-
bonate, of about three grams
each, in an open porcelain
crucible, and preserved after
ignition by filling, while e
warm, into tightly corked test-
tubes), are accurately weighed.
The several portions, dissolved
separately, in small amounts
of water, in a percolain cap-
sule or beaker, and a few
drops of litmus solution added,
are then titrated with the acid
solution (Fig. 52); the liquid
being heated from time to time
to insure the complete removal of the diseng.iged carbonic acid gas,
until a slight excess of acid has been added, which is evidenced
82 MANUAL OF CHEMICAL ANALYSIS.
by the appearance of a bright cherry-red coloration. The excess
of acid employed may be then inver.sely titrated with the alkaline
solution until the blue coloration is produced, when the amount
required of the latter, deducted from the number of cubic centi-
meters of acid employed, will give the number of cubic centimeters
of acid which were required for the exact neutralization of the
amount of carbonate taken. The number of cubic centimeters of
acid which would be required if the latter were exactly normal,
may be found by dividing the amount of sodium carbonate taken
by the decimal 0.053 (the amount of sodium carbonate equivalent
to one cubic centimeter of strictly normal sulphuric acid). This
number, which will usually be found to be somewhat greater or less
than the number of cubic centimeters employed, will, when divided
by the latter, give a number slightly greater or less than one,
showing that the acid is a little weaker or stronger than normal,
and, designated as the correction factor or coefficient, must be
used to multiply the number of cubic centimeters of acid or alkali
used in each estimation, in order to convert it into its equivalent
of normal strength. The exact strength of the acid and alkali
and their correction factor havins^ thus been accurately deter-
mined, the methods of their application remain the same as will
be described for the standard solution of oxalic acid.
S'aiulanl Solution of Oxalic Acid.
II,C,0, -h 2H,0; 12<). 63 Grams in 1 Liter.
Sixty-three grams of |)ure crystallized oxalic acid are dissolved
in water; the solution is filtered into a liter-flask, and the filter
washed with water until the exact volume of 1 liter, at about
lo^ C. (59° F.), is obtained.
One hundred cubic centimeters of this solution contain one-
twentieth of the molecular weight, in grams, of oxalic acid, and
are, therefore, capable of neutralizing one-twentieth of the molec-
ular weight in grams of bivalent bases, or salts containing two
atoms of univalent metals, or one-tenth of the molecular weight
in grams of salts containing one atom of univalent bases.
This test solution is applied for the estimation of the alkaline
hydrates, carbonates, acetates, tartrates, citrates, and borates: 100
cul)ic centimeters of the solution will exactly neutralize, or other-
wise decompose, if pure, or of officinal strength :
5.23 grams of Ammonii CaHwnnii. NH.HCO.-j-NH^NII.CO..
17.00 ** Aqna Amuinniae, U.S. P., spec. grav. 0.9.)9.
6.07 ** Aqua Ammonife fortior, U. S. P., spec. grav. 0.900.
54. (W *' Liquor Plumbi Subacelalis, U. S. P., spec. grav. 1.238.
112.00 " Liquor Potassa^. U. S. P., spec. grav. 1.036.
80.00 '' Liquor Sotlap, U. S. P., spec. grav. 1.059.
9.80 ** Polassii Acetas, KCjHjU,.*
* Alter ignition.
VOLUMBTRIO AKALYaiS. o8
10.01 grams of Pntustl Bicnrbonag. KHCO,.
1(180 ■• PnWMii Bitartrns, KHC.H,0,.»
8,30 " PniHssii Carlmnas, depur«tiis.
6.91 " Potassii Curbonas, puma, K.CO,.
10.80 •■ PotasBii Ciira», KjC.HiO,-!- tip,* or 10.90 grams of anliy-
(Iroua salt.
14.10 " PoUBsii et SoiiU Tnnnia, KSaC,H,0,-f 4H,0.»
n.fll " Poiaesli Hydras, KHO.
8.14 " PnlBssU PerniHiiganBe, K,Mn,Oa.
11.76 " PntBBsii TarlrnB. aK,C,H,0,,H,0.«
18.80 " Sodii AceUs, NaaH,0,+ 3HjO.»
8.40 " Sodii Blcarlwnas, NaHCOi.
8.B8 " Sodii Bicarbonas Venalis
10.10 " Sodii Boras, Na,B,0,-)- lOH.O,
14.30 " Bodii CarlKmaa, NajC0,4- lOH,0, or 6.8 grams of anliydrous
Fio. S3.
J. gray. 0.810.
The operation is conducted by weighing the above quantity of
the substance, or the preparation to be estimated, placing it in a
beaker, and, when required, diluting or disaoiving it by the addi-
tion of a sufficient quantity of water. The tartrates, citrates, and
acetates have first to he completely converted into carbonates by
ignition in a platinum or porcelain crucible (Fig. 53), care being
taken that no loss of substance is occa-
sioned by the increase of volume on first
heating; to avoid this, the crucible should
be sufficiently large, and at first very
gently healed, after which the heat may
be increased until inflammable vapors
cease to be evolved, and perfect reduction
ia effected. As this operation is usually
accompanied by the separation of consid- '
erable carbon, the fused mass should be
extracted with hot water, filtered into a
capsule or beaker, and the filter, together
with the insoluble residue, well washed
with water.
When the solution is ready for the test,
a few drops of litmus solution are added,
so as to impart a di.stinct bluish tint ; the
capsule or beaker is then placed under the
burette containing the test-solution (Fig. 54), and, with constant
gentle stirring with a small glass rod, the test-solution is delivered
into the beaker, first in a stream, and, when approaching the point
of neutralization, drop by drop, until the blue liquid assumes a
cherry-red hue. In the estimation of carbonates it is preferable,
as stated on page 81, to add an excess of the standard aeid solu-
tion above that required for the neutralization of the alkali, the
» After Igaition.
84 MANUAL OF CHEMICAL ANALYSIS.
Bolatiim being hciited to expel completely the liberated carbonic
acid giis, which, by its action upon HtmuM, imparls a violet or
wine-red coloralion to the liquid, as distinguished from the light
cherry-red coloration which is produced by the acid test-solution.
The excess of acid employed msiv then be inversely titrated or neu-
tralized by a corresponding standard alkali solution, the preparation
of which has already been mentioned (page 81), and will bo fur-
ther described uuder the estimation of acids; the difforenee
between the amounts of the
two solutions employed, both
being equal in volumetric
strength, will give the exact
amount of acid solution re-
quired for the neutralization
of the alkali or alkaline car-
bonate. This method of pro-
cedure has the additional ad-
vantage that ihe change of
color of the litmus solution
from red to blue is much more
prominent than from blue to
red, thus insuring a more ac-
curate determination of the
exact point of neutralization.
These operations require
care and skill in every point,
Eo as to avoid the slightest
loss of either of the liquids,
and a consequent error in the
final result.
When neutralization is in-
dicated by the light, cherry-
red coloration in tne one case,
or, in the above described
method of inverse titration, by the ap|jearaiioe of the blue colora-
tion in the other, the process is completed, and the volume of the
acid test-solution employed is observed. The number of cubic
centimeters employed, less than 100, indicates at onee the per-
centage of impurities, orof deficiency of strength in the substance
estimated.
On the other hand, each cubic centimeter of the teat-solution
of oxalic acid employed corresponds to one milligram molecule of
alkaline hydrate, one-half milligram molecule of alkaline carbon-
ate, or the proportionate amount of other salts, i.e.;
1 cubic oentlnioler correapond* lo 0.017 gmra AmmoiiU gw. NH,.
1 '• '• " " O.0S233 " Ammonium Cnrboiiiit^,
NH.l!CO,.NH,NH,CO^
I " •* '• '■ 0.18925 " Lead Acotnlc, crrstnlKzFJ,
PbtC,U,0,),+ aH,0.
VOLUMETRIC
ANALYSIS. «0
1 cubic centimeter
corresponds to 0.18675
gram Lead Subacetate, as
Pb,0(C,H30A..
Potassium Acetate, JKC,n,(X.*
Potassium Bicarbonate, KHuO,.
0.0980
0.1000
0.1880
Potassium Bitartrate,
KHC,H,0,.»
0.0690
Potassium Carbonate, anby-
drous, K^COj.
0.1020
Potassium Citrate, anbydrous,
K^C.HA*
0.0560
Potassium Hydrate, KOH.
0.0814
Potassium Permanganate,
KyMn^Og.
0.1410
Potassium Sodium Tartrate,
KNaC,H,0.+ 4H,0.»
*
0.1175
Potassium Tartrate,
0.1860
Sodium Acetate,
NaC.,HA+2H,0.»
0.0840
Sodium Bicarbonate, NaHCOj,.
0.1910
Sodium Borate,
Na,B,O7+10H,O.
0.1430
Sodium Carbonate, crystallized,
Na,C03-hlOH.,0.
0.0580
Sodium Carbonate, anbydrous,
Na.CO,.
0.0400
Sodium Hydrate, NaOH.
A simple equation will give the amount of alkaline hydrate, car-
bonate, or other salt present. By operating on 100 times the half-
milligram molecule, t. c, 6.9 grams of potassium carbonate, or 5.3
grams of anhydrous sodium carbonate, all calculation is dispensed
with ; for, as this amount, if present, would require 100 cubic centi-
meters of standard oxalic acid solution for its neutralization, the
number of cubic centimeters actually required, at once indicate
the percentage of alkaline carbonate.
On the other hand, it is sometimes preferable, instead of weigh-
ing a certain definite quantity of a salt, or of a solution, to take
any convenient quantity, and then ascertain its exact weight. This
is especially the case with liquids like ammonia-water, which, by
exposure during the time of weighing, would suffer considerable
loss by the volatilization of the gas, or, in the case of concentrated
acids, a certain loss by evaporation or absorption of moisture
would be experienced. In the latter case, whatever the number
of cubic centimeters of standard acid or alkali solution employed
may be, a reference to the molecular weight of the substance and
a simple equation will give the amount of pure alkali or acid in
the substance under examination.
When, in estimating alkaline carbonates, the amount of car-
bonic acid, namely, the percentage of real carbonate, has to be
determined, the following method is simple and accurate: Two
small light flasks with twice- perforated rubber corks, are con-
* After ignition.
89 HANIIAL OF CUENICAL ASALXSIS.
nected wiih a twice- bent tube b (Tig, 55) : the flask K' is provim
with tlie tube d, reac-liing to the bollom of the Qaek, and dosed at
its noier end with a globule of soft wax, or b)' mesns of a email
piece of rubber tubing, the outer end of whieb is closed with a
small piete of lightly fitting glass rod c; that of JT is provided
with the short Hibe a. Two grams of the carbonate nnder exami-
nation are weighed, and introduced into the flask K', together
with a little water; the flask K is half filled with concentrated
sulphuric acid ; the apparatus is then tightly fitted, and weighed.
A small quantity of air is now
P'«. 55- by suction drawn out of flask K
by means of the tube a, whereby
the air in K' is likewise rarefied,
Oa allowing the air to return, a
quantity of sulphuric acid as-
cends in the lube !', and flows
over into flask A"', causing a dis-
engagement of carbonic acid gas,
which escapes through the tuba
<T, after having been dried hv
passing through the acid in A.
This operation is repeated until
the whole of the carbonate is
decomposed, and the process is
i.-riiiiuai'-ii l/v "jicning the wax stopper, or removing the rubber
tulnng, and d"rawing some air through the apparatus by means of
a piece of rubber tubing attached to tube a, and suction, or by
connecting the latter with an aspirator. Should the amount of
heat liberated by the admixture of the suljihunc acid with the
water be considered insuffident for the complete decomposition
of the carbonate, the flask K' may he gently heated, and, after
cooling, nir again drawn through the apparatus. The apparatus
is then re-weighed, and the difference between the first and final
weighings will express the amount of carbonic acid in the 2 grams
of carbonate under examination.
ESTIMATION OF ACIDS (ACI DIHETR Y).
The volumetric estimation of acids is the reverse operation of
the estimation of alkalies, and the methods involved are founded
unon precisely the same principle as has been explained under
alkalimetry. Nothing more is therefore needed than a normal or
Ktandard test-solution of potassium or sodium hydrate, of such a
strength thai one cubic centimeter exactly neutralizes one cubic
centimeter of a normal solution of oxalic or sulphuric acid, A
solution of potassium hydrate having less tendency to attack the
glawi vessels in which it is contained than a similar solution of
sodium hydrate, it is preferred for the preparation of the normal
alkali solution. The preparation of such a solution for use with
VOLUMBTRIO ANALYSIS. 87
sulphuric acid, and the method of determining its exact strength
has been explained on page 81 ; the preparation of a normal alkali
solution, corresponding in strength to that of the normal oxalic
acid, is accomplished as follows :
Standard Solution of Potassium Hydrate,
KOH ; 56. 56 Grams in 1 Liter.
A convenient amount (20 or 30 cubic centimeters) of the normal
oxalic acid solution is allowed to flow from a burette into a beaker,
a few drops of litmus solution added, and, from another burette,
containing a moderately strong solution of potassium hydrate, a
suflBcient amount is added to the oxalic acid solution, stirring
gently with a glass rod until exact neutralization is effected, or
until the last drop of the alkaline solution added, produces a
distinct blue coloration of the liquid. The number of cubic cen-
timeters of alkali solution required, which should be less than the
number of cubic centimeters of acid taken, is then noted, and,
from two determinations with concordant results, a simple calcu-
lation will show to what extent the alkali solution must be diluted
in order that equal volumes of the two liquids shall exactly neu-
tralize each other; thus, if 20 cubic centimeters of the normal
acid solution have required but 18 cubic centimeters of the alkali
solution for exact neutralization, it then follows that to everv 18
cubic centimeters of the alkali solution 2 cubic centimeters of water
must be added, or, 900 cubic centimeters of the alkali solution
diluted with water to the measure of a liter, for the attainment of
volumetric equivalence. Simple proportion will show to what
extent any other quantity is to be diluted.
One hundred cubic centimeters of this normal test-solution of
potassium hydrate contain one-tenth of the molecular weight
(ess 5.6) of potassium hydrate, expressed in grams, and w^ill neu-
tralize an equivalent quantity of an acid.
This test-solution is employed for the estimation of the following
medicinal acids:
One hundred cubic centimeters of the solution will neutralize,
if of officinal strength :
16.66 grams of Acidum Aceticum, U. S. P., spec. prav. 1 048.
100.00 •* Acidum Aceticum Dilutum, U. S. P., spec. pniv. 1.0083.
6.00 '* Acidum Aceticum Glaciale, spec. grav. 1 058.
7.00 " Acidum Citricum.
81.00 , " Acidum Hydrobromicum Dilutum, U. S. P., spec. grav. 1.077.
11.41 ** Acidum Hydrocliloricum, U.S. P., spec. grav. 1.16.
86.40 " Acidum Hydrocliloricum Dilutum, U. S. P., spec. grav. 1.049.
12.00 *' Acidum Lncticum, U. S. P., spec. grav. 1.212.
9.08 ** Acidum Nitricum, U. 8. P., spec. grav. 1.42.
63.45 '* Acidum Nitricum Dilutum, U. S. P., spec. grav. 1.059.
6.30 ** Acidum Oxalicum.
4.r0 '* Acidum Sulphuricum, U.S. P., spec. grav. 1.84.
27.22 ** Acidum Sulphuricum Aromaticnin, U. S. P., spec. grav. 0.955.
49.00 " Acidum Sulphuricum Dilutum, U.S. P., spec grav. 1.067.
7.50 *' Acidum Tartaricum.
88 MANUAL OP CHEMICAL ANALYSIS.
Tlie concentrated liquid acids are to be diluted with four or five
times their volume of water, and the solid ones to be dissolved in
about eight limeB their weight of water before being tesled. To
determine tlie point of neutralization, and the consequent comple-
tion of the process, litmus solution is employed, and the same
rules observed for the details of the manipulation as have been
previously described on page 83. The number of cubic centime-
ters of the normal nlkaline solution employed, lesa than 100, indi-
cates at once the percentage of impurities, or of deficiency of
strength in the substance estimated.
Instead of employing the quantities of acid given in the above
table, it is sometimes preferable, for the reasons staled on page 65,
to lake any convenient quantity of the substance to be tested, and
then to ascertain its exact weight ; the weighings being conducted
in a glass- stoppered bottle, the weight of which has been pre-
viously determined. For such estimations, where the quantity of
substance taken for aualysis is difi'erent from the amount expressed
in the preceding table, the relation of the normal potassium
hydrate solution to the officinal acids with which it may be em-
ployed, is represeuted as follows :
1 cubic centimeter correspoads to 0,0600 gram Ac«llc Add.
I " ■' " " 0.07OO " Citric Acid, crjsinlliMd,
C,[I,0,+B,0.
1 ■' " " " 0.0908 ■• Hjdrobromlc Acid, HBr.
1 " " ■■ " 0.0804 " Hydt.«;bloric Add, HCL
1 " " " " 0,1976 " Hydriodic Acid. HI.
1 ■' " ■* '• 0.0000 " I,HClic Acid. 0,H,O,.
1 " •• •■ " 0.0030 " Nitric Acid, HNO,.
I " " " " 0.0630 " Oxalic Acid, cryBtallized,
C,H,0.+ BH,0.
1 " ' O.OAm " Stilphurio Acid, H,8(V
1 '■ " '• " 0.0750 " Tftrtoric Add, crysUllized,
C,H,0,-
AHALTSIB B7 OXIDATION AND REDUCTION.
The principles involved in the process of analysis by oxidation
or reduction have been briefly alluded to on page 79 ; the methods
of estimation being based upon the determination of the volume
of the solution of an oxidizing agent of known composition requi-
site for the complete oxidation of the substance under examina-
tion, or, in the process of reduction, a definite amount of the solu-
tion of the reducing agent in slight excess of the amount nclnally
required is firnt added, the excess being afterwards determined by
the addition oftheproperquantity of the oxidizing agent ofknown
and delinite strength.
The number of substances which may be estimated by these
methods is very large, embracing, in addition to many medicinal
chemicals and preparations, a large number of technical products
which receive no direct application in pharmacy, whilst the results
k
J
VOLUMETRIC ASALV8I3. 89
attained are iisuftlly characterized by a remarkable aecuraoy,
combiDcd with rapidity and convenience of determination. Indi-
cators to designate the completion of the process are usually the
peniinnent pink coloration imparted by potassium permanganate
solution, the deep blue color produced by the reaction of ferroua
Baits with polnssiuni ferricyanide, or of free iodine with mucilage
of slarch, all of which are so delicute that a little exjierienoe on the
part of llie operator will insure precision and uniformity of result.
Slandnrd Sohilion of Polass'mm Permanganate.
KjMn.O,; 3U. 3.U Grams in 1 Liter.
This solution is prepared, with reference to the amount of avail-
able oxygen, of a decinormal strength, by dissolving 3.14 grama
of pure crystallized potassium permanganate in distilled Water,
ana diluting to the measure of one liter. The solution should not
be filtered, but separated by decantalion from any residual insolu-
ble matter which may be formed upon standing, and carefully
S reserved for use in a glass-stoppered bottle ; the solution being
ecomposed by contact with organic matter, the use of Mohr's
burette with rubber tubing is not admissible, but the one provided
with a glass stop-cock or the Gay Lussac burette has to be era-
ployed.
To determine the exact strength of the solution, about 0.2 gram
of pure iron wire, free from rust and very
accurately weighed, is dissolved in about 20 Fig. 56.
cubic centimeters of dilute sulphuric acid, in
a flask arranged as represented in Fig. 56.
This is made by inserting a piece of glass
tubing through the tightly fitting cork of the
flask, attaching thereto a piece of rubber
tubing in which a vertical slit is made by
means of a sharp knife, and securely closed
at the upper end with a small piece of glass
rod. This arrangement, while permitting the
escape of the gas or steam generated by heat-
ing, affords the beat protection against the oxi-
dizing influence of the air during the solu-
tion of the iron; the opening in the rubber
tubing, in consequence of diminished inter-
nal pressure, being drawn together when the heat is removed, and
the solution allowed to cool.
When all the iron is dissolved, by the aid of a gentle heat, the
solution is quickly cooled and poured into a beaker, and the flask
several times rinsed with small portions of distilled water, which
are added to tlie solution contained in the beaker, and the liquid
finally diluted to about 100 cubic centimeters,
90 MANUAL OF CIIKMICAL ASALTSrS.
The solution of potassium permanganate contained in the burette
should now be added until the pink coloration of the liquid remains
permanent, or, until at least it does not dirottly disappear, indi-
cating that the entire amount of iron contained in the solution has
been oxidized from the ferrous to the ferric stale. The coloration
is most diatinctlv xeen when the beaker is placed upon a sheet of
white paper, and the reaction may be expressed by the following
equation :
10Fe"SO. + 5KMnO. + SHSO, -. 5Fe/"(S0J, + 2MnS0. +
K,SO, + 8H,0.
The number of cubic centimeters of permanganate solution era-
ployed is now noted, and the amount of iron taken being known,
a simple calculation will determine the amount of metaLlic iron
equivalent to one cubic centimeter of permanganate solution.
Were the permanganate solution exactly decinormal, one cubio
centimeter would correspond to 0.0056 gram of metallic iron, but
being usually a little deficient iu strength, the nnmber obtained,
which should be established by at Icajfl two experiments with
closely agreeing results, is accepted as the factor uf the solution.
When the standan^t permanganate solution has been standing
for any considerable length of time, even when well protected
from dust, in a gluss-stopiicred bottle, a slight decomposition takes
place, and the proper factor has then to be ascertained anew in
the manner above described. It should also be remembered that
in volumetric examinations with permanganate, the solution
should be slightly acidulous, in order to hold the resulting man-
ganous oxide in solution, and prevent preuipitation. In the larger
number of cases dilate sulphuric acid is employed; nitric acid,
however, even wlien very dilnie, if it contains the least trace of
the lower oxides of nitrogen, decomposes the solution, and, when-
ever employed, these must, therefore, be carefully removed by
previous Imiling. Hydrochloric acid, when concentrated or
warm, has a reducing action on the jiermanganate, free chlorine
being liberatcl, and consequently in such operations where the
use of concentrated hydrochloric acid is required, as in the esti-
mation of potassium nitrate, the solution, after being heated suffi-
ciently to expel the last traces of nitric oxide, must be quickly
cooled, and largely diluted with water before the permanganate
solution is added. The factor obtained fur the permanganate
suUition by the solution of metallic iron in dilute sulphuric acid,
usually dill'ers slightly from that obtained by its solution in
hydrochloric acid, and consequently in exact experiments should
be determined for the latter acid when this is required to be used
for acidulation or for efi'ecting solution.
The officinal substances which may be conveniently estimated
by permanganate are the iron salts, chlorine water, chlorinated
lime, manganese diuxide, [wtaasium nitrate, alcoholic solution of
VOLUMETRIC ANALYSIS. 91
ethyl nitrite, and oxalic acid. The ferrous salts require no pre-
vious preparation for their estimation, whereas the ferric salts
must first be reduced to the ferrous state by means of nascent
hydrogen, as evolved by the action of dilute sulphuric acid upon
zinc; as commercial zinc usually contains a small percentage of
iron, this must be separately estimated and considered, if in suf-
ficient»amount to influence the result of the estimation.
Standard Solution of Potassium Bichromate.
Kfirfi, ; 294.8. 14.74 Grams in 1 Liter.
This solution receives a similar application in the processes of
volumetric estimation to that of ^potassium permanganate, and is
sometimes preferred to the latter from the fact of being less sub-
ject to decomposition through the influence of light and air, or in
contact with organic matter; it possesses, however, the disad-
vantage of not permitting the observation of the completion of
the process by the change in the appearance of the solution itself,
and requiring the employment of an external indicator.
The principle of its application depends upon the fact that potas-
sium bichromate, in the presence of an excess of acid, yields four
atoms of oxygen to the hydrogen of the acid, leaving three atoms
available either for direct oxidation or for combination with the
hydrogen of more acid, whilst an equivalent proportion of acidu-
lous radical is liberated. When employed as a volumetric reagent,
however, the bichromate always yields the whole of its oxygen
to the hydrogen of the accompanying acid, with the liberation of
an equivalent quantity of acidulous radical ; four-sevenths of this
radical then immediately combining with the potassium and
chromium of the bichromate, whilst three-sevenths become avail-
able.
As one atom of the liberated acidulous radical will convert two
molecules of ferrous into one of ferric salt, one molecule of potas-
sium bichromate is capable of converting six molecules of ferrous
into three of ferric salt, as shown by the following equations:
K^CrO^CrO, -f 7H,S0, -f 6FeS0, = K^SO, -f Cr,(S0j3 -f 7H,0 +
3Fe,(SO,)3.
K,CrO,.Cr03 -f 14HC1 + 6FeCl, = 2KC1 -f Cr.Cl, + 711,0 +
3Fe,Cl,.
The standard solution of potassium bichromate is prepared by
dissolving 14.74 grams of the pure crystallized salt in water, and
diluting the resulting solution to the measure of one liter. In its
application for the estimation of iron, in ferrous combinations, a
weighed amount of the salt is dissolved in a small quantity of
water, the solution acidulated with dilute sulphuric acid, and
the solution of bichromate subsequently allowed to flow into the
liquid from a burette until, after well stirring, a drop of the
92 MANUAL OF ClIEJirCAL ANAtVSIS.
liquid, removed by a glass rod, and pliiced in contact with a drop
of solution of potassium ferricyanide, on a white plate, ceases to
produce a blue color.
As 100 cubic centimeters of the bichromate solution contain
yJ^fOf the molecular weight of I lie salt in grams, the same amount
will effect the conversion of 5^ of the weight of 6 atoms of iron,
expressed in grams, or an equivalent amount of tlie lower salts of
iron, from the ferrous to the ferric state. Each cubic centimeter
of the test-solution thus corresponds to 0.01474 gram of pure
cryatJilIiiied potassium bichromate, or an equivalent amount of
metallic iron and the following olBcinal salts with which it is
employed, i. e.:
1 cubic centimeter corre^xmds to 0.01877 gnan aT Metallic Iwn, Pe.
1 *■ " " '■ 0.03477 " Ferrous Carbonate, FeCO,.
1 '■ " " " 0.0&337 '■ Ferrous Sulpliale, crysliil-
li7*d. FeSO,+7H/).
1 " " " " O.OS0B7 '■ Ferrous Sulphate, dried.
FeS0,-|-H,O.
The following named articles are oflicially directed to be tested
with this solution, and, if perfectly pure or of officinal strength,
at lea.st 50 cubic centimeters of the test solution should be required
to effect the conversion of the stated weights of substance from
the ferrous to the ferric state.
Ferri Cnrbonaa Saccbaratue 13. IS grame, indicating IS per cent, of Ferrous
Ferri SiilpliH!) 4.1G7 " " 100 percent, of the Mlt.
Fern SulpUas Prwcipitstus 4.107 " " 100 " " "
Standard Solutiott of Iodine and Sodium Hyposulphite {Ihioeulphate),
The fundamental principle upon which the method of estima-
tion with these solutions is based, depends upon the indirect
oxidizing action of iodine in the presence of water with the for-
mation of hydriodic acid, and the liberation of oxygen in an
active state, which then combines with the oxidizable substance,
as, e.g., in the case of arsenious acid ;
A8,0, + 2H.0 + 41 - As,0, + 4HI,
or sometimes, as in the case of hydrogen sulphide, by the direct
abstraction of hydrogen :
H.S -f 21 - 2HI 4- S.
These solutions may be employed for the estimation of bodies
capable of absorbing oxygen and decolorizing the iodine solution,
such as sulphurous acid, sulpliites, hydrogen sulphide, alkaline
hyposulphites, arsenites, etc., as also for bodies which contain
available oxygen, free cMorine, or from which chlorine may be
liberated when treated with concentrated hydrochloric acid, such
VOLUMETRIC ANALYSIS. 93
as the chromates, manganates, and all metallic peroxides. Free
chlorine, however, cannot be estimated by direct titration with
sodium hyposulphite solution as in the case of iodine, for instead
of tetrathionic acid being produced, as with the latter, sulphuric
acid is formed, as may be confirmed by testing with barium chlo-
ride ; the chlorine must, therefore, in such cases be passed into,
or added to, an excess of solution of potassium iodide, by which
means the liberation of an equivalent amount of free iodine is
eflfected, and the latter can then be directly estimated with sodium
hyposulphite solution.
The completion of the reaction or process is in all cases indi-
cated by means of mucilage of starch, which assumes in the pre-
sence of the slightest excess of free iodine a beautiful deep blue
color.
Standard Solution of Iodine,
I ; 126.6. 12.66 Grams in 1 Liter.
This solution is prepared of decinormal strength, and therefore
contains one-tenth of the atomic weight of iodine, expressed in
grams, in one liter.
12.66 grams of pure iodine,* and 18 grams of pure potassium
iodide are placed in a liter flask, about 200 cubic centimeters of
distilled water are then added, and, as soon as the solution of the
iodine is effected, the liquid is diluted to the exact measure of
one liter.
Each cubic centimeter of this solution contains 0.01266 gram
of iodine, and bears a simple relation to the following substances
with which it may be employed, i. e. ;
1 cubic centimeter corresponds to 0.0072 gram of Antimonious Oxide, 8b.^0,.
** 0.0167 " Aniimony Potassium Tartrate,
crystallized, K(Sb0)C4H,O,4-iH,0,
or 0.0162 gram of anhydrous salt.
0.004945 gram of Arsenious Acid (anhydride),
Aa,0.,.
0.0097 '' Potassium Sulphite, crystal-
lized, K.,SO,-f 2H2O.
0.0052 '' Sodium Bisulphite,
1
1
1
1
1
1
1
»t
((
(i
((
((
((
((
4(
(( ((
(I ii
(i (i
i» (i
NaHSO,.
(( ((
0.0248 " Sodium Hyposulphite, crys-
tallized, NajSjOj+SH^O.
0.0126 ** Sodium Sulphite, crystal-
lized, Na,SOj-f 7H.,0.
** '* 0.0032 '* Sulphurous Acid ( anhy-
dride), SOj.
The following named articles are officially directed to be tested
with this solution, and, by the employment of the stated weights
♦ In weighing the iodine, it should be brought into a perfectly dry test-tube,
which is anerward tightly corked, in order to protect the balance from the
corrosive action of the vapors.
94 MANUAL OF CHBMICAL ANALYSIS.
of substance, at least 50 cubic centimeters of the standard test-
solution sliould be required, corresponding to the purity or per-
centage strength below indicated.
Acidiim Arseniosum 0.2546 gram, indicating 97 per cent, of the anhydride.
Acidiim Sulphurosnm 4.571 grams, ** 3.5 *' *' dry gas.
Liquor A cidi Arseniosi 25.464 ** " 0.97 ** " anhydride.
Liquor PotassiiArsenilis 25.464 ** *' 0.97 *' *' "
Potassii Sulphis 0.538 *' *' 90 »* " crystallized
salt.
Sodii Bisulphis 0.288 ** ** 90 ** *» salt.
Sodii Sulphis 0.700 *' ** 90 *' »* crystallized
salt.
Stamlnrd Solution of Sodium ffyjtosulphite (thiostilphate).
Na^SjOj -f ollfi ; 248. 24.8 Grams in 1 Liter.
This solution, being likewise of decinormal strength, is pre-
pared by dissolving 24.8 grams of pure crystallized sodium hypo-
sulphite in water, and diluting the solution to the exact measure
of one liter..
Each cubic centimeter of the solution contains 0.0248 gram of
crystallized sodium hyposulphite, and bears a simple relation to
the following substances which may be estimated therewith, i. e.:
1 cubic centimeter corresponds to 0.00798 gram of Bromine, Br.
1 ** ** ** " 0.00354 " Chlorine, CI.
1 " '' ** ** 0.01266 *' Iodine, L
The following named articles are officially directed to be tested
with this solution, and, by the employment of the stated weights
of substance, at least 50 cubic centimeters of the standard test-
solution .*«hould be required, corresponding to the purity or per-
centage strength below indicated :
Aqua Chlori 44.25 grams, indicating 0.4 per cent, of the dry gas.
Calx Chlorata 0.71 gnim, '* 25 ** " chlorine,
lodum 0.633 ** *» 100 " ** iodine.
Liquor lodi Com posit us 12.66 grams, ** 5 ** ** iodine.
Liquor SodflB Chloratte 8.88 ** " 2 '* ** chlorine.
Tincturalodi 7.71 *' '* 8 ** ** iodine.
The solutions of iodine and sodium hyposulphite, if accurately
prepared from pure materials, will be volumetrically equal, and
this is rendered neces.sary in consequence of their frequent inverse
application in the methods of volumetric estimation. In order to
ascertain this fiict, one burette is filled with the iodine solution
(only the form of burette provided with a glass stop-cock or the
Gay Lussac burette should be used for this solution), and another
one with the solution of sodium hyposulphite; a certain number
of cubic centimeters of the latter solution are then allowed to flow
into a beaker, placed upon a sheet of white paper, a little muci-
lage of starch added, and subsequently the solution of iodine,
stirring constantly with a glass rod, until the last drop produces
VOLUMBTRIC ANALYSES. 95
a permanent blue coloration of the liquid. The reaction which
thus takes place, resulting in the formation of sodium iodide and
tetrathionate, is expressed by the following equation ; the per-
manent blue coloration only appearing in the presence of a slight
excess of free iodine :
2Na,S,0, + 21 « 2NaI + Na,S,0,.
The number of cubic centimeters of each solution employed is
now noted, and should the one solution be found to be slightly
weaker or stronger than the other, the stronger solution must by
calculation be diluted with so much water, that an exactly equal
number of cubic centimeters or volume of the two solutions shall
be required to produce the above-mentioned effect.
As the test-solutions, however, even when carefully prepared,
are seldom of precisely the correct strength, their standard must
be fixed with relation to perfectly pure and dry iodine, and the
proper factor thus determined. This is accomplished by reducing
about one gram of pure iodine to a fine powder, drying it on a
watch-glass over sulphuric acid, and then dividing it into two
nearly equal portions, which should be separately weighed in
small glass tubes, and the weight of which, when empty, has
been previously determined. The vials, with their contents,
are then placed in a small flask, each containing about 10 cubic
centimeters of a ten per cent, solution of potassium iodide,
and, as soon as the iodine has become perfectly dissolved, the
sodium hyposulphite solution added from a burette until complete
decolorization takes place, and a slight excess of the latter solu-
tion has been employed; a little mucilage of starch is now added,
and the solution inversely titrated with the iodine solution until
the blue coloration is produced. The amount of iodine solution,
deducted from the amount of sodium hyposulphite solution em-
ployed, will give the number of cubic centimeters of sodium hypo-
sulphite solution equivalent to the amount of iodine taken, and
from which a simple calculation will show the amount of pure
iodine corresponding to one cubic centimeter of either of the test-
solutions. The factor thus obtained, which will usually be found
somewhat less than that theoretically required, will receive appli-
cation in all subsequent estimations for which the test-solutions
may be employed.
The further details relating to the mode of procedure for the
estimation of individual substances with these volumetric test-
solutions will, in order to avoid repetition and to retain the proper
systematic arrangement of the special chemicals, be more fully
(described in the second part of this volume, in the appropriate
place.
AL OF CHEMICAL ANALYSIS.
VOLITMDTRIC ESTIMATION OF SnOAKS.
The most convenient method for the volumetric estimation of
sugars is by a process of reduction, and is baaed upon the fact that
the copper from ao alkaline solution of cuprio tartrate may be
completely precipitated in the form of rod cuprous oxide by boil-
ing with a solution of grape- or milk-itugar; one molecule of pure
grape-sugar being capable of reducing exactly five molecules of
cupric oxide to the cuprous state, and, from which relation, the
amount of copper reduced from a solution of known strength will
bear a direct and simple proportion to the amount of sugar con-
tained in a definite volume of the solution under examination.
The estimations by this method require but little time, aud are
capable of yielding auffieiently accurate results.
The method of preparation of the test-solution of alkaline
cupric tartrate, or "Fehling's solution," has been described under
the head of reagents, page 32 ; it should have been well preserved
in a glas.s- stoppered bottle, and should give no precipitate on
boiling. In performing the tests, ten cubic centimeters of the
copper solution are measured ofl' by means of a pipette, brought
iuto a glass flask of about 100 uubiu ceutiineters oapaeity, and
diluted with water to about fifty cubic oentimeterR. The solu-
tion is then heated nearly to the boiling-point, and the solution of
sugar, contained in a burette, gradually added, allowing the liquid
to boil for a few minutes after each addition, and the precipitate
thereby formed to subside until, after carefully repeating the
operation, the blue color of the liquid entirely cfisappears. The
point at which exactly the proper amount of sugar solution has
been added is difGoult to observe by the simple loss of color of
the solution, and, in order to determine this more exactly, as soon
as the blue color of the liquid is no longer distinctly visible, a
few drops should be removed by means of a pipette, brought upon
a porcelain plate, and, after acidulating with acetic or hydrochloric
acid, tested with a drop of solution of potassium ferrocyanide,
when, if copper still be present in the solution, a distinct, brown
coloration will occur; this manner of testing should be frequently
repeated towards the close of the operation to insure the perfect
reduction of the copper, care being taken, on the other band, that
an excess of the sugar solution be not added.
Grape-sugar and milk-sugar require no previous preparation
for their estimation when in the form of solution, whereas cane-
sugar requires to be first boiled with a dilute acid, by which
process it is converted, through the assumption of a molecule of
water, into grape-sugar, or dextrose, and fruit-sugar or Iffivulose,
both of which exercise the same reducing action on the alkaline
copper solution.
J
VOLUMETRIC ANALYSIS. 97
C„H„0„ + H,0 - C,H,.0, + aH„0.
\
Cane-sugar. Grnpe-sugar. LoBvulose.
The alkaline copper solution, if properly and accurately pre-
pared, bears the following relation to the different varieties of
sugar, and is capable of being exactly reduced in the proportion
of the amounts nere indicated.
10 cubic centimeters correspond to 0.05 gram of grnpe-sugar.
10 »* '* '* ** 0.007 " milk-sugar.
10 ** '* " '* 0.0475 " cane-sugar.
The number of cubic centimeters of a sugar solution necessary
to eftect the complete reduction of 10 cubic centimeters of the
copper solution will therefore contain, according to the variety,
the amount of pure anhydrous sugar stated above, from which
data the percentage strength of the solution may be readily calcu-
lated.
The estimatio'n of sugar is attended with more accurate results
when in dilute than in concentrated solution; solutions containing
not more than one-half, or one per cent., being best adapted for
the purpose, and, if found by a preliminary estimation to be con-
sidcrably more concentrated, they should be diluted with a defi-
nite quantity of water to the proper extent, and again estimated,
when the result of the second estimation, if found to vary from
that of the first, may be accepted as the more accurate.
The test-solution of alkaline oupric tartrate is subject to slight
changes by keeping; for this reason, or even when freshly pre-
pared, it is preferable in all oases to verify its strength, and to
determine its proper ftictor with relation to the dift'erent varieties
of sugar to be estimated. This determination of the factor for
grape-, milk-, and cane-sugar may be readily accomplished as
follows :
I. Orap€-ftu(/ar, dextrose^ or fjlucose^ CrtHjjO^.HjO. — A few grams
of pure crystallized grape-sugar should be thoroughly dried in a
desiccator, over sulphuric acid, by which means the hygroscopic
moisture is removed, but not the water of hydration, which can-
not be eliminated without the decomposition of the sugar, and is
accordingly to be considered in the calculation. One gram of the
sugar, accurately weighed, is then dissolved in water, and the
solution diluted to the measure of 200 cubic centimeters, forming
a one-half per cent, solution. This solution is then brought into
it burette, and the test performed as explained on page 9(5; the
percentage strength of the solution, and the number of cubic
centimeters required for the reduction of 10 cubic centimeters of
the copper solution being known, the amount of pure, anhydrous
grape-sugar equivalent thereto may be readily calculated
II. Milk'Swjar, or lactose^ C„H,,0,, -f HjO. — A few grams of pure
milk-sugar should be thoroughly dried at the temperature of the
7
98 MANUAL OF CHEMICAL ASALYS13.
■water-bath until of constant weight; the hygposcopio moisture
being perfectly removed at this temperature withoni causing any
decomposition of the sugar. A solution containing exactly one-
half per cent, of the dry augar should now be preparecf, and,
haviog been brought into the burctip, the process of titration and
the method of ualeulation are the same &s has been described for
grape -sugar.
III. Ciine giKjar, or sacrhiirose, C,,H^O,j.— Pure cane-augar, pos-
sessing of itself no reducing action, must first be converted by the
action of an acid into grape- and fruit-sugars, a process which
is commonly designated by the expression inversion. One gram
of the sngar, which has been previously dried at 100° C (212°
P.) Until of constant weight, is dissolved, in a graduated flask, in
about 100 cubic centimeters of water, ten drops of hydrochloric
acid are then added, and the liquid heated on the water-bath for
half an hour. After cooling, the solution is diluted with water to
the measure of 200 cubic centimeters ; the process of lilratiou and
the calculation of the amount of pure cane-sugar, equivalent to
ten cubic centimeters of the copper solution, being afterwards
conducted precisely as described for grape- and milk-sugar. The
factors obtained by these means nmy now be employed for the
estimation of the three varieties of sugar in solutions of unknown
strength, and with aeuuraie results.
For ihe estimation of the amount of milk-sugar contained in
milk, the casein and albumiu should first be removed from the
latter before being brought into the burette, and the operation of
titration then conducted as with a solution of pure sugar. For
the quantitative estimation of the amount of sugar contained in
diabetic urine, it is usually advisable to first dilute the urine with
nine limes its volume of water, forming thus a ten per cent,
mixture; the latter is then brought into a burette, titrated as
previously described, and the "calculation made in accordance with
the corresponding decimal for grape-sugar, as stated on page 97,
or, wilh the employment of the proper factor, as derived from
previous estimations with a solution of pure grape-sugar.
ANALYSIS BT PRECIPITATION.
Standard Solution of Anjenlic Nitrati^.
AgNO,; 169.7. 16.97 Grams in 1 Liter.
The principle of the method of analysis by precipitation baa
been briefly alluded to on page 79, so tfiat but a few explanatory
remarks will be required; the application of this solution for the
estimation of the ofBoinal chemicals and preparations being quite
VOLUMETRIC ANALYSIS. 99
as extended as the solutions which have already received consid-
eration in the processes of analysis by neutralization, or by oxi-
dation and reduction.
The standard test- solution is made of such a strength that it
shall be exactly decinormal. 16.97 grams (one-tenth of the molecu-
lar weight) of pure, dry, crystallized argentic nitrate, are dissolved
in water, and the solution diluted to the exact measure of one liter.
This solution may be employed for the estimation of most of
the officinal chlorides, iodides, bromides, and cyanides, including
hydrochloric, hydriodic, hydrobromic, and hydrocyanic acids, and
bitter-almond water; insoluble chlorides must first be converted
into a soluble form by fusing with sodium hydrate, and dissolving
the fused mass in water, or by boiling with a solution of sodium
hydrate, and acidulating the solutions thus obtained by nitric acid.
A number of other substances may be estimated indirectly bv
means of the standard argentic nitrate solution, and, in fact, all
compounds which are capable of being converted into neutral chlo-
rides by evaporation to dryness with pure hydrochloric acid, and
finally heating to about 120^ C. (248° F.), may be estimated in this
way with accuracy; such are the alkaline hydrates and carbonates,
the alkaline earths and their carbonates, and nitrates and chlorates.
The alkalies and alkaline-earths in combination with organic
acids are first ignited in order to convert them into carbonates,
and then treated with hydrochloric acid, and evaporated as before;
nitrates are converted by evaporation with concentrated hydro-
chloric acid into chlorides, while chlorates are converted into
chlorides by ignition. It is evident that in the above mentioned
indirect estimations the chlorine in a combined state is the only
substance actually determined, but as the laws of chemical com-
bination are well known and constant, the amount of chlorine
present in the compound bears a simple relation to the base with
which it is combined, and from which the amount of base to be
estimated may be calculated.
Each cubic centimeter of the standard argentic nitrate solution,
containing 0.01697 gram of the crystallized salt, bears a simple
relation to the following officinal suVjstances for the estimation of
which it may be employed, /. e,:
cubiccentimetercorresponds to 0 00978 gram of Ammoninm Bromide, NH^Br.
" *» '' *' 0.00584 ** Ammonium Chidride, NH^Cl.
O.Olft.l '* Ammonium Iodide, NHJ.
0.01270 ** Hydriodic Acid, HI.
0.00808 '* Hydrobromic Acid, HBr.
0.00364 *'. Hydrochloric Acid, HCl.
0.0054 '* Hydrocyanic Acid, HCN.
(( ii it i«
(( i* ti it
it it <i it
ti ik «« it
it ti it t<
It t< it
tt <t ti
it tt tt
tt tt
tt
*' 0.01198 ** Potassium Bromide, K Br.
** 0.00744 '* Potassium Chloride, KCl.
»* 0.0130 '* Potassium Cyanide, KCN.
** »» 0.01656 '* Potassium Iodide, KI.
** ** ** 0.01038 ** Sodium Bromide, NaBr.
'' ** '' '' 0.00584 '' Sodium Chloride, NaCl.
*' 0.01028 *' Sodium Iodide, Nal.
t( it tt
100
MANUAL OF CHEMII
The following named articles are officially directed to be tested
with this Biilution, and, by the employment of the stated weights
of substance, at least 50 cubic centimeters of the standard argentic
nitrate solution should be required, corresponding to the purity
or percentage strength below indicated:
Acidiim Hydrocjantcum Dilutum 13.5 grams, iodicsllng 3 per ci
Ammonii Bromldum
FnlflSBil Broniidnm
Pntitssll Cynnidum
Sndll Brcimidum
0.477 gntm,
0.«88 ••
0.782 ■■
07
It. orolisnliiie
•' bromide.
" briimide.
" tlie Mil.
" bromide.
The operation of analysis with the argentic nitrate solution maj-
be performed in the case of chlorides, bromides, and iodides, by
dissolving a convenient and accurately weighed quantity of the
salt in water, or by diluting a weighed quantity of the respective
aciils with a small amount of water in a bottle with closely fitting
glass stopper, and allowing the standard test-solution to gradually
flow into the liquid from a burette (preferably the Gay Lussac
bun-tie, or the form provided with a glass stop-cock) until, after
actively shaking the liquid, and allowing the precipitate to sub-
side, a drop of the test-uolution ceases to produce in the clear
liquid any further precipitation. The number of cubic centimeters
of argentic nitrate solution employed represents an equivalent
amount of the substance under examination, as deduced from the
molecular weight.
In tho estimation of the neutral chlorides, iodides, and bromides,
it is more c<.>nvenient to dissolve the salt in a small amount of
water, in a flask or beaker, and then to add a few drops of n neu-
tral solution of potassium chromato before titrating with the
argentic nitrate solution. By this method, the potassium chro-
mate serving as an indicator, the silver solution is simply added,
with constant stirring, until the permanent red coloration of
argentic chromate is produced, which does not occur until the
entire amount of the chloride, iodide, or bromide present has
been converted into the corresponding silver salt.
In the estimation of hydrocyanic acid, or simple cyanides, a
slight deviation from the above described process la made, in con-
sequence of the fact of argentic cyanide forming with potassium
cyanide an easily soluble ■double salt. The swution of hydro-
cyanic acid, or potassium cyanide, is first made slightly alkaline
by the addition of the requi.site quantity of a solution of potas-
sium or sodium hydrate, a few drops of a saturated solution of
sodium chloride are then added, in order to increase the sensibil-
ity of the reaction, and the solution of argentic nitrate finally
added, with constant stirring, until a permanent cloudiness is pro-
duced in the liquid; this marks the completion of the process,
and indicates the point when the argentic cyanide or chloride
VOLUMETRIC ANALYSIS. 101
begins to be precipitated; the argentic chloride not being pre-
cipitated until after the complete conversion of the cyanide into
the soluble double cyanide of potassium and silver. The reaction
upon which the method of estimation of cyanides is based will
become more clearly understood when expressed by the following
equations; the argentic oxide being produced in the liquid from
the nitrate, through the agency of the alkali:
4KCN4- Ag,0 4- 11,0 => 2 AgK CN)«+ 2KnO
2AgK(CN),+ Ag,04-H,0 = 4AgCN + 2KHO.
It is obvious that by this method the number of cubic cen-
timeters of the standard argentic nitrate solution employed to ])ro-
duce the reaction above described, will indicate exactly one-half
of the equivalent amount of cyanide present in the solution ; the
soluble double salt still containing one-half of the original amount
of undecomposed cyanide. In the calculation of such an analysis,
therefore, the number of cubic centimeters of the silver solution
employed must be doubled before multiplying with the molecu-
lar decimal of hydrocyanic acid or potassium cyanide, or, as has
been done in the table on page 99, the decimal may be doubled,
and directly multiplied by the number of cubic centimeters of
solution used, which result will show in either case the exact
amount of true hydrocyanic acid, or pure cyanide in the substance
under consideration.
The amounts of the individual substances which are most con-
veniently employed for estimation with the argentic nitrate solu-
tion, and the salts with which its employment is most applicable,
will receive further mention in the second part of this volume.
7^18 hook is thepropt.
COOPER MEDICAL COI.L..0 ..
SAN FRANCISCO. QAL.
and tV» not to In? ivmo'-'d f'> .»«, (h^^
L:b,:,.„ /;,. , ;., , , ; „^_ ,^^
' '' t
ALKALOIDS.
THE OKXEBAL CHARACTERS, AND METHOD FOR THE SYSTEMATIC
SEPARATION A>D RECOGNITION OF SOME OF THE PRINCIPAL
ALKAUJIDS AND ALLIED PRINCIPLES.
The alkaloids constitute an important, large, and constant It
increasing group of widely diigtrihuted organic bases, which are
either s^>lid, ana then mostly crystalline, or liquid and Tolatile:
and usnally represent the active principle of the plant from which
they are obtained.
They all contain carbon, hydrogen, and nitrogen as essential
on.-itituents. most of them containing also oxygen, which, how-
ever, is wanting in some of the liquid alkaloids. They generally
j>os^;SH a distinct alkaline character, neutralizing acids witli the
formation of salts, which, as a rule, are capable of crystallization,
but. analoironslv to ammonia, their formation is bv direct com-
bi nation, and not attended with the formation of water.
The liquid alkaloids, with the proper precautions and regu-
lation of temperature, mav be distilled unchansred, whereas those
which are solid at ordinary temperatures, upon heating, usually
fir.«t melt, and then with increase of temperature become decom-
posi;d. They often pr)ssess a powerful physiological or toxic
action, even when administered in exceedingly small amounts, a
fact which renders their separation and recognition of much im-
portance in toxicological chemistry and forensic investigations.
When heated with so<la-lime they all develop ammonia, and, by
treatment with alkaline hydrates or with acids, they are frequently
resolved into otiier bases, eitlier volatile or permanent, often of
a complex nature, and generally accompanied by various other
proflucts of decomposition. By the action of concentrated acids
and other chemical agents, the products of oxidation or decompo-
sition which are formed are often of a characteristic color, and
are frequently employed as a means for their identification.
Tlie alkaloids, with a few exceptions, are very sparingly soluble
in cold water, but dissolve much more readily in alcohol and
amylic ahjohol, as also to a greater or less extent in ether, chloro-
form, carV)on bisulphide, benzol, petroleum benzin, and the vola-
ALKALOIDS. 103
tile and fatty oils. Although no general rule can be established
regarding their solubility, the difference of behavior towards
the simple solvents affords a means of separating many of the
alkaloids from other bodies, and from each other, in a form which
will admit of, or aid in, their subsequent identification.
The salts of the alkaloids are for the most part readily soluble
in water, and those which are sparingly soluble are dissolved by
dilute acids with the forraation of acid salts. The larger number
of the alkaloids, as also of their respective salts, possess the prop-
erty of circular polarization; the deviation of the plane of polariza-
tion being in most instances to the left, although this deviation is
influencea in character as well as in extent by the solvent em-
ployed and the concentration of the solution, thus restricting the
practical application of this property for their estimation to cer-
tain conditions and limits.
With many reagents the alkaloids afford special reactions in
common, depending upon their precipitation from their solutions
in a form which, although preseuting no sharply discriminating
individual characters, very frequently serves to determine the
presence of a body of this class, or for its obtainment in a form
better adapted for its purification, estimation, or further chemical
examination. Thus the alkaline hydrates and carbonates precipi-
tate the alkaloids from the aqueous solution of their salts; the
precipitates, however, in some cases being readily re-dissolved by
an excess of the precipitant. To these may be added the follow-
ing list of the more important and commonly employed reagents,
which, in most cases, produce in aqueous solutions of the alka-
loids, or their salts, precipitates possessing general, definite
characters.
Tannic acid [)roduces white or yellowish tannates of the alka-
loids, many of which are soluble in hydrochloric acid, and in some
instances, as in the case of morphine, are readily re-dissolved by
a slight excess of the precipitant.
In this connection the fact should, however, be borne in mind
that tannic acid also precipitates many non-alkaloidal or neutral
bodies, and particularly the large class of so-called bitter prin-
ciples.
Iodine in potassium iodide solution (Wagner), page 39, produces
yellowish, brown, or reddish-brown precipitates, which are insolu-
ble in water, alcohol, and dilute acids.
Potass io-mercuric iodide (Planta and Delffs), page 40, produces
white or yellowish-white precipitates, in which the alkaloid takes
the place of the potassium of the reagent, and which are either
amorphous or crystalline, insoluble in acids, but soluble in alcohol.
PotassiO'Cadmic iodide^ (Mar me, Dragendorff) produces, in solu-
1 Cadminm iodide is dissolved in a hot, concentrated, aqueous solution of
potassium iodide, and tliis solution is mixed witli as much concentrated solu*
lOi
NUAL OF CHEMICAL ,
tions slightly aci'lulnlcd with sulphuric acid, while, amorphoas
precipitates, whicb, after some time, becotiio yellowish and cr_v»-
lalline, and are readily soluble in alcohol or an excess of the
reagent.
PotaaaiobismrUhIc ioditlp^ (Drngendorff) proiluceB, in aolutions
slightly acidulated with sulphuric acid, orange-red, amorphoua
precipitates.
Pkosphomoli/Mic acid* (De Vrij, Sonnenschein). — Thia reagent,
applied in the form of an acid solution of the sodium salt, pro-
dncea yellow or browniah-j-ellow, amorphous, flocculent precipi-
tates, which are insoluble in alcohol and dilute mineral acids, but
are dissolved by the ooncentrated mineral acids, and by sCTcral of
the organic acids.
Mercuric chloride, pnge 39, produces white, crystalline precipi-
tates, which are soluble in hydrochloric acid.
Plnlinic chloridi'. page 8ft, and auric chloride, page 81, form with
mostof the alkaloids double Baits, analogous in com position to those
of the inorganic alkalies, which are usually of a bright yellow
color, either crystalline, or gradually becoming so upon standing,
or amorphous and flocculent, and generally sparingly soluble in
water, but soluble in warm hydrochloric acid.
Picric acid (Hager) precipitates most of the alkaloids, even from
very dilute solutions, m a yellow, crystalline, or amorphous form ;
the procipitales are insoluble in an excess of the precipitant, or in
dilute sulphuric acid, but are soluble in hydrochloric acid.
In addition to the large class of a'kaloids derived from the vege-
table kingdom, science has been enriched, and at the same lime
the labors of the chemical expert renderetl more arduous, by the
comparatively recent discovery and development of a class of
bodies produced by the putrefaction of animal substances, which
closely resemble some of the vegetable alkaloids in their physical
and chemical properties, and which have been designated as
ptomaines (cadaver poisons).
From the lime of iheir discovery by S^lmi and Ganthier, in
1873, much valuable knowledge has been contributed respecting
their physiological action and chemical behavior, by the labors
li'in nf pnlnMlnu iodide rh will t>e sulflcieiit to retnlli tlici ciutmluin iodide lu
sohllirin wbi-n cold.
■ Prepared Troiii biainulh iodide ns potauio-cndmlc iodide la prepared from
cadmium iodide.
' An aqueous sololion of ammoninin niolylidnte, Hciditlitted wllh nilric acid.
Is added 1o an aqneous tiolatlon of Bodiiitn plioaplmte. acidulated wltli nitric
acid ; llie reeulliai; preclpitatf, aCtcr Blinding fur soinu linio. Is filtered {iff, well
washed witli wnler, and dl»snlvcil in asolutinuorBodlum cnrbonntc. TUe wlu-
tioii Is llion evaporated to dryness, and tite residue gently igniled until ammo-
nia ceases to be jfiven olT, Tbe cooled product Is finally dissolved in water,
and so much nitric ncid added aa may be required to dissolve llio precipitate
wbicb Is first funned.
ALKALOIDS. 105
and observations of a number of investigators, but which is not
yet sufBciently complete to admit of their classification. The
ptomaines appear to exist in several distinct forms, although
Hager has designated the alkaloidal product of the decomposition
of animal matter as septicin, with reference to one special body,
which, in explanation of the difference in physical, chemical, and
physiological properties, he believes to be capable of assuming
different modifications, or of undergoing further decomposition
with the production of other bodies of an alkaloidal nature, accord-
ing to the extent of putrefaction.
The ptomaines are mostly volatile, and in this form appear to
bear some resemblance to coniine, possessing in addition to the
general characters of alkaloids a narcotic odor, as also being pre-
cipitated by chlorine- water, but, unli ke coniine, not becoming turbid
on gently warming; while others present a more permanent charac-
ter, with some analogies to atropine, hyoscyamine, veratrine, etc.
They all possess strongly reducing properties, and when added
to a solution of potassium ferricyanide convert the latter into
ferrocyanide, which, on the addition of ferric chloride, yields a
precipitate of Prussian blue. These bodies, although in some
instances inert, have been found to possess, in the majority of
cases, powerful toxic properties ; their distinction from the vege-
table alkaloids may, therefore, be destined to become an im-
portant factor in the problems of toxicological chemistry and
forensic research.
The isolation and identification of the alkaloids and allied prin-
ciples, and especially those of a toxic character, is a subject of
such importance, and of necessity so extended in its details, that
it is properly confined to the departments of toxicological chem-
istry. With this consideration it is the aim to present here simply
a brief outline of the generally adopted process of separation,
together with the more important and characteristic tests for
their recognition.
Although the physical and chemical properties of the alka-
loids, as has been indicated, present a marked variation among
themselves, yet they are nevertheless capable of being divided
into certain groups with respect to their behavior towards sol-
vents, which, although by no means so sharply defined as in the
case of the inorganic bases, still suffices for their separation in a
form sufficiently pure for their identification, or for further expe-
riment.
For the separation of the alkaloids and allied principles from
other extraneous, organic, coloring, or extractive matters, the
method of Stas, as modified by Otto, will here be briefly de-
scribed. This method, which consists in treating the acid and
alkaline solutions successively with ether, and finally with nmylic
alcohol, recommends itself by its simplicity, and is often adopted
in preference to the more complicated method of Dragendorft*
106
MANUAL OF CUEUtCAL ,
whiuh consists in the siiccessivo treatment of both the acid and
the alkaline solution with benzio, benzol, chloroform, and amylic
aloohol, or to the other variously modified prooeises.
The organic material to be examined, if not already in a fluid
condition, should first be mixed with, or dissolved in, water, and
then tested with litmus-paper, in order to ascertain its possible
acid or alkaline character. If il be perfectly neutral, it should be
slightly acidulated with tartaric acid, or, if acid, it is first to be
neutriilized with sodium hydrate, and then, as in the case of an
originally neutral reaction, slightly acidulated with tartaric acid ;
if, however, it possess an alkaline reaction, in which case the vola-
tile alkaloids coniine and nicotine would be indicated by their
odor, tartaric acid is likewise added until a perceptibly acid reac-
tion ia obtained. If the substance in its acidulated solution, as
above obtained, forms a perfectly clear liquid, it may be treated
at nnce with ether, but in the case of articles of food, the contents
of a stomach, vomited matter, etc.. the direct treatment with ether
is precluded, in consequence of the presence of fatty matter or
other impurities, which would likewise become dissolved, and dis-
guise the characteristic reaction of the subsequently applied testa.
The substance in this case, after the previously described treat-
ment, should first be evaporated upon the water-bath to a semi-
solid consistence, then transferred to a flask, about twice its weight
of strong alcohol added, and digested upon the water-bath for
about half an hour. The clear liquid is ihen poured off, and the
residue digested twice or thrice successively in the same manner
with alcohol. The entire amount of mixed alcoholic liquid ia
then fiUered into a capsule, and evaporated upon the water-bath
to the consistence of a soft extract; this is again treated with
strong alcohol, and the alcoholic solution filtered and evaporated
as before.
This latter residue is now treated with a small amount of cold
water, and the slightly acid solution thus obtained filtered into a
flask or other suitable glass vessel, and successively shaken with
two or three times its volume of pure ether. The ethereal solu-
tions, which have been separated as completely as possible from
the aqueous liquid by means of a glass separating funnel, are
then allowed to evaporate spontaneously.
From the acid solution fire herel-y absorM by ether:
Colchicine.,
Dkjitalin.
PlcnOTOXIN.
Caktharidin.
(Also traces of atropine and veratrine, which, however, if present,
will Im! subsequently extracted much more completely from the
alkaline solution.)
ALKALOrOS. 107
The residue left by the evaporation of the ether from the acid
solution, as previously described, is to be dissolved in a small
amount of hot water, the solution filtered, and further examined
for the above-named substances.
In order to avoid repetition, the description of all the more
important alkaloids, together with the allied neutral principles
and glucosides, will be reserved for the second part of this vol-
ume, where their physical properties and chemical character-
istics will be fully detailed, and to which in searching for the
above-named substances, reference should always be made. For
this reason, but a limited number of the more important indi-
vidual reactions of these bodies will here be stated, when, if such
be found to correspond with any one of the substances mentioned,
and in order to exclude any possibility of error, its identity should
be invariably confirmed by the other known tests.
Colchicine^ if present, will be indicated by the yellow color of
the solution ; it is, moreover, precipitated by tannic acid and
iodine solution, but by potassio-mercuric iodide only after being
previously acidulated with a mineral acid. Chlorine-water pro-
duces a yellow precipitate, soluble in ammonia-water with an
orange-yellow color. Concentrated nitric acid colors its solution
violet, changing to red : if the nitric acid solution be diluted and
made alkaline with sodium hydrate, an orange-red color is pro-
duced,
Dujitalin, not properly an alkaloid but closely related by its
properties, is precipitated by tannin only from a concentrated
solution. When it is dissolved, in a capsule, with concentrated
sulphuric acid, and a trace of bromine water is brought into the
liquid, a violet-red color is produced. If a trace of digitalin,
together with a little j)urified ox-gall, be dissolved in a little
water, in a capsule, a small amount of concentrated sulphuric
acid added, and warmed at from 60 to 80° C. (140 to 176° F.),
the solution gradually assumes a fine red color.
Picrotoxin is not precipitated by tannin, nor by the other alka-
loidal reagents. It may be readily obtained in a crj'stalline form
from its solution in hot water or in alcohol. Its aqueous solution
possesses an intensely bitter taste, and, when made alkaline with
a few drops of sodium hydrate solution, reduces an alkaline solu-
tion of cupric oxide on heating.
Cantharidin does not afford the general reactions of alkaloids,
and may be obtained in a crystalline form from its solution in
ether or hot alcohol. It is very sparingly soluble in water, and,
for want of characteristic chemical tests, may be extracted from
the ethereal residue by fatty oils, and recognized by its vesicating
proj>erties.
108 MANUAL OF CHEMICAL ANALYSIS.
The original acidulated, aqueous liquid, which has been sub-
jected to the above treatment with ether, is subsequently gently
warmed in order to expel the small amount of ether which re-
mains dissolved therein, and solution of sodium hydrate in slight
excess then added until, upon testing with litmus or turmeric-
pajKjr, a distinct alkaline reaction is obtained; the alkah)ids are
thus liberated from their combination, and are precipitated, or, as
in the case of morphine, become re-dissolved by the excess of al-
kali. The alkaline liquid is then agitated twice or thrice succes-
sively with pure ether, allowing an interval of about half an hour
to elapse before the separation of each portion of ether from the
aqueous liquid, and finally the mixed ethereal liquids are allowed
to evaporate spontaneously.
II. From the alkaline solution are hereby absorbed by ether:
(a) Liquid and Volatile. (6) Soud and Permanbkt.
Nicotine. Stryciinixe,
CoNiiNE. Brucixe.
Yeratrine.
Atropine,
aconitine,
Delphinine,
Narcotine,
ThEBAIxVE,
Codeine,
Papaverine,
IIyoscvamine,
PlIYSOSTIGMINE,
Emetine.
(Also, possibly, traces of colchicine and ditjitalin^ which are diffi-
cult to abstract perfectly from the acid solution by means of ether.)
Before proceeding to apply the individual tests for the identifi-
cation of tlie alkaloids, it is f>referable first to test the residue
which may l)e left by the evaporation of the ether, in order ))ri-
marily to establish or confirm the presence or absence of such a
body This may be conveniently accom])lished without loss of
material by placing a very small portion of the residue upon a
watch-glass, together with a few drops of water, and then, by
means of a glass rod, adding a trace of hydrochloric acid, in
order to form a solution of the salt. A few dro|)sof this solution
may then be tested u|>on a glass or porcelain plate, with some of
the general alkaloidal reagents, e. </., potassio- mercuric iodide,
iodine solution, tannic acid, platinic chloride, etc., adding a drop
of the reagent by means of a glass rod, and, for better observing
the formation of such precipitates witli the reagents as are of a
light color, the glass j)late should be placed upon a piece of dark
ALKALOIDS. 109
paper or other suitable object. With the attainment of a negative
result by the use of these reagents no further examination need be
made of the substance in question for an alkaloid, and much time
and labor will, therefore, be saved.
If, however, the above general tests have revealed the presence of
an alkaloid, small portions may then be taken for applying the most
characteristic individual tests, commencing the search by testing
for the more commonly occurring alkaloids of the list, and finally,
in case of an affirmative reaction, confirming the result by the
application of as many of the other well-known tests for the sub-
stance as may seem necessary to establish its identity, or as the
usually limited supply of the substance may admit.
NicotiriCj in case of the obtain ment of a liquid residue by the
evaporation of the ether, will be indicated by its strong narcotic
odor. It is not precipitated by chlorine- water, and its aqueous
solution does not become turbid on warming. When mixed
with hydrochloric acid, and cautiously warmed, a reddish-brown
mixture ensues, which, by further evaporation and cooling, gives
upon the addition of nitric acid a violet color, gradually changing
to orange.
Coniine will be indicated by the strong, peculiar, and unpleasant
odor of the obtained liquid residue. It is precipitated by chlorine-
water, and its aqueous solution becomes turbid on gently warm-
ing. Dry hydrochloric acid gas produces first a purplish-red, and
finally an indigo-blue color.
Strychnme dissolves in concentrated sulphuric acid, forming a
colorless solution, which, upon the addition of a trace of potassium
bichromate, assumes a bluish-violet color, changing to cherry-red,
and rapidly fading. (Curarine produces a reaction somewhat
similar to strychnine, but it is not absorbed by ether, either from
an acid or an alkaline solution, and is further distinguished by
other tests, which will be described under group III.)
Brucine produces with concentrated nitric acid an intense blood-
red color, which soon changes to yellowish-red, and, upon gently
warming, becomes yellow. If to this solution water then be added,
it assumes, upon the addition of stannous chloride or ammonium
sulphide (preferably freshly prepared), a beautiful violet color.
Veratrine dissolves in concentrated sulphuric acid with a yellow
color, which, upon warming, changes to blood-red. It dissolves
in concentrated hydrochloric acid, forming a colorless solution,
which, upon warming, assumes a fine, permanent, dark-red hue.
Atropine^ when heated with concentrated sulphuric acid and
potassium bichromate or ammonium molybdate, develops the odor
of bitter almond oil. When applied to the eye, it powerfully
dilates the pupil.
Aconitine produces with concentrated phosphoric acid, upon
warming, or slowly with concentrated sulphuric acid at ordinary
no .MANUAL OF CHEMICAL ANALYSrS.
temperatures, a. violet color. {Delphinirie produces a aimiu
reaction with phospboric acid, but gives also the digitalin reaction
with sulphuric acid and bromine- water.)
Narcolhve dissolves without color in concentrated sulphuric acid,
but the solution soon becomes yellow, and, uiton the addition of a
trace nfnitric acid, blood-red. Concentrated sulphuric acid, which
contains a trace of sodium molybdate, produces a green color, but
if the solution of molybdate be applied more concentrated, the
green soon changes to a fine cherry-red. A freshly prepared solu-
tion of narcoline in dilute sulphuric acid (1 part of concentrated
acid to 6 parts of water), when evaporated very gradually in a
small porcelain capsule, produces a successive change of colors,
becoming first orange-red, then on the edges bluish-violet, and
finally, at the temperature at which the sulphuric acid begins to
volatilize, intensely reddish-violot. Chlorine-water colors solu-
tions of salts of narcotine greenish-yellow, which, upon the addi-
tion of a very little ammonia- water, changes to a transient cherry-
red color.
Thebaine assumes with concentrated sulphuric acid a fine, deep
blood-red <;o!or, which gradually changes to yellowish-red; with
ammonium molybdate in concentrated auIpEuric acid the same
coloration is produced. Its solution in chlorine- water assumes
upon the addition of ammonia-water an intense reddish-brown
hue.
Codeine assumes with concentrated sulphuric acid which con-
tains a trace of ferric oxide in solution, gradually at ordinary
temperaiurea, or immediately upon warming, a beautiful indigo-
blue color. When dissolved in concentrated sulphuric acid, one
or two drops of a concentrated cane-sugar solution added, and
gently warmed, a fine purplish-red color is produced.
Papaverine dissolves in cold concentrated sulphuric acid with a
slight yellowish color, which, upon warming, changes to violet.
The solution in chlorine- water is colored deep reddish-brown upon
the addition of ammonia-water, after some time becoming almost
blackish -brown. With concentrated sulphuric acid, containing a
little ammonium molyl>date in solution, it assumes a green color,
which, upon warming, rapidly changes to blue, and finally becomes
of a fine cherry-red.
Hyoscyamine, for want of any specially characteristic chemical
reactions, may be best recogni»ed by the physiological property,
which it shares with atropine, of producing dilation of the pupil
when applied to the eye. It is distinguished from atropine in
being precipitated from its solutions by platinic chloride, if not
applied in excess, whereas atropine is precipitated by this reagent
only from relatively very concentrated solutions.
Phyaostiijmitte is characterized by its physiological property
of producing contraction of the pupil when applied to the eye.
Its aqueous solution assumes a reddish color upon the addition of
a
ALKALOIDS. Ill
a small amount of a solution of chlorinated lime, which, upon the
further addition of the latter, becomes discharged.
Emetine is particularly characterized by its strongly emetic
properties, which may be confirmed by experiments upon small
animals, by the subcutaneous injection of its aqueous solution.
Its nitrate is a very sparingly soluble salt. An aqueous solution
of emetine assumes with a few drops of a freshly prepared, satu-
rated solution of chlorinated lime, and the subsequent addition
of one or two drops of hydrochloric or acetic acid, an orange
or lemon-yellow color. Concentrated sulphuric acid dissolves
emetine with the production of a green color, which soon changes
to yellow.
It should be observed that veratrine also possesses violent emetic
properties, but this alkaloid is so characterized by other special
tests that it cannot be mistaken for emetine.
III. Alkaloids remaining dissolved in the alkaline solution:
Morphine,
Narceine,
curarixe.
The alkaline liquid remaining after the extraction by ether for
the obtainment of the alkaloids of group II. should first be gently
warmed in order to expel the small amount of dissolved ether,
then acidulated with hydrochloric acid, and subsequently made
slightly alkaline with ammonia-water. The ammonical liquid is
then treated at least twice successively with warm amy lie alcohol,
separating the latter liquid carefully from the aqueous solution,
and allowing it to evaporate, either spontaneously, or by means of
a gentle heat. The amylic alcohol will have thus abstracted the
entire r mount of morphine, and the larger portion of the narceine
from the solution, whilst the remainder of the narceine and the
entire amount of curarine still remain dissolved in the ammoniacal
liquid. The residue left by the evaporation of the amylic alcohol
should first be tested by the general reagents in order to ascertain
the presence of an alkaloid, when, in case of an affirmative result,
the special tests may be subsequently applied.
Morphine reduces iodine from a solution of iodic acid, which
dissolves in carbon bisulphide or chloroform with a violet color.
A neutral solution of morphine or its salts assumes with a small
amount of a dilute neutral solution of ferric chloride a deep blue
color. When dissolved in concentrated sulphuric acid, the solu-
tion gently warmed, allowed to cool, and then a trace of dilute
nitric acid added, a deep blood-red color is produced.
Narceine assumes upon the addition of iodine-water an intense
blue color. Its solution in concentrated sulphuric acid is of a
grayish-brown color, which, upon warming, changes to blood- red.
A solution of narceine in chlorine- water assumes also upon the
112
SIIAL Oy CHEMICAL ANALYS
addition of ammonia-water a blood-red color. (Narceine may be
readily separated from morphine by ita much greater solubility
in hot water.)
For the separation of tlie remainder of the narceine (in case ita
presence should have been determined by the previous extraction
with atnylic alcohol), aa also of the curarine, the alkaline liquid
should be evaporated in a porcelain capsule upon the water-oath
to dryness, the residue then reduced to powder, transferred to a
flask, and digested for some hours with strong alcohol, with the
aid of a gentle heat and frequent agitation. The liquid is then
saturated with dry carbonic acid gas, in order to convert the free
alkali into carbonate, afterwards brought upon a filter, the inso-
luble residue well washed with strong alcohol, and the alcoholic
liquid finjilly evaporated. If this residue is found to be still too
impure for the application of the tests, it should be treated with
warm water, the aqueous solution filtered, and evaporated upon
the water-bath, this residue again taken up with alcohol by the
aid of a gentle heat, the solution filtered, and evaporated aa before.
In the ak'oholic residue the narceine may be recognized by the
previously -described tests, whilst the cnrarine may be readily
abstracted therefrom by means of cold water, in which it is freely
soluble.
Curarine, as previously stated, page 109, produces with sulphuric
acid and potassium bichromate a reaction somewhat .similar to
strychnine, but the coloration is more of a bluish tint, and much
more permanent. It dissolves in concentrated sulphuric acid with
a pa'.e violet color, which gradually changes to a dirty red, and,
after some hours, assumes a rose-red color. With potassium bichro-
mate it forms a quite sparingly soluble salt, analogous to the
strychnine chromate, difiering, however, from the latter by ita
amorphous character.
It is of particular importance in testing for alkaloids, especiaUy
when contained in complex organic mixtures, to obtain them in
the purest possible state, as slight impurities may, according to
their nature, either altogether conceal, or materially influence the
characteristic reactions upon which the recognition of the sub-
stance depends.
In order to effect the purification of the alkaloids when con-
taminated with adhering coloring matter, etc., as also for the
separation of the individual alkaloids from each other, recoarse
must bo had to the distinctions in their physical and chemical
properties, such as behavior towards the simple solvents, or the
produGlion of sparingly soluble simple salts, etc., from which the
pure alkaloid, if desired, can again be obtained.
It should al.Ho be made a rule in the application of the testa to
employ the smallest possible quantity of substance, as the raaa*
ALKALOTDS.
113
tions from their delicacy are usually quite as well obtained as
with larger quantities, even sliould the amount of material at
disposition be considerable, which, however, in forensic research
is rarely, if ever, the case; and the amount of tlie reagent added
should always be proportionate to the amount of the substance to
be tested. For the observance of such reactions as depend upon
the production or change of color, a
small porcelain plate or capsule will be F'o. 57.
found the most serviceable, applying
the reagent, when required in but small
quantity, by means of a glass rod or
»nall pipette (Fig. 57).
In the preceding briefly described
course for the systematic separation of
the alkaloids, it will be evident that
only the more commonly occurring
bodies of this clas.'i, and such as possess
toxic properties, have been considered,
whilst such as arc non-poisonous in
their character, as, e. ij., caffeine, the
cinchona alkaloids, etc., have been in-
tentionally omitted, as not pro|)erly in-
cluded within the province of forensic
chemistry. Should the presence of such
a body, however, be presumed or sus-
pected in the substance under examina-
tion, a consideration of its deportment towards ether or other sol-
vents, in acid or alkaline solution, will at once indicate the method
to be adopted (or its isolation, after the accomplishment of which,
the proper tests for its identification may be applied.
For the separation of the alkaloids when associated with other
organic or inorganic poisons, such as hydrocyanic acid, phosphorus,
arsenic, metallic salts, etc., which may likewise be the object of
search, special methods of manipulation and precautiona are re-
quired to be observed, in order that none of the substances shall
undergo decomposition, or escape detection in the process of ex-
traction, or that the correctne.ss of the result may be thereby
impaired.
Investigations of this character, therefore, should only be en-
trusted to the experienced expert, pos.sessing special knowledge
of the properties and deportment of the bodies in question, which
from their importance are too extended in their sco[)e to admit of
H more detailed consideration in this place, although the charac-
teristic and most reliable tests for the recognition of the above
mentioned, and the more commonly occurring organic and in-
organic poisons, will receive further attention in their appropriate
places in the second part of this volume, and the methods indi-
cated whereby their isolation may be ell'ected.
PART II.
THE MEDICINAL CHEMICALS
AND
THEIR PREPARATIONS, '
THEIR
PHYSICAL AND CHEMICAL CHARACTERISTICS,
WITH DIRECTION 8 FOR THE
EXAMINATION OF THEIR QUALITY AND PURITY, AND FOR
THEIR QUANTITATIVE ESTIMATION.
THE
MEDICINAL CHEMICALS
AND THEIR PEEPARATIONS.
ACETUM.
Vinegar,
Ger. Essig ; Fr. Vinaigre ; 8p. Vinagre.
Vinegar, as obtained by the acetic fermentation of dilute
alcoholic liquids, presents considerable variation in its physical
characters, such as color, odor, taste, etc., imparting properties
which in most instances are unobjectionable, and are frequently
desired in its employment for domestic purposes, while tney do
not always render it inadmissible for pharmaceutical applications.
It must, however, form a perfectly transparent liquid, possessing
a true acetic odor, free from empyreuma, and should contain no
metallic impurities or acrid vegetable substance, as also no free
inorganic or other foreign acids, with which it is not unfrequently
adulterated for the purpose of increasing its strength.
Vinegar con tains, on an average, from 4.5 to 6 per cent, of true
acetic acid. The British Pharmacopoeia requires a spec. grav. of
1.017 to 1.019, corresponding to 4.6 per cent, of absolute acetic
acid. The Pharmacopoeia Germanica requires that 10 cubic cen-
timeters of vinegar neutralize 10 cubic centimeters of normal
solution of potassium hydrate, corresponding to 6 per cent, of
absolute acetic acid.
Examination :
Free mineral acids are readily detected by adding to 20 cubic
centimeters of the vinegar, about 4 or 5 cubic centimeters of strong
ammonia-water, and evaporating in a shallow glass capsule on the
water-bath. If the vinegar is pure, a slight yellow or brownish
residue will remain, whereas in the presence of free mineral acids,
or with tartaric and citric acids, a crystalline mass is obtained.
As the ammonium salts are readily volatilized on heating, and the
tartrate and citrate become thereby carbonized, the presence of
fixed impurities may at the same time be determined.
118 MANUAL OF CnEDICAL ANALVBI8.
The ])resence of mineral acids may, be also readily delected as
follows: A solution of ferric acetate is diluted wJtli water to such
an extent as to appear siiglilly yellowish, and a small amount of
ainmijiiium or potassium sulphocyanide disHolved therein, when
no red coloration will be produced, even upon the addition of
acetic acid; the smallest trace of free sulphuric, nitric, or liydro-
cliloric acids, however, produces an intense red coloration, which
may be rendered still more evident by shaking the liquid with
ether, when the latter will absorb the red ferric suiphocyanide.
Another method consists in mixing a freshly prepared solution
of pure ferrous sulphate, free from oxide, with a solution of gallic
acid ill cold water, which has been previously well boiled ; to the
colorless liquid thus obtained a little sodium acetate is added, and
subsequently a small portion of the vinegar to be tested. The
violet coloration produced by sodinm acetate is destroyed by the
presence of mere traces of free mineral acid, but is not aftected
by acetic acid.
Utilphiiric and Hydrachhric Acids. — A crude mode of delecting
the presence of sulphuric acid in vinegar consists in the addition
of a little cane-sugar to a small portion of it, and evaporating the
solution, at a gentle heat, in a porcelain uapsule, to the consistence
of a thick syrup; this will become almost black if free sulphuric
acid be present.
Since the water and the materials used for the preparation of
vinegar generally uontain traces of sulphates and cntorides, most
vinegar yields a slight turbidity with barium and argentic nitrates.
An undue proportion of sulphuric or hydrochloric acid may, how-
ever, bo readilj' detected by adding to 20 grams of the vinegar
0.6 cubic centimeter of solution of barium nitrate and 1 cuoic
centimeter of decinormal solution of argentic nitrate, and filter-
ing; the filtrate should afford no turbidity upon the subsequent
addition of either barium or argentic nitrates.
The presence of sulphuric acid may also be detected, or verified,
by adding to a portion of vinegar, contained in a test-tube, a satu-
rated solution of calcium chloride, and subsequently heating to
boiling; if, upon cooling, a cloudiness or a precipitate of calcium
sulphate is produced, the presence of free sulphuric acid will be
verified. Oxalic acid would also yield a white precipitate, but
may be distinguished by afibrding a precipitate with a solution of
calcium sulphate.
The presence of hydrochloric acid, in the free state, will be
detected or verified by submittiug a portion of the vinegar to
distillation (Fig, 58), changing the receiver when about one-lburth
of the liquid has distilled over, and reserving this portion for
examination for aldehyde, and aflerward continuing the distilla-
tion until nearly the entire amount of liquid has passed over; the
second portii>n of the distillate is then acidulated with nitric acid,
and tested with argentic nitrate, when a white, curdy precipitate,
insoluble in nitric acid, liut soluble in ammonia-water, will prove
the presence of Lydrixihloric acid.
Aldrhyiie, if present, will be indicated in the first or reserved
portion of the distillate hy its pecnliflr and unpleanant odor, and
may be recognized by its property of reducing metallic
silver from a solution of tnc nitrate ; by tlie formation Fio. OS,
of a crysialline compound wlien shaken with an alka-
line bisulphite; and by a yellow or brown coloration,
or formation of resinous bodies, when mixed with a
strong solution of a uauslic alkali, and gently heated.
Sulphurous acid and sulphites may be detected by
adding a portion of the vinegar to a few fragments of
zinc and u little dilute sulpliuric acid, contained in a
test-tube, and placing over the orifice of the tube a
amuU cap of white, bibulous paper, moistened with a
drop of solution of plumbic acetate (Fig, 59); if snl-
pburous acid be present, hydrogen sulphide will be
evolved, and cause the production of a black slain
upon the paper.
Nitric acid may be delected by adding a drop of
indigo solution to a small portion of the vinegar, con-
tained in a test-lube, and heating, when decoloration
of the liquid will indicate free nitric acid; if, upon
heating, the original tint of the liquid remains perma-
nent, a few drops of concentrated sulphuric acid should
be added, and the liquid again heated, when decolora-
tion of the liquid after this addition will indicate the
presence of nitrates. The test may also be made by
mixing oarefVilly, iu a test-tube, 2 volumes of the vine-
120 MANUAL OF CHEMICAL ANALYSIS.
gar with 1 volume of concentrated sulphuric acid, and subse-
quently adding 1 volume of a concentrated solution of ferrous
sulphate, so as to form two layers (Fig. 60) ; a brown or violet
Fio. 60.
colored zone at the line of contact of the two liquids will reveal
the presence of nitric acid or nitrates.
Metallic I'mpunfies are detected by saturating the vinegar with
hvdrogen sulphide, and allowing the liquid to stand for a few
hours in a closed vessel : if a white turbidity is pnnluced, it will
indicate zinc or sulphurous acid, the latter giving rise to the dejx>-
sition of sulphur, whereas a brown or black precipitate may indi-
cate tin, lead, or copi»er. Tlie precipitate may be examined for
the latter metals by collecting it on a liher, washing with a little
water, and digesting with ammonium sulphide : sulphide of fin will
l>ecome thereby diss«»lve<.l, and. after liltration. may be precipitated
from its s*jlution ^u the addition of an excess of hydrochloric acid
as yellow stannic sulphide. The jx>rtion of the precipitate insoluble
in ammoLiium sulphide is dissolved in a little nitric acid, and a
few drops of dilute sulphuric acid added, when an ensuing white
precipitate will indicate lead: after the removal of the latter, if
present, by tV.tration. ammonia-water is added, in slight excess,
when a Mie eolorati«-»n of the HquiJ will reveal the presence of
rof'p^.r. 0\\\*:T rijetallic impurities than those here mentioned,
which may acoi-ientally be present, may W sought for or deter-
minei aceor liner to the svstematic metho<l of analysis, as described
on pages .:»! t'» f»l.
Acri*! vr /^Mf'k suhtanc^f mav be recoenizetl bv their odor and
taste, eiti-er in the residue obtained by the direct evajx^ration of
ACIDA. 121
a portion of the vinegar, or by previously neutralizing the latter
with magnesium or sodium carbonate, filtering, and subsequently
evaporating the filtrate, at a gentle heat, to about one-third of its
volume.
Fixed impurities may be detected by evaporating a portion of
the vinegar to dryness, and igniting x\\q residue at a gentle heat ;
sodium salts may then be recognized by their property of impart-
ing a bright yellow color to the non-luminous flame, and cal-
cium salts by dissolving the residue in a little water, acidulated
with acetic acid, and testing with ammonium oxalate, when a
white precipitate will be produced. This examination for fixed
impurities may also serve for the detection of free mineral acids,
which, if present, would render the ignited residue neutral in its
action upon litmus, whilst with pure vinegar it will always be
found to possess an alkaline reaction.
Estimation :
About 10 grams of the vinegar, accurately weighed in a flask
or beaker, are diluted with about 50 cubic centimeters of water,
a few drops of litmus solution added, and a normal solution of
{)Otassium or sodium hydrate, page 87, allowed to flow into the
iquid from a burette, until a slight excess above that required
for the perfect neutralization of the liquid has been employed, and
the liquid assumes a distinct bluish tint; the excess of alkali is
then inversely titrated with normal nitric acid until a permanent
red coloration is produced. From the difference between the
number of cubic centimeters of alkali and acid employed, the
number of cubic centimeters of normal alkali required for the
perfect neutralization of the liquid is given, and from this the
acetic strength of the vinegar may be calculated ; one cubic centi-
meter of normal alkali corresponding to 0.06 gram of absolute
acetic acid.
As vinegar is frequently more or less colored, the transition of
color of the litmus from blue to red is not always clearly percep-
tible, and in this case it is better to omit the litmus entirely,
titrating the excess of alkali first added by means of normal nitric
acid as before, until a drop of the liquid, removed by means of a
glass rod, after repeated testing, no longer produces a brown zone
upon turmeric paper, which thus proves the perfect neutralization
of the free alkali.
Should free sulphuric or hydrochloric acid be present in the
vinegar, these must be separately estimated by precipitating small
portions of the vinegar with barium chloride or argentic nitrate ;
from the amount of barium sulphate or argentic chloride thus ob-
tained, the equivalent amount of free sulphuric or hydrochloric
acid may be determined, and the result of the calculation of the
acetic estimation correspondingly corrected.
OF CHEMtCAL ASALTSIS.
ACIDUM ACBTICTTM.
L.
Ocr. EBsigBOure; Pr, Acide ncelique; Sp. Addo actiico,
C,H,0, = CH,-CO-Oni 130.
Acetic acid, wben free from water, forms at or below 15° C,
(5y° F.) large, cilorlesa, transparent, tabular crystaln of the rhom-
bic system (Glacinl Acetic Acid), which melt at 17" C. (62.6= F.).
to a colorlesp, limpid litjuid, of a pungent otior, and strongly acid
reaction. The acid containing much water does not crystallize
even at 0° C. (32^ F.). The specific gravity of the pure liquid
acid is 1.056 to 1.053, at 15- C. (59° F.); it boils at 118^ C. (2i4.4'^
F.), emitting very pungent and acid, inflammable vapors, which
hum with a blue flame.
Acetic acid is miscible in all proportions with water, alcohol, and
ether, and dissolves albumen, fibrin, camphor, and many resins,
gum-resins, and essential oils ; diluted with water, it forms the
commercial and medicinal acetic acids, wlticli maintain the cha-
racier of acetic acid as long as thu admixture of water docs not
exceed 18 to 19 per cent., beyond which dilution the acid loses
more or less the character of a strong acid, and its solvent prop-
erties for tlie above mentioned substances.
In addition to the glacial acid (Acidum Aceticum Glaciale),
two strengths of acetic acid are officinal: Acidum Aceticum of
the spec. grav. of 1.04^ (1.044 British Pharmac, 1.064 Pbarm.
German.X and Acidum Aceticum Dilntuin of the spec. grav. of
1.00S3 (1.006 British Pharmac, 1.041 Pharmac. German.). The
strong acid of 1.048 spec. grav. contains 36 per cent, of absolute
acetic acid, or 30.6 per cent, of acetic anhydride, and 6 grams of
it require for neutralization 36 cubic centimeters of volumetric
solution of potas.sium or sodium hydrate, or 100 parts are neutral-
ized by 60 parts of crystallized potassium bicarbonate ; the diluted
acid of 1.0083 spec. grav. contains 6 per cent, of absolute acetio
acid, corresponding to 6.10 per cent, of ncetic anhydride, and 24
grams of it require for neutralization 24 cubic centimeters of
volumetric solution of potassium or sodium hydrate, or lOO parts
are neutralized by 10 parts of crystallized potassium bicarbonate.
Acetic acid is recognized in its soluble salts, or in the free state,
after previous neutralization with an alkali, by the production of
a deep-red color on the addition of a few drops of solution of
ferric chloride; this coloration is discharged on strongly acidu-
lating the solution with sulphuric acid, or by boiling, in the latter
case the iron being completely precipitated as a basic salt. The
acid may also be recognized, wben not too dilute, by the odor of
acetic ether, when heated with a mixture of equal parts of
alcohol and concentrated sulphuric acid.
ACIDA. 123
EKSmJn&Uoii :
Gliicial acetic acid may be tested for water by mixing 10 parts
of it with I part of fresh or unaltered lemon oil, when a perfectly
clear solution should be formed. A much better method, how-
ever, for the determination of the presence of small quantities of
water consists iu mixing equal parts of the acid and carbon bisul-
phide in a small dry test-tube, which is inclosed in the hand;
wheu maintained at this temperature for a few moments, a per-
fectly clear mixture should result, whilst the smallest amount of
water will produce a cloudiness iu the liquid. The other tests of
purity are the same as those applied for the examination of the
diluted ncids, as follows:
Empyreumalic suletances will be rendered evident by their
odor, and, when present in but small amount, may be also recog-
nizod by neutralizing a little of the acid with solution of potas-
sium hydrate, and subsequently tingeing the solution
faintly with potassium permanganate; the color should fio. 61.
Dot be sensibly changed by standing five mmutes at the
ordinary temperature.
Organic impurities may lie recognized by an ensuing
dark coloration, when the acid is mixed with an equal
volume' of concentrated sulphuric acid, and subse-
quently heated to boiling,
Sulphuric and hyUrocftloric acids may be detected by
an ensuing white precipitate, when the diluted acid is
tested, in separate portions, with barium nitrate or
ohloride, and with argentic nitrate.
Sulphurous acid is indicated by a greeniMh colora-
tion, when a little of the acid is heated with a few-
drops of solution of potassium bichromate; it may also
be recognized by adding a portion of the acid to a few
fragments of zinc and a little dilute sulphuric acid,
contained in a test-tube, and placing over the orilice
of the tube a, small cap of white, bibulous paper, moist-
ened with a drop of solution of plumbic acetate (Fig.
61); if sulpliunms acid be present, hydrogen sulphide
will he evolved, and cause the production of a black
stain upon the paper.
NUrie acid may be delected by the decoloration of
the liquid, when the acid is tinged slightly blue with
indigo solution, and heated; or by mixing the acid
with an equal volume of concentrated sulphuric acid, and subae-
qiienlly carefully adding to the cooled mixture a concentrated
solution of ferrous sulphate, so as to form two layers (Fig. 62); a
brown or reddish-brown zone at the line of contact of the two
liquids will reveal the presence of nitric acid.
Metallic impuritits are recognized by a turbidity or precipitate
npoD saturating the acid with hydrogen sulphide, or upon subae-
MAN0AL OP CHEMICAL ANALY9f8.
quent supersaturation with ammonia-water. If a brown or black
precipilate ia produced by hydrogen sulphide, it roay indicate
tin, lead, or copper, and may be further examined by collecting
it on a filter, washing with a little water, and digesting witU am-
monium sulphide; Rulphide of (in will become thereby dissolved,
and, after filtration, may be repreoipitated from its solution by
the addition of an excess of hydrochloric acid as yellow stannic
sulphide. The portion of the precipitate insoluble in ammonium
sulphide is dissolved in a. little nitric acid, and a few drops of
dilute RulpHuric acid added, when an ensuing white precipitate
will indicate lead; after the removal of the latter, if present, by
liltration, ammonia-water ia added in slight excess, when a blue
coloration of the liquid will reveal the presence of copper. If the
acid, after saturation with hydrogen sulphide, and filtering, yields
a black precipitate upon subsequent supersaturation with am-
monia-waler, the presence of t'ron is indicated.
Pure acetic acio should leave no residue upon evaporation; a
brownish -colored residue would indicate foreign organic matters,
and, upon subsequent ignition, a [lermanent while residue will
indicate salts of the inorganic bases, sodium, calcium, etc. If tbe
residue, when heated on a platinum wire, imparts a bright-yellow
color to the non-luminous flame, sodium salts will be indicated,
and, when subsequently dissolved in water, the solution acidulated
with a few drops of acetic acid, and tested with ammonium oxa-
late, an ensuing white precipitate will indicate arlcium salts.
Estlmatioti t
III consequence of the existing anomaly between tbe specific
gravity of acetic acid and ita strength, the hydrometer does not
ACIDA. 125
always give a correct indication of the latter ; the specific gravity
being increased to a certain extent upon the dilution of the acid,
in consequence of contraction, as will be seen by reference to the
subjoined table.
Thus an acid containing from 77 to 80 per cent, of absolute
acetic acid has the highest specific gravity, 1.0748 at 15^ C. (59^
F.), above which strength it again decreases similarly as upon
dilution, so that the anhydrous acid and an acid containing 43 per
cent, of absolute acid have the same specific gravity at 15*^ C. (59^
F.), viz., 1.055. It will be seen, however, that a specific gravity
below 1.0552 can only apply to an acid containing less than 43
per cent, of absolute acetic acid.
The strength of acetic acid may be determined by observing
the exact quantity of crystallized potassium bicarbonate required
to saturate a known weight of the acid, and by subsequent equa-
tion, see page 122 ; or by the following process of volumetric
analvsis :
Five grams of the acid, accurately weighed in a flask or beaker,
are diluted with about 10 times its volume of water, a few drops
of litmus solution added, and a normal solution of potassium or
sodium hydrate (page 87) allowed to flow into the liquid from a
burette until, with constant stirring, the liquid assumes a distinct
bluish tint. From the number of cubic centimeters of alkali
solution required for the exact neutralization of the liquid, the
percentage strength of the acid may be readily calculated : 1 cubic
centimeter of normal alkali corresponding to 0.06 gram of absolute
acetic acid.
Instead of the employment of a normal solution of potassium
or sodium hydrate, as above described, very accurate results may
also be obtained by the addition of so much of a measured volume
of baryta-water of known strength to a weighed quantity of acid,
as to be slightly in excess of that required for its exact neutraliza-
tion, and subsequently determining the excess employed by means
of a normal acid ; the point of exact neutralization being deter-
mined by means of turmeric paper, which, by the delicacy of its
reaction with baryta-water, will indicate the slightest excess of
the latter by the production of a brown coloration. From the
amount of baryta-water, of previously ascertained strength, re-
quired to neutralize a definite amount of acid, the percentage
strength of the acid may be readily calculated : 1 part of barium
hydrate, Ba(OH)j, corresponding to 0.7017 part of absolute acetic
acid, C,H,0,.
MANUAL OF Cn
TABtE of the guattlil}/ by VKi'ffht of ahtohite Acetic Acid conlained in TOO
parts hy teeiffhl of agtieoiii Acetic Acid of different ipeeific j/raviliet
( Ondemaju).
TemperHlnre nl Iflo C. (5»o F.).
8p«ll<!
pBrwBI.«f
Bl»clll<i
Pur CBOI. of
[ Sp^ita
P(.r»Hl.of
s,«,t.
P.r«Bl..r
gn.iUj.
M.I1CI »ld.
UnrUj.
iKIle Held
ir'^
■>«llc (•tld.
gr"lt»-
■caUsuld.
i.0007
1.0888
28
1 1.0633
~nr
1.0747
76
1.00&3
1.087.1
37
i.oesii
53
1.074H
77
l.OOST
1,0388
38
1 1,0838
1.0748
78
i.OMa
1.0400
30
, 1,0646
54
1.0T48
79
1.00(17
5
1.0413
30
! 1,0653
5.i
1.0748
80
1.0083
1.0434
31
1 l.OrtflO
an
1.0747
Bl
1.0009
1.0438
32
1.0686
57
1.0746
83
1.0118
1.0447
38
1 1,0873
S8
1.0744
88
1.0127
1.04.1B
34
1 1.067M
59
1.0743
R4
1.0143
10 ; 1.0470
3.-,
1 1.06B.5
00
1,0739
85
1.01.17
11 1 1.0481
36
1.06111
81
1,0788
WI
1.0t7i
13 1.04M
37
1.0fi!17
63
1.073 1
87
i.oier.
13 . 1.0.103
88
, 1.0703
63
1,0726
88
1.0200
14 ;i 1.0513
8H
1.0707
84
1.0720
89
1.0214
15 1: IM^
40
1,0713
6.-!
1,0718
90
1.0928
16 1 ' 1 0588
41
1 1.0717
68
1.0701
91
1.0343
17 il 1.0548
43
; 1.0T21
67
10696
93
1.0258
18 1 1,0.).53
1 1.0735
88
1.0686
03
1.03T0
1ft ! 1.05fl3
: 1,072B
80
1.0674
94
1.0284
20
1.0571
1 }.01HS
70
1.0680
»r,
81
1.0580
1.0787
71
1.0644
98
1.08U
38
1.058!)
■ 1.0740
73
1.0635
97
1.0334
28
1.0.598
48
' 1.0742
73
1.0604
98
1.0887
2i
1.0807
49
1 1.0744
74
i.awo
99
1.0350
25
1.0815
so
1.0746
75
1.0553
100
ACISUM ARSENIOSTJBI.
ACIDUM AR3ENIC0SUM. ARSENICUM ALBUM.
Armiimtit Arid. White Arunie. AneninuH Oxide.
Get. Arsenige Sniire; Fr. Acide ai^feaieux ; Bp. Acido araonioeo.
A8,0,;* 197.8.
A heavy, white solid, occurring either in transparent or semi-
transparent masses, which usually have a striated appearance, or
as a white, crystalline powder. In the crystalline condition it is
dimorphous, presenting either the form of octahedra or tetrahedra
of the regular ayptem (Fig. 63), which are obtained by the con-
densation of its vapor under ordinary circumstances, or by erys-
ACIDA. 127
tallization from its solution in water or hydrochloric acid : or the
form of rhombic prisms, which are occasionally deposited in the
roasting furnaces, and are also obtained when hot saturated solu-
tions of arsenious acid, in solution of potassium hydrate or arsenic
acid, are allowed to evaporate slowly.
When freshly prepared by sublimation it forms heavy, trans-
parent, glassy cakes, with a smooth conchoidal fracture, and has a
spec. grav. of 3.738; this becomes gradually opaque and porcelain-
like by passing into the crystalline state, which change proceeds
from the surface toward the interior; at the same time its specific
gravity is slightly diminished (3.689), and
its solubility in water increased. In con- Fio. 68.
sequence of the simultaneous occurrence
of the amorphous and the crystalline modi-
fications, and the diflerence in their solu-
bility, the statements of the solubility of
arsenious acid in water are slightly at
variance.
The crystalline modification is soluble
in about 9 parts of water at 15^ C.
(59° F.), while the amorphous variety re-
quires 25 ])arts of water for solution; but
saturated solutions witli cold water are
very slowly formed. It is slowly but completely soluble in 15
parts of boiling water, but very sparingly soluble in alcohol ; the
amorphous variety requiring 94 parts, and the crystalline variety
400 parts of absolute alcohol for solution. It is insoluble in ether,
but freely soluble in the alkaline hydrates and in warm diluted
acids, especially in hydrochloric and tartaric acids, from which
latter solutions it is deposited, on cooling, in small transparent octa-
hedral crystals. It is also soluble in warm concentrated glycerin,
from which solution it gradually separates by absorption of water,
or at once upon the addition of water.
The aqueous solution of arsenious acid has a feeble acid reac-
tion on litmus; it yields a white precipitate with lime-water, which
is soluble in ammonium chloride; and, after acidulating with
hydrochloric acid, a yellow precipitate with hydrogen sulphide,
which is soluble in ammonia-water or in ammonium sulphide, but
insoluble in hydrochloric acid. Argentic nitrate and cupric sul-
phate produce only a turbidity in an aqueous solution of arsenious
acid; upon exact neutralization with ammonia- water, however, a
ellow precipitate is formed with the former reagent, and a bril-
iant green one with the latter, both precipitates being soluble in
an excess of ammonia- water or of acid.
Arsenious acid, when heated in an open tube, volatilizes at
about 218° C. (424.4° F.) without fusion, forming a colorless, in-
odorous vapor, which condenses, on cooling, in small, transparent,
and brilliant, octahedral crystals. When heated in contact with
i
128
MANUAL OF CHEMICAL ANALYSIS.
reducing agents, such as a mixture of equal parts of fused sodium
carbonate and potassium cyanide, or with carbon, the acid is re-
duced to metallic arsenic, which, when the reduction is performed
in a glass tube, sublimes and is deposited in the form of a bright
metallic incrustation, emitting at the same time a peculiar and
characteristic odor somewhat similar to garlic.
For the reduction of arsenious acid by means of the previously
mentioned mixture of sodium carbonate and potassium cyanide,
the form of tube shown in Fig. 64 is the most suitable.
Fig. 64.
The arsenious acid is first brought into the bulb of the tube,
and the powdered and perfectly dry mixture of equal parts of
sodium carbonate and potassium cyanide then added in such an
amount that the bulb of the tube shall be filled to not more than
half its capacity. The upper portion of the tube should be made
])erfectly clean by means of a narrow strip of bibulous paper or a
small camers-hair brush, and the bulb at first gently heated, in
order to expel all traces of moisture, which may also be removed
by means of bibulous })aper, after which the contents of the tube
are heated to fusion, when the reduced arsenic will form a bright
metallic mirror in the narrow part of the tube.
This methixl of reduction ir also applicable to the nrseiiiates
and to the yellow arseuious sulphide.
The reduction of arsenious acid by carbon is best effected in a
small iul)e, drawn out at one end to a narrow point, as shnwn in
Fig. 65,
The small particles of arseninus acid are placed in the point of
the tube, and above them a splinter of previously ignited wood-
charcoal, as shown in the figure. The portion of the tube con-
taining the charcoal is first heated to redness, maintaining the
tube in a nearly horizontal position, after which the tnbe is grad-
ually inelined, and finally brought into a nearly vertical position,
so that the point of the tube becotnes also heated. The vapor of
the arseniouB acid in passing over the red-hot carbon is reduced
to the metallic state, and deposited above the carbon in tlie form
of a bright metallic mirror. After cooling, the carbon may be
removed from the tnbe, and the metallic arsenic heated for itself,
when, if the amount be qaito small, it will be oxidized for the
most part in the act of volatilization to areenions oxide, forming
a white sublimate of small, shining, octahedral crystals in the
upper part of the tube, and readily distinguiahable by the aid of
a lens.
A solution of arsenious acid in contact with nascent hydrogen,
aa develoj)ed by the action of dilute sulphuric acid on metallic
zinc or magnesium, gives rise to the formation of hydrogen arse-
nide, which, when ignited, burns with a bluisli-wbite flame, and
emits, when considerable arsenic is present, dense white clouds of
arsenious oxide ; when a piece of cold white porcelain is held in
the flame, shining brown or black spots of metallic arsenic are
deposited (MurnU'a test). For further details relating to the appli-
cation of tnifl test, see pages 33 to 156.
When a solution of arsenious acid is mixed with an excess of
concentrated hydrochloric acid, and a piece of bright copper-foil
or wire immersed in the liquid, and boiled, a dark gray metallic
film, consisting of a compound of copper and arsenic, Ou,A8^ is
deposited upon the copper. If the copper-foil or wire be now
removed from the liquid, well washed with water, carefully dried,
and then strongly heated in a perfectly dry test tube, the arsenic
will become volatilized, and at the same time oxidized to arsenious
aeid, forming a sublimate of small, brilliant, octahedral crystals
in the npjier jmrt of the tube {Relnsck'e test).
When the same test ia made as the preceding, with the employ-
130 MANUAL OF CHBMICAL AITALTSIS.
ment of pure tin-foil, or stannous chloride, instead of copper, the
tin becomes likewise coated with arsenic, and at the same time a
more or less voluminous brown deposit is formed (^Betiendorrs
testV To insure success, concentrated hydrochloric acid, and a
verv small quantity of the arsenical solution must be employed,
as the presence of much water prevents the reaction.
Ezamnatioii of Powdered Wbite Anenio :
When a small portion of the powder is heated in a glass tube,
it should be completely volatilized, and form a colorless subli-
mate, which will prove its freedom from admixture with metallic
arsenic or arsenious sulphide ; and when dissolved in warm con-
centrated sulphuric acid, it should form a perfectly colorless solu-
tion, which will prove the absence of organic substances.
Earthy admixtures are recognized by a non-volatile residue
when a little of the white arsenic is stronglv heated on platinum-
foil, or bv an insoluble residue when heatc>d with a solution of
potassium hydrate or hydrochloric acid. When a residue is ob-
tained bv either of these tests, it is collected on a filter, washed
with a little water, and, after drying, mixed and fused in a por-
celain crucible with four times its weight of a mixture of equal
parts of exsiccated sodium and potassium carbonates; the obtained
fused mass is triturated and boiled with a sufficient quantity of
water, and the filtered solution, after acidulation with nitric acid,
tested with barium nitrate for sulphates (calcium and barium sul-
phates). The residue on the filter is washed ^nth water, and
treated with warm diluted hydrochloric acid, and the filtrate sub-
sequentiV tested with sodium sulphate for barium, and, in another
portion, neutralized with ammonia-water, with ammonium oxalate
for calcium.
Ammonium salts will be recognized by the development of the
odor of ammonia, when a small portion of the arsenious acid is
heated, in a test-tube, with an excess of a strong solution of potas-
sium hydrate, and by the formation of white fumes when a glass
rod. moititened with acetic acid, is subsequently held over the
orifice of the tube.
CJdorid^s may be detected by treating a portion of the arsenious
acid with concentrated nitric acid until complete solution is
effiscted, and red nitrous fumes cease to be evolved, and subse-
quently adding to the acid solution, slightly diluted with water,
a few drops of solution of argentic nitrate, when a white precipi-
tate, s<jiuble in ammonia-water, will prove the presence of chlo-
rides.
Estimatioii :
I. One gram of arsenious acid, As^O,, when dissolved in warm
diluted hydrochloric acid, yields, upon complete precipitation
with hydrogen sulphide, a precipitate of arsenious sulphide, As^„
which, when collected upon a tared filter, washed, and dried,
should weigh 1.24 grams.
AOIDA. 181
II. One gram of arsenious acid, As,Oj, is dissolved, by the aid
of heat, in dihite hydrochloric acid, and potassium chlorate, in
small portions, from time to time added, finally continuing the
heat until all free chlorine is expelled; the arsenious acid is thus
converted into arsenic acid, which, after dilution with water, may
be precipitated by test magnesium mixture, as crystalline, ammo-
nio-magnesium arseniate, NH^MgAsO^ + 6H-0. The precipitate,
after standing for twenty-four hours, is collected upon a tared
filter, which has been previously dried at 105° C. (221° F.),
washed with a mixture of three parts of water and one part of
ammonia-water, and dried first at 100° C. (212° F.), and finally
at 105° C. (221° F.), until of constant weight. Its composition is
then represented by the formula NH^MgAsO^ + JH,0, and 100
parts correspond to 39.47 parts of metallic arsenic, or 52.11 parts
of arsenious acid, AsjO,.
III. The estimation of arsenious acid may also be very accu-
rately and quickly accomplished volu metrically by the following
process : 0.1 gram of the acid is accurately weighed, and dissolved
in 20 cubic centimeters of boiling water, with the addition of
about one gram of pure sodium bicarbonate. To the solution,
when cold, a little mucilage of starAi is added, and a standard
decinormal solution of iodine, page 93, allowed to flow into the
liquid from a burette until, after well stirring, a permanent blue
coloration is pro<luced. The amount of pure iodine equivalent
to the number of cubic centimeters employed may then be calcu-
lated, and therefrom its equivalent in pure arsenic trioxide ; 508
parts of iodine being equivalent to 198 parts of arsenious oxide,
as shown by the equation :
21, + As,0, + 5n,0 = 4HI + 2H3ASO,,
508 198
or as follows :
2Na,HA803 + 21, + 2Na,C03 - 2Na,HAsO, + 4NaI + 2C0g.
508
198
The calculation may also be made with the consideration that
one cubic centimeter of the volumetric solution of iodine, if
exactly decinormal, corresponds to 0.00495 gram of pure arsenious
oxide, ASjOj.
The United States Pharmacopoeia directs that if 0.247 gram of
arsenious acid be dissolved, with 0.5 gram of sodium bicarbonate,
in boiling water, the solution should decolorize not less than 48.5
cubic centimeters of the volumetric solution of iodine (corespond-
ing to at least 97 per cent, of pure arsenious acid).
182
MANUAL OF CIlGUtCAL i
Separation and Deteotitm of Arsenio in Forensio InTesUgatiras.—
Arsenious acid, from the fact of being one of the more commonly
employed and readily obtainable poisons, is sometimes the cause
of acciileiital or intentional poisoning, and therefore becomes not
uiifreqiiently the object of search in forensic investigations. In
consequence of the sparing solubilitj of arsenioua acid in aqueous
liquids, it may frequently, in casea of poisoning, be found adher-
iiig to the coatings of the stomach or intestines, or in the vomited
matters. In all cases, however, it should be carefully searched
for among the folds and in the inflamed portions of the stomach
and intestines, when, if thus found, and after purification by
washing with a small amount of cold water, it may be at once
identified by subjecting it to the several testrf already mentioned.
Should the direct isolation of the arsenious acid in substance prove
uusuccc»«sful, other methods for ascertaining its presence must
be then resorted to. The organic matters, as finely divided as pos-
sible, are brought into a flask or retort provided with a condenser
and well cooled receiver, fused common salt or pure rock salt,
and a quantity of pure sulphuric acid not auflicient to decompose
the entire amount of the salt, are then added, and tlie mixture
subjected to distillation (Fig. 66). In the presence of arsenic, the
I very volatile and poisonous arsenic trichloride, AjsCIj, is formed,
I which, in the presence of water, is decomposed into arsenious and
■ hydrochloric acids: 2AsCl, 4- 3H,0 - As,0, + tiHCl. The dis-
I tillale thus obtained, which contains the arsenic in quite a pure
m state, may be at once precipitated by hydrogen sulphide, or em-
I ployed in part for the application of the previously des«ribed
I tests.
I The above metliod for the separation of the arsenic is only
I A k M
ACID4. 133
applicable, however, when present in the form of nrsonious acid
or its salts; and in order to ascertain the jireseuce of arsenical
compounds in general, which may posaihly be accompanied alao
by other poisonuns metallic compounds, the following method may
be resorled to.
The substance under examination, in the tinest possible state of
division, is first deprived as completely as possible of organic
matter, an operation which is most eftectually and conveniently
accomplished by first placing it in a large porcelain dish, and
diluting it with sufficient water to form a thin paste. Concen-
trated hydrochloric acid, equal in amount to the volume of sub-
stance, and a few grams of potassium chlorate are then added, and
the mixture heated upon llie water-bath ; the additiou of potas-
sium chlorate being from time to time renewed, and the evapo-
rated water or expended acid beingalsorenewed, if necessary, until
finally the mixture assumes the form of a thin, homogeneous, yel-
lowish liquid. A small additional quantity of potassium chlorate
may now bo added, and the mixture again heated until the odor
of chlorine entirely disappears. The solution, which should still
possess a stmng acid reaction, is then filtered iuto a small flask,
and, after heating to about ti0-60° C. (140-176° F.), saturated
with hydrogen sulphide, the flask loosely stop[)ered, and allowed
lo stand in a warm place for about twenty-four hours. If the
odor of the gas should have disappeared after standing, the solu-
tion must be again warmed, and subsequently again saturated with
hydrogen sulpTiide, until complete precipitation is finally etTected.
The precipitate thus obtained is collected on a filter, washed with
water previously saturated with hydrogen sulphide, and, in con-
sideration of the possible presence of the sulphides of other metals
than arsenic, digested, with ammonium sulphide. The solution
tlius obtained is brought upon a filter, and the filtrate, together
with the washings, evaporated in a porcelain capsule, by the aid
of a gentle heat, to dryness. The residue is then treated with
concentrated nitric acid, and the obtained solution evaporated at
a gentle heat until the residue no longer shows a dark coloration,
but in a moist condition appears of a yellowish hue. A small
quantity of pure sotlium hydrate, auflficient to neutralise the free
acid, is then added, the mixture evaporated to dryness, subse-
quently mixed with the proper quantity of a mixture of one part
of fused sodium carbonate and two parts of sodium nitrate, and
brought into a small porcelain crucible, and. with a gradually
increased temperature, heated to fusion. The fused mass, which
will contain the arsenic in the form of soluble sodium arseniate,
is treated with water, the soluble portion filtered ofl', and the re-
sidue washed with water containing a little alcohol, when any
antimony present will remain behind as insoluble sodium antimo-
niate. To the arsenical solution a small quantity of sodium bicar-
bonate is added, or preferably carbonic acid gas is passed into the
134 MANUAL OF CHEMICAL ANALYSIS.
Bolution, in order to separate any traces of tin which may hare
become dissolved, and tlie solution filtered. The aolution la now
strongly acidulated with dilute sulphuric acid, and carefully evap-
orated, at a gentle heat in a porcelain capsule, until vapors of
sulphuric acid begin to appear, in order to effect the removal of
the nitric and nitrous acids. The residue in the capsule, which
will form a colorless, strongly acid liquid, is to be diluted with
water, and is then adapted for the application of the several tests.
If a quantitative estimation of the arsenic is desired, it may be either
Srecipitated from the warm dilution directly, or, after previous re-
uction by means of sulphurous acid, as arsenic trisulphide, and
weighed as such; or precipitated in the form of the crystalline
am moiiio- magnesium arseniate by the addition of test magnesium
mixture. 100 parts of arsenic trisulphide, As^,, when dried at
100« C. (212° F.), correspond to 80.4!) parts of arsenious oxide,
AbjOj, or Bl parts of luelalJic arae.iic; and 100 parts of ammonio-
magnesium arseniate, NH^MgAsO,-f- JH,0, dried at 105° C. {221°
F.), correspond to 62.11 parts of arsenious oxi<le, A.^^,, or 'idA7
parts of metallic arsenic.
DeteotioQ of Arsenlo in Coloring-matterB, Wall-paper, Fabrios,
etc. — The employment of arsenic in the preparation of some of
the aniline colors, and the application of Scheele'a Green (cupric
arsenite) or Schweinfurth Green (cupric arsenite and acetate) in
painting, paper staining, etc., often renders the examination of
various materials and products for arsenic necessary or desirable.
Tlie following method, which is simple and accurate, will admit
of general application:
The material to be examined is finely divided, and, when pos-
sible, the coloring-matter separateii from the material (wood,
pa[>er, cotton, wool, silk, etc.) to which it is attached. It is then
brought into a porcelain cajisule, concentrated hydrochloric acid
and a little potassium chlorate added, and gradually heated upon
the water-bath. The organic substances will thereby become com-
pletely destroyed and dissolved, or, after the complete oxidation
of the coloring- matter, may be mechanically renn)ved from the
capsule. A little potassium chlorate is occasionally added to the
flolution, which is further heated on the water-bath, and finally
evaporated to dryness, to eftect the complete removal of the free
chlorine. The residue is then dissolved in water with the addi-
tion of a little dilute sulphuric acid, and finally examined in
Marsh's apparatus, as described on pages 33 to 36.
Another method consists in digesting the material to be ex-
amined, or the coloring-matter removed therefrom, with hydro-
chloric acid, spec. grav. 1.12, for about one hour, subsequently
warming gently, and finally heating a portion of the liquid thus
obtaineu, in a test-tube, with a concentrated solution of stannous
chloride, or a piece of pure tin-foil ; if arsenic be present a brown
coloration, or a brownish- black precipitate, will be produced. Ag
J
AGIDA. 185
a confirmative test the precipitate may be collected on a small
filter, washed with a little dilute hydrochloric acid, subsequently
dissolved in nitric acid, and the filtered solution evaporated at a
gentle heat, in a porcelain capsule, to dryness. The residue, dis-
solved in a little water, is then adapted for further examination
by the application of Marsh's test.
If the article under examination is susf)ected to contain Sch wein-
furth or Scheele's Green, a small portion may be digested with
ammonia-water, which will thereby assume a deep blue color. A
portion of the ammoniacal solution, after acidulation with dilute
sulphuric acid, may then be tested in Marsh's apparatus for arsenic,
and another portion, acidulated with hydrochloric acid, tested with
potassium ferrocyanide, when a reddish-brown coloration will
reveal the presence of copper.
ACIDUM BENZOICUM.
ACIDUM BENZOICUM 8UBLIMATUM. FLORES BENZOES.
Benzoic Acid. Phenyl-formic Acid. Bemol-carhonic Add,
Gcr. Benzoesaure ; Fr. Acide benzoique ; Sp. Act do benzoico.
C,H.O, - C,H,-CO-OH ; 122.
Colorless, soft, feathery needles, or laminae, of a silky lustre,
inodorous when cold and pure, but developing a faint odor when
gently warmed. The agreeable aromatic odor of the officinal
benzoic acid is due to traces of essential oil. When derived from
solutions, benzoic acid forms colorless, pearly needles or laminae
of six-sided prisms. When warmed, the acid begins to volatilize
below 100^ C. (212° F.), and melts at 121 C. (249.8^ F.), forming
a colorless liquid, which, on cooling, solidifies to a mass of radi-
ating crvstals; at 145° C. (293° F.) it volatilizes freely, and at
249-250° C. (^480.2-482° F.) boils, without decomposition, emitting
acrid and irritating, inflamable vapors. When heated with wat^r,
it is also volatilized to a certain extent with the aqueous vapor;
and when heated with an excess of freshly slaked lime, benzol is
evolved.
Benzoic acid is soluble in 500 parts of water at 15° C. (59° F.),
and in 16 parts of boiling water, the solutions possessing an acid
reaction ; it is also soluble in 3 parts of cold, and 1 part of boiling,
alcohol, in 3 parts of ether, 7 parts of chloroform, and freely solu-
ble in carbon bisulphide, warm petroleum benzin, glycerin, and
many volatile and fatty oils, as also in solutions of the alkaline
hydrates. Concentrated sulphuric acid dissolves benzoic acid
readily, without decomposition, and without coloration, if pure,
the officinal acid producing a slight brownish coloration ; on the
addition of water it is precipitated unchanged. A concentrated
aqaeous solution of benzoic acid, when carefully neutralized by
AL OF CUEMICAL ANALYSIS.
ammonia-water, prtxluces, on the addition of a solution of ferric
chloride or aulpliate, a reddiab -yellow or flesb-colored precipi-
tate 'jf basic ferric benzoat-e, which dissolves on the addition of a
small quautitv of warm hydrochloric acid, and, upon cooling,
benzoic acid is again separated, re-dissolving on tbe addition of
alcohol or ether.
Pure benzoic acid does not melt under water, but certain im-
purities, even when present in but small amount, impart to it this
property, at the same time rendering it more freely soluble in
water, and causing tbe formation of smaller crystals. These obser-
vations formerly led to the incorrect acceptance of tlie existence
of different modifications of the acid, as derived from different
sources; a supposition which is not in harmony with the present
views of the constitution of benzol derivatives, according to
whicli, but one mono-substitution product of benzol is capable of
.existence, wiiilst the error of the conclusion may be also demon-
strated by the purification of such an acid, either by distillation
with aqueous vapor, treatment with potassium permanganate, or
other means, when a product possessing all the physical and
chemical properties of the pure acid will be obtained.
Examination :
Hippuric acid, as is well known, is resolved by the action of
hydrochloric acid, and other agents, into benzoic acid and glyco-
coll, and much benzoic acid is obtained from this source.
CH,— CO-OH
I -I- H,0 - CH,{NH,)CO^OH + C,H,-CO-OH
NH— CO-C,H,
Hippuric acid. Olycocoll. Benzoic add.
Such acid, although chemically identical with the acid obtained
from benzoin or other sources, is usually accompanied by an un-
pleasant, persistent odor, which renders it objectionable for phar-
maceutical or medicinal purposes unless further purified, or the
characteristic and agreeable odor of the oflicinai acid subsequently
imparted to it by mixing with a portion of benaoin, and subjecting
it to sublimation.
Hippuric acid may be distinguished from, or recognized in, ben-
zoic acid, by heating, in a test-tube, a small uortion of the acid
with about twice its weight of dry potassium hydrate, and a little
water ; if hippuric acid is prenent, it will be indicated by the odor
of ammonia, as also by the formation of white vapors, when a
glass rod, moistened with acetic acid, is held over the orifice of the
tube. It may also be recognized by forming a very dark colored
or black solution when warmed with concentrated sulphuric acid ;
and when heated for itself in a glass tube an odor resembling that
of" bitter almond oil is produced, accompanied by the final pro-
duction of a black, carbonaceous, or resinous Hke residue,
Chloro-liejizoic acid may be recognized bv mixing a small por-
tion of the acid with a little recently ignited anil moistened cuprio
ACIDA. 187
oxide, and introdacing the mixture, contained on the looped
end of a platinum-wire, in the non-luminous flame; a green or
bluish-green color imparted to the flame would indicate a cou-
taminntion with chlorinated compounds.
Cinnnmic acid may be detected by the development of the odor
of bitter-almond oil, when a small portion of trie acid is genllv
heated in a teat-mbe, with an equal quantity of potaHsium bi-
chromate and sulphuric acid, and allowed to cool ; or when gently
heated with about an equal quantity of potassium permanganate
and a little water.
Salicylic acid may be detected by the production of a violet
coloration upon the addition of a drop of a solution of ferric chlo-
ride to the aqueous solution of the acid. '
Boric acid may be recognized by the green coloration of the
flame of burning alcohol, previously saturated with the acid.
Oxalic acid may be readily detected by its much greater solu-
bility in cold water, and, when subsequently neutralized by
ammonia-water, a white precipitate of calcmm oxalate will be pro-
duced on the addition of a solution of calcium sulphate.
Jtfi'nfrn/ substances, not readily volatilizable or soluble in alco-
hol, may at once be detected by a residue left on volatilization, as
well aa upon solution of the acid in alcohol. If any fixed residue
is left, it may be dissolved in warm water acidulated with nitric
acid, and tested with barium nitrate for sulphates, and with ar-
gentic nitrate for chlorides, and, after neutralization with ammonia-
water, with the latter reagent for phosphates.
ACIDUM BORICUM.
Sorie Add. Orlho-hork Acid. Bonieir, Acid.
Ger. Bursaure ; Fr. Acidu Uorscique ; Sp. Acido b6iica.
H,BO,-.B(OH),; 62.
Colorless, translucent, shining, six-sided lamina) {Fig. 07) belong-
ing to the tri-clinic system, permanent in the air, and somewhat
unctuous to the toucn. Its specific gravity
ia 1.4347 at 15° C. (59* F.).
Boric acid is soluble in 25 parts of cold,
and in 3 parts of boiling, water. The solu-
tion has but little taste; it feebly afi'ects blue
litmus- pa per, but imparts to turmeric-paper
a reddish-brown tint, which becomes more
distinct after drying.*
The acid is also soluble in 15 parts of cold,
nnd in 5 parts of boiling, .ilcohol, and the
* A Rimiliir cnlortitloii ia prnduced by itlknilpa w<1b turmeric paper, biit tlie
cnlnr diwtppeikra nn ilii; aiMltion of liydrocliloric ftcld, wliilat tliiil produced hj
boric ncld reuinins uuullerGd.
Fio, 07.
^
138 MASUAL OF CHIMICAL A5ALT8I8.
solution bums« when ignited, with a flame tinged with green. The
same green tint may be observed when the acid is diasolved in
warm conoentrated gljoerin. the latter heated to boiling, and the
vapors then ignited, or when a small portion of the acid, con-
tained on the loof^ end of a platinum-wire, is brought into the
fusion zone of a non-luminous flame. The salts of copper and
thallium, as also s«3me organic compounds, impart a green colora-
tion to the flame, but these are usually readily di^tingaiahed bj
other physical or chemical characters.
When* boric acid is heated to 1<X»- C. (212° F.i. it parts with 1
molecule of water of constitution inot crvsiallizationi. and is con-
vene«i into mita-U*nc actiL BdOIT^: if heated for some time at
14<>® C. 1 254- F.«. /'yrf-?-r,n> ac-'L Bp,(OH), is formed, which may
be considered as produced from 4 molecules of the ordinary
or onh«>boric acid, bv the abstraction of 5 molecules of water,
4B0H>,— 5H,0— BP/OHV This acid, which is dibasic forms
verv stable salts, of which the ordinarv borax mav be taken as a
represeiiiaiive. If bc»ric acid be heated to redness, a further de-
comr-"«s:::on takes place, by which from 2 molecules of the acid 3
molecules of water are abstracted (corresronding to a loss of 43,d5
per cest. in weight i. and loron tnoxiJf^ ^fir ^*^ obtained.
23*0^3— 3H,0-B,0,.
This forms a glassy, transr*arent, and xery hygroscopic solid,
wnic'r: readily unites with water to lorm boric acid. It {K^sesses
:he ; r-.'iieny of 'iissolving most metallic ox:des at a red he^t,
mhi'iL frtiquer.tly impan characterisiie cV.ors to the mass, and
this reader ::. or the more eommoiilv eraploved borax, a valuable
ape"-: in b'.ow-iiie analvsis.
A STT-all i-rrtion of the crystals of lx»no acid is added to five
linjes .:s weight of water in a test-tube, and heated : a clear and
•v-ri: Irte 5->l itior. niust take place, aiHi, when par: of the hot solu-
t:-.*r. :s i'.':r-ri into alc^'hol. no lurb.Jity or precipitate must
er^ur: vtherwise the i^resenoe of admixtures insoluble or less
so.zb.^ in 'i*'a:e'" or aloh^x is indicated.
I: riiili •::s?..lve in warm c«?ncoRtrate\l sulphuric acid without
dii-rr.zirrrr.rr.: of i^a.- bubbles, and without coloration, and, when
C'lL :h-r =->*.n::o7. -hould aiTori no oolonition iT:«on the addition of
a *<i:^ri:« s-l;::: -n of ferrous sulphate, which would prove the
3i}.fi^Z'X •:■: nitrates.
J/f'j. T '— 1/ *!'-'• V* n:ay be reC'^ir:ize.i in the aq'ieous solution
of the i::i ' v m rn*uinc dark C'-'oration or a i^recit>itate when
?it::rit^i -arit:. ..v^r -j' n sulrhiae. or u;n.^n the sulvseouent addition
• . . ■ -- * • *
' ' > • . ::'./ A>i WT, S-jitf. — The former may be detected in the
L'^--^ -- ?-:'. ::. z. :■: the 3i--i-I bv an en^-iinir white i^recipitate when
teste: -•::n ^zT.:r.'yz.:zzn oxalate, and the latter by heating a frag-
ACIDA. 139
ment of the acid, contained on the looped end of a platinum- wire,
in the non-luminou8 flame; a persistent yellow color imparted to
the flame would indicate the presence of sodium salts or borax.
Chlorides and sulphates are detected in the aqueous solution,
acidulated with nitric acid, by white precipitates, when tested with
argentic nitrate and barium nitrate respectively.
Estimation:
The estimation of free boric acid may be accomplished by
adding an accurately weighed quantity of pure, fused sodium
carbonate Tabout 2 parts of carbonate to 1 part of acid), evapo-
rating to aryness, after the addition of the carbonate, if the acid
should be in the form of solution, finally heating the residue to
the point of fusion, and, when cold, determining its weight. The
amount of carbonic acid contained in the fused mass is now deter-
mined, as described on page 86, and, from the difference in the
amount of carbonic acid contained in the weighed quantity of
carbonate taken, and that determined after fusion with the acid,
the amount of carbonic acid expelled by the boric acid is ascer-
tained, from which the equivalent amount of boric acid may
readily be calculated.
ACIDUM CARBOLICUM.
CarMie Acid^ or Phenic Acid, Phenol, Plunylie Alcohol, HydroxyUhenMol.
Ger. Carbolsaure ; Fr. Acide carbolique ; Sp. Acido carb61ico.
C,H,0=C,H,-OH; 94.
Long, colorless, prismatic needles, or crystalline masses, possess-
ing a peculiar distinctive odor, and a sharp, burning taste, and
having the specific gravity of 1.065 at 18^ C. (64.4° F.). When
perfectly pure, as obtained by re-crystallization from warm petro-
leum benzin or other solvents, it undergoes no change, melts at
44° C. (111.2° F.) to an oily, colorless liquid, and boils at 187° C.
(868.6° F.); but, when slightly impure, or through the influence
of certain agencies, as, for instance, ammonia-gas, it assumes a
more or less pinkish tint, absorbs moisture on exposure to the air,
and gradually deliquesces. The commercial acid usually contains
a small quantity of cresol, and probably aLso other homologous
phenols, which, however, do not materially modify its essential
properties or value ; but the melting-point and factor of solubility
of the pure acid in water become thereby slightly decreased.
Carbolic acid is soluble in 20 parts of water at 15° C. (59^ F.) ;
with about one-tenth of its weight of water it forms a crystalliza-
ble hydrate (C,H5~0H),-f H^O, which remains liquid at tempera-
tures above 16° C. (60.8° F.), and which is rendered turbid by the
further addition of water until 20 parts have been added, when a
l^)
ma57ai •:? raiUMAi .*5.^ltt:*.
• •■■i". •'i-* ■ -"• ■" •■■*■ ■•■l"'i'i ".-" I't- "'".■»-••'■ lt*t-**"i' li*"i*
• -<. '• . .'.. ... . .... .•(. .*.'. .!.• ...'.~a *, . .tl..._. l*.1.-4<. >X«- ^ -«•
I'.T ii. :■;• ■:.? '■ . :"■• . .: :> ":•. i'.-":-." ; '.u "-sr-jji: er. i:i a^rulates
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L
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Z »..' .-.;-■...: ». *• i I .*. :i«. . ■ . - ..-; . _rr'ri-.'.>?
- •-.- k.' . . ' • ; .- . \ .. « 1 :■ ■ ■ ^ . .i-: i\.' .-.i^ ',i. :in
.. .•.'... k. . . I"'.. .1. ' '. I*.'. ■•..' .iT _M . Ai lAib
•
■■■*"'' ■ ■■ ' . . _". . N
r ." -'-:.■ ■■■•''.: I *: -. :"• ' ■■■ ' "t .■ it;:-' -::.ir *^e
* ■*■"*'•■■■■•' m^ < ■ '*■ ■ I ■ ^ I ' r* i
i^ ■ • '.- **--..^
. . • -i- ■■■:■-. ■: !.;.-:. • • M ":■:!.
■■■ " 1 : :•' i:' •- vj- • : i^i t;-^ : ;.■■. -:. :s r '\J.' '.z.
V . - :■: •• ■ ■• ;• •■ ■•:•■•:•■ ■. . I '"'z - .■ ;■ :"i':--r. :s
■ ■ >• B.t-a*.* 1 V, ..14-. .1. ft hA ^ - »
« I
■I I •
— IB - • ■>«,.■
1 ■ ^ ^t ■ 1
: . :. V
I. ■ ■ ,. f"o - ^
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: '1 I'.'"l"l".l^.
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■t , ■■
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Ezannnatiaii
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. .- L.
\ . .-•
ACID A. 141
OnoMole and cregylic acid, or cresol. may be likewise detected by
nddiDg to the liquefied acid, coiil-ainiiig 5 per ueut. of water, an
equal volume of glycerin ; a perfectly clear mixture should be
formed, which should not bo rendered turbid by the subsequent
ndditiou of 3 volumes of water, otherwise an undue amount of
the ftbove-mentioDed impurities will bo indicated.
XBtimation ;
The estimation of pure carbolic acid in an impure product may
be accomplished by dissolving a few grams of it in a porcelain
capsule, by the aid of heat, in a solution of potassium or sodium
hydrate, evaporating the solution to dryness, heating to a tem-
perature not exceeding 170° C. (338° F.), and dissolving the
residue in about ten times its weight of water. To the filtered
solution, su'ffiDient dilute hydrochloric or sulphuric acid ia added
to libenite the combined carbolic acid, wliicli may llien be sepa-
rated by means of a pipette, washed with a saturated solution of
common salt, and finally deprived of water by means of fragments
of calcium chloride, after which it may be introduced into a dry
gla.ss vessel, and weighed ; or, after purification, the aqueous
solution of the carbolic acid may be precipitated by bromine-
water, in the form of the sparingly soluole tribrom-phenol,
C(U,Br,.On, the precipitate then collected upon a filter, washed
with a very small amount of water, and dried at a temperature
not exceeding 90° C. (194" F.). One hundred parts of this com-
pound correspond to 28.40 parts of pure carbolic acid.
The estimation of carbolic acid may also be eflected with con-
Biderable accuracy volumetrically, by a process which likewise
depends upon the formation of the sparingly soluble
tribrom-p ho no!. Bromine-water (the strength of
which has been previously determined separately by
adding an excess of potassium iodide to a measured
portion, and estimating the liberated iodine by means
iif a standard solution of sodium hyposulphite, page
94) is added, in slight excess, to a known amount
of an aqueous solution of the carbolic actd ; the
number of cubic centimeters of bromine-water re-
auired are then noted, and, after the separation of
ttia tribrom-phenol by filtration, an excess of potas-
siain iodide is addeij to the filtrate, and the liber-
ated iodine, which bears a direct proportion to the
cxcesis of bromine employed, estimated with standard
solution of sodium hyposulphite, as described on
page 94. The first reaction is expressed by the
equation :
C.H.-J3H -t- fiRr - C,n,Br,.On -J- SHBr.
Fio. 68.
94 480
As 480 parts of bromine thu;
correspond to 94
142 SAsr^i iff c9em:cai. asaltsis.
11 L V-r-Zl-t?- 1 -2*lTr;T -if :"l* Kr.-i. or ZZ: 1, TJtaiSiiTt^ ^JS&SUIT of iu
Tif^ LTi/'ii: r.i •wkr.^z ^cci'Lk:ry€>i ii* «»:«Ii:t}c«i« of earbTJie acid
';•- . V .-/i Li *i'- It- Til wii* C'f 'iil-inoi-m.^ ioh: tH-^'-iriM iht mixtare
:. ''*:t.»«**: •.:::- .: fr-T^ri:** :i:o *:■•••:■ liT^r^: li-e xTcer iarer will
Cr"I»,: ;*>\4.
L#'i- ;^^ s-jtrl-ei 71 : 'iV^ ir!?ns. of c»T:?:-^*-ri\>> "'ss^r?, or
^M litfirr, 'r-zi: rr-i- trirjlir orTft^'s: Trrr oeliiise^eni. and
i\,*^rr::'^* :rrr'^:;ei:lY : re**ri.::i;£: i rr-c*:«: iri^e^rsrce. 1:5 specific
jrriT.:- ^* -2.*i:- t: frv- C. ^^^ F. . A: Iv^?- C. 'S7i».4= F,) it
:i-*:>> : , k diri r^ l:-:::-!-!- wiicb. ozi c^r-xisc. s^.-Cidifies to a red-
d>i-l.iA-£. ^T?:;tIMT.e naaR. iari-.g & Eaetillic appeannce: at
•ci'-:»^rii:ir«- i'Mre r-V'^ C. (4-S"i* F. • ii i^ ce>>^rr.T>:ised intocbro-
:• . •-:! i^-,::-' :i:ir. Ct,0^ isd oxTzen : iCrO, « Cr,Oj + O^
C'-Txi:: fc-rri di*e.>".Te* readi'T ar.i w::r:ou* de<»nipa5inoD in
V b-.^r. xvi i '.-I'^i i'.<»bo'. aiii ir: pTi!v e:ber: :: a!^* oifisolTes in
z i-'-i i-.Tc^ : tv.d. itd in o^r:oe!::ri:c*i su.pnurio ac:i bat not in
* ^ \i'.'.rT TfLrrz. o''Dtair.57-g from 1»» lo 17 pe-r cen:, of water. Its
K t:: -1 :i Trt:»e:r. in m-h:cb 'be pr^seDo? of true ohn">m:c acid^
H/.V,*^ :^ fi.Si«-:!r.**i. i*, when concentrate*! of a ve'iowish -brown
'.-. .r. ••-":. '-f. zir.L^r d; lot -on. it assume* a mre vellow color, and
;, ^fcArr-i.^. ii i/r.d rea/rtior. ani an acid ai^d a>:rIr;ceDi ta^te.
Ci.'vri!; a?-d :• a rowerfu' oxMiziiii! ssren:. deeomnorine most
'rzail: •--.'•:»?: a i::>e-*. a^i r:«?v»:n:ng reA-li'r T>edaoe^I to chroinic
f-x: l^. Ti:t rr-:u:-::on ;» effe-rte^i by hydr«gen >'.Kphide, snlphur-
'. i* tii ir-^*",::*'!* acid*, as a!s«> bv various organic snKnances^
b':^:L i* rx's.'.:-: ;i^;:i sug^ir. I'arer. e!o, paricjlaKy on warming,
f T »i:':i '-ri-s::. its s-xutior. ca-jnoi bo f.'tered thr-^ugh paper.
I: strvii' i! >■:..; ti^ p>jre»i ip'^n tie acid, tbe a]c»nol becomes
fzTiitfr;. i-- :. TTiei: diss-V.ve^i in g'.yoerin. tie mixture explodes
v>/*ritiy ur.oi i^.tation.
W.ti IV ircei tr-roxide. chromic aci'i f -rms an intensely blue
frorr;>v-;i:. .:' i:: yet asoenaine-i cor.ir->s:ti'^n, which is very
'^i.«^a>/e: :: :> ^/r-bkr in water, and iiiiiv be extracted there-
frf>!r- by azi'^*:* i Tritb ether. A s«>p.:ewhat similar and much
jior*: jieri'.-i'rit I'.ie cjloration is produot-vi when an alcoholic
ACIDA. 143
tincture of guaiacum wood is added to a dilute aqueous solution
of chromic acid, and is best observed by allowing the liquids to
form two layers, when the coloration will appear at the point of
contact. By means of ihia easily applied reaction exceedingly
small amounts oT chromic acid ma? be recognized, although it
shuulJ be remembered that other oxidizing agents show a similar
behavior. An aqueous solution of chromic add, after the addition
of a few drops of hydrochloric acid and a few drops of alcohol,
aasumes, upon heating, a bright green color, with the evolution
of etherial vapors, A similar green coloration is immediately
produced by concentrated hydrochloric acid, or by the action of
the reducing agents previously mentioned, such as sulphurous
acid, hydrogen sulphide, ferrous salts, etc.
Examination:
Sulphuric acid may be detected by boiling a diluted solution of
the acid, to which a few drops of hydrochloric acid aud a little
alcohol have been added, until the liquid appears green, It is
then tested with barium chloride, when an ensuing white precipi-
tate will indicate the presence of sulphuric acid. Traces of sul-
phuric acid, from the difficulty of effecting its complete removal,
will usually be found, and the following test may serve to estab-
lish its limit for pharmaceutical application. One gram of chro-
mic acid is dissolved in 100 cubic centimeters of cold water, and
the solution mixed with 10 cubic centimeters of hydrochloric
acid; the further addition of 1 cubic centimeter of test-solution
of barium chloride should cause not more than a white turbidity.
Potassium bichromate or sulphate, which should not be present
ID any considerable amount, may be detected by igniting a por-
tion of the acid in a platinum crucible, and extracting the re-
xidual chromic oxide with boiling water. A portion of the neu-
tral solution is then tested with barium chloride, when a yellow
precipitate, insoluble in acetic, but soluble in hydrochloric, acid,
will prove the presence of chromate; another portion, previously
acidulated with hydrochloric acid, will, with the same reagent,
yield a white precipitate, if sulphate be present.
This hook is the proi^
COOPER MEDICAL
•* FRANCISCO
coll:.
anfi it> not tn 6* reiarwti />"in tha
Liln
. I ^i ••,'■(11) or
MANUAL OF CUEMICAL ,
ACIDUM Cn-RICtTM.
Oer. Citronrneaure ; Fr. Aride citrique ; Sp. Acido cEtrica.
CH.-CO~OH
C,H,0, + H.0 -
l/OR
I \co-on
+ H.O: 210.
On,-co-on
Colorless, rhombic prisms, wilh dihedral saminits (Fig. 69),
containing one molecule (8.6 per cent.) of water of crvstallizaiion,
and having the specific gravity 1,617. They are permaoent in
the air, but slightly cffloredcent in a dry aiid warm atmosphere.
and beuoming moist in a damp one, and
f lo. 89. posseos an agreeable, purely acid taste, and
Oan acid reaction.
The acid melta at 100° C. (212"' F.) in
its water of crystallization, and, when de-
prived of water, at 153 to 154'' C. (307.4
to 309.2° F.). Exijosed to a strong heat,
the acid first fuses, and afterwards becomes
decomposed, with the separation of carbon,
and the evolution of carboD monoxide,
carbon dioxide, acetone, and empvreuroBtio
acid vapfjrs, finally becoming wholly diaii-
pated. It dissolves in conceutraled sul-
phuric acid on gently warming, at first
without coloration, and wilh the rapid evo-
lution of carbon monoxide and carbon
dioxide gnscs, but afterwards becomes
blackened, with the development of sulphurous acid vapors.
Citric acid is soluble in 0.75 part of cold, and in 0.5 part of
boiling, water, in 1 part of alcohol at 15° C. (59° F.), and in 0.5
part of boiling alcohol, and in 48 parts of ether ; it is nearly in-
soluble in absolute ether, chloroform, benzol, and lienzin. Its
aqueous solution possesses a strongly acid taste and reaction, and,
when exposed to the air, is subject to gradual and spontaneous
change.
When citric acid, with about three limes its weight of nnamo-
Dia-water, contained in a seated tube, is allowed to repose for
some weeks al about 100° C. (212° F.), and the solution then
allowed to evaporate slowly in a shallow open vessel, it assumes
a beautiful deep blue color.
Citric acid forms no precipitate with potassium salts (except
the tartrates), and, when sparingly added to lime-water, so that
the alkaline reaction still predominates, it does not render it tnr-
AGIDA. 145
bid (distinction from oxalic, tartaric, and raccmic acids); when,
however, the liquid is warmed and agitated, it becomes turbid,
but transparent again upon cooling.
Examination :
In order to obtain an average sample of the crystallized acid
for examination, it is advisable to reduce to powder a consider-
able portion of the crystals, and to make from a small portion of
the powder two solutions: an aqueous one, in the proportion of 1
part of the acid to 2 parts of water; and an alcoholic one, in the
proportion of 1 part of acid to 4 parts of alcohol. Both the solu-
tions should be complete and clear.
Tartaric acid is detected by the formation of a granular white
precipitate, when 2 parts by measure of the above aqueous solu-
tion and 1 part by measure of the alcoholic solution are mixed
together, and agitated with 1 part by measure of a concentrated
solution of potassium acetate. The presence of more than 1 per
cent, of tartaric acid may be ascertained by the ensuing darkening
of the liquid within five minutes, when one gram of citric acid is
dissolved, without heat, in 10 cubic centimeters of a cold, satu-
rated solution of potassium bichromate.
When many samples of the crystallized acid have to be ex-
amined, the following method is alsp applicable :
A large glass pane is placed upon blue or dark-brown paper
on a horizontal table or board ; a solution of potassium hydrate
in diluted alcohol (1 part of dry potassium hyarate in 20 parts of
distilled water and 10 parts of strong alcohol) is then spread over
the pane as thick as will remain stationary upon it; a number of
crystals and fragments of the acid are now placed from one to
two inches apart, in this liquid, the crystals of each sample
separate. Instead of a glass pane, small plates may be employed.
Agitation being carefully avoided, the citric acid crystals, after
several minutes' action of the alkaline solution, appear clearer
and more transparent; if crystals of tartaric acid be present, they
will be recognized by their cloudy and white appearance ; after
two or three hours, the crystals of citric acid are nearly or quite
dissolved, and in their stead is frequently left a small, delicate,
dust-like spot (due to traces of calcium salts); if crystals of tar-
taric acid be present, they will appear whitish, covered with a
coat of small transparent acicular crystals, and surrounded by a
deposit of small overlapping groups of similar crystals, or a thin,
though broad, crystalline film (all crystals of potassium bitartrate).
Metallic impurities may be detected in the aqueous solution by
a dark coloration or turbidity with hydrogen sulphide; if it be so
considerable as to form a deposit, this is collected and washed
upon a filter, and then dissolved in a few drops of warm nitric
acid; to the obtained solution a few drops of dilute sulphuric acid
are added, when a white precipitate will indicate lead; after the
removal of the latter by filtration, the liquid, upon supersatura-
143 MANUAL OF ClIBMIOAL ANALYSIS.
tion with ammonia-water, will assume a blue color if~o^^er~i
present.
Sulpfiales may be delected in the diluted aqueous solution, to
which a few drops of diluted nitric acid have been added, by a
white precipitate with barium nitrate.
Oxalic acid will be indicated in the aqueous solution by a white
procipitatc, soluble in hydrochloric acid, upon the addition of n
solution of calcium sulphate.
Calcium salts, traces of which are usually present in the com-
mercial acid, will be detected bv the production of a white preci-
pitate or an opalescence upon tlie addition of a solution of ammo-
nium oxalate.
Estimation :
One hundred parts of citric acid neutralizfe (18.57 parts of dry,
anhydrous potassium carbonate, 142.85 parts of [Xjlassium bicar-
bonate, 204.28 parts of crystallized sodium carbonate, 120 parla
of sodium bicaroonate, and 68.20 parts of magnesium carbonate.
Citric acid may be estimated volnmetncally by means of a
standard solution of potassium or sodium hydrate, page 8", one
cubic centimeter of wtiich, if exactly normal, corresponds to 0.07
gram of pure crystallized acid ; or 8 5 grams of the acid abould
require for complete neutralization 50 cubic centimeters of the
standard alkali solution. The point of neutralization, as deter-
mined by litmus, is, however, in the case of citric acid not clearly
seen, and only approximately correct results can thus be obtained.
It may be more correctly estimated by the following gravimetric
process. A weighed quantity of the acid, or its aqueous solution,
IS carefully neutralized by ammonia- water, a slight excess of a
perfectly neutral solution of barium acetate added, and finally a
volume of 95 per cent, alcohol, equal to twice the volume of the
mixture. The precipitate is then collected on a filter (the weight
of the ash of which has been previously determined), washed with
63 per cent, alcohol, and dried at a mtjderate heat. The barium
citrate is then transferred to a porcelain crucible, the burned filter
added, aod, after the addition of a little concentrated sulphuric
acid, it is repeatedly ignited until the carbonaceous matter is
removed, and the entire amount of barium citrate has become
completely converted into barium sulphate. From the amount
of the latter its equivalent in citric acid may be readily deter-
mined ; 1 part of barium sulphate corresponding to 0.601 part of
cryslalliaea citric acid.
I
ACIDA.
147
Table of thtt parts hy weight of crystallized Citric Acid contained in
100 parts hy weight of aqueous solutions of the acid of different
specific gravities ( Gerlach).
Temperature 150 C. (590 F.).
Speetfte
Per cent, of
1
Specific Per cent, of
Specific
Per renr. of
1
citric acid.
graYlty.
citric acid. ,
23
gravity.
citric acid.
1.0037
1
1.0930 i
1.1947
45
1.0074
2
1.0972 24 i
1.1998
46
i.oni
8
1.1014 1 25 '
1.2050
47
1.0149
4
1.1060 26 I
1.2103
48
1.0186
5
1.1106 27 i
1.2158
49
1.0227
6
1.1152
28 '
1.22041
50
1.0268
7
1.1198
29 '
1.2257
51
1.0809
8
1.12439
30 1
1.2307
52
1 0350
9
1.1288
31
1.2859
53
1.08916
10
1.1388 ! 32
1.2410
54
1.0481
11
1.1378 ' 88 1
1 .2462
55
1.0470
12 i
1.1422 84
1.2514
56
1.0509
18
1.1467 35
1.2572
57
1.0549
14
1.1515
86
1.2627
58
10588
15
1.1564
37
1.2683
59
1.0682
16
1.1612
38
1.27382
60
1.0675
17
1.1661
39
1.2794
61
1.0718
18
1.17098
40
1.2849
62
1.0762
19
1.1756
41
1.2904
63
1.08052
20 '
1.1814
42
1.2960
64
1.0848
21 1
1.1851
43
1.3015
65
1.0889
22
i 1.1899
44
1.8071
66
ACIDUM GALLICUM
C.
Gallic 1
\cid.
Ger. Gallussanre ; Fr. Acide gallique ; Sp. Acido g&lico.
c,H.o.+H,o - c.n,<;g)^^H + ^'^^ ^**^'
Small acicular prisms or silky needles, or a crystalline powder,
nearly colorless, or of a pale fawn color, and containing 1 molecule
(9.57 per cent.) of water of crystallization. When heated to about
100° C. (212° F.) the acid loses its water of crystallization, at
about 200° C. (392° F.) it melts, and when heated to about 215^ C.
(419^ F.) it is resolved into carbon dioxide and pyrogallol or pyro-
gallic acid, which latter sublimes in small crystalline plates ; when
exposed to a strong heat, with free access of air, gallic acid burns
away without residue.
Gallic acid is soluble in 100 parts of cold and in 3 parts of boil-
ing water; in 4.5 parts of cold and in 1 part of boiling alcohol ;
in 40 parts of absolute ether; and is also sparingly soluble in
chloroform, benzol, benzin, and glycerin.
14!* MANUAt UF CHEMICAL AKALVS:
Tlie aqueous solution has an acidulous and nstringent t&Bta and
an acid renctiou, and is liable to apontaneuus decomposition on
exposure to the air; it gives no precipitate witli soliiliona of fer-
rous salts, if free from ferric salt, but it gives a bluish-black pre-
cipitate with solutions of ferric salts, the color of which disappears
wnen the liquid is heated, from ihe reduction of the ferric to fer-
rous salt, at the expense of the gallic acid. A solution of gallic
acid, when dropped into lime-water, produces a white turbidity,
which soon becomes blue, and passes tnrough a greenish or violet
tint to a purple color. The solution forms no precipitate with
argentic nitrate, but reduces it to metallic silver, gradually al
common temperatures, al once when heated.
Solutions of Ihe alkaline hydrates, as well as concentrated sul-
phuric and nitric acid, when poured upon dry gallic acid, dissolve
it, with a deep-red color.
Examinatioii :
Tnn7uc acid may be detected by a white precipitate, when the
solution of the acid is added to a dilute solution of gelatin, or by
a precipitate occasioned with solutions of alkaloids, albumen,
antimony and potassium tartrate with ammonium chloride, and
gelatinized starch.
Su'jnr and dextrin remain behind upon solution of the acid in
strong alcohol.
Resinous admixtures will remain undissolved, and float upon
the surface, when a small portion of the acid is dissolved in
boiling water.
ACIDUM HTDRIODICUH.
ACIDUM HYDlilODICUM DILUTUM.
ITydriodie Acid. Dilaltd Bydriedie Aeid.
Oer. .rodwMsereioSsauri! ; Fr. Acide liydriodique ; 8p. Acldo liidro!6d)co.
A clear, colorless liquid, which, when concentrated, possesses a
pungent odor, a strongly acid taste and reaction, and fumes by
exposure to the air. The acid, saturated at 0° C. (32° F.), has
the specific gravity 1,99. Such an acid, upon warming, develops
a large amount of hydrogen iodide, until the temperature of 55^
C. (131" F.) is atiaiued, and on further heating, in an atmosphere
of hydrogen (to prevent oxidation and liberation of iodine), the
temperature rapialy rises to 127° C. (260.6^ F.), when an acid of
constant composition distils over, having the specific gravity of
1.7, and containing 67.7 per cent, of hydrogen iodide. When a
weak acid is subjected to distillation, it loses at first principally
water, until at 127° C. (260.6° F.) an acid of constant composi-
lion dietilfl over, of the strength above mentioned.
ACIDA. 149
The diluted hydriodic acid has usually a specific gravity of
1.077 at 12 to 14° C. (58.6 to 57.2° F.), corresponding to 10.15
per cent, of true hydriodic acid.
Hydriodic acid in its aqueous solution rapidly undergoes oxida-
tion by exposure to the air, with the liberation of iodine, the
originally colorless solution assuming in consequence of the dis-
solved iodine a brown coloration, and will then iinj)art a blue color
to mucilage of starch, and a red or violet one to chloroform or
carbon bisulphide when agitated therewith. The dilute solution
of the acid assumes upon the addition of a few drops of concen-
trated nitric acid, or a little chlorine- water, a brown or yellowish-
brown coloration, due to the liberated iodine, which may be
recognized by its action upon starch, or by agitation with a few
drops of chloroform or carbon bisulphide as above described.
Hydriodic acid produces with a solution of argentic nitrate a
pale yellow precipitate of argentic iodide, which becomes but
slowly discolored by exposure to light, is nearly insoluble in ammo-
nia-water, and quite insoluble in dilute nitric acid ; with palladium
chloride it yields a black precipitate of palladium iodide, insoluble
in nitric acid; and with plumbic acetate a bright yellow precipi-
tate of plumbic iodide, which is insoluble in cold, but soluble
in hot water, and in a solution of potassium iodide or sodium
hydrate.
" Examination :
The acid should be colorless or nearly so, and when a portion is
evaporated in a small porcelain ca})sule, at a gentle heat, it should
leave no residue (absence of phos})horic acid ov fixed imj^urides).
Hydrochloric acid may be detected by completely precipitating
a small ))ortion of the acid with argentic nitrate, collecting the
precipitate upon a filter, and digesting it with ammonia-water;
the ammoniacal solution is then filtered, and supersaturated with
nitric acid, when a white precipitate will indicate hydrochloric
acid.
Ilydrohromic add may be detected by completely precipitating
a small portion of the acid with palladium chloride, filtering the
solution from the precipitate of palladium iodide, and adding
thereto a little chlorine-water; if hydrobromic acid is present
bromine will be liberated, imparting a yellow color to the solution,
as well as to a few drops of carbon bisulphide or chloroform, sub-
sequently added and agitated with the same.
IJydrofjen sulphide will be recognized by a brown or blackish
coloration on the addition of a solution of plumbic acetate.
Estimation :
The strength of aqueous hydriodic acid may be determined by
ascertaining its specific gravity, and reference to the subjoined
table, or more accurately estimated by the following methods:
I. Volumetric. — (1) About 20 grams of the acid arc weighed in
a beaker, diluted with a small amount of water, a few drops of
150 MANUAL OP CHEMICAL ANALYSIS.
litmus solution added, and a normal solution of potassium or sodium
hydrate (page 87) allowed to flow into the liquid from a burette
until a permanent blue coloration is produced. One cubic cen-
timeter of the normal alkali corresponding to 0.128 gram of abso-
lute hjdriodic acid, HL the percentage strength of the acid may
be readily calculated.
(2) The acid may be likewise estimated volumetrically by means
of a standard decinormal solution of argentic nitrate, page 98 ;
one cubic centimeter of the argentic nitrate solution correspond-
ing to 0.0128 gram of absolute hydriodic acid, HI.
II. Gravimetric, — A weighed portion of the acid is completely
f)recipitated by a solution of argentic nitrate, the precipitate col-
ectea upon a filter, well washed with water, and, after drying,
heated in a weighed porcelain crucible at a temperature just suf-
ficient to fuse the argentic iodide. The crucible and its contents,
after cooling, are again weighed, and from the weight of argentic
iodide the amount of hydriodic acid is calculated; 100 parts by
weight of argentic iodide- corresjx>nding to 54.46 parts of absolute
hydriodic acid, HI.
Tahle of the parts by weight of Hydriodic Acid contained in 100 parts
by weight of aqueotii acid of different specijic gravities {Topsot),
Temperatare 12 to U- C. (53.6 to 67.2- F.).
SpM^ifle
Per c*ot. of
Bp^fiflr
Per cent, of
Sperlflc
PereeBt.uf
gr»\uj.
UI
2.286
gravity.
1.253
HI.
grwLMij.
UI.
1.017
28.41
1.542
49.13
1.0.52
7.019
1.274
80.20
1.572
50 75
1.077
10 15
1.309
83.07
1.603
52.43
1.095
12.21
1 347
36.07
1.6:i0
53.93
1.102
13 09
1.382
38.68
1.674
56.15
1.126
15.73
1.413
40.45
1.696
57.28
1.164
19.97
1.451
43.39
1.703
' 57.43
1.191
22. C:^
1.486
45.71
1.706
57.64
1 225
25.86
1.528
48.22
1.708
57.74
ACIDUM HTDROBROMICUM.
ACIDUM HYDROBROMICUM DILUTUM.
Ilydrobromie Acid. Diluted Hydrobromie Acid.
Gcr. BroinwawMfrsloffsaure ; Fr. -\cide hydrobromique ; Sp. Acido
bidrobr6mico.
A clear. color)i*s.s and, when concentrated, pun«rent and strongly
acid liquid, which does not readily undergo change by exposure
to the air. When saturated at 0° C. (32^ ¥.\ it has a specific
gravity of 1.7^, and contains 81 to 82 jMsr cent, of hydrogen bro-
ACIDA. 151
mide. Such an acid fumes oa exposure to the air, and, when
subjected to distillation, develops hydrobromic acid gas, until at
125 to 125.5° C. (257 to 257.9^ F.) an acid of constant composition
distils over, having the specific gravity of 1.49 at 14° C. (57.2°
F.), and containing 48 per cent, of hydrogen bromide. When a
weak aqueous acid is subjected to distillation, it loses water, until,
like hydrochloric acid, at a definite temperature, 125 to 125.5° C.
(257 to 257.9° F.), an acid of constant composition distils over,
which, however, is subject to variation in strength in accordance
with the atmospheric pressure.
The diluted hydrobromic acid (Acidum Hydrobromicum Dilu-
tum, U. S. P.) has the specific gravity of 1.077 at 15° C. (59° F.),
corresponding to 10 per cent, of absolute hydrobromic acid. Hy-
drobromic acid yields with argentic nitrate a yellowish-white
precipitate of argentic bromide, which becomes but slowly dis-
colored by exposure to the light, is insoluble in dilute nitric acid,
and sparingly soluble in ammonia- water, but dissolves readily in
a solution of potassium cyanide ; with palladium nitrate (but not
with the chloride) it affords a reddish-brown [)recipitate of palla-
dium bromide ; and with solutions of plumbic or mercurous
nitrates, white precipitates of plumbic or mercurous bromide,
which are sparingly soluble in water. From a dilute solution of
hydrobromic acid or a soluble bromide, no bromine is liberated on
the addition of a few drops of concentrated nitric acid (distinction
from hydriodic acid and iodides); chlorine- water, however, when
mixed with the aqueous solution of the acid, liberates bromine,
which imparts a reddish-yellow color to the liquid, and, upon
subsequent agitation with a few drops of chloroform or carbon
bisulphide, it is absorbed by the latter with an orange-yellow
color.
Examination :
The acid should be colorless, and, when a portion is evaporated
in a small porcelain capsule, at a gentle heat, it should leave no
residue (absence of phosphoric acid ov fixed impurities).
Bromine, — The presence of bromine will be indicated by a yel-
low or reddish-yellow color of the liquid, and, when shaken with
a few drops of chloroform, will impart an orange-yellow color to
the latter.
Iodine and Hydriodic Acid, — Free iodine may be detected by
agitating a small portion of the acid with a few drops of chloro-
form, when the latter will assume a violet coloration. Hydriodic
acid may be detected by the formation of a black* precipitate of
palladium iodide, on the addition of a solution of palladium chlo-
ride ; or, by an ensuing turbidity, when 5 drops of the acid are
mixed with 5 cubic centimeters of water and an equal volume of
stronger ammonia-water, one drop of solution of argentic nitrate
added, and the whole well mixed.
Hydrochloric acid may bo detected by neutralizing the acid with
152
MAMIAL OF CQtlMICAL ANALYSIS,
»
Ijarvta-water, evaporating the solution to ilryness, i|?niting tha
residue, and finally extracting with absolute alcohol. The barinm
bromide will become thereby completely dissolved ; should a
residue remain, it is dissolved in wat«r, the solution acidulated
with nitric acid, and tested with solution of argentic nitrate, when
a white precipitate, soluble in ammonia-water, will prove the
presence of hydrochloric acid.
Sulphuric acid will l)e recognized by a white turbidity or nre-
cipitiite when a dilul« solutiou of the acid is tested with barium
chloride or nitrate.
Sulp/iuroiis Aciil. — A small portion of the acid is added to a few
fragments of pare metallic zinc in a test-lube, and a small pieue
of bibulous paper, moistened with a solution of plumbic
Fio. 70. acetate, placed over the mouth of the lube (Fig. 70);
a discoloration or production of a black stain upon the
paper will prove tlie presence of sulphurous acid.
Sfetaliie ivipuritifs may be detected by a dark colora-
tion or a precipitate, upon salurating a dilute solution
of the acid with hydrogen sulphide, or upon the subse-
quent additicm of ammonium sulphide.
Estimation:
The strength of aqueous hydrobromic acid may be
determined by ascertaining its specific gravity, and
reference to the eubjoincd table; or more accurately
estimated by the following methods:
I. Volumetric. — (1) About 20 grams of the acid are
weighed in a beaker, diluted -with a small amount of
water, a few drops of litmus solution added, and a nor-
mal solution of potassium or sodium hydrate (page 87)
allowed to floiv into the liquid from a bureite until a
permanent blue coloration is produced. One cubic
centimeter of the normal alkali corresponding to 0.081
gram of absolute hydrobromic acid, IlBr, the percent-
age strength of the acid may be readily calculated.
To neutralize 16.2 gram of the offiemal acid should
require 20 cubic centimeters of normal solution of
potasiiium or sodium hydrate,
(2) The acid may be likewise estimated volumetri-
oally by means of a standard deoinomial solution of argeutio
nitrate, page 98; one cubic centimeter of the argentio nitrate
solution cor res lion ding to 0.0081 gram of absolute hydrobromic
acid. HBr.
II. Gravimetric. — A weighed jwrtion of the acid is completely
fireci pita led by a solution of argentic nitrate, the precipitate cof-
cctcd upon a filler, well wa.-fhed with water, ana, after drying,
healed in a weighed porcelain crucible at a temperature just
sufGeient to fuse the argentic bromide. The crucible and its
contents, after cooling, are again weighed, and from tlie weight of
ACIDA
153
argentic bromide the amount of hydrobromic acid is calculated ;
100 parts by weight of argentic bromide corresponding to 43.08
parts of absolute hydrobromic acid, HBr.
Table of the parts hyweight of absolute Ht/drohromic Acid contained in
100 parts by weight of aqueous acid of different specific gravities (Biel).
Temperature 150 C. (51P P.).
1
Per cent, of
i
Per c<*nt. of i
Per cent, of
8i»eciflo gravity.
HBr.
Specific gravity.
1 •
HBr. ,
Speclflo gravity.
HBr.
1.0082
1
1.145
18
1.314
85
1.0155
2
1 1.154
19
1.326
36
1.0230
3
1 1.163
20 1
1.338
37
1.0305
4
1.173
21
1.350
88
1.038
5
! 1.181
22
1.302
89
1.040
6
' 1.190
28
1.375
40
1.058
7
,' 1.200
24 !
1.388
41
1.061
8
1.209
25
1.401
42
1.009
0
' 1.219
26 '
1.415
43
1.077
10
1.229
27 1
1.429
44
1.085
11
1.239
28
1.444
45
1.0U3
12
1.249
29
1.459
46
1.102
13
1.260
30
1.474
47
1.110
14
1.270
81
1 400
48
1.119
15
1.281
82 1
1.496
49
1.127
16
1.292
33
1.513
50
1.136
17
1.303
84
ACIDUM HTDROCHLORICUM.
ACIDUM MURIATICUM.
Ilydrochloric Acid. Muriatic Acid,
Ger. Salzsaure, Chlorwasserstoffsiiure ; Pr. Acide hydrochlorique ;
8p. Acido hidrocl6rico.
Concentrated hydrochloric acid is a colorless fuming liquid,
of a pungent and suffocating odor and corrosive acid taste ; its
specific gravity depends upon the quantity of hydrogen chloride
held in solution, and varies in the strong acid between 1.1()0 and
1.120, corresponding to 32.21 and 24.4G per cent, of absolute hydro-
chloric acid.
The crude commercial acid has generally a spec. grav. of from
I.IGO to 1.180, containing 32.21 to 30.21) per cent, of the gas,
together with various impurities, such as sulphuric and sulphurous
acids, chlorine, iron, and organic matters (the two latter of which
impart a yellowish color to the acid), and also frecjuontly arsenic.
Two strengths of hydrochloric acid are officinal: Acidum
Hydrochloricum of the spec. grav. I.IG (1.10 Brit. Pharm. =32.21
per cent. HCl,and 1.124 Pharm. Germ.aa25 per cent. IICl), contain-
liii MANUAL OP CHBMICAL ANALYSIS.
ing 82.21 p(jr cent., nnd Acidum Hydroclilorioum Dilutum of toe
s]ieo. griiv. 1.04a {1.052 Brii. Pharm.= 10.0 per cent. HCl, and
1.061 Pharra. Germ.™ 12.5 |x;r cent. HCl), containing 10.10 per
cent, of abnolute hydrochloric acid.
Hydrochloric acid may be recognized by the formation of a
white, curdy precipitate on the addition of a solution of argentic
nitrate; the precipitate is insoluble in nitric acid, but soluble in
ammonta-waler and in solutions of potassium cyanide and sodium
hyposulphite, and assumes a violet or blackish-brown color on
exposure to solar light. The acid may also be reoognizeil by the
evolution of chlorine gas, when heated in a, test-tube with a Utile
manganese dioxide.
Examination:
Fixed impurities are recognized by a residue, upon evaporation
of the acid in a watch glass. To determine the nature of such a
residue, whether organic or inorganic, or the possible presence of
substances of both classes, it should be strongly heated on plati-
num-foil or in a small porcelain crucible, when organic matters
will burn entirely away, while moat inorganic substances leave a
permanent residue.
Sul/iiiuric aciil may be detected in the acid, after dilution with
at least five times its volume of water, by the formation of a while
precipitate, either immediately or upon standing, on the addition
of solution of barium chloride.
Sulphuroua acid may be detected in the filtrate of the preceding
test, after the sulphuric acid, if such be present, has been com-
pletely eliminated, by mixing with it a little chlorine-water; an
ensuing white turbidity would indicate sulphurous acid.* This
may alsti be recognized or confirmed when to a little of the hydro-
chloric acid, diluted with 4 or 5 parts of water, a perfectly clear
and saturated solution of hydrogen sulphide in water is added;
an ensuing white turbidity or opalescence, due to the separation
of sulphur, will, in the absence of ferric salts, likewise indicate
sulphurous acid.
Another very reliable test for sulphurous acid, and which will
at the same time detect the presence of arsenic, consists in adding
to a portion of the acid, diluted with an equal volume of water,
in a teal-tube, a few fragments of pure granular zinc, and cover-
ing the orifice of the lube with a small cap of bibulous paper,
moistened with a solution of plumbic acetate (Fig. 71); or, if it is
desired at the same lime to test for arsenic, a cork provided with
two strips of bibulous pajjer, as shown in the figure, one of which
is raoisiened with a soluiioo of plumbic acetate and the other with
a solution 'of argentic nitrate, is loosely inserted in the mouth of
the tube,
* Clilorine nnA nulphtimne acids, when in couIhci nlih water, form bydro-
cliliirlc inid Ruli>liuric addsi ilierpfori' \\k pretence of eiilier one at Uieae
impiirllles in hjrdmclilorlc acid cxciudea tlie otber one.
Fio. 71.
ACIbA. 1A6
of sulphurous acid, hydrogen sulphide will be
developed, and produce a blackening of both strips of paper,
whereas, if arsenic alone be present, only the one moistened with
the argentic solution will become discolored.
Chlorine may be detected by the occurrence of a blue coloration,
when ihe acid, diluted witli about five times its bulk of water, is
mixed wilh a few drops of solution of potassium iodide (free from
iodate) and a little mucilage of starch; or by imparting a violet
color lo chloroform or carbon bisulphide, when agitated therewith,
after the addition of a few drops of solution of
potassium iodide.
Iodine and Bromine. — About eight volumes
of the aoid are aj^itated in a test-tube with
one volume of chloroform ; after subsidence,
the stratum of chloroform will appear red
when iodine, and yellowish when oromine,
ia prefwnt. If the chloroform, however, re-
mains colorless, a few drops of chlorine- water
are added; when, after agitation and subse-
quent subsiding, the chloroform still remains
colorless, the absence of hydrobromic and of
h^driodic acids is also proved.
MetaU are detected in the acid, diluted with
at least four times its bulk of water, when
tested with hydrogen sulphide: a white tur-
bidity would indicate sulphurous acid or ferric
chloride, a yellow one, arsenic, and a dark one,
copper, lead, or tin. In order to distinguish
the latter, the precipitate is collected upon a
filter, washed, and then treated with a little
warm ammonium sulphide; the sulphides of
tin or arsenic would become thereby dissolved,
and, af\er their removal b^ filtration, may be
separated by again precipitating them from
their solution by hydrochloric acid, and digest-
ing the resulting precipitate with a concentrated solution of ammo-
nium carbonate, when the arsenic is redissolved, and upon the
addition of hydrochloric acid in excess ia obtained as yellow
arsenious sulphide, whilst the tin by digestion with the ammo-
nium carbonate solution remains undissolved as yellow stannic
sulphide. The portion of the original precipitate insoluble in
ammonium sulphide is washed with water upon the filter, and
dissolved in a small quantity of warm nitric acid. To this solu-
tion a few drops of dilute sulphuric acid are added, when awhile
grccipitate will indicate "fe«</; after the removal of the latter by
Itration. if present, ammonia-water in slight excess is added,
when a blue coloration will indicate copper.
Iron may be detected in the acid, after its previous dilution with
156 MANUAL OF CHIiUICAL ANALYSIS.
a little water, by a blue coloration or precipitate on the addition
of solution of potassium ferroeyaaide, or by a red coloralitm oa
tlie addition of potassium aulphocyanide.
-Arsenic— The presence of arsenic, if sulphurous acid is absent,
will have been indicated by the previously described test for the
latter, page 154; it may also be recognized by the addition of a
few drops of a saturated ttulution of stannous chloride, or a strip
of pure tin-foil and a little pure concentrated sulphuric acid, to
the concentrated acid, in a teat-tube, and warming very gently. If
artrenic be present, brown flakes will be deposited, or, if the amount
be very small, only a brown coloration of the liquid will ensue.
The recognition of very small quantities of arsenic may be best
accomplished by the application of Marsh's test, as described on
pages 33 to 36.*
Estimation :
The estimation of pure hydrochloric acid is most conveniently
accomplished volumolricallv by the process of neutralization.
About 5 grams of the acid are accurately weighed in a small
beaker, diluted with a small amount of water, a few drops of
litmus solution added, and a normal solution of potassium or so-
dium hydrate (page 87) allowed to flow into the liquid from a
burette until, with eonstaul stirring, by means of a glass rod, the
liquid assumes a permanent blue tint. One cubic centimeter of
normal alkali solution corresponding to 0.03ti5 gram HCI, cor-
rected if necessary by its proper factor, the number of cubic cen-
timeters employed will at once indicate by simple calculation the
amount of absolute hydrochloric acid in the quantity of liquid
taken, and from which its percentage strength may then be cal-
culated. For the confirmation of the correctness of the result
the specific gravity of the acid may be taken, and compared with
the strength of that indicated in the subjoined table, page 158.
Hydrochloric acid may alsii be estimated vo!u metrically by the
process of precipitation. About one gram of the acid is first
accurately weighed in a beaker or small flask, subsequently
diluted with from bO to 100 cubic centimeters of water, and, after
exact neutralixalion with pure sodium carbonate, and the addition
of a few drops of a solution of potassium chromate, as an indi-
cator, a decmormal solution of argentic nitrate (page 98) is
allowed to flow into the liquid from a burette until, with constant
stirring, by means of a glas.s rod, a permanent red coloration is
produced. One cubic centimeter of decinormal argentic nitrate
• In Uie opplleallon of llie Rbnve rcatB for arsenic, snlpbamus nctd'sUoiild be
excluded, NB, in tli^ flr«l metniKie. U proiluces of ilself willj staniioiia clilorlde
a Tdlnwiili or l]rr>wn col r>ni lion, an<1. lit the second Instance, by the fiirmation
nf byAragen iiilphlde in oDlact witii nnscenl hydms^n, the arsenic wnnld be
deposiled ns inBOlulile BreenimiB 8iil|ibide ; when sulpliuniua ftcid is present. It
Klimild, Ihereforc, flrsl be climinntcd by Ihe mldlliDn ofn very small quAQtily of
II )o1utii)n or iodtue iu potassium iodide, wlica the teBln as desorilwd may \x
Applied.
ACIDA. 157
solution corresponding to 0.00365 gram HCl, this number, when
multiplied by the number of cubic centimeters of silver solution
employed, will represent the amount of absolute hydrochloric
acia in the quantity under examination, from which the per-
centage strength of the acid may be readily calculated.
The estimation of hydrochloric acid may be also accomplished
gravimetrically, by adding to a weighed portion, diluted, if neces-
sary, with water, a solution of argentic nitrate until no further
precipitate is produced, and subsequently rendering the liquid
slightly acid, by the addition of a few drops of nitric acid. The
precipitate of argentic chloride is collected on a tared filter,
washed with water, and, after drying at 100° C. (212° F.) until
of constant weight, weighed ; or, the dried precipitate, if sufficient
in amount, is brought into a small, previously weighed porcelain
crucible, and ignited at a gentle heat. 100 parts of argentic
chloride correspond to 25.43 parts of absolute hydrochloric
acid, HCl.
Rules for the dilution of Hydrochloric Acid,
For the purpose of diluting a concentrated acid with water, or
with a weaker acid, in order to obtain an acid of some special
strength, the following simple and concise rules are applicable
and convenient : —
If a stronger acid (a) is to be diluted to form an acid of the
strength {h) by mixing it with water, or with a weak acid (c), the
difference in percentage strength is sought, on the one hand,
between a and ^, and, on the other, between b and c, and a and c
are then mixed in the proportion shown by the difference in
the numbers. It has, however, to be taken into consideration that
when the difference between a and h is greater than between h and c,
less must be taken of a than of c in order to obtain h; but when
the difference between a and h is less than between h and c, more
must be taken of a than of c in order to obtain h.
Example:
I. Hydrochloric acid, containing 29 per cent. HCl, is to be
mixed with water to form an acid containing 25 per cent. HCl :
(«) (i) (c)
29 per cent. 25 per cent. 0 per cent.
Difference 4 25
Accordingly 25 parts of the 29 per cent, acid are to be mixed
with 4 parts of water,
or 100 grams Hydrochloric Acid =» 29 grams HCl
16 grams water «■ —
116 grams Hydrochloric Acid ■= 29 grams HCl
or 100 grams ** ** «■ 25 grams "
158 MASUAl. OP CUEMICAL ANALYSTS.
m
n
II. Hydrochloric acid, containing S2 per cent.
HCl, is
to be I
mixed with an acid containing 8 jjer cent. HC!, to form an acid ■
containing li per cent. HCl.
(a) (A) (c)
39 per cent. 14 per cent. 8 per oen
18 6
Difference (3) (1)
Accordingly 1 part of the 32 per cent, acid is to be
mixed
with 3
parts of the 8 per cent, acid,
or 100 grama Hydrochloric Acid « 32 grams
HCl
300 grams " " — 24 "
400 grama Hydnwhloric Acid = 56 grams
~Hci
or 100 grama " " « 14 gram
"
Table of the quantity by weight of Hydrochloric Add Gai, and the ear. H
retpondiug equivalent of Chlorine, eontaiiied in 100 part» by teeiyht oj H
Aqtteoa* Hydrochloric Acid of dij>Te>tl ipecifc gravitiei (Ure). |
Temperalure 150 C. (50° F.).
Par el. at
Fareggi.
P»r ct, or
P.r csul
PfT Cl. of
Par swt.
gparllld
hjdroclil
hj-drochl
8ii»flBc
by.lr^cbl
or
jr..l.7.
chlBrIn,.
gnullj.
■u.ld.
gnvlij.
ehlurJga
1.3000
40.777
80.675
1.1338
36.918
36.186
,' 1,0637
18.048
13,807
i.niBa
40.300
80.376
1,1306
26.545
35.789
1 1.0817
12.041
13.800
MB81
39.061
88.883
1.1387
Sfl.OflS
35.3B3
1.05BT
13,383
I1.B03
1.1046
80.S54
38.485
1.1367
35.6B0
34,906
l.a577
11.835
11.606
1.1938
39.146
38.080
1,1247
35.!i83
24.5BB
1.05.57
11,418
11.109
I.IBIO
38 738
37.0B3
1.13^7
34.874
34.203
1.0587
11,010
10.713
1.18(13
38 3!I0
87.3H0
1.1308
24,408
33.805
1.0517
10.003
10.810
1.1875
37.03»
86.900
1,1185
34.058
33.408
1,0497
10,194
9.010
1.18.17
87,516
36.503
1,1164
33,650
23,013
1.0477
9,786
0.533
1.1840
37.108
38, 107
1. 1143
33.343
33.015
1.0457
9 379
9,128
1 1833
88.700
85.707
1.1133
33 834
33.318
1.0487
8,071
8.720
1.1M3
80.303
85 810
1.1103
23,436
31.833
; 1,0417
8,608
8.383
1.1783
3.1.684
84,913
1.1083
23.010
21.43S
1 1.0397
S.155
7.885
1.1768
85.476
34,617
1.UI61
31.611
31,038
1,0377
7.747
7.588
1.1741
85-008
84.131
1.1041
21.304
20.683
1 08.17
7.340
7.141
1.1731
84.800
83.r24
I 1020
20.700
30.235
1,0337
6 033
«.74il
1.170!
34.259
88.838
1.1000
20.888
19.837
1.0318
8.524
0.848
1.1081
83.845
33,031
1.0080
18,980
18.440
1.03H8
8,118
0.8C1
I.IMI
88.437
83,-585
1.0000
IB, 673
18.044
1.0370
5.700
S.5M
1.1041
83.030
32,136
l,098B
IB. 105
18.047
1.03,50
6.301
6.188
1.1030
83.631
31.745
1.0019
18.757
18.250
1.0239
4,8B4
4.703
J.159B
33.313
81,348
1.089fl
18.S4B
17 8.54
1,0230
4.480
4.865
1.1578
31.805
80.1140
1,0878
17,B4I
17.437
1,0300
4.078
8,888
1.1557
81.3D8
80.650
1.08.5B
17- .584
17,000
1.0180
3,870
8.671
n i.im
8O.01W
30.1.'j8
1.0838
17.128
18.800
1.0160
8-363
8.174
L l.UU
80.583
39.757
1.0818
10 718
10,267
1.0140
3.~54
9.778
1 1.1404
30.174
SB. 361
1.0708
tU.310
15.870
1.0130
2.447
3.381
1 1.I47S
30.767
38 004 j
1.0778
IBBOa
15.474
I.OIOO
3.089
1.B84
r 1.1453
30 350
38.587
1.0758
15.404
16.077
1,0080
1.631
1.6W
i.uai
88.051
38.171
1.0738
15.087
1 4,. 580
1.0080
1.134
l.IOl
I.UIO
38.644
37.773 .
1.0718
14,070
14.284
1.0040
0,818
0.785
1.1389
38,186
37,878
1,0807
14,271
13,887
1,0030
0.408
0.B87
1.1 HOB
27.T2S
26.070 :
1.0677
18.883
13.490
1.1849
37.831
38.588
1,0657
18.4S7
18.084
^B k ^^^1
ACTDA. 159
The specific gravity of the aqueous acid being decreased by an increase of
temperature, and increased by a decrease of temperature, the consequent change
of the specific gravity amounts for each degree of the centigrade thermometer
in either direction —
For acids of a specific gravity of 1.1741 to those of 1.1889 to about 0.0005
*♦ ** " 1.1349 ** 1.0980 ** 0.0004
•* *« »* 1.0989 " 1.0087 ** 0.0003
For in$tane$ : An acid of a specific gravity of 1.1234 at 160 C, containing 25
per cent, of hydrochloric-acid gas, will have at 18.5° C. a specific gravity of
1.1234 — (0.0(K)4 X 2.5) = 1.1224, and at 13.50 C. a specific gravity of 1.1284 +
(0.0004 X 2.5) s 1.1244.
ACIDUM HTDROCTANICUM DILUTUM.
ACIDUM HYDROCYANATUM.
Diluted Hydrocyanic Acid, Prussie Acid.
Ger. Cyanwasserstoflsaure, Blausaure ; Fr. Acide hydrocyanique ; 8p. Acido
hidrocianico^
Pure hydrocyanic acid is a thin, colorless, and exceedingly poi-
sonous, volatile, and unstable liquid. Its odor is very powerful
and characteristic, resembling that of peach-blossoms or oil of bitter
almonds. It mixes with water, alcohol, and ether, in all propor-
tions. The officinal acid is a very dilute hydro-alcoholic solution,
containing two per cent, of absolute acid. It imparts a faint eva-
nescent color to litmus, and forms a white curdy precipitate with
a solution of argentic nitrate. This precipitate is soluble in solu-
tion of potassium cyanide, ammonia-water, and boiling nitric acid,
but insoluble in dilute acids, and does not readily change color on
exposure to solar light; when strongly heated it is completely
decomposed into metallic silver and cyanogen gas. If the acid is
rendered slightly alkaline by potassium hydrate, a few drops of a
solution of ferrous sulphate and ferric chloride added, and the
mixture subsequently acidulated with hydrochloric acid, a pre-
cipitate of ferric ferrocyanide or Prussian blue will be produced.
Hydrocyanic acid may also be recognized by the following
characteristic reactions. When neutralized with a dilute solution
of potassium or sodium hydrate, a few drops of yellow ammonium
sulphide added, and the mixture carefully evaporated in a porce-
lain capsule to dryness, a residue is obtained which, when dis-
solved in water, acidulated with hydrochloric acid, and filtered,
yields on the addition of a drop of solution of ferric chloride an
intense blood-red color. When the acid is neutralized with a
dilute solution of potassium or sodium hydrate, a little picric acid
added, and the mixture warmed, an intense blood-red color, due
to the formation of picrocyanic acid, CgH,N30j, is produced. If
a solution of mercurous nitrate is added to a solution of hydro-
cyanic acid, a gray precipitate of metallic mercury is at once pro-
I
AN'ALYBIB.
ducc'i, with the simultuneous fonnalion of mercuric cjanide,
which rcinaiiis iu solutiou.
Examination :
A sTniill [inrtion of the acid, when allowed to evaporate on n
watch glass, should leave no residue.
Mineral amis in general may be detected by producing a per-
manent red coloration with litmus, as also by causing the precipi-
tation of red mereuric iodide upon the addition of a solution of
the double salt of mercuric cyanide and potassium iodide,
IIgK(CN)J,* the latter being decomposed by all acids, with the
exception of hydrocyanic and carbonic acids.
Hydrochloric and phosphoric acids may be detected by the addition
of an excess of ammonia- water, and evaporating the solution in a
porcelain capsule, at a gentle heat, to dryness; the residue is dis-
solved in dilute nitric acid, and a portion of the filtered solution
examined with argentic nitrate for hydrochloric acid, which is in-
dicated by a white precipitate. To another portion of the solu-
tion ammonium molybdate is added, and heated to boiling; an
ensuing yellowish precipitate indicates phosphoric acid.
formic acid, if present, will be detected by its property of
reducing red oxide of mercury to gray metallic mercury, when a
little of the acid is warmed and agitated with the oxide; or by
the reduction of oietallic silver on the addition of a solution of
argentic nitrate, which will impart a grayish color to the precipi-
tated argentic cyanide.
Sulphuric and is detected by the formation of a white precipi-
-tatenpon the addition of a few drops of barium nitrate to the acid.
Estimatioa of the Strength of Hydrooyanio Aoid :
There are two simple methods of ascertaining the quantity of
absolute acid contained iu hydrocyanic acid. The one depends
upon the fact that one part of absolute hydrocyanic acid forms 5
parts of argentic cyanide; that, accordingly, 100 parts of the
officinal acid should yield 10 parts of argentic cyanide.
The second method is the volumetric one, and dejwnds npon
the property of argentic cyanide to form a soluble double salt
with alkaline cyanides. When, therefore, the officinal hydro-
cyanic acid is converted into sodium or potassium cyanide by the
addition of sodium or potassium hydrate, no permanent precipi-
tate will appear upon the addition of argentic nitrate until more
than sufficient argentic cyanide is produced to form the soluble
compound.
I. Ten grams of the acid are completely precipitated by a solu-
tion of argentic nitrate. Then two li Iters of exactly the same size
and pajjcr are cut; through the one the liquid is Bltered, the pre-
• Ohtained by mixhifr hnt cnncentrsied nlcoliolic boIuIiodb of 8 parta nf mer-
caric cynnldv itnd 2 parts i>f poinBgium iodide : llie compoiiDil crjHiallizes oat
uiton cooling, aud may \te dlasolved in WHi«r lur ubc.
ACIDA. 161
cipitate washed, and then both the empty filter and the one con-
taining the argentic cyanide are dried, at a temperature not
exceeding 100° C. (212° F.). When the weight of the latter filter
remains constant, both filters are weighed, the empty one serving
as a counterpoise of the one containing the precipitate; the
excess of weight of the latter is argentic cyanide, of which —
1. grnm represents 2.015 per cent, of absolute hydrocyanic acid.
1.05 •* »' 2.10 •*• »*
1.10 " ** 2.20 '* ** **
II. The principle involved in the volumetric estimation of
hydrocyanic acid has been fully described on page 100. 5.4 grams
of the acid are accurately weighed, and diluted, in a beaker, with
about 200 cubic centimeters of water. The liquid is then made
slightly alkaline with a solution of potassium or sodium hydrate,
a few drops of a saturated solution of sodium chloride added, and
a decinormal solution of argentic nitrate (page 98) allowed to flow
into the liquid from a burette until, with constant stirring, a slight
permanent turbidity is produced in the solution. Tlie number of
cubic centimeters of silver solution required to produce this reac-
tion with the above-mentioned quantity of acid, divided by 10,
will give at once the percentage strength of the acid in hydrogen
cyanide.
Separation and Detection of Hydrocyanic Acid in Forensic Inves-
tigations.— Hydrocyanic acid, being one of the most formidable of
poisons, is sometimes the object of search in forensic investiga-
tions, and the process for its isolation, and subsequent recognition
and estimation will, therefore, be briefly described.
The organic materials or substances to be examined are brought
into a flask, a little water added, if necessary, and the mixture
slightly acidulated with tartaric acid. A preliminary test is then
first made by inserting in a cork adapted to the flask containing
the mixture a small strip of paper, moistened first with a little
tincture of guaiac, and, after drying, with a very dilute solution
of cupric sulphate,* and subsequently gently warming the mix-
ture to about 50° C. (122° F.). In the presence of the vapor of
hydrocyanic acid the paper will assume a deep blue color. As,
however, other substances, ammonia, nitric oxide, etc., are capable
of producing a similar blue coloration, this reaction does not afford
unqualified proof of the presence of hydrocyanic acid ; and when
thus indicated by the above reaction, or by the odor of the mix-
tare under examination, the isolation and identification of the
acid must in all cases be effected.
♦ The tincture of gnaiac is best freshly prepared^, in the proportion of one
part of the wood to ten parts of alcohol, or one part of the resin lo twenty
parts of alcohol ; the solution of cupric sulphate in the proportion of one part
of the salt to two thousand parts of water, by which dilution it forms a perfectly
colorless solution.
11
162
MANUAL OF CHEMICAL ANALYSTS.
The substance to be examined, therefore, after acidulation with
tartaric acid, and dilution, if necessary, with water, is subjected to
distillation in a flask or retort, provided with a condenser, and the
distillate collected in a receiver containing a little water (Fig. 72);
the distillation beirig continued until alwnt one quarter or one-
third of the liquid has distilled over. The distillate is then
examined by its odor, action iipitn litmus, and by the application
of the previously described reactions, viz., the formation of argen-
tic cyanide, Prussian blue, and ferric siilphocyanide. If a quaoii-
tfttive estimation of the acid is required, it may be converted into
^irgentic cyanide, by the addition of solution of argentic nitrate to
the distillate until a precipitate ceases to bo produced, and from
the argentic cyanide, dried at 100" C. {212° F.) until of constant
weight, the amount of pure hydrocyanic acid calculated; 100
Earts of argentic cyanide corresponding to 20.15 parts of absolute
ydrocyanic acid. As the distillate, however, may contain hvdro-
chloric acid in addition to hydrocyanic acid, the former should bo
tested for, and, when present, must be eliminated by the rectifica-
tion of the distillate over a little powdered borax or precipilaied
calcium carbonate, previous to its precipitation with argentic
nitrate; these substances serving to combine the free hydrochloric
acid, but are not acted upon by hydrocyanic acid, which ia thus
obtained in a pure form.
In view of the possibility of the occurrence of jiotassium ferro-
cyanide in the substant-e under examination, which would also
yield hydrocyanic acid by distillation with an acid, and of the fact
that it is It non-poisonous salt, the examination should be in-
variably precetlcd hy a test for ferrocyanides, by digesting a por-
ACIDA. 16S
tion of the substance with water, filtering the solution, and,
after acidulating with hydrochloric acid, applying the well-known
reaction with ferric chloride. For the separation of potassium
ferrocyanide when associated with hydrocyanic acid, or a soluble
simple cyanide, the organic materials, if not already possessing an
acid reaction, should be first slightly acidulated with sulphuric
acid, and then sufficient of a neutral solution of ferric chloride
added to precipitate the entire amount of ferrocyanide as Prus-
sian blue. After standing for some time the mixture is filtered,
and the filtrate, after the addition of a sufficient quantity of neu-
tral potassium tartrate to insure the complete combination of the
free sulphuric acid, is subjected to distillation. Bv operating in
this manner the distillate .can only contain hydrocyanic acid
when originally present as such, or in the form of potassium
cyanide.
ACIDUM H7P0PH0SPH0R08UM.
Hypophoiphoroui Acid,
Ger. Unterphosphorigesaure ; Fr. Acide hypophosphoreux ;
Sp. Acido hipofosf6rico.
/OH
H3PO, - 0=P^n : 66.
\h
A dense, syrupy, strongly acid liquid, which, at low tempera-
tures, forms large, colorless laminar crystals. The crystals melt
at 17.4^ C. (63.3° F.), and deliquesce gradually at ordinary tem-
peratures. By exposure to the air it becomes slowly oxidized to
phosphorous acid, and by the action of chlorine or nitric acid it
is converted into phosphoric acid.
Hypophosphorous acid in its aqueous solution possesses strongly
reducing properties, precipitating gold and silver from solutions
of their salts, and, when added to a solution of mercuric chloride,
either mercurous chloride or metallic mercury is separated, ac-
cording to the amount of acid present. When the acid, in excess,
is gently warmed with a few drops of solution of cupric sulphate,
at a temperature not exceeding 60^ C. (140^ F.), a reddish-brown
precipitate of cupric hydride. Cull, is produced ; with an excess
of the cupric solution, and upon more strongly heating, metallic
copper is separated.
The acid, when strongly heated, is decomposed into hydrogen
phosphide and phosphoric acid: 2H3PO, ■■ PH^ + HjPO^.
Ezamination :
Lead and Calcium Salts and Phosjjhoric Acid. — A small portion
of the acid is neutralized with ammonia-water, and is then tested,
in separate portions, as follows : A dark coloration or precipitate
164 MANUAL OF CHEMICAL ANALYSIS.
on the addition of ammonium sulphide will indicate lead, a white
precipitate on the addition of ammonium oxalate, calcium salts,
and a white precipitate with barium chloride, phosphoric acid.
IJydro(j€n stilphide may be recognized by a dark coloration on
the addition of a solution of plumbic acetate.
ACIDUM LACTICUM.
Lactic Acid. Oxy-propionic Acid.
Ger. Milchsanre ; Fr. Acide lactique ; Sp. Acido lactico.
C,H.O, - CH,-CH<g^^_Qjj ; 90.
A limi>id, odorless, syrupy liquid, colorless, or of a pale yellow-
ish tint, of a sour taste, and having the specific gravity 1.212 at
15^ C. (59^ F.), corresponding to 75 per cent, of absolute lactic acid.
It is iniscible, in all proj)ortions, with water, glycerin, alcohol, and
ether, and also, without being colored, with cold, concentrated
sulphuric acid. Lactic acid dissolves zinc and iron, with efferves-
cence, and cannot be distilled without undergoing partial decom-
j)osition. Heated upon platinum-foil, it emits inflammable vapors,
which burn with a pale flame, leaving a carbonaceous residue,
which is completely aissipated at a red heat. When heate<l with
a solution of potassium permanganate, lactic acid emits the odor
of aldehyde.
Examination :
Ovm, Mannite,iix\A Glucose. — A few drops of the acid are diluted
with water in a test-tube, and slightly supersaturated with sodium
carbonate ; to the clear liquid are added a few drops. of Fehling's
solution, and the whole gently warmed; a blue coagulation upon
the addition of the cupric solution before warming, would indi-
cate the presence of gum ; a brick-colored precipitate, after heating,
indicates glucose.
The presence of gum and mannite may also be recognized by
the occurrence of a turbidity upon dropping the acid into a mix-
ture of ecjual parts of alcohol and ether.
Glycerin may be detected by mixing, in a porcelain capsule, a
small portion of the acid with a slight excess of zinc oxide, pre-
viously triturated with a little water; the whole is then evaporated,
upon a water-bath, to dryness, the residue treated with strong
alcohol, and the obtained alcoholic soluticm evaporated upon a
watch-glass ; a neutral, syrupy, sweet residue would indicate
glycerin.
Sarcolactic acid may be detected by an ensuing blue precipitate,
when tested with a solution of cupric sulphate.
ACIDA. 165
Foreign Organic Acids. — Two drops of the lactic acid are added
Id a test-tube to so much lime-water that the alkaline reaction
predominates ; if a turbidity takes place at once, oxalic^ tartaric^
or phosphoric acids are indicated ; if the turbidit}' does not ensue
before the liquid is heated to boiling, citric acid is indicated. Acetic
and hxUyric acids are recognized by their respective odors when
the acid is gently heated in a porcelain capsule.
Sulphur iCy hydrochloric, and phosphoric acids may be detected in
the diluted aqueous solution of the acid by testing it, in separate
portions, with barium chloride for the former, and with argentic
nitrate for the two latter.
Acid calciuin phosphates or other calcium salts would be indi-
cated by a white turbidity of the dilute solution of the acid when
tested with ammonium oxalate.
Metals are detected in the acid, when neutralized with ammonia-
water, and then tested with hydrogen sul[)hide; awhile turbidity
or precipitate would indicate zmc, a brown or blackish coloration
or nrecipitate, copper, lead, or iron.
Estimation :
Ninety parts by weight of the officinal acid should be neutral-
ized by not less than seventy-five parts by weight of crystallized
f)oiassium bicarbonate, corresponding to 75 per cent, of absolute
actic acid. The acid may be also estimated volumetrically by
the process of neutralization, whereby 6 grams of the officinal
acid should require for exact neutralization 50 cubic centimeters
of a normal solution of potassium or sodium hydrate, which like-
wise corresponds to 75 per cent, of absolute acid. By the employ-
ment of other quantites of the acid than that above indicated, the
calculation may be made with the consideration that 1 cubic cen-
timeter of normal potassium or sodium hydrate corresponds to
0.09 gram of absolute lactic acid.
ACIDUM NITRICUM.
Nitric Acid,
Ger. Salpetersaure ; Fr .Acide nitrique ; Sp. Acido nitrico.
Nitric acid, in its most concentrated form, is a colorless, fuming,
corrosive liquid, having the spec. grav. of 1.580 at 15° C. (59°
F.). It begins to boil at 86° C. (186.8° F.), and becomes of a
dark-yellow color, due to the partial decomposition of the acid
into nitrogen tetroxide, oxygen, and water. When a strong acid
is subjected to distillation, it loses nitric acid, and the boiling
point is gradually increased until, at the temperature of 120.5° C.
(248.9° F.), an acid of constant composition distils over; a weak
acid, under the same conditions, loses water until, at 120.5° C
166 MANITAI. OF CUIiMICAL ANALYSIS.
(248.9° F.), the boiling point remains constant. This acid havini;
n oonstani boiling point has the B]tec. grav. of lAli at lo.o^' C.
(60° F.), and contains 68 per cent, of absolute nitric acid.
The crude commercial nitric acid is of two strengtha:, the so-
called double acid has a spec, grav. of 1,36, containing about 57
per cent, of absolute nitric acid ; and the single acid, of 1.22 spec,
grav., containing about 35 per cent, of absolute acid.
The officinal nitric acid has the spec, grav, of 1.420 (1,1.35
Pharm. Germ. =« 30 per cent. HNO,), and contains 69,4 per cent.
of absolute nitric acid. The Acidum Nitricum Diluturn, of 1.059
sf>ec. grav. (1.101 Brit. Pharm. = HJ.8 per cent, HNOj), contains
10 per cent, of absolute nitric acid.
Nitric acid is readily decomposed, and is a powerful oxidizing
agent, acting violently upon most of the metals, and upon organic
compounds, converting many non-nitrogenona vegetable sub-
stances into explosive bodies. From its tendency to decompose,
nitric acid has froquenlly a yellowish color from nitrogen oxides,
held in solution, which, 'upon dilution of the acid with water, or
upon heating, cause a further decomposition and consequent dis-
engagement of nitric peroxide. Nitric acid may be recognized
by its property of dissolving copper-turnings to a blue solution,
with the evolution of colorless nitric-oxide gas. which, however,
St once unites with atmospheric oxygen, forming red fumes of
nitric peroxide; by the ready decoloration of diluted solution of
indigo ; by its coloring pine-wood bright yellow ; and by deep red
or brown compounds with ferrous salts. An exceedingly delicate
lest for nitric acid depends upon its reaction with the alkaloid
briicine. A few drops of concentrated sulphuric acid, and one or
two drops of a saturated aqueous solution of brucine, are added to
the soluTion to be tested, when a fine rose or dark-red coloration
will be produced. By means of this reaction a solution containing
but one part of nitric acid in 100,000 parts of water will assume
a distinct pink coloration. Another excellent test, but somewhat
less delicate than the preceding, depends upon the reaction of
nitric acid with aniline. About 0,5 cubic centimeter (approxi-
mately 5 drops) of a solution of 10 drops of aniline in 50 cubic
centimeters of 15 per cent, sulphuric acid (Acid. Sulph. Dil., U. S.
P., may be employed) is brought into a small porcelain capsule,
and a glass rod, moistened with the liquid to be tested, is then
brought in contact with the liquid. If the nitric acid be verv
dilute, a rose-red coloration will be produced, but, ifGonocntrated,
tlie entire lii^uid will assume a brown or dark brownish-red tint.
The characteristic inaction of nitric acid with ferrous salts ex-
tends also to the nitrates, when previously acted upon by strong
sulphuric acid. The test is performed either by placing a cryst«l
of ferrous sulphate in the liquid under examination, mixed with
concentrated sulphuric acid, or by mixing the liquid with a con-
centrated solution of ferrous sulphate, and pouring this mixture
ACIDA. 167
carefully upon ooncentrated sulphuric acid in a test-tube, so as to
form in either case two layers (Fig. 73). If a large quantity of
nitric acid is present, the surfaces of the crystal, or the line of
contact between the liquids, become black ; if but a small quan-
tity is present, they become reddish -brown or purple.
Fig. 73.
Eumlnation :
Hydrochloric acid may be detected in the acid diluted with about
five times its volume of water, by the formation of a white preci-
pitate, when tested with argentic nitrate.
Sulphuric acid is detected in the acid, previously diluted with
at least five times its volume of water, by the production of a
white precipitate, either immediately or upon standing, on the
addition of a solution of barium nitrate.
Nitrous and hyponitric acids (nitrogen tetroxide) are detected in
the diluted acid, by the addition of one or two drops of a very
dilute (1 : 100) solution of potassium permanganate: their presence
is indicated by decoloration. They may also be recognized by add-
ing to the acia, previously diluted with about five times its volume
of water, a few drops of a solution of potassium iodide, and a little
mucilage of starch, when a blue coloration will be produced.
Iodine and Iodic Acid. — A small portion of the acid (the con-
centrated acid should be diluted with about five times its volume
of water) is shaken, in a test-tube, with a few drops of chloro-
form, which, after subsiding, will appear of a reddish- violet color
if free iodine be contained in the acid ; when it remains colorless,
or after the removal of the free iodine, if present, by agitation
with chloroform, a very small quantity of an aqueous solution of
hydrogen sulphide or sulphurous acid is added, drop by drop.
l(!8
HANllAL OF CHEMICAL ,
wiihgoutlo agitation: if a c<i!orntioiiof tlie chloroform now takes
|lla^^c, ioJic add ia indicated.
A coiillrmalory test is, to tnix the acid, after dilution, if strong
auid iri under examination, with a few drops of mucilage of starch;
a bliiiiih culuration will take place after a while, when iodine is
(iraaent: if no reaction occurs, a few drops of solution of aulpiiur-
uUB acid may be added, diop by drop, wlien the blue color will
ujijiuur. if iodic acid be present.
Mflalu may be detected by saturating the diluted ncid with
liydrogon Muiuliide, wlien an ensuing dark coloration or prccipi-
talii will indiciite Uad or copper; the liquid is then filtered, if
nouniMiiry, nnil supersaturated with ammonia- water; if a dark
iHiloratiim i« now produced, it will indicate iron,
Artenic, in the form of arsenic acid, is detected by neutralizing
H portion of the acid with solution nf potassium hydrat«, subse-
quently adding twice its volume of a strong solution
V\a. 74. of potassium hydrate and a few fragments of pare
zinc, and heating the mislnre in a test-tube, provided
with a cap of bibulous paper moistened with a drop of
solution of argentic nitrate (Fig. 74); the production
of a black stain upon the paper will reveal the pres-
ence of arsenic.
EBUmation :
Tbe estimation of nitric acid is most conveniently ac-
complished volumetriually by the process of neutraJiza-
lion. About 5 grams of the acid, accurately weighed
iu a beaker, are diluted with about 60 cubic centime-
ters of water, a few drops of litmus solution added, and
it normal solution of potassium or sodium hydrate
(page 87) allowed to flow into the liquid from a burette
until, with constant stirring, the liquid assumes a per-
manent blue tint. One cubic centimeter of the normal
alkali solution corresponding to 0.068 gram HNO„
the amount of absolute acid in the quantity employen,
and its percentage strength, may readily he calculated.
In addition thereto the specitic gravity of the acid may-
be determined, and the result of the volumetric estima-
tion compared with the percentage strength of an acid
having a corresponding specific gravity, as indicated
by the subjoined table, page 170.
Of the strong ofBcinai acid 4.5-1 grams, and of the
diluted acid 31.5 grama, are neutralized by 50 cubic centimeters
of normal solution of potassium or sodium hydrate.
ACIDA. 169
Rules for the Dilution of Nitric Acid.
If a strong acid, a, has to be diluted with water, or with a
weaker acid, c, in order to obtain an acid of some special strength,
J, the following rules are applicable :
The difference in percentage strength is sought, on the one
hand, between a and i, and, on the other, between b and r, and a and
c are then mixed in the proportions represented by the difterence
in the respective numbers. It must be observed, however, that
when the difterence between a and b is greater than between b
and c, less of a than of c must be taken in order to obtain b; and
when the difterence between a and b is less than between b and c,
more of a than of c must be employed in order to obtain b; for
example :
I. Nitric acid, containing 29 per cent, of absolute acid, is to be
mixed with water, to form an acid containing 25 per cent, of
absolute acid :
a, b, c.
29 per cent. 25 per cent. 0 per cent.
Difference 4 25
25 parts of 29 per cent, acid are, therefore, to be mixed with 4
parts of water, or
100 grams of nitric acid =» 29 grams HNO3
16 " " water «
116 grams of nitric acid «■ 29 grams HNO3
or 100 " " " " — 25 " ''
II. Nitric acid, containing 32 per cent, of absolute acid, is to
be mixed with an 8 per cent, acid, to form an acid containing 14
per cent, of absolute acid :
rt. b. c,
32 per cent. 14 per cent. 8 per cent.
Difference 18 6
(3) (1)
1 part of 32 per cent, acid is, therefore, to be mixed with 3 parts
of 8 per cent, acid, or
100 grams of nitric acid — 32 grams NHO3
300 " " " " — 24 " "
400 grams of nitric acid — 56 grams HNO,
or 100 " " " " « 14 " "
NUAL OF CHEMICAL ANALYSIS,
Tabi:S of tht qnoHlity hy weight of ahtolnte Nilrin Acid, nnd thf for-
retponding equivalent of Nitric Anhydride, eontatnid in 100 partt by
meighl of Nilrie Acid, of different tpeeifie gravitiet.
Temperatnre 15° C. (590 p,).
fip.<<lB
Far «Bt.
Par cl.
SpeelOo
P.yt,
P"Vf"'-
SpHllo
rmtU
ParMBI.
ft.Tllj.
BKO,
«°o..
««.!.)'.
H.1t.„
Vfi,.
.-.TllJ.
hSIs-
^%
1.530
100.00
85.71
1.483
73.00
83.57
1,208
47,18
40-44
I. MO
99.84
85.57
1.433
73-38
63.05
1.305
46,64
30.07
1.530
89.73
85.47
1.439
71.34
81.06
1,284
4.5.00
38,57
l.ri2fl
69.32
85.S0
1.428
89.06
80.00
1.374
43 53
37.31
1.528
07.89
83 00
1.418
80-30
59.31
1,364
43.00
80.00
i..^ao
97 00
8.3.14
1-414
68.00
58,39
1,3.17
41.00
3.5.14
l.,t16
96.00
83.38
1,410
67.00
57.43
1.351
40.00
34.26
I.5H
95.37
81. H6
1,405
6a,oo
58. .17
1,844
30.00
33.48
I. SOB
94.00
80.57
1.400
6.1,07
55.77
1.387
37.0.1
32.53
1.506
83,01
78.73
1.893
04,00
54.85
1.825
36.00
30.89
1,508
BS-OO
78,8.1
I. HI'S
63,. 10
64.50
1.818
35.00
39.39
1.4110
81.00
78 00
1.398
63.00
.13.14
1-311
3380
30.03
i.4n,i
90.no
77.15
1.381
61.31
53.48
1.188
33.00
37.48
1.404
8H.50
76.77
1,374
60.00
f.1.43
1,103
81.00
86..57
1.488
88.(10
7-1.48
1.373
50.50
51.08
1,185
30.00
35.71
1.488
87,4.1
74.05
1.368
58,86
50,47
1,178
30.00
84.ftl
1,483
86.17
73,86
1.863
58.00
40.71
1.173
2fl(»0
24.00
1477
85.00
73.80
1.858
r,lM
48.66
1,136
27 00
28. 14
1.474
84.00
73.00
IS53
66 10
48.06
1.1.17
S5.71
23.04
1.470
83.00
71.14
1 34S
55-00
47.14
1.138
33 00
18.71
1.4fl7
83.00
70.38
1.B41
S4.00
48 20
1.130
20.00
17.14
].4«3
80.86
60 30
1.839
58.81
40.13
1.105
17.47
14.97
i.4ao
80 00
68,57
53,00
45,40
1,080
15.00
13.85
1.4.18
70.00
67,71
1.831
53,33
44.85
1.077
18.00
11.14
1.451
77,00
66.56
1.333
50.08
43-70
1.067
11.41
9.77
1.445
78.00
6-1.14
1.817
40 07
43,8;t
1.045
7.33
6.88
1.443
75.00
61,28
1.812
40.00
43 00
1038
4.00
3.48
1.438
74,01
ea,44
1.304
43-00
41.14
1.010
3.00
I.Tl
Wllh Ihe dccreaso and increase of temperaliire, tlie speciGc gravity of nflric
Mcid auQrrB a cnrrespoDdlng increase or decrease, amounting for eacU degree ol
the centigrade thermi)nieler Id eitlier direction :
Foracids of a gpeclBc gravity uf 1.404 lotbnse of 1.477 lo 0.00213 in Ibeavernge-
LVor iattiirica: An add of 1.170 spec. ^
cent, of nitric aniiydride, or 30-00 of nlisnl
\ spec. grsT. of 1.179 — (0.00071 X 3.5) = 1.1773. and at. 13^0. a apec. gniv.
nf 1.179+ (0.00071 X3)=> 1.1804.
1.474
1.4.16
'0.003
1.4.10 *
1.485
' 0,00186
1.438
1.410
•0,00171
1.405
1.881
'D. 001 55
1.874
1.3.13
' 0,00141
1.846
1.817
' 0.00188
1.304 ■
1.374
'0,00114
1.274 '
1.287
' 0,001
1.337
1.198
• 0,00085
1.183 '
1.168
'0 00071
1.1-57
1.120
•0.OO05
AGIDA. 171
ACIDUM OLEICUM.
ACIDUM OLEINICUM.
Oleic Aeid.
»
Ger. Oelsaure ; Fr. Acide oleique ; Sp. Acido oleico.
C^Hj^O, = C.,H33-CO-OH ; 282.
An oily liquid, without odor or taste, and colorless or having
but a slight yellow color. It solidifies at 4° C. (39° F.) to a com-
pact, white crystalline mass, and from its solution in alcohol it
crystallizes in brilliant white needles, which melt at 14° C. (57°
F.) to a colorless oil. Its specific gravity is 0.808 at 19° C. (66°
F.). When perfectly pure, and unoxidized, it is neutral in its
action upon litmus, but on exposure to the air, especially when
slightly impure, it rapidly absorbs oxygen, acquiring thereby a
yellow or brownish -yellow color, a rancid taste and smell, and an
acid reaction. When strongly heated, it becomes decomposed, but
with super-heated steam it may be distilled unchanged at 250^ C.
(482° F.). By treatment with nitrous acid, oleic acid is converted
into the solid isomeric elaidic acid, which crystallizes in laminae,
melting at 44 to 45^ C. (Ill to 113^ F.). Oleic acid is insoluble
in water, but freely soluble in alcohol, ether, chloroform, benzol,
petroleum benzin, and the volatile and fatty oils ; it is also soluble
in cold, concentrated sulphuric acid without decomposition.
Exambiation :
Stearic and palmitic acids will be indicated by a higher con-
gealing point than 4® C. (39° F.), and may be also detected by
the following test : A portion of the acid is completely saponified
by potassium carbonate, with the aid of a gentle heat, the result-
ing soap dissolved in water, exactly neutralized with acetic acid,
and the solution precipitated with plumbic acetate; the ensuing
precipitate of plumbic oleate, after being twice washed with boil-
ing water, should be completely or almost completely soluble in
ether; any considerable insoluble residue will indicate an undue
proportion of an admixture of stearic or palmitic acids.
Fixed oils, with the exception of ricinus or castor oil, may be
detected by the formation of a turbid mixture. or the separation
of oily drops, when the acid is mixed with an equal volume of
strong alcohol, and heated to 25^ C. (77° F.).
Lead may be detected by a brown or blackish coloration or
precipitate when the alcoholic solution of the acid is saturated
with hydrogen sulphide.
This hook is the propc . ^
COOPER MEDICAL COLL.-o -.
SAN FRANCISCO. OAL.
• oprl iff i^ot to he remo'^'d /»»m ^^'^
/'
MANUAL OF CllBM
ACIDUM OZAI.ICUM.
Oer. Oittlsiure ; Fr. AdJo nsniiqan ; Sp. Acida ot&llco.
CO-OH
C,H,0, + 2U.0 - I + 2H,0; 126.
CO-OH
Colorless, transparent, oblique-rliombiu prisms (Fig. 75), con-
taining two molecules (28 per cent.) of water of crystallization,
which they lose gradually upon exposure in a warm and dry
atmaiphere, orqnickly upon heating at
F"""- 75. 100° C. (212° F.), becoming reduced to
n soft while powder. By cautiously
heating at a temperature not exceeding
150° C. (302° F.), the anliydroua acid
may be completely sublimed; exposed
to a strong neat it develops irritating
inflamable vapors, and is resolved,
without carbonization, into carbon di-
oxide, carbon monoxide, formic acid, and water, and is iinally
completely dissipated.
O.talic acid is soluble in 14 parts of water at 15° C. (59° F.),
and in its own weight or leas of boiling water, in 6 to 7 parts of
90 per cent,, and 4 parts of absolute, alcohol ; it is also soluble in
7 parts of glycerin, but sparingly soluble in ether and chJoroform.
Its solution has a very sour taste, and a strong acid reaction j it
forms with the alkali metals soluble, with all other bases, for the
most part, insoluble, salts, which, however, are soluble in dilute
mineral acids.
When a cold saturated aqueous solution of oxalic acid is
dropped into strong alcohol, it shimld not produce a turbidity;
when dropped into lime-water, a copious white precipitate must
ensue at once, which remains unchanged upon the addition of
acetic acid, as well aa of ammonium chloride, but which is readily
dissolved by hydnwhloric and nitric acids. Added to a solution
of calcium sulphate, a precipitate is also produced after a while.
When heated with concentrated sulphuric acid, oxalic acid is
resolved into water and equal volumes of carbon monoxide and
carbon dioxide gases, without being charred.
Examinatioa ;
Bhoxahtes and quadroxalates of potassium (sorrel and lemon
salts) are detected by heating a small portion of the oxalic acid in
a platinum or porcelain capsule, to redness, and until no more
fumes are emitted; a white fused residue, turning red litmus-
paper blue, and eServescing with a few drops of hydrochloric
acid, would indicate potas-tium or traces of calcium,
The crude commercial acid mostly leaves a very small trace of
ACIDA. 173
residue, too insignificant, however, to impair the quality of the
acid, or to render it unfit for its common technical applications.
Tartaric^ citric^ and racemic acids^ and their salts, as accidental
admixtures in oxalic acid, may be detected by gently heating a
small quantity of the acid on platinum-foil, when they will be
recognized by the development of a peculiar caramel-like odor,
and a voluminous carbonaceous residue ; when heated, in a test-
tube, with concentrated sulphuric acid, the crystals, as well as
the sulphuric acid, must not become dark-colored or blackened,
otherwise the presence of one or the other of such admixtures is
indicated.
The acid should dissolve perfectly in water, forming a clear
solution, and, when saturated with hydrogen sulphide, should
aflPord no coloration or precipitate.
Estimation :
Oxalic acid may be estimated volu metrically, either by the
process of neutralization with a normal alkali, or by oxidation in
its warm aqueous solution, slightly acidulated with sulphuric acid,
with a standard or decinormal solution of potassium permanga-
nate; it being resolved by the latter, through absorption of oxygen,
into carbon dioxide and water.
I. Three grams of the air-dry, but uneffloresced, acid are dis-
solved in about 50 cubic centimeters of water, and, afterthe addition
of a few drops of litmus solution, a normal solution of potassium
or sodium hydrate (page 87) is allowed to flow into the liquid
from a burette until, with constant stirring, a permanent blue
coloration is produced. Oxalic acid being dibasic, each cubic
centimeter of alkali solution employed, corrected if necessary by
its proper factor, corresponds to 0.063 gram of crystallized acia,
from which the percentage amount of pure acid in the specimen
under examination may be readily determined.
II. 0.2 gram of the crystallized acid are dissolved in about 200
cubic centimeters of water, in a beaker, 5 to 10 grams of dilute
sulphuric acid are then added, and, after gently heating, a standard
solution of potassium permanganate (page 89) is allowed to flow
into the liquid from a burette until, with constant stirring, a
j)ermanent pink coloration is produced.
The reaction may be expressed as follows : CjH,0^ + O —
2CO, + H,0. One atom of oxygen thus oxidizes one molecule
of oxalic acid, and the same amount of oxygen would oxidize
two atoms of iron from the ferrous to the ferric state : 2FeS0^ -f
H^O^ + O » Fe,(S0Jj + H,0. From these deductions one mole-
cule of oxalic acid corresponds to two atoms (one molecule) of
iron ; and placing then the molecular weight of iron (112) as the
first term, the molecular weight of crystallized oxalic acid (126)
as the second term, and the amount of metallic iron, expressed in
grams, corresponding to the number of cubic centimeters of per-
MANUAL OF CHEMICAL ,
i
mangaiiate solution employed, as tlie third term, a siinple ppo-
ptirtioa will determine the amount of pure crystallized oxalic arid
contained iu the epecimen under examination.
ACIDtTU PH08FHORICTTM.
■e ; Fr, Acidi' pliospborique ; Sp. Aeklo fosffirico.
Metapboaphoric Acid, HPO, - 0=P<^qjj; 80.
Ortliophosphoric Acid, H,PO, - 0-Pf OH ; 98.
Monoltaeic or metaphoaphoric add, HPOj, when perfectly pnre,
forms a soft pasty mass, which, on exposure to the air, readily
absorbs moisture, and deliquesces to a thick syrupy liquid. The
t)lucial phoaplwrtc add (Acidum Phosphoricum Glaciale) is an
impure metaphoeplioric acid, containing frequently considerable
amounts of sodium or calcium phosphates, and lorms colorless,
transparent, glass-like, fusible masses, deliquescent, and slowly
but freely soluble in water and in alcohol, yielding colorless, ino-
dorous, acid solutions. The aqueous solution of metAphosphorio
acid, when freshly prepared, produces white precipitates with
albumen and with solutions ot argentic nitrate and barium and
calcium chlorides, which are soluble in an excess of the acid, while
free orthophosphoric acid precipitates none of the above men-
tioned reagents. When its solntion is allowed to stand for some
time, or by continued boiling, the monobasic acid is converted
into the tnbasic acid, which is contained in the medicinal Acidum
Phosphoricum Dllutum. This process is accelerated by the ad-
dition of a little nitric acid to the boiling solution of the mono-
basic acid.
Tribntic or ortkophoaphnric add, HjPO,, when free from water,
forms an odorless and colorlysB, dense, syrupy liquid, possessing
a strongly acid taste and reaction. On standing over sulphuriu
acid, or by exposure to cold, it crystallizes, forming six-sided
prisms, terminated by six-sided pyramitis, belonging to the
rhombic system, which melt at 38.)}^ C. (101.6^ F.}, and readily
become liquefied in the presence of a small amount of water.
The specific gravity of the anhydrous acid is 1.8S at 15" C. (oB**
F.). At temperatures above 160" C. (320" ¥.) it loses water, and
at 213" C. (415.4" F.) it is completely converted into pyrophos-
phorio acid, Il^P^O, ; when healed to redness, the latter acid
becomes in turn further decomposed, losing water, and metaphos-
pborio acid, HPO„ is produced.
ACIDA. 175
Orthophosphoric acid, as previously stated, when in the free
state, does not precipitate albumen, nor a solution of argentic
nitrate or barium chloride ; when carefully neutralized by ammo-
nia-water, however, it yields a white precipitate with a solu-
tion of barium chloride, soluble in nitric or hydrochloric acids;
with argentic nitrate a yellow precipitate of argentic phosphate,
soluble in nitric acid or ammonia- water, and with test magnesium
mixture, a white crystalline precipitate of ammonio-magnesium
phosphate. When heated with a solution of ammonium molyb-
date, acidulated with nitric acid, a yellow crystalline precipitate
of ammonium phosphomolybdate is produced.
Two strengtns of orthophosphoric acid are officinal:* Acidum
Phosphoricum, containing 50 per cent, of absolute acid, and having
a specific gravity of 1.847; and Acidum Phosphoricum Dilutum,
containing 10 per cent, of absolute acid, and having a specific
gravity of 1.057.
Examination of Metaphosphorio Aoid :
AmTnonhim salts may be detected by heating a few fragments
of the fused acid in a strong solution of potassium hydrate in a
test-tube, wl^en they will be recognized by the odor of ammonia,
as also by the production of white fumes, when a glass rod, moist-
ened with acetic acid, is held over the orifice of the tube.
Calcium^ magnesium^ and aluminium salts may be detected by
dissolving a small portion of the acid in water, boiling with a few
drops of nitric acid, and, after the removal of the excess of nitric
acid, carefully neutralizing with ammonia-water, when the phos-
f hates of calcium, magnesium, and aluminium will be precipitated,
f a precipitate is thus obtained, it is separated by filtration, the
filtrate reserved for subsequent examination for sodium or potas-
sium salts, and the precipitate further examined as follows : It is
first digested with a concentrated solution of potassium or sodium
hydrate, the solution filtered, and to the filtrate solution of ammo-
nium chloride added, when a transparent, flocculent precipitate
will indicate aluminium. The portion of the precipitate insoluble
in the alkaline hydrate is then dissolved in hydrochloric acid, an
excess of a solution of sodium acetate, and subsequently a little
ferric chloride added, until the liquid assumes a yellowish hue,
heated to bbiling, and filtered ; to a portion of the l^ltrate solution
of ammonium oxalate is added, when a white precipitate will indi-
cate calcium; to another portion of the filtrate ammonium carbo-
nate in slight excess is added, the solution filtered, and to the fil-
trate ammonium phosphate and ammonia-water then added, when
a white crystalline precipitate will indicate magnesium,
♦ The pbospboric acid of the Pharmacopcpia Germanica has a specific gravity
of 1.120, corresponding to 20 per cent, of absolute acid ; and the diluted phos-
phoric acid of the Britisli Pharmacopoeia a specific gravity of 1.08, corresponding
to 14 per cent, of absolute acid.
176
MANUAL OF CHEMICAL ANALTSia.
Sodium or potassium salts may be detected in tbe filtrate from
the precipitate produced by ammonia- water, as above described,
by tiie following method: The phosphoric acid is first completely
precipitated by neutral plumbic acetate, the filtrate freed from
lead by hydrogen sulphide, filtered, and the filtrate evaporated
atid ignited. If a residue is thus obtained, it will contain the
sodium or potassium salts in the form of carbonates, and Diay be
further examined or identified by the color imparted to the non-
luminous flame, when tested on platinum wire.
Silicic acid may be detected by evaporating a portion of the
flolution of the acid, to which a small quantity of hydrochloric
acid has been added, to drynesK, with the aid of a gentle heat; the
residue is then dissolved in water, slightly acidulated with hydro-
chloric acid, when the silicic acid, if present, will remain behind
an an insoluble granular powder.
MtlaUic and othtr impurities may be detected by the methods
described under orthophosphorie acid.
Ezamlnation of Orthophoaphorio Aoid:
Monobasic or melaphosphoric acid may be detected by a white
pitate on Ibe addition of a solution of barium chloride, and
ly the formation of a gelatinous white precipitate when tested
with solution of albumen.
Phosphorous acid may bo detected in the diluted acid by the
addition of a few drops of a solution of argentic nitrate or mer-
t
curie chloride, and geiilly warming; a brown or blackish colora-
tion or precipitate with the first reagent, and a grayish -colored
precipitate with the latter, will indicate phosphorous aoid. A
dilute solution of the acid, to which one or two drops of a solutioii
ACIDA. 177"
of potsKSJnm permanganate is added, will also become readily
decolorized oit wanning, if phosphorous acid is present.
Hydrochloric acid is detected in the diluted acid, to which a few
drops of concentrated nitric acid have been added, by a white
precipitate on the addition of a solution of argentic nitrate.
Nitric acid is indicated by ensuing decoloration when a little of
the acid is gently heated with one drop of indigo-solution. Its
presence may be confirmed by mixing with the acid nearly an
equal bulk of concentrated solution of ferrous sulphate, and
placing this mixture upon concentrated sulphuric acid, with the
precaution that the two fluids do not mix (Fig. 76}; a red-brown
coloration upon the line of contact between the two fluids will'
confirm the presence of nitric acid,
Sulphuric acid is delected in the diluted acid, to which a few
drops of nitric acid have been added, by a white precipitate with
barium nitrate,
Melah are detected by saturating the diluted acid with hydrogen
sulphide, and allowing the liquid to stand for 12 hours in a corked
test-tube or flask; the occurrence of a coloration or precipitate
will indicate metals;* a light- yellow, flocculeut one, arsenic; a
brown or black one, copper or lead.
Arsenious as well as arsenic acid, besides having been Fia. 77,
detected in the test for metals with hydrogen sulphide,
may be apeoially tested for by the application of Marsh's
test, as described on pages 33 to 35, or by the follow-
ing modification of the same. To a small quantity
of the dilute phosphoric acid, contained in a test-tube,
one drop of solution of [Mtassium permanganate is
added, and the liquid gently warmed; if decoloration
takes place, the addition of solution of permanganate
is oontinned, drop by drop, until decoloration of the
reagent ceases; dilute sulphuric acid and fragments of
pure zinc (both of which should have been previously
tested for arsenic) are then added, not allowing the
liquid to occupy more than one-fourth of the capacity
of the lube, A small cap of bibulous paper, previously ^^H'tl
moistened with a drop of solution of argentic nitrate, is
then placed over the mouth of the tube (t'ig, 77), and
the reaction accelerated, if necessary, by gently warm-
ing; the production of a purplish-black spot on the
paper, due to the reduction of metallic silver, will con-
firm the presence of arsenic.
The strength of officinal phosphoric acid may be ap-
proximately determined by ascertaining its specific
178
MANUAL OF CHEMICAL ANALYSIS.
gravity, and subsequent reference to tlje subjoined table (pl^
180), Unlike moat other acids, it cannot be estiiiiiited by direct
neulraiization witb an alkali, since the point of neutralization,
as indicated by meaus of litmus, cannot be disliuotly observed,
and in connection therewith is the fact of its forming three classes
of salts — NaHjPOj, which has an acid reaction, and Na,HPO^and
Na,PO,, both of which possess an alkaline reaction.
Among the various methods employed for the quantitative
estimation of the olBcinal or orthopliosphorio acid, the two fol-
lowing will be found expedient and sufficiently accurate.
I. Volumetric. — This method depends upon its indirect estima-
tion by the process of neutralization, A convenient quantity of
the acid (about 10 grams of the officinal diluted acid, or 2 grams
of the stronger acid) is accurately weighed, in a beaker, a normal
solution of potassium or sodium hydrate (page 87) ihen allowed
to flow in from a burette, until sufficient of the latter has been
employed to insure the formation of the neutral sodium salt,
Na,PO^. To the strongly alkaline liquid a solution of bartum
chloride is then added until no further precipitate is produced, the
resulting barium phosphate Ba,{POJ,, after being allowed to
stand for a few hours, filtered olV, the precipitate well washed
with water, and the filtrate together witli the washings collected
in a beaker; after the addition of a few drops of litmus solution,
a normal solution of oxalic or sulphuric acid (page 82) is allowed
to flow into the liquid from a burette until, with constant stirring, a
permanent pink tint is produced. The number of cubic centimeters
of normal acid solution required, deducted from the number of cubic
centimeters of alkali solution first employed, will give the amount
of the latter required for the exact neutralization of the phos-
phoric acid; one cubic centimeter of the normal alkali corre-
sponding to 0.0327 gram HjPO^ the percentage strength of the
acid may be readily calculated.
II. Oravinietrir.—Ahoul 10 graniB of the officinal diluted acid,
or about 2 grams of the stronger acid, are accurately weighed, in
a beakor, ammonia-water, in slight excess, then added, and subse-
quently test magnesium mixture, until, after having been well
stirred and allowed to stand for a short time, no further precipi-
tate is produced on the addition of the reagent. Ammonia-water,
in an amount equal to about one-fourth of the volume of the liquid
contained in the beaker, is then added, and the latter being covered,
it is allowed to stand for about twelve hours. The precipitate of
ammonio-magnesium phosphate is then collected on a filter, washed
with a solution consisting of 1 part of ammonia-water and 8 parts
of water until the washings no longer produce a turbidity in a
solution of argentic nitrate acidulated with nitric acid, dried at
100° C. (212'^ F.), and finally ignited in a weighed porcelain cru-
cible at a low, red heat. From the weight of the resulting mag-
nesium pyrophosphate, Mg,PjO„ the amount of phosphoric aoid
ACIDA. 179
contained in the solution, or the percentage strength of the same,
is readily calculated : 100 parts of magnesium pyrophosphate cor-
responding to 88.39 parts of phosphoric acia, HjPO^, or 64.28
parts of phosphoric anhydride, PjO,.
The U. S. Pharmacopa3ia directs that on pouring 5 grams of the
stronger acid upon 10 grams of plumbic oxide free from plumbic
carbonate and from moisture, evaporating and igniting, the obtained
residue should weigh 11.81 grams ; and that 5 grams of the diluted
acid with 5 grams of plumbic oxide, under the same conditions,
should yield a residue weighing d.S6 grams.
Rules for the Dilution of Phosphoric Acid.
If a strong acid, a, has to be diluted with water, or with a
weaker acid, c, in order to obtain an acid of some special strength,
/y, the following rules are applicable:
The difference in percentage strength is sought on the one hand
between a and h, and, on the other, between b and c, and a and c
are then mixed in the ]>roportions represented by the difterence
in the respective numbers.
It must be considered, however, that when the difference between
a and b is greater than between b and c, less of a than of c must
l>e taken in order to obtain b; and when the difterence between a
and b is less than between b and <:, more of a than of c must be
employed in order to obtain b; for example :
I. Phosphoric acid, containing 45 per cent, of absolute acid, is
to be mixed with water, to form an acid containing 10 j^er cent,
of absolute acid :
a. b. c,
45 per cent. 10 per cent. 0 per cent.
Difference 35 10
10 parts of 45 per cent, acid arc therefore to be mixed with 35
parts of water, or
100 grams of phosphoric acid «= 45 grams HjPO^
350 ** '' water =
450 grams of phosphoric acid = 45 grams H3PO^
or 100 " " " " = 10 " "
II. Phosphoric acid, containing 32 per cent, of absolute acid,
is to be mixed with an 8 ])er cent, acid, to form an acid containing
10 per cent, of absolute acid :
a. h, c.
32 per cent. 10 per cent. 8 per cent.
Difference 22 2
(11) (1)
IRO
ABCAL OP CaBMICAL AN
1 part of 82 ^>er cent, acid ia therefore to be mixed with 11 }
of 8 i<er <^nt. acid, or
100 grams of phosphoric acid — 32 grams HjPO,.
1100 " " " " =88 ■■
1200 grama of phosphoric acid ■* 120 grams H^O,.
100 = 10 "
Tabi.R o/ Ihe qnanlUy hy weight of Orlhoph/ttphorir Arid, and the cor-
rrtponding amiiiuit i>f Pliotphoric Anhydride, contaiued in IIIO part*
by toeifht of a^ueput Phoiphorte Acid t/f different tpeei^e grarities
(Schiff).
Temperature ISO c. (G»o P.).
apectt.
^'ir-
F.rr»..!
Bi>"il<^
P..et.
PHfM. '
Spcdlc
P»r«.
r.,.«i.
«»««».
np-o,-
Pt".
^..11,.
H.PO,.
Pto..
(fmll.r.
H-ro,
^'k
l.OOH
,
0,72« '
i.iaaa
81
15.348
1.2781
41
89.766
1.0109
a
1.4^2
1.1329
23
15.973
1.3813
42
80.493
1 0104
s
2.178
1.1397
33
10 898
1.8S94
43
31.318
1.<R20
4
2.WU
1.146-^
34
n.424
1.2076
44
81.944
1.0370
5
3.030
1.1534
3:.
18.150
l.S05»
45
82,670
1.0883
0
4!t.'>fi
1.1604
20
18.876
1.8143
46
33.498
t.onw
7
B.oe2
1.1674
27
19 603
1-3337
47
84.233
I.044D
8
5.80*.
1.1745
as
20.838
1 3318
48
34.B48
1.06(18
9
0,^84
1.1817
29
21.054
1.8390
40
85.674
I.0M7
10
7.260
1.I88S
30
31.780
1.3486
50
80.400
1.0827
11
T.nsfl
1.1^102
81
23.506
1,3573
51
87.126
,1.0«88
13
8. 71 a
1.2086
33
28.333
1.3681
52
37-859
1.0749
13
0.438
1.2111
33
33.B58
1.37.W
53
38 5711
1.0811
14
10.164
1.S186
34
34.664
1.8840
54
89.304
1,0874
L-S
10.890
1.2262
•Ah
25.410
1.3981
55
40.080
1.0987
16
ii.eie
1.2338
SO
3fi.l3B
1.4023
58
40.7.'i6
1.1001
17
12.843
, 1.3416
37
36.803
1.4114
57
41.483
1.106S
18
la.ofls
I.S4S8
38
37.588
1.4307
5S
43.308
1.1180
19
18.794
1.2573
»»
28.314
1.4301
59
43.934
l.UBA
20
i4.:>ao
i.a«5i
40
29.040
1.43D5
00
48,000
With the dpcrpnse or increBse of lemperalure, tlie spociSc g™**'? "f ph"a-
pbnric scid suRers a correspopdlng iocreagc or decrease, amounting for each
dcgrpe of llie ceotigrade lliemKimeler in cillier direcliiin :
ForftcidsofBtpeciacgrnvily of 1.05G7 lo iliose of 1.1198 to abuui 0.00035
■' 1.1383 ■■ I.ISSK •• 0.OOO40
" " " 1.1983 ■■ 1.3651 '■ 0.000,53
1.2731 " 1.8480 " 0.00068
" " •■ 1.3573 " 1.4395 '■ 0.00082
For intlanea : hti Rcld of 1.1263 oprc. grux. at 15° C, cnntnininfr 10.340
percent of phoephoric aDliydridv or 31 per cf nt. of pliORplioric nciil, will liave
at JOG C. » spec. grev. of 1.1268 — (0.0004 x 5; = 1.1342, nnd al 180 C. a
spec. gnr. of 1.1363 + (0.0004 x 3)= 1.137.
^
FiQ. 78.
ACIDTTM SAIiICTI.ICtJM.
Satif^lie Acid, Orlho-orgbeazoic Add.
Ger. Salicjluara; Fr. Acide Ballnylique ; Sp. Aclda Mlicilioo.
O.H.O.-C.n,<;','0_ojj;138.
Fine, light, colorless needles, or four-sided prisms (Fig. 78),
otlorleas, or having but a slight aromatic odur, and permanent in
the air. They fu-fe at 156" C. {312.8" F.). and when carefully
heated may be aublimed without decomposition;
when quickly or more atrongly heated, they are
resolved into carbon ditixide and phenol, a de-
composition which takes place to a slight extent
when aqueous solutions uf the acid are boiled ;
wlicn slrougly heiiled on platinum-foil they are
completely dia.«ipateii.
Siiiicylic acid is soluble in 450 parts of water,
and in 2.6jians ofaleoboi at 15° C. (oi)° F.); in
14 parts of boiling water, and very freely in boil-
ing alcohol; in 2 parts of ether or absolute alco-
hol, in 3..') parts of amylie alcohol, and in yO
parts of chloroform ; and sparingly soluble in
benzol, carbon bisulphide, glycerin, and the vol-
atile and fatty oils; it is readily soluble in solu-
tions of the alkaline hydrates, forming crystal-
lizable salta; and is also soluble in cold, concen-
trated sulphuric acid, without coloration, being precipitated from
the latter solution unchanged on the addition of wjiter. The
solubility of the acid in water ia greatly increased by the presence
of various salts, such as the alkaline carbonates and acetates,
borax, etc., which form with the acid readily soluble compounds.
The aqueous solution of the acid has an agreeable, somewhat
sweetish taste, and an acid reaction, and assumes with a trace of
ferric chloride an intense violet color ; this reaction, however, ia
modilied by the presence of alkaline hydrates, carbonates, acetates,
and phosphates, as also by borax, potassium iodide, oxalic, citric,
tartaric, phosphoric, and arsenic acids. With bromine-water the
aqueous solution yields a white precipitate of bromo-salicylic
Bciil, CjH,BrOj. Tf to an aqueous solution of salicylic acid, or pre-
ferably a perfectly neutral solution of its sodium salt, a solution
of cupric sulphate be added, a bright emerald-green color is pro-
duced, but wnich is destroyed by the presence of free alkalies or
acids,
lExainiDatloD:
Fij:e'l inij/w-ici'^s may be recognized by a non-volatile residue
when a small portion of the acid is atrongly heated on platinutn-
foil.
182 MANUAL OF CHEMICAL ANALYSIS.
Orfjanic admixtures may be detected by the separation of car-
bon when a little of the acid is heated on platinum-foil, or in a
dry test-tube; or by a dark coloration when a small portion of
the acid is agitated with about fifteen times its weight of cold,
concentrated sulphuric acid.
Chlorides or hydrochloric acid may he detected by an ensuing
white precipitate when a little of the acid, dissolved in about ten
times its weight of alcohol, and acidulated with nitric acid, is
tested with solution of argentic nitrate.
Phenol or carbolic acid may in most instances be detected by its
(xlor; smaller quantities may be readily recognized by agitating
the acid with a small quantity of warm water, and, after being
allowed to cool, and the addition of a little ammonia-water,
exposing the solution to the vapor of bromine, when a deep
blue coloration will he pnxluced ; or, about 5 cubic centimeters
of a saturated solution of salicylic acid are poured into a test-
tube, in which 2 cubic centimeters of strong hydrochloric acid
and a little granular potassium chlorate have just been mixed ;
some ammonia- water is then, by means of a pipette, carefully
placed upon the mixture; the former will assume a reddish or
brownish tint, if carbolic acid be present.
Detection of Salicylic Acid in Syrnps, Extracts, Articles of
Food, etc.:
A sufficient quantity of the substance to be examined is mixed
or diluted with water, if necessary, and evaporated at a gentle
heat, in order to expel any alcohol which may be present. After
biung allowed to cool, the clear filtered liquid is strongly acidu-
lated with sulphuric acid, and subse^iuently shaken with ether.
The ether is then carefully separated from the aqueous liquid,
allowed to evaporate spontaneously, and the residue dissolved in
a little water and tested with ferric chloride; if salicylic acid be
present a deep violet coloration will be produced.
ACIDUM SUCCINICUM.
Succinic Acid.
Gcr. Bernsteinsaure ; Fr. Acide succiiiiqiie ; Sp. Acido succinico.
cii,-C()-on
CJIA - I ; 118.
CII,-CO-OH
Colorless, oblique-rhombic j^risms, or rhombohedral plates, with-
out odor when pure, and with a more or less strong odor when
the acid is obtained from amber by sublimation, and is only
imperfectly freed from the empyreumatic oils.
It melts at 180^ C. (^6h^^ F.), but may be sublimed at a much
ACIDA. 183
lower temperature, and boils at 235^ C. (455° F.), at the same
time undergoing decomposition into water and succinic anhydride.
When heated upon platinum-foil, it emits irritating, inflammable
vapors, without the separation of carbon, and is entirely dissi-
pated at a red heat.
Succinic acid is soluble in 18 parts of water at 17° C. (62.6° F.)
and in 0.8 part of boiling water, in 10 parts of cold 90 per cent,
alcohol, in 1.5 parts of boiling alcohol, and in 80 parts of pure
ether, but is insoluble in carbon bisulphide, petroleum benzin, and
turpentine oil (distinction from benzoic acid); it is also soluble in
warm nitric acid, and in concentrated sulphuric acid, without de-
composition, and, if i>erfectly pure, produces with the latter no
coloration.
The aqueous solution of the acid has an acid taste and reaction,
and, when carefully neutralized with ammonia-water, yields on
the addition of a solution of ferric chloride a reddish-brown, floc-
culent precipitate of basic ferric succinate, which is dissolved
upon the addition of hydrochloric acid (further distinction from
benzoic acid).
Examination :
Fixed Admixtures. — If a residue remains when the acid is
heated upon platinum-foil, a small portion of it should be com-
pletely incinerated in a porcelain crucible, and the residue, when
cold, tested with moist turmeric- as well as with red litmus-paper.
It is then divided into two parts, one of which is mixed with a
little strong alcohol, and this ignited ; a green color of the flame,
especially toward the termination of the ignition, indicates boracic
acid; the second portion of the residue is dissolved in a small
quantity of water acidulated with a few drops of nitric acid ; efter-
vescence would indicate carbonates^ originally present as such, or
produced by the decomposition of some organic salts, if carboniza-
tion occurred upon ignition. The acid solution is then tested in
separate portions, with argentic nitrate for chlorides^ and with
barium nitrate for sulphates^ which will be indicated in either
instance by an ensuing white precipitate.
Ammo7iiu7n salts are detected by the odor of ammonia, and by
white fumes when a glass rod, moistened with acetic acid, is held
over the orifice of the test-tube, when the acid is heated in solu-
tion of potassium hydrate.
Foreiffu orf/anic acids may be detected as follows :
Tartaric acid will be indicated by a white crystalline precipitate
of acid ammonium tartrate, upon partial saturation of the acid
with ammonia- water ; or, by the production of a white crystalline
precipitate of acid potfussium tartrate, upon the addition of a few
drops of a concentrated solution of potassium acetate to the aqueous
solution of the acid.
Oxalic a/:id will be detected in the aqueous solution of the acid,
after ueutralizatioa with ammonia- water, and the addition of a
184 MANUAL OF CHBHIOAL ANALYSIS.
solution of calcium chloride, calcium sulphate, or lime-water, 1
the formation of a white precipitate, which is insoluble in acetic
acid, or a solution of ammonium chloride.
Citric (fC'ii will be detected by the addition of a few drops of a
solution of the acid to an excess of lime- water, so that the alka
line reaction still predominates, and aubsequently heating to
boiling; an ensuing white precipitate will indicate citric acid.
Benzoic acid may be delected by its solubility in carbon bisul-
phide or warm petroleum bonzin; or by its separation, when the
precipitate produced in the neutralized solution of the acid by
ferric chloride is digested with a little hydrochloric acid,
Suf/ar may be detected, in tbe absence of other organic acids or
their salts, by a corbouaceous residue on gently heating a little of
the acid on platinum-foil; and, in the presence of other organic
acids, by heating a sroall portion of the solution with a few drops
of dilute sulphuric acid, and subsequently testing with Fehling's
solution, when a red precipitate of cuprous oxide will be formed.
Metallic impurities may be detected in the concentrated solution
of the acid, by a dark coloration op a precipitate upon saturation
with hydrogen sulphide, or upon subseciuent supersatu ration with
ammonia- water.
The following may serve as a general test for the purity of
succinic acid : 1 part of the acid is dissolved in 15 parts of strong
or al>3olute alcohol ; the solution is aided by dipping the test-tube
in hot water ; when cold it \a divided into two parts, one of which
is mixed with an equal volume of chloroform, the other with an
equal volume of ammonia-water; a complete solntion must take
place in the first test, and a clear mixture in the second, otherwise
one or more of the above-mentioned adulterations are present.
When a crude acid, containing empyrcumatic substances, has to
be examined, it is first agitated and washed with a little ether,
and is then dissolved in boiling water, and the solution, wbea
cold, passed through a filter previously moistened with water.
ACHJUM anLFHURICUH.
Sulphuric Acid.
Gcr. Scliwefelsinre ; Pr. Adds lulfurique ; 9p. Acidn sulflSrico.
'«\0H' ''^■
n.so. - so-<
A dense, colorless, inodorous, highlv corrosive liquid, of a spec.
grav. of 1.8428 at 15° C. (Sit; F.). When the pure acid of the
above composition is heated, it is partially decomposed into water
and sulphur trioxide. This dissociation increases with increase
of temjrerature, until at SiiS"* C. (640.4^ F.) a liquid acid of cou-
etant composition and boiling-point distils over without further
ACIDA. 185
alteration, which contains from 98.4 to 98.8 per cent, of abso-
lute acid. The commercial concentrated acid usually has a spec,
grav. varying from 1.834: to 1.836 at 15^ C. (59° F.), correspond-
ing to from 93 to 94 per cent, of absolute acid. Two strengths
of sulphuric acid are officinal, an acid having a spec. grav. not
less than 1.840 (1.836-1.840 Pharm. Germ.; 1.843 Brit. Pharm.),
and containing not less than 96 per cent, of absolute sulphuric
acid; and Acidum Sulphuricum Dilutum, spec. grav. about 1.067
(1.110-1.114 Pharm. Germ.; 1.094 Brit. Pharm.), containing 10
per cent, of absolute acid.
Sulphuric acid has a strong attraction for water, absorbing it
from the atmosphere, and withdrawing it or its elements from
organic compounds immersed in, or mixed with, the acid; sul-
phuric acid, therefore, when in contact with organic substances,
or with air containing dust, gradually loses its colorless appear-
ance, and becomes more or less brown, and rapidly chars and
destroys most organic substances.
Sulphuric acid is miscible with water, glycerin, alcohol, and
other solvents, with evolution of heat, and produces, with most
organic liquids, a more or less vehement decomposition ; in its
relations to other compounds, it maintains the character of one of
the strongest acids, its affinity for bases being so powerful jis to
withdraw them from most of their compounds, forming sulphates,
which, with the exception of those of barium, strontium, calcium,
and lead, are freely soluble in water, the latter three being very
sparingly soluble, while barium sulphate is practically insoluble
in both water and dilute acids. By the same powerful affinity,
sulphuric acid, in its dilute condition, dissolves most of the metals
(iron, zinc, magnesium, cobalt), with the evolution of hydrogen
and formation of sulphate of the metal ; when concentrated it
does not act in the cold upon many of the metals, but, when
heated, most of them (copper, mercury, silver, lead, tin, etc.) are
attacked, with the evolution of sulphur dioxide, in consequence
of the reduction of the acid by the liberated hydrogen at the high
temperature.
In consequence of its affinity for water, a piece of pine wood
dipped into concentrated sulphuric acid becomes black from sepa-
ration of carbon, and when a fragment of cane-sugar is placed in
contact with the acid the latter will likewise assume a dark colora-
tion, and upon heating develop the odor of sulphurous acid.
When one drop of the acid is diluted with a test-tubeful of water,
a white precipitate will be produced on the addition of a few
drops of a solution of barium chloride.
lamination:
Fixed impurities are recognized by a residue after the complete
evaporation of a small quantity of the acid in a platinum or
porcelain capsule.
Lead is indicated by a white turbidity taking place upon the
AL oy CHEMICAL ,
careful admixluro of
one part oTtne
acid with about four or fi
its volume of alcoliol, Anotlier
nietliod of readily recognizing the
presence of lead in sulphuric acid
is, to about half fill a small conieal
cvlinder with concentrated hydro-
chloric acid, and then to place feelow
the acid, by means of a pipette, a
nearly equal volume of the SHiphurio
acid, with care that the fluids do not
mix (Pig. 79) ; an ensuing white tur-
bidity nt the junction of the two fluid^
would confirm the presence of lead.
The presence of metallic impnri-
■^■^^^^^^■^^■^ ties in general may be detected, after
the previous dilution of the acid
wini Kevenii limes its volume of water, and warming it gently, by
saturating with hydrogen sulphide. The liquid, after standing
for several hours, is filtered from any precipitate which
may have been formed, subsequenth' supersaturated
with ammonia- water, ammonium sulphide added, and,
when required, further examined by the methods de-
scribed in the course of analvtical investigation (pages
51 to 59).
Jrsemc maybe detected in the acid, previously diluted
with about five times its volume of water, and gently
warmed, by the production of a yellow precipitate upon
saturation with hydrogen sulphide, as indicated in the
preceding teat. If specially sought for, it may, together
with sulphurous acid, be readily delected by heatiuff
the diluted acid, in a test-tube, with a few fragments m
pure zinc, and placing over the orifice of the tube a cap
of bibulous paper moistened with a drop of solution of
argentic nitrate (Fig. 80); the production of a black
stain upon the paper will indicate either arsenious or
sulphurous acids.
Nitric and uttrous acids may be detected by the addi-
tion of a drop of indigo solution to a small portiou of
the acid, and gently warming, when decoloration of the
liquid will ensue; or a crystal of ferrous sulphate ia
added to the acid, or a solution of the latter salt carefully
poured upon it, without mixing, so as to form two dis-
tinct layers (Fig. 81), when, in either case, a brown
coloration of the crystal, or a brown zone at the point
of contact of the two liquids, will indicate the above-mentioned.
impurities.
By carefully mixing the concentrated aeid with about half its
AOIDA. 187
volume of a solution of 5 drops of pure aniline in 25 cubic cen-
timeters of dilute sulphuric acid, so as to form at first two layers,
the mixture will assume a rose-red coloration in the presence of
nitric or nitrous acids. A special test for nitric acid consists in
the production of a rose-red coloration on the addition of a few
drops of an aqueous solution of brucine.
Fig. 81.
Hydrochloric acid will be detected in the acid, diluted with
twenty times its volume of water, by the production of a white,
curdy precipitate on the addition of solution of argentic nitrate.
Estimation :
Sulphuric acid may be most conveniently estimated volumet-
rically by the process of neutralization. From 2 to 3 grams of
the strong acid, or a corresponding quantity of dilute acid, is
accurately weighed in a beaker, about 50 cubic centimeters of
water, and a few drops of litmus «^olution added, and a normal
solution of potassium or sodium hydrate (page 87) allowed to flow
into the liquid from a burette until, with constant stirring, a per-
manent blue tint is produced. Sulphuric acid being dibasic, 1
cubic centimeter of the normal alkali solution corresponds to
0.049 gram II,SO^, which, multiplied by the number of cubic
centimeters of normal alkali solution employed, will give the
amount of absolute acid in the specimen under examination, and
from which the percentage strength may be calculated. By deter-
mining the spec. grav. of the acid, the correctness of the result
may be verified by comparing it with the percentage strength of
an acid of the same specific gravity, as indicated in the subjoined
table, page 189.
To neutralize 2.45 grams of the strong officinal acid, diluted
188 MANUAL OF CHBMIOAL ANALYSIS.
with about 10 volumes of water, not less than 48 cubic centimeters
of normal solution of potassium or sodium hydrate should be
required; and to neutralize 9.8 grams of the officinal diluted acid
should require from 19.2 to 20 cubic centimeters of normal alkali.
The gravimetric estimation of sulphuric acid is readily accom-
plished, although less quickly than by the preceding method, by
its conversion into barium sulphate. To a weighed quantity of
the acid, largely diluted with water, a few drops of hydrochloric
acid are added, the mixture heated to boiling, and subsequently
a solution of barium chloride added until no further precipitate is
produced. After standing for some hours, the precipitate is col-
lected on a filter, thoroughly washed with hot water, dried, and
finally ignited at a red heat. 100 parts of barium sulphate corre-
spond to 42.06 parts of sulphuric acid, H,SO^, or 34.33 parts of
sulphuric anhydride, SOj.
Rules for the Dilution of Sulphuric Acid.
If a strong acid a has to be diluted with water or with a weaker
acid c, in order to obtain an acid of some special strength 6, the
following rules are applicable: The difference in percentage
strength is sought on the one hand between a and ft, and on the
other between ft and c, and a and c then mixed in the proportions
represented by the difference in the respective numbers. It must
be observed, however, that when the difference between a and ft
is greater than between ft and c, less of a than of c must be taken
in order to obtain ft; and when the difference between a and ft is
less than between ft and c, more of a than of c must be employed
in order to obtain ft; for example :
I. Sulphuric acid containing 29 per cent, of absolute acid is to
be mixed with water to form an acid containing 25 per cent, of
absolute acid :
a. ft. c.
29 per cent. 25 per cent. 0 per cent.
Difference 4 25
25 parts of 29 per cent, acid are therefore to be mixed with 4 parts
of water, or
100 grams of sulphuric acid = 29 grams H^SO^.
16 '' " water =»
^ ■ ■ ^ ■ ■— ■ — — ■ ■ ■ ■■■■II I .. — ^fcl^M^
116 grams of sulphuric acid = 29 grams H^SO^.
or 100 " " " " = 25 " "
II. Sulphuric acid containing 32 per cent, of absolute acid is to
be mixed with an 8 per cent, acid to form an acid containing 14
per cent, of absolute acid :
ACTDA.
189
Diflference
€L, b. C,
82 per cent. 14 per cent. 8 per cent.
18 6
(3)' (1)
1 part of 32 per cent, acid is therefore to be mixed with 3 parts
of 8 per cent, acid, or
100 grams of sulphuric acid e. 32 grams H,SO^.
300 " " *' " — 24 " "
400 grams of sulphuric acid e. 56 grams H^SO^.
or 100 *' " ** " — 14 " "
Table of the quantity by weight of Sulphuric Acid (ff^SO^)^ and the
corresponding amount of Sulphuric Anhydride (SO^), contained in
100 partt by weight of Aqueous Sulphuric Acid of different specific
gravities {Otto).
Temperature 150 C. (590F.).
Spectflc
Per ct. ,
Percent.
Speelflc
Per ct.
Perceot. '
Specific .
Per ct.
Percent.
gravity.
of
HS8O4.
100
of
80,.
giavltjr.
of
H,804.
66
of 1
80,.
gruviiy.
1
of
HjSO^.
82
of
80,.
1.8426
81.68
1.678
58.87
1.289 !
26.12
1.842
99
80.81
1.557
65
58 05
1.281 ,
81
25.80
1.8406
98
80.00
1.545
64
52.24
1.228
30
24.49
1.840
97
79.18
1.584
68
51.42 I
1.215
29
23 67
1.8884
96 !
78.86
1.528
62
50.61
1.2066
28
22.85
1.8876
95
77.55
1.512
61
49.79
1.198
27
22.03
1.8856
94 1
76. 18
1.501
60
48.98 :
1.190
26
21.22
1.884
98
75.91
1.490
59
48.16
1.182
25
20.40
1.881
92
75.10
1.480
58
47.84
1.174
24
19.58
1.827
91
74.28
1.469
57
46.58
1.167 '
23
18.77
1.822
90
73.47
1.4586
56
45.71
1.159
22
17.95
1.816
89
72.65
1.448
55
44.89 ,
• 1.1516
21
17.14
1.809
88
71.43
1.488
54
44.07
1.144
20
16.82
1.802
87
71.02
1.428
58
48.26
1.186
19
15.51
1.794
86
70.10
1.418
52
42.45
, 1.129
18
14.69
1.786
85-
69.88
1.408
51
41.68
1.121
17
18.87
1.777
84
68.07
1.898
50
40.81
1.1186
16
13.06
1.767
88
67.75
1.3886
49
40.00 1
' 1.106
15
12.24
1.756
82
66.94
1.379
48
89.18
1.098
14
11.42
1.745
81
66.12
1.370
47
38.36
1.091
13
10.61
1.734
80
65.30
1.361
46
87.55
1.083
12
9.79
1.722
79
64.48
1.851
45
36.73 1
1.0756
11
8.98
1.710
78
63.67
1.342
44
35.82 1
1.068
10
8.16
1.698
77
62.85
1888
43
; 85.15
1.061
9
7.84
1.686
76
62 04
1.324
42
84.28
1.0.-,86
8
6.53
1.675
75
61.22
1.315
41
' 38.47
1.0464
7
5.71
1.668
74
60.40
1.806
40
32.65
1.039
6
4.89
1.651
1 78
59.59
1.2976
39
31.83
1.032
1 5
4.08
1.689
72
58.77
1.289
88
31.02
1.0256
4
3.26
1.627
71
57.95
1281
37
30.20
1.019
8
2.445
1.615
70
57.14
1.272
36
29.88
1.013
2
1.68
1.604
69
56.82
1.264
85
. 28.58
1.0064
: 1
0.816
1.592
68
55.59
1.256
84
1 27.75
1.580
i 67
54.69
1.2476
88
26.94
1
1
i
190 MANUAL OF CHEMICAL ANALYSIS.
With the decrease and increase of temperature, the specific gravity of sulphuric
acid suffers a corresponding increase f>r decrease, amoanting for each degree
of tlie centigrade thermometer in cither direction :
For acids of a specific gravity of 1.842 to those of 1.786 to about 0.0014
1.777 '* 1.668 " 0.0013
1.651 ♦* 1.306 " 0.001
1.297 ** 1.215 " 0.00075
»* .* •* k«
1.206 ♦* 1.144 " 0.00045
1.136 '* 1.C68 " 0.00047
ACIDUM SULPHTTROSXTM.
Sulphurous Acid,
Ger. Schweflige Saure ; Fr. Acidc sultureux ; 8p. Acido snlfuroso.
A colorless liquid, po.ssessiiig the characteristic suffocating odor
of burning sulphur. The most concentrated acid which can be
obtained by saturating water with the gas at ordinary tempera-
tures contains 9.54: per cent, of sulphur dioxide, and has a specific
gravity of 1.046. The officinal acid is stated to have a specific
gravity of 1.022 to 1.028 (1.04 Brit. Pharm. =. 9.2 per cent SO,),
corresponding to about 5.7 per cent, of sulphur dioxide. It pos-
sesses a very acid, sulphurous taste, and has a strongly acid reac-
tion upon litmus, which it first reddens and afterwards bleaches.
When heated to boiling, it loses sulphur dioxide, becoming finally
completely volatilized ; and when exposed to the light it becomes
gradually decomposed with the formation of pentathionic acid,
IIjS^Oj, and in contact with the air is readily oxidized to sulphuric
acid.
Sulphurous acid possesses a strongly reducing action, to which
are due also its bleaching properties; it separates metallic gold,
silver, and mercury from solutions of their salts, and liberates
iodine from a solution of potassium iodate, which imparts a blue
color to mucilage of starch. When hydrogen is generated by the
action of dilute sulphuric acid u])on a few fragm *nts of pure metal-
lic zinc, contained in a test-tube, and a few drops of sul[)hurou8
acid arc ad<led, the latter will become reduced to hydrogen sul-
phide, and impart a black stain to a piece of bibulous paj^er moist-
ened with a solution of j^lumbic acetate, and placed over the
mouth of the tube.
Examination :
Sn/pln/rir nn'd may be detecteil by a white ])recipitate, insoluble
in hydrochloric acid, u])on the adilition of a soluticm of barium
chloride. The amount of sulphuric acid present should not be
sufficient to produce more than a very slight turbidity, when to
10 cubic centimeters of sulphurous acid 1 cubic centimeter of
diluted hydrochloric acid is added, and subsequently 1 cubic cen-
timeter of test-solution of barium chloride.
ACIDA.
191
Estimation :
The strength of an aqueous solution of sulphurous acid may be
approximately determined by ascertaining its specific gravity, and
subsequent reference to the subjoined table, or, more accurately,
by the following method of volumetric estimation :
About 2 grams of the acid, diluted with 50 cubic centimeters
of water, arc placed in a flask, a little mucilage of starch added,
and then a decinormal solution of iodine, the exact strength of
which has been previously determined, page 93, allowed to flow
into the liquid from a burette until, with constant stirring, a per-
manent blue coloration is produced;* the sulphurous acid be-
comes thus oxidized to sulphuric acid, according to the equation :
I, + HjSO^ -h H,0 - H,SO, + 2HI.
254 82
(127) (41)
From the number of cubic centimeters of iodine solution emploj^ed,
the amount of sulphur dioxide or of absolute sulphurous acid
may be calculated ; one cubic centimeter of the iodine solution,
corrected if necessary by its proper factor, page 95, corresponding
to 0.0032 gram of sulphur dioxide, SO,, or 0.0041 gram of abso-
lute sulphurous acid, H^SO,.
The U. S. Pharmacopoeia directs that 1.28 grams of sulphurous
acid, diluted with 20 volumes of water, and a little mucilage of
starch added, should require the addition of at least 14 cubic cen-
timeters of the volumetric solution of iodine before a permanent
blue tint is developed, corresponding to at least 3.5 per cent, of
sulphur dioxide.
Table of the parts hy weight of SvJphnr Dioxide contained in 100 parts
by weight of aqueous Sulphurous Acid, of different specific gravities
(Anthon).
Temperature 150 C. (590 F.).
Specific gniTitj.
Per cent, of SOj.
1.046
1.086
1.031
1.027
1.023
9.54
8.59
7.63
6.68
5.72
Specific grarltj.
1.020
1.016
1.013
1.009
1.005
Per cent of SO^.
4.77
3.82
2.86
1.90
0.95
♦ On accoant of the volatility of sulphurous acid, it is important that such
estimations be performed as quickly as possible, in order to prevent loss by
evaporation.
hiu
mani;ai. op ciirmical analysis.
ACIDUM TANinCnM.
Tnnnir Acid, Tanuin,
til I (JMbftitiirr ; Kr. Ari»lr tAimuiuo : Sp. Acido tanico.
»"..ll.n'».
\ lii.'.i pli.Mr.. IiimMt. poroiis. :iinl iiuKloroiis masses, or tli in shin-
., . . li. V 1^1 :» p:»:r ».•.1■^^ni^ll vrllow color, jiinl fofble, mild odor*
^■.■,w. ^ ...'■nl^;iu»i with :\ \i\\\\\ i»(K»r oi^ imIiod: when heated upon
,,i -.i^... ^luiui ;uul hisrs. s\N oils Up, :iih1 Imrns away without
...... u li 1'^ s.^luMr in r» p;irts of waior or glycerin, in 0.6
.. ■ i-.\; .- : .t.. :: 'n'v> lii.-jii ii> I'w:; "wr'-i^ii* v^l" diluted alcoliol,
..; . ^. \ ■-.s \ N.N ..:• »■ :;'. Iv^.i.i.v: «:»:»' ;.'..ii ii. lu^ilinjT aleohol ; it
i- ;., v.i. .,1 \ »:.. ..S.I '.. :iSv,. i-.:o ;4:vv»:^i'. .';]!. "J iH Commercial
,-. I-.. •.:■.. ■. .. .^^. ...v.^ ;.:-r .:; :.:\si- ..:r oiLcr. c:. .i>rv^form, carVnin
1. ■.«. .N ;>. . •. ... :,;■.. :; i l.xoi': j*i!i; Vi».fti:ie oils, lis
V. .1 .» . .•.■-' . i».\'.»..'.-^ ■. . 'S'.. V :■;■. :vi. 'Vi*. liiij graduiilly
.1. i -. . .;■. :.:.•!. '..\ \» .•,■- .\.^iS»v. I. '1': :..T: '.• SUiTerS pFC-
. .1 '. ^ .-, ■ K- .'. s- N •.•..; ^ :;■: :..■';":. :K:1.J>. f;rid fi'Tm?
■., . ■ . . . .ui ,n ;•.;» V ■■. ■ k'. .•; . ■■..•*:*.> S. '.'."lllCr V SOiUbiC
.\ , I :■,.■.! ^ . .\ '.'. ^» • .-. . .-». , .* ■:>«> ■:> I . : iH one? w:th
V v.. . ,; .•..;.;^i .: ■;> <; •. IjT.jl ill? of
.v .-. ..: ■ ■:: l:..."C' SU'l ■::"». liTid
I • •
1 1 , ■. . .\ ■. '. *
1. II'. I, • :■. V ■ ■.■■.
■ I . , ■ . • . »* »i . '.
I. . ■ r. '. . ■
I
■ . . ■, ■ I
• . \ i ■ .
i I
1
' . i ■ ■< .
"»? V
- - .:> . :*'«Ti.:ij::i-.y
■ . ■ • \ 1 ■•. II. r
X . . 'm .!!>;:* 111''.
.. i: I 11 <\^'\.
'> :\\\ 1" I ' .
'. i)j i-.M.r:-
1?^ ^••.•A Vl •i*i
, .r . (.
I •
'%! ...1.1
-■•■■» *^ I •
I • * ••& .* I
. • • ' • « ■•
.-..^i 'ifinr ATW Ijli
l>. i> • • «la^li
ACIDA. 193
the other by dilution with water; if any such adulterations be
present, they may be separated and recognized by making two
solutions of the acid, one in strong alcohol, when gum, sugar, and
dextrin will remain behind, and another one in boiling water,
when resinous substances will remain undissolved or be separated
on cooling.
Estimation :
In consequence of the variable nature of tannic matters as de-
rived from different sources, and the impurities with which they
are frequently accompanied, their exact quantitative estimation
in technical pn^ucts, vegetable extracts, etc., is often attended
with considerable difficulty. Of the various methods proposed,
two of the less complicated will here be given, which, however,
in most instances afford sufficient! v accurate results.
I. The substance to be examined is extracted with strong
alcohol, the alcoholic liquid evaporated at a gentle heat to the
consistence of a soft extract, and the residue taken up with just
sufficient water to insure the complete solution of thci tannic mat-
ter. To the clear aqueous solution a solution of neutral plumbic
acetate is then added until a precipitate ceases to be produced, the
precipitate collected upon a tared filter, washed three or four times
with small portions of water, dried at 100° C. (212° F.) until of
constant weight, and its weight finally determined. The precipi-
tate is then removed from the filter, the latter, together with a
little ammonium nitrate, brought into a porcelain crucible and
ignited, and afterward the precipitate added, and the whole ignited
at a strong heat until the weiglit remains constant. The weight
of the ignited plumbic oxide, subtracted from the previously
determined weight of the lead precipitate, will represent the
amount of tannic acid, together with other organic acids or bitter
principles precipitable by plumbic acetate, which may be contained
in the substance under examination.
II. This method depends upon the precipitation of the tannic
acid as zinc tannate, and the estimation of the latter by means of
a solution of potassium permanganate. A solution of zinc acetate
in an excess of ammonia water yields with tannic acid a precipi-
tate of zinc tannate, insoluble in an excess of the reagent, in water
or ammonia- water, but is not precipitated by alcohol, glycerin,
potassium or calcium tartrate, albumen, or by ferric and ierrous
salts of the organic acids; with gallic acid and aluminium salts it
yields a precipitate, which, however, is soluble in an excess of the
reagent and in ammonia-water.
The solutions required in this process of estimation are: 1. A
solution of zinc acetate, prepared by dissolving 10 grams of crys-
tallized zinc acetate in 200 cubic centimeters of water, and the
subsequent addition of 130 grams of ammonia- water, spec. grav.
0.960. 2. Diluted sulphuric acid, prepared by mixing 1 part of
sulphuric acid, spec. grav. 1.84, with 5 parts of water; ana 3. A
13
194 MANUAL 0? CHBHICAL ANALySIS.
solution of 1.333 grams of crystallized potassium permanganate ia
1 liter of water. In order to determine the oxidizing power of the
permanganate solution, a solution of pure tannic acid of known
strength is prepared ; for instance, 1 gram of pure tannin dis-
solved in 1 liter of water. If.it be found, for example, that 20
cubic centimeters of this tannin solution require the addition of
10 cubic centimeters of nermangauate solution in order to pro-
duce a permanent pink tint, then 1 cubic centimeter of the per-
manganate solution corresponds to 0.002 gram of pure tanuin.
The estimation is then performed as follows: To about 50 cubic
centimeters of the liquid to be examined, a slight excess of the
solution of zinc acetate above that required to completely precipi-
tate tiie tannin is added, the mixture heated to boiling, subse-
quently evaporated to about one-third of its volume, and allowed
to cool. The precipitate of zinc tannate is then collected on a
filter, washed with hot water, subsequently dissolved in diluted
sulphuric acid, and the solution titrated with potassium perman-
ganate until a permanent pink tint is produced. If, for example,
15 cubic ceulimelers of the potassium permanganate solution are
employed, and, as by the above determination, 1 cubic centimeter
of permanganate solution corre-sponds to 0.002 gram of tannin,
consequently 15 cubic centimeters of permanganate solution cor-
respond to 6.002 X 15 -> 0,03 gram of tannin. As this amount is
contained in 50 cubic centimeters of the liquid under examination,
100 cubic centimeters will contain O.Ot; gram, or O.OC per cent, of
pure tannic acid.
Tahlk of the amounl by weight of pure Tannic Acid rontaiiud in IW
pnrtt Jy tvtigkt of \tt aqveons loluttvai of different tpecijic grarilies
( If a tamer).
TcmpersluTC 1.^° C. (59o F.).
tV'li-
F>r(»l.
Bpeolfle
P.r ««.
eiMciae
Per <»1.
epteiao
P.r«Bt,
frtfliT-
.dd.
er„ii,.
Kid.
gnTUj-
' ," " "
er„ll7.
°«.d.
1.0010
0.3S
1.0211
S.25
1.0410
10.25
1 .0036
13.36
i.ooao
0,50
1.0322
n.50
1.0437
10.50
1 .0036
15. SO
1.0080
0.75
1.0333
6.76
1.0487
10.75
1.0040
15.75
1 .0040
1.00
1.0343
0.00
1.0447
11.00
1.0056
16.00
l.OOfiO
LS.-!
1.03.^9
fl.as
1.0468
11.25
1.OO60
16.35
l.OORO
l.SO
1.0363
6.50
1.0468
11.50
1 .0077
16.50
l.OOTO
1.76
1.0873
6.76
1.0470
It. 75
1.0088
18.76
x.tow
8.00
1.03S3
7.00
1.04S9
12.00
1.0098
17.00
1.(090
S.3S
1.03118
7.25
.1.0409
13.25
1.0709
17.35
I.OlilO
a. no
1.(1304
7.50
1.0.510
18.60
1.0710
17.50
l.OUO
2,78
1.0814
7.75
1.0530
12.75
1.0780
17.75
i.oiao
3.00
1.0834
e.oo
1.0530
13.00
1.0740
18.00
1.0180
8. as
1.0384
8.25
1.0641
13.25
1.07.'>1
16.35
l.OHO
8.50
1.0345
8.50
1.0.5.11
lB.r,0
1.0781
18.30
l.OISO
8.75
1.03n5
8.75
1.0563
13.75
1.0772
18.75
1.0100
4.00
1.0805
6.(10
1.0573
14.00
1,07B3
19.00
1.0171
4.26
1.037.1
9 35
1.0.'>e8
14.85
1.0793
19. S5
1.0181
4.60
1.0388
9.50
1.0593
14.50
1.0803
19.60
l.OIBl
4.75
1.03M
9.75
1.0604
14.75
1.0814
19.75
J.OSOI
6.00
1.0406
10.00
1.U614
15.00 ,
1.0934
20.00
ACIDUM TAHTARICTTM.
Tartaric Arid.
Ger. Weinsaure ; Fr. Aclde lurtnrique ; Sp. AcMn iBrtarico.
CH(OH)-CO-OH
C.H.O, = I ; 150.
cn(on)-co-OH
Fio. S3.
Colorless, transparent, monoclinic prisms (Fig, 82), permanent
in the air; they contain no water of crysljilliaation, and, when
cautiously heated in a glass tube, fuse at 135° C. (275° K.) tu a
transparent, vitreous, very deliquescent
mass of metalartaricaeid, CjHjO, ; when
elrongly heated, with exposure to the air,
they are decomposed with the evolution
of inflammable vapors of a peculiar odor,
reaeinbtiug thatof burnt sugar, and with
the xeparation of carbon, and are finally
wholly dinsipated.
Taftaric acid is soluble in 0.7 part of
ooid, and in 0.6 part of boiling, water;
in 2.5 parts of cold, and in 0.2 part of
boiling, alcohol ; in 36 parts of absolute
alcohol, in 23 parts of commercial ether, or 250 parts of absoluie
ether; and is nearly insoluble in chloroform, Iwnzol, and benzin.
lis solutions possess a strongly acid taste and reaction, and, when
dropped iuto solutions of neutral potassium sails, give rise to llie
formation of a while granular precipitate, at once in concentrated
solutions, and after a time in diluted ones. This reaction, how-
ever, does not take place in solutions containing free mineral
aoids or acid salts thereof. When solution of tartaric acid is
dropped into lime-water, so that the alkaline reaction predomi-
nates, a white turbidity occurs (distinction from citric acid), which
disappears again upon the addition of solution of ammonium chlo-
ride (distinction from racemic acid), and also upon the addition of
acetic acid (distinction from oxalic acid); solution of calcium sul-
phate remains unchanged upon the addition of tartaric acid ^addi-
tional di.'ilinction from oxahc and racemic acids).
Crystals of tartaric acid, when immersed in concentrated sul-
phuric acid, dis-solvc gradually without coloration, unles.s warmed,
when they become black, anil; on more strongly heating, with the
development of carbon monoxide, carbon dioxide, and sulphurous
acid gas.
HzunlnEtlon ;
Sails. — An admixture of sails is recognized by the addition of an
equal volume of alcoliol to a cold saturalcd aqueous solution of
the acid, or by dissolving the powdered acid in B parts of strong
19ii
MANUAL OF CHEMICAL ANALYSIS.
alcnbol ; a complete and permanent solution must ensue in eiU
case.
Sulphuric acid or sulpliates iriay be detected in the diluted solu-
tion, to wliicli a little hydrochloric add has been added, by a
white turbidity with barium nitrate. If 10 cubic centimeicrs of
a strong solution of lartnric ncid be employed for the test, no pre-
cipitate should be produced within five minutes upon tlie subse-
quent addition of 1 cubic centimeter of tcsl-solutiou of barium
chloride, and an excess of hydrochloric acid.
C/ilnrides may be delected in the diluted solution, by a white
precipitate, insoluble in nitric acid, on the addition of a solution
of argentic nitrate.
Oxalic acid or oxnlnfes may be detecled in the concentrated
aqueous solution of the acid, by a while precipitate when tested
with solution of calcium sulphate.
Calcium salts may be detected in the diluted solution, pre-
viously nearly neuirnlized with ammonia-water, bo ihat the acid
reaction still predominates, by a white precipitme on tlie Bildilion
of ammonium oxalate,
Melallie impurities (copper or lead) are detected by a brown or
blackish coloration or precipitate, when a concentrated aqueous
solution of the acid is saturated with hydrogen sulphide; after
filtering, if necessary, and subsequent super-saturation with am-
monia-water, an ensuing dark coloration would indicate iron.
Estimation;
One hundred parts of tartaric ncid require for exact neutrali»t-
tion H2.2 parts of nuhydroua (xuassiuui carbonate, 133.33 parts of
crystallized potassium bicarbonale, llKl.Btt pans of crystnlliawd
sodium carbonate. 112 parts of .sixliurn bicarbonate, and 63,33
parts of magnesium carbonate.
The estimation of tartaric acid may also be conveniently ac-
complished volumetricaliy with sufficient accuracy, since, unlike
citric acid, its point of neutralization as indicated by means of
litmus may be distinctly observed.
About 3 grams of the crystallized acid, accurately weighed, are
dissolved in about 50 cubic oentimeiers of water, a few drops of
litmus solution added, and a normal soluiiou of potassium or
sodium hydrate (page 87) allowed to (low into the liquid from a
burette until, with constant stirring, a distinct blue tint is pro-
duced. Tartaric acid being disbasic, one cubic centimeter of
normal alkali corresponds to 0.075 gram of the crystallised acid,
and from the number of cubic centimeters of alkali solution cm-
ployed, the purity or percentage strength of the ncid may be
readily calculated. If 3.7.'i grams of acid, and a strictly normal
Holution of alkali are employed, the number of cubic centimeters
of the latter required for neulraliiwlion, when multiplied by 2,
will represent at once the peroentage purity of the acid.
Another method of estimation consists in adding to a solution
ACIOA.
197
of 1 part of tartaric acid in 3 parts of cold water, a solution of 1
part of potassium acetate in 3 parts of cold water, and subse
quently adding a volume of alcohol equal to that of the whole
mixture; after being allowed to stand for 2 hours, the white,
crystalline precipitate of acid potassium tartrate is collected upon
a tared filter, well washed with diluted alcohol, and dried at 100°
C. (212^ F.), when it should weigh between 1.25 and 1.26 parts.
Table of the parts by weight of crt/ntallized Tartaric Acid contained in
100 parts by weight of aqueous solutions of the acid of different specific
gravities {Gerlach).
Temperature 150 C. (59^ F.).
Specifle
Percent, of
Sp^clflc
Per c<»nt. of ^
Specifle
■ Per c^nt of
gnrUy.
tartaric acid.
• <
gravity.
tartaric arid. '
K'rar ty.
1.2019
tartaric acid.
1
1.0045
1
1.09693
20 1
39
1.0090
2
1 . 1020
21 !
1.20785
1 40
1.0136
8
1 . 1073
2-3
1.2138
41
1.0179
4
1.1124
28 '
1.2198
42
1.0224
5 1
1.1175
24 ,
1.2259
43
1.0273
6
1.1227
25
1.2317
44
1.0322
7
1.1282
26 I
1.2377
45
1.0871
8
1.1338
27
1.2441
46
1.0420
9
1.1393
28 1
1.2504
47
1 04692
10
1.1449
1 29 ;
1.2568
48
1.0517
11
1.15047
1 30 1
1.2632
49
1.0505
12
1.1560
81 ;|
1.26062
50
1.0618
13
1.1615
82 1
1 . 2762
51
1.0661
14
1.1670
1 38 1
1.2828
52
• 1.0709
15
1.1726
34 .,
1.2894
53
1.0701
1«
1.1781
i 35
1.2951
54
1.0818
17
1.1840
36
1.30i7
55
1.0865
18
1.1900
37
1.3093
56
1.0917
19
1 . 1959
38
1.8169
57
ACIDUM VALERIANICUM.
VaUrianie Acid. Isopropyl-nestic Acid,
Ger. Valeriansaure, Baldriansanre ; Fr. Acide val6rianique ;
8p. Acido valerianico.
C,H,,0, « ^{{'^Cri-CII,-CO-OH;* 102.
Pure valerianic acid forms a thin, colorless, or nearly colorless
liquid, having the persistent odor of valerian-root, and a pungent,
acid taste; it reddens litmus, bleaches the skin, and burns when
* Of the acids having the empirical formula C-HmO., four modifications are
theoretically posMhle, all of which are at pr^sfint known :
(1) Normal valerianic acid, CHj-ClI,-CH,-'JH,-CO-OH. (2) The medicinal
l!(g MANUAL OF CHEMICAL ANALYSIS.
inflamed with a bright, smoky light. In contact with water, i
jibsorbs about 20 per cent, of its weight without losinp its oily con-
si.stence, and is itself soluble in 25 parls of water at 15" G. (50° F.);
it is miscible with ammonia-water, alcohol, and ether, in all pro-
portions. Its spec. grav. is 0.93't at 15° C. (59" ¥.), and it boils
at 175° C. (iii'-' F.). The commercial acid is generally the
Iiydrale 0,H, 0, + 11,0, formed as above mentioned from the
absolute acid by the absorption of about 20 per cent, of its weight
of water, and, with reference to the old notation, waa formerly
Itnown as the trihydrated ncid, C,|,H,0j.3H0; it has the specific
gravity 0.9i5, boils at 165° C. (32y^ F.), and may be also distin-
guished from the absolute acid by its limited solubility in carbon
bisulphide. When pure concentrated valerianic acid is added to
an excess of mercuric oxide, a fine red solution of baste, uncrys-
tallizable valerianate is obtained; the same coloration is produced
by a leas concentrated acid on warming the solution, a consider-
able excess of the mercuric oxide being always maintained,
Examinatioa :
Inor'janlc salts (valerianates) may be detected bj a non-volatile
residue on the evaporation of a small quantity of the acid in a
small porcelain capanle.
Forei;/n/aUy acids will be indicated by a higher specific gravity
of the acid, and may also be recognized as follows : One gram of
the acid is weighed in a tared flask, and water, of a temperature
of from 12 to 15° C. (53.6 to 5!l-' F.), is carefully added, with
constant agitation, until the acid is just dissolved. The flask is
weighed again, and the quantity of water required for solution
must be noi less than twenty-five times the weight of the acid; in
this instance, not less than twenty -fiso grams. If the acid dis-
solves in less water, it is not pure, containing admixtures (alcohol,
acetic acid, and butyric acid), which by their greater solubility
increase that of the valerianic acid. On the other hand, the quan-
tity of water required for solution must not exceed thirty times
(30 grams) the weight of the valerianic acid, in which case it
would contain less soluble or insoluble admixtures (oaproic and
similar monatomic acids, valeric aldehyde, etc.). The presence of
valeric aldehyde, as also of amylic alcohol and amyl valerianate,
tcid, or I Bopropyl- acetic add,
CH,,
CH/
;CH-CH^CO-0tI.
CHj
:><:
■CO-OH
; and (4) Ethyl-methyl- acetic acid, ,
(3) Trinielliyl-acetic
CH,
Yh
OH,
io-OH.
TliMe acids, bowevcr, wi'li the esCFpiionorUie secnnd or medicinal acid, are
principaliy of llieorelical interpsl, h 'ini; formed for the most part by difBcult
^ynllietical metliods, aud diOer m aerially in their ptiyBic&l and Chemic*]
properties.
ACIDA. 199
may likewise be detected by neutralizing the acid with ammonia-
water, when they will either separate as an oily layer or impart
a turbidity to the liquid.
If the preceding tests leave doubt as to the purity of the acid,
or if a more conclusive examination be required, five grams
of the acid are weighed in a beaker,
and mixed with about ten grams of Fio. 83.
hot water; then from a burette, or a
graduated pipette (Fig. 83), a solution
of potassium carbonate, of 1.289 spec.
frav. (containing 29 per cent, of an-
ydrous carbonate), is added drop by
drop, until the acid is exactly neu-
tralized. The quantity by weight of
the solution of potassium carbonate
used must not exceed twice the quan-
tity of the acid ; if a greater quantity
be required, the presence of butyric,
acetic, and similar homologous acids,
is evident. When, in this test, oily
drops are separated upon the surface
of the liquid, the admixture of some
neutral oily compound is indicated.
Acetic acid may be detected by care-
fully neutralizing a small portion of
the acid with ammonia- water, and
subsequently adding a dilute solution
of ferric chloride until no further
precipitate is produced ; after the
subsidence of the amorphous reddish-
brown precipitate of ferric valerianate, the supernatant liquid
should appear colorless or nearly so; a bright red color will indi-
cate the presence of acetic acid.
Mineral acids may be detected in the aqueous solution of the
valerianic acid by adding a few drops of nitric acid, and subse-
quently testing portions of it with barium nitrate for sulphuric
aeid, and with argentic nitrate for hydrochloric acid.
OP CHBMICAL <
ACONITIKA.
ACONlTINliM.
Aeonitiin. Aconitia.
Qer. Aconitin - Fr. Aconltine ; Sp.AconiUnn.
C„H„NO„; 615.
White, amorpbous puWeriilent grains, or a white or yellowish-
white powder, which, with some difficulty, may be obtained from
its BoIutioDB in a crystalline form. It melta at 120"^ C. (S-IS* F.),
and at a higher temperature is decomposed, with the evolution of
ammonia; when strongly heated on platinum- foil, it burns with a
smoky fiame, and is finally completely dissipated.
Aconitine is soluble in 150 parts of cold water; with hot water
it becomes soil and resin-lilce, and dissolves gradually in the pro-
portion of 1 part of Quoniiine to 50 parts of boiling water, most
of the alkaloid being aeain separated on cooling; it difisolves
freely iti alcohol, ether, chloroform, ainylic alcohol, benzin, warm
benzol, and in dilute acids.
The aqueous solution possesses a feeble alkaline reaction, and
an acrid and persistent bitter tasie ; the latter being dependent,
however, upon the presence of another alkaloid, Pia-aconitine,
hiiving the formula C„H„NO„.
The solutions of aconitine in water yield with phospho-niolybdic
acid a yellowish-gray precipitate, becoming blue on the addition
of ammonia; with tannic acid, potassio- mercuric iodide, and poian-
stO'Cadmic iodide, white, amorphous precipitates; with polaasio-
bismuthic iodide an orange red precipitate, and with iodine in
potassium iodide a reddish-brown precipitate, but are not preoipi-
tuted by platinic or mercuric chlorides, or picric acid. The solu-
tions of the salts of aconitine show the same behavior towards
reagents, but are precipitated by picric acid, as also by solulions
of sodium hydrate, sodium carbonate, and ammonia-water,
Aconitine dissolves in nitric acid with but a alight yellowish
coloration; with concentrated sulphuric acid, it forms a coherent
mass, which dissolves upon agitation, with a bright yellow color,
and, at ordinary temperatures, gradually passes through brown or
reddish-brown to violet-red. When dissolved in dilate phosphoric
acid, and the solution allowed to evaporate alowly in a porcelain
capsule ou the water-bath, a iine violet color ia also produced.
When aconitine is boiled with inorganic acids or alkalies, it is
resolved into benzoic acid, and an uncrystallizable base, ficoiima:
C„H„NO„ + Kfi - C,H.O, +■ C„U^NO„
Aconitine. BeDtoicncid. Acoulne.
An alkaloid formerly occasionally met with in commerce under
the name of Alorson'/i, or Ewjlish aconitine, which dift'er.! in its
physical, chemical, and therapeutical properties from the above
ATUBR. 201
described, is now recognized as consisting wholly or in part of a
distinct body, and has received the name of Pseudaconitine or
Nepaline, C^^H^NO,,. It is derived from the Indian or Nepal
aconite, Aconitum ferox Wallich, and is distinguished from aco-
nitine by its elementary composition, its higher melting-point,
185-200"° C. (365-392^ F.), and much more sparing solubility in
water, alcohol, ether, and chloroform, requiring about 250 parts
of the latter for solution, while ordinarv aconitine is soluble
in 3 parts of chloroform. It crystallizes very readily from its
solutions in the form of colorless, rhombic octahedra, and yields
some well crystallizable salts, but does not produce the above
described reacticms of ordinary aconitine with sulphuric and phos-
f)horic acids, which, however, do also not pertain to true, crystal-
ized aconitine.
When pseudaconitine or nepaline is boiled with inorganic acids
or alkalies, it af>pear8 to be first converted by dehydration into
apo pseudaconitine^ C,jH^^NO„, which latter is afterwards split into
veratric acid and apojfsertdacojiine :
C„H«NO„ = C,H,(OH),CO-OH + C„II„NO,
■v^
.—^u
Pseudaconitine. Veratric acid. Apopseudaconine.
Commercial aconitine appears of itself not to be a definite sub-
stance, but to consist of a mixture of true crystallizable aconitine,
together with pseudaconitine, picraconitine, and their various
derivatives, aconine, pseudaconine, and possibly other amorphous
bases.
For the isolation of aconitine from complex organic mixtures,
or its sef)aration and discrimination from other alkaloids, see also
pages 108 and 109.
Ether. Ethylie Ether, Ethyl Oxide.
Ger. Aether; Fr. Ether; Sp. Eter sulfurico.
C,II,.0 =. (C,H.),0; 74.
A colorless, light, limpid, and highly refractive liquid, of a
characteristic fragrant odor, very volatile and inflammable ; it
does not redden litmus, but gradually becomes slightly acid by
the absorption of oxygen and the formation of acetic acid, from
contact with the air in imperfectly stoppered bottles. When
pure, its spec, grav., at 15.5° C. (60^ F.), is about 0.720 ; it boils at
34.9° C. (94.8° F.) under a pressure of 760 mm., and does not
solidify by exposure to the most intense cold.
The United States Pharmacopoeia provides two strengths of
202
NDAL OF CHEMICAL ANALYSIS.
r nnd pliosphorus sparingly, but bro-
intial oils, and most of the fatty and
Fio. 64.
i
ether, one of the spec. grav. 0.750, at 15" C. (59° F.), ooDt&in-
ing about 74 per cent., and lether fortior, of a spec. grar. not
exceeding 0.725 at 15° C. {o9° ¥.), or 0.716 at 25° C. (77'' F.), and
containing about 94 per cent, of etliylic ether.
Ether is mincible, in all proportions, with alcohol, carbon bisul-
phide, chloroform, benzol, benzin, and the fixed and volatile oils;
pure ether dissolves but one thousandth part of its weight of
water, but is soluble in 20 parts by weight of water at 12° C.
(53.6° F.). From its solntion in ether, the water can again be
almost wholly abstracted by contact with anhydrous potassium
carbonate, provided that the ether be pure and free from alcohol.
When completely free from alcohol and water, ether has no action
on dry tannic acid, which deliquesces to a thick, syrupy fluid in
aether fortior.
Ether dissolves sulphu:
mine, iodine, caoutchouc, t
resinous substances, freely ; it is also a solvent for a number of
alkaloids, and for some metallic salts, e.r/., mercuric, auric, platinic,
and ferric chlorides, etc.
ExaminatloD:
Alcohol and Water. — Shaken with an equal bulk of water, in a
small graduated cylinder (Fig. 84), oflicinal ether should not lose
more than from one-fifth to one-fourth, and fflther
fortior not more than from one-tenth to one-eighth,
of its volume ; otherwise an excess of one or the
other of the above is contained in the ether, which
fact wil! also be indicated by a greater specific gravity
of the ether than that above staled.
A still more accurate result of this test is obtained
when pure glycerin is employed instead of water,
whereby both water and alcohol are at the same time
abstracted ; tlie latter may then be recognized bysub-
sequent distillation from the glycerin, and the addi-
tion of a few drops of an aqueous solntion of potassium
chromatQ and sulphuric acid to the distillate, when
the green color of chromic oxide will soon appear.
In the application of the preceding test, the U. S.
Pharmacopoeia requires that 10 cubic centimeters
of ether, upon agitation with an equal volume of
glycerin, should not be reduced to less than 7.5
cubic centimeters; and that when 10 cubic centi-
meters of ajther fortior are agitated with an equal
volume of glycerin, the ether layer, when fully
separated, should measure not less than 8.6 cubic
centimeters.
The presence of water in ether may also bo detected by the
appearance of a blue coloration on the addition of a little anhy-
drous cupric sulphate, or by forming a turbid solution when the
ether is mixed with an equal volume of carbon bisulphide.
ATHBR.
208
Acids, — Neutral blue litmus-paper, when previously moistened
with water and immersed in both the ethereal and aqueous layers
in the cylinder, should remain unaltered, as also when a small
quantity of the ether is evaporated in a porcelain capsule until
reduced in volume to a few drops, and then tested with litmus-
paper ; a slight acid reaction would indicate acetic acid, and, in
crude ether, possibly sulphurous or sulphuric acid; the acic) re-
action may also be caused by traces of ethyl-sulphuric acid, which,
together with other compound ethylic or amylic ethers, or alcohols,
are also indicated when a small portion of the ether is allowed to
evaporate spontaneously in a shallow porcelain capsule ; when
the ether has entirely evaporated, the inner surface of the capsule
should be covered with a deposit of moisture, without taste or
smell, and without any oily appearance.
Table of the quantity by weight of pure Ethylic Ether contained in 100
parts by weight of Ether of different specific gravities.
Temperature 17.50 C. (63.50 F.).
Per cent. |
Per cent.
1
Per cent.
Per cent.
Specifle
of ethylic
Specific
of ethylic
1 Specific
of ethylic
Specific
of ethylio
graTitf.
ether.
grarity.
ether.
gravity.
0.7456
ether.
1
grarity.
ether.
0.7185
100
0.7310
87
74
0.7614
61
0.7198
99
0.7320
86
0.7468
78
0.7627
60
0.7206
98
0.7881
85
0.7480
72 1
0.7640
59
0.7215
97
0.7342
84
I 0.7492
71
0.7653
51
0.7224
96
0.7353
88
0.7504
70
0.7666
67
0.7238
95
0.7364
82
0.7516
69 1
0.7680
56
0.7242
94
0.7875
81
0.7528
68
0.7698
55
0.7251
93
0.7886
80
0.7540
67 '
0.7707
54
0.7260
92
0.7397
79
0.7552
66
0.7721
53
0.7270
91
0.7408
78
0.7564
65 1
0.7785
52
0.7280
90
0.7420
77
; 0.7576
64
0.7750
51
0.7290
ft9
0.7432
76
0.7588
63
0.7764
50
0.7800
88
0.7444
75
0.7601
62
0.7778
49
With the decrease and increase of temperature, the specific gravity of ether
suffers a corresponding increase or decrease, amounting for eacn degree of the
centigrade tliermometer in either direction —
For ether of a specific gravity of 0.7198 to that of 0.7831, about 0.0018
" " ** ** 0.7342 ♦♦ 0.7504, ** 0.0011
*' " " " 0.7516 *' 0.7627, '' 0.0009
" " " *' 0.7640 '» 0.7764, " 0.0008
For instance: An ether of 0.7206 spec. grav. at 17.50 C, containing 98 per
cent, ethyl oxide, win have, at 20o C., a spe<j. grav. of 0.7206— (0.0013 X 2.5)
= 0.71785, and at 150 C., a spec. i?rav. of 0.7206+ (0.0018 X 3.5) =0.72885.
. OF CUEUICAL ANALYS
JBTBJSR ACBTICna.
Ar-B(ie Ether. Ethyl Acetute.
Oer. EBBigMher; Fr. EiUer ncvtique ; Sp. filer acitico.
C.H.O, - C,H.O-0-C,H,; 88.
A' colorless, light, limpid liquid, of an agreeable, ethereal, and
fruity odor and taste ; very volatile and combustible. When
perfoutly pure, its Bpeuific gravity is 0.898 at 15° C. {59° F.) and
Its boiling point 74.3° C. {165.7° F.), but as the removal of the
last traces of alcohol is eftected with great difficulty, its 8j>eciGc
gravity naually varies from 0.900 to 0.1104 at 15'^ C. (59° F.), and
its boiling-point from 74 to 76^ C. (165.2 to 168.8° F."). Acetic
ether is miscible in all proportions with etter, alcohol, chloroform,
carbon bisulphide, ana benzol, and soluble in approximately 17
parts of water. It absorbs oxygen from the air, especially if it
contains some water, forming acetic acid ; both the water and the
acid can be removed from the ether by shaking it with exsiccated
polasaium carbonate, which will become more or less liquefied
wben these fluids are present.
ExamiuatiDE :
Its aqueous solution should afford no preci pi talc with a solution of
barium chloride {snl/ihuricaeiil); and when a portion of the ether
is all'twed to evaporate in a porcelain capsule, it should leave no
permanent residue (soilium or magnesium ucttatvx).
A^cihvl. — When shaken with an equal volume of water in a
graduated glass cylinder (Fig. 84, page 202), the ether, after sub-
siding, should not have decreased in volume more than one-tenth
to oue-cighth ; when pure glvcerine is employed instead of water,
the vohiine of both liquids should remain nearly unaltered.
Alcohol and water are also indicated in connection with the pre-
ceding teat by a lower or higher specific gravity of the ether tlian
(hat above mentioned. As acetic ether may be mixed in such
proportions with alcohol and ether that the presence of these
admixtures is not readily detected on the one hand by the deter-
mintition of the specific gravity alone, or on the other hand, by
the test with absorption by water, it is necessary in its examina-
tion to apply successively both of the above mentioned tests, by
which means the admixture may be readily detected.
.Acids. — Neutral blue litmus-paper, when previously moistenetl
with water, and immersed in both the ethereal and aqueous layers
in the cylinder, should remain unaltered, as also when a portion
of the ether is reduced to a small volume by evajwratiou in a
poreelain capsule, and then tested with litmus-paper.
IMlmatlon of Uie Ethyl Acetate oontained in Aoetlo Ether :
The quantitative estimation of acetic ether is accurately and most
conveniently accomplished volumetrically, by a process which de-
iBTHBR ACBTICUS. 205
pends upon its previous decomposition into alcohol and the acetate
of an alkaline base; the amount of alkali required to effect the
decomposition of a known and weighed amount of the ether being
subsequently determined by the estimation of the excess of alkali
employed with a standard acid.
About 3 grams of acetic ether are accurately weighed in a bot-
tle provided with a closely fitting glass stopper, and having a
capacity of at least 200 cubic centimeters; 100 cubic centimeters
of a decinormal solution of crystallized barium hydrate (contain-
ing 15.75 grams Ba(OH), -f HUfi in a liter) are then added, the
whole well mixed, and, having fastened the stopper securely by
means of twine, the mixture is heated upon the water-bath for
about two hours. The decomposition of the ether which is thus
effected is expressed by the equation :
2C,n,0,(C,H,) 4- Ba(OII), = 2C,H,0 4- Ba(C,H30,),.
Ethyl acetate. Barium hydrate. Alcohol. Barium acetate.
The bottle and its contents are finally allowed to cool, then
oi>ened%ind the liquid tested with curcuma paper, which should
indicate by its brown coloration a decided alkaline reaction, while
the odor of the acetic ether must at the same time have com*
pletely disappeared. The contents of the flask are then trans-
ferred to a beaker, the flask subsequently well rinsed with several
small portions of water, and, after the addition of a few drops of
litmus soluticm, a decinormal solution of oxalic acid (containing
0.8 grams C,H,0^ -f 2HjO in a liter) is allowed to flow into the
liquid from a burette until, with constant stirring, a permanent
red coloration appears, or preferably until a drop of the solution
brought upon curcuma paper no longer produces a brown colora-
tion. The number of cubic centimeters of oxalic acid solution
employed for neutralization, when subtracted from that of the
barium hydrate solution originally employed (100), will represent
the number of cubic centimeters of barium hydrate solution re-
quired for the decomposition of the ether, and therefrom the
amount of ethyl acetate contained in the specimen under exami-
nation or its percentage strength may be subsequently readily
calculated: one cubic centimeter of decinormal barium hydrate
solution corresponding to O.OOSS gram of ethyl acetate.
MANUAL 07 CHEMtCAL .
, SPIRITL^S RKCTIFICATU8.
Ethyl AUohol.
Get. Bpiritus, WeIng«iBl ; Fr. Alcool ; Bp. Alcohol.
C,H.O = C,n,-OU ; 46.
A colorless, limpid, neutral liquid, inflammable, and burniug
with a pale blue flame, without smoke; its spec. grav. is 0.79o at
15<* C. {59° F.) ; its boiling-point at 78.4° C. (173.1" F.) ;* it is
miscible in all proixirtions with most liquid bodies, but not with
the fatty oils, witn the exception of ricinus or castor oi), and,
next to water, is the moat extensive and important solvent, dis-
solving most of the organic acids and resins, alkaloids, and many
other bodies which are sparingly soluble in water. It replaces
water in some organic compounds (chloral alcoholate, CjHCIjO +
C,H/)), and may be substituted for the water of crystalhzalion in
aome inorganic salts; e. y., CaCl, + SC.H.O, ZnCL + 2C,H,0.
Mg(NO,), + BC,H,0, PtCl.+2C,H,0; all of which tatttr. how-
ever, are decomposed by water with the liberation of the alcohol,
and the absorption of their normal etiuivalent of water.
Anhydrous alcohol has a great attraction for water, absorbing
its vapor from the atmosphere, and abstracting the moisture from
organic substances immersed in it. In the act of dilution, a con-
traction of volume and an increase of the temperature of the
mixture take place. When ao volumes of absolute alcohol are
mixed with 45 volumes of water, tlie mixture, after cooling,
will occupy only 96.2 volumes, having therefore sufiered a con-
traction of 3.8 per cent. ; and, vice verea, an expansion of volume
takes place when diluted alcohol is mixed with water: e.'j., when
lOO volumes of alcohol, of a spec. grav. of 0,96t>, containing 29 per
cent., by volume, of absolute alcohol, are mixed with 50 volumes
of water. 153 volumes will l)e obtained.
The percentage of absolute alcoliol in ils aqueous dilutions can be
determined approximately, and with sufficient accuracy for any
practical purpose, by ascertaining its specific gravity at a known
temperalure. The specific gravity of any sample of alcohol es-
tablished will, by the aid of the following table, at once indicate
the percentage of absolute alcohol:
• The offlcioM ulcobol h«a a spec. Emv. of 0,880 »l 15.8° C. (60° P.), or
0.>JIS ai 3.10 c. (770 F. ), and contnins U per cent, by volume or 91 per cent, by
weight of nbBcilule alcohol ; the ttlliiled alculiol (Alcnliul Dlla(uin) Ijm b spec.
gnv. of 0.fl38 at 15.60 c. CbOO F.). or 0.8!l> at 25° C. OT° F.). and cflntaiaa
&8 per ceul. by volume, or 4S.5 per ceni. by weight of tbHolule alcohol.
r
ALCOHOL.
■
■
207 ■
TxBtE oftht ^uanlilff of abiohiU Alcohol, by weight a
nd by vnlumt, eon- V
tained
in 100 partt of a</afous Alrohd ojdlffrreut tpecijic gravititi. ^
TpiiipcrBlurn Ifio C. (50^ ¥.).
l«).nlma«ron..li,: ""."ffVl
inOTol«i.e
eoEMn-
«iJm«'''
SpHllO
Alcohul.
"•'"•
Ai?i;ii.
Aleoh-l.
W.l.r. '
ll.tll'
0.7P5I
100
0.00
lOO.OO
0.0348
50
.13.72
42.53
O.HWK)
BO
1.28
98. as
0.B366
49
54.70
41.59
o.eo4S
88
2.54
US. 83
0,938.'i
48
65.08
40.66
0.8088
87
3.77
95.35
0.9403
47
56.66
39.74
o.etso
Bfl
4.87
93.89
0.9431
46
57.64
38.83
0.8160
95
6.18
93.45
0.9439
45
58.61
87,90
0.8206
94
7-a2
91.00
0.9456
44
56.54
37.00
0.824a
98
8.48
88.73
O.U473'
43
80.68
30.09
0.8377
9a
9.ea
88.37
0.8490
42
01.50
35.18
0.8S1I
61
10.76
87.04
0.95(16
41
63.46
34.30
0.8M4
90
11.88
80.74
0.0532
40
63.43
83.40
0.8377
86
18.01
84.47
0.9.')38
30
64.37
S3.. 18
0.840B
88
14.12
83.28
0.0553
38
66,33
81.63
0.8440
87
15.83
81.96
0.9588
37
06.26
30.76
0.8470
86
16.32
80.72
O.05H2
30
87.20
20.88
0.8500
85
17.42
79.51
0.9,105
36
08.12
39,01
0.6530
84
18.52
78. aa
0.B607
34
09.04
28.14
o.Boeo
88
19.61
77. U9
0.903O
33
09.96
27.27
0.8388
20.68
75.91
0.9633
33
70,80
30.41
0.801B
81
21.76
74.75
0.9645
31
71,80
2.1.58
U.8644
80
22.83
78.09
0.96-17
30
73.72
24.70
0.8671
TO
23.00
73.43
0,9668
80
73.63
28.85
0.8«B8
79
24.96
71.30
0.9679
88
74.58
33.00
0.873S
77
26.08
70.10
0.9690
27
76.43
22.16
0.87.13
79
27.09
69.04
0.9700
38
76.38
81.81
0.8773
75
28.15
07.93
0.9711
35
77.83
20.47
0.8804
74
29.30
00.83
0.9721
24
78.13
16.63
O.B8»0
73
30.26
65.72
0.9781
33
79.00
18.70
o.ess.^
72
81.30
64.04
0.9741
33
79,92
17. OU
0.B880
71
92.35
63.50
0.9751
31
80.81
17.18
0.8B0S
70
88.39
U3.50
0.9761
80
81.71
16.39
o.snao
09
34.44
01.43
0.9771
19
83.00
15.46
0. 80.14
68
85.47
60 38
0.9781
18
83.50
14.03
: 0.8978
67
S6.51
59.33
0 9791
17
84,39
13.80
o.oooa
60
37.54
58.29
0.9801
16
85.29
12.68
0.9026
65
38.58
57.25
0.9813
15
86.10
13.15
0.9CM9
64
39.00
50.38
0.B82S
U
87.09
11.83
0.0073
08
40.03
55.81
0.9833
13
88.00
10.51
O.OUVS
ea
41.65
54.80
0.0844
13
88.00
6.69
0.6117
61
42.67
58.19
0.9855
11
80.80
8.87
0.9189
60
43. OH
53.20
0.9807
10
90.73
8.06
0.9161
59
44.70
61.20
0.9878
9
91,68
7.84
0.9188
S8
45.73
60. 3t
0.98iKI
8
93.54
6.43
0.9205
57
46.73
49.34
0.9902
7
93.45
5.62
0.9220
66
47.78
48.28
0.fl915
6
94.38
4.81
0.9247
55
48.74
47.39
0.9938
5
65.80
4.00
0.92(17
54
49.74
40.83
0.9943
4
66.84
8.80
0.9388
QS
50.74
45.37
0.9956
8
67.17
3.40
0.0808
52
01.74
44.41
0.8970
3
98,11
1.60
0.6338
51
53.78
48.47
0.0085
1
60.06
0.80
^ i
^^
^^^^■IH
^08 MANUAL OF CHEMICAL ANALYSIS.
Since, however, the temperature exercises a considerable ex-
panding and contracting influence Ujxtn alcohol and its dilution
with water, it is necessary to ascertain, simultaneously with the
specific gravity, also the temperature of the sample ; for this rea-
8on, the areometers (alcoholometers) coDBimcted for determining
the Bpecific gravity of alcohol are provided wilh a thermometer,
and aiftcrenccs in the temperature of the alcohol under estima-
tion may readily be corrected by calculation based upon this
rule : The number of degrees of temperature of the alcohol above
or below 15° must be multiplied by four-tenths; the product ir
then to be added to the percentage of the absolute alcohol indicnied
by the specific gravity, when the temperature of the liquid wiie
lower than 15° C,, and subtracted, when it was higher.
If. «. p., tbe spec gmv. nf h Miinple is found In be 0.9S1, nt a tempcrattire of
flOC, ilsperccnlagenfrcftlalciiLol would be, nccording to tbe preceding table, 8i
IKf cent., bj Toltime ; since. Iiowever, Ibe alcohol was n-elgbed at a tempera-
ture IW lower than tbe sinndnrd temperature of tbc above table, its specific
uravity was nccordiugly greater. Tberelore. in order to correct ibis dlffen-nce,
in bns to be mullitilied by ronv-lenlbs ; the product {^4) must be iidded lollie
)ioreertage of aicolinl (81) inferred from the Bj)ec, grav.. and tbe sum ( = 8.1)
txpresses tlie real quantity ofalcoliol in 100 parts by volume.
Examination :
Alcohol should be perfectly neutral in its action upon litmus,
wholly vaporiKable by heat, and aft'ord no coloration on iho addi-
tion of ammonia water.
Fusel oil (consisting principally of amvHc alcohol, with Iraces
of propylic, butylic, and olher alcohols, free fatty acids or
compoiTTid ethers) and aldehyde may be detected by mixing a por-
tion of the alcohol with an equal volume of pure ether, and
subsequently adding an amount of water equal to the volume
of tbe mixture; the whole is shaken, and, when subsidence has
taken place, the ethereal layer is decanted, and allowed to evapo-
rate spontaneously in a shallow porcelain capsule. After the
evaporation of the ether, the residue will give the characteristic
i>dor of fusel oil, or of any flavors indicative of a previous employ-
ment of the alcohol for the extraction of vegetable substances.
Tbe residue, if sufficient in amount, may be also further exam-
ined by bringing it into a test-tube with a few drops of water,
uubsequently adding a very small quantity of sorlium acetate,
and a few drops of concentrated sulphuric acid, and gently
warming the tnixlure; if fusel oil be present, the eharac-
teriatic odor of amyl acetate (pear essence) will be developed.
The presence of fuael oil may likewise frequently be detected by
simply pouring a few grams of alcohol upon three or four times
its volume of not water, contained in a large beaker, and causing
the mixture to flow to and fro, when, in proportion as the alcohol
evaporates, the odor of the fusel oil will become more distinct.
Aldehyde will also be further indicated by a dark coloration on
the addition of ammonia-water, or when a small portion of the
alcohol is warmed with a fragment of pure potassium hydrate; as
also by the reduction of metallic silver, on the addition of a few
drops of a solution of argentic aitrate to the alcohol, and gently
Methyl Alcohol. — Among the several methods for the detection
of methyl alcohol as an admixture in ethyl alcohol, tlie following
two are preferable: 1. About 150 cubic centimeters of the alcohol
are digested for an hour with 20 gramsof plumbic carbonate, and
filtered, the filtrate is then distilled from a water-bath, and the first
20 cubic centimeters of the distillate treated with 1 cubic centi-
meter of test-solution of potassium permanganate; the color
should not disappear within one or two minutes, otherwise methyl
alcohol is indicated. 2. Ten grams of powdered potassium bichro-
mate are dissolved, in a flask, in about 75 cubic centimeters of
water, 15 grams of concentrated sulphuric acid are then added,
and subsequently about 10 grams of the alcohol to be examined.
The flask is then connected with a condenser (Fig. 85), and, after
having been allowed to stand for about a quarter of an hour,
gentle heat is applied until about two-thirds of the liquid has
distilled over. The distillate (which will contain aldehyde and
acetic acid from the oxidation of the ethyl alcohol, and also
formic acid from the oxidation of the methyl alcohol, if the latter
were present) is then slightly .supersaturated with crystallized
sodium carbonate, and evaporated at a gentle heat, with the re-
peated addition of water, if necessary, until the odor of aldehyde
has entirely disappeared. The solution is then filtered into a
test-tube, slightly acidulated with acetic acid, a few drops of solu-
tion of argentic nitrate added, and the mixture gently warmed.
If the liquid merely darkens a little, but rcmams quite trans-
210
AL OP CHEMICAL ANALYSIS.
lucent, tbe alcohol is free from raetbyl alcobol ; bnt if a <
brown or black precipitnto of reduced silver separates, and the
test-tube, after being rinsed and filled witb water, shows upon its
interior a bright metallic mirror, which, when seen aeainat
white paper, appears brown by triinsmitted light, the alcohol is
methylated.
ALCOBOL ABTTLICIIU.
Amj/tie Alcohol. Fuiel Oil.
Ger. Amjialcniiol, Fuselol ; Fr. Alcobol nnijllque ; 9p, Alcohol mnJIico.
C,H,.0»
>Cn-CH,-CH.-OH: 88.
Amylic alcohol, as obtained by fractional distillation from fusel
oil, is a mixture of two isomeric alcohols, hiiving nearly the same
boiling-point, in consequence of which they have not yet been
perfectly separated from each other; the one deviates a ray of
polarized light to the left, the other is inactive, or possibly pos-
nesses the projierty of right-handed polarization. The mixture,
when treated with concentrated sulphuric acid, yields two isomeric
amyl-sulphuric acids, which are also distinguished from each
other by the varying solubility of their barium salts.
Pure amylic alcohol ia a colorless or nearly colorless, mobile,
oily liquid, of a strong, offensive odor, and acrid, burning taste ;
its spec. grav. is 0.818 at 15" C. (69° F.), and its boiling-point
between 132 = and 133=0. (269.6°-271.4^ F.); it solidifies at about
— 23^^ C. (—8.4° F.), When dropped upon water, it floats upon
the surface like an oil, but is soluble in about 40 parts of water ;
it is raisoible, in all proportions, with alcobol, ether, carbon bisul-
phide, chloroform, and essential and fatty oils, and dissolves iodine,
sulphur, phosphorus, camphor, and many resins. When mixed
with an equal volume of coneenlrated suiphuric acid, it forms a
violet-red mixture, from which, upon dilution with much water,
the amylic alcohol is for the most part separated unchanged ;
if the mixture, however, is allowed to stand for several hours, no
separation takes place upon dilution, in consequence of the fonna-
■ Of tlie nlFohnts poBaegsing llit^ empiriCBl fnnnulA CsH„0, elglit modiflc*-
tiuus arc thenrclically possible ; Viz., -1 piiniKry, 3 aecondaiy, knd 1 leniftry,
of which numbpr. Ave ore- uow known, viz., (wo primary: (1) Morninl
wnjlic alcohol, CH,-Ca,-Ca,-CH,-CH,-OH. (2) The comniErcial smylic
ftlcohol of the above contrlimfon. Two ueondary : (3) Isoamyllc alooliol,
r Eihyl-dimclliyl carliiiiol,
CH,-CO^H,-CHC',
(4) AmylPi
'\CH,-
And one tertiary: (.'}) Pscudoaniylic alcohol, o
CH,/^\CHrCH,.
ALOINUM. 211
tion of the above-mentioned amyl-sulphuric acid, which is soluble
in water. When amylic alcohol is heated with strong sulphuric
acid and a fragment of potassium bichromate, the odor of valeri-
anic acid is evolved. Amylic alcohol does not take fire by contact
with flame, and, when dropped on paper, does not leave a perma-
nent greasy stain.
ALOINUM.
Ahin,
Ger. Aloin ; Fr. Aloine ; 8p. Aloina.
The term aloin, although originally applied to a crystalline
principle obtained from Barbadoes aloes, has now, in view of the
discovery of allied crystalline principles in other varieties of
aloes, been extended to the entire group, which, however, with the
consideration of the distinctions in their physical and chemical
characters, have received, according to their derivation, the appel-
lations harbaloin, nataloin, and socaloin. The different varieties
of aloin are apparently isomeric, and differ from each other in
their chemical composition simply by the amount of combined
water; thus: — Nataloin, Cj^HjgO^; Barbaloin, C,gH,gOy -f H^O;
Socaloin, C,,n,,0, + 311,0.
Nataloin, C,^H„Oy, crystallizes from ethyl or methyl alcohol in
thin, brittle, rectangular scales, of a pale yellow color ; it is very
sparingly soluble in water, either hot or cold, but at 15.5° C.
(60° F.), is soluble in 60 parts of alcohol, 35 parts of methyl alco-
hol, 50 parts of acetic ether, 1236 parts of ether, and 230 parts of
absolute alcohol. By oxidation with nitric acid it affords oxalic
and picric acids, and with chromic acid it yields carbonic and
acetic acids; with chlorine or bromine no definite derivative
products have as yet been obtained.
Barbaloin, C,gII,gO^ 4- II^O, is a neutral substance, crystallizing
in tufts of small yellow prisms, which lose one molecule of water
by drying in vacuo, or by prolonged heating at 100° C. (212° F.).
It is sparingly soluble in water or in alcohol, but very freely if
either liquid be slightly warmed ; it is insoluble in ether. By
oxidation with nitric acid it yields about one-third of its weight of
chrysammic acid, C,^H^(NOj)^0^, besides aloeticacid, C,^H/NO,)^0^,
and oxalic and picric acids; with chromic acid, or a mixture of
potassium bichromate and sulphuric acid, it yields, besides car-
bonic and acetic acids, a peculiar yellow compound, aloxanthin, ot
the composition C„H,oOg, which is soluble in alkalies, forming a
cherry-red solution, and, when heated with zinc dust, yields methyl-
anthracene, C.^H^(CHj). Aloxanthin may thus be considered as
tetroxymethylanthraquinone, C,^Hj(CH3)(0H)^0,; when treated
212 MANUAL OF CHEUICAL AMALYStS.
with nitric acid, it is convened into cbrysiimmic acid. With
bromine or chlorine, barbaloin combiues to form yellow crystal-
lizable com|xHinds of brom- or chloraloin.
Socaloin, C ,T1„0, + 3H,0, forms Hmall tufted acicular prisms of
a yellow color, and is much more soluble thau nataloiu. It is
very freely soluble in methyl alcohol, and, at ordinary tempera-
tures, is soluble in 30 parts of alcohol, 9 parts of acetic ether, 380
parts of ether, and 90 parts of water. It melts at 118 to 120** C,
(242.6 to 248° F.) to a soft, mass, and parts with its water of urya-
tallization by drying over sulphuric acid. By the action of oxi-
dizing agents, potassium bichromate and sulphuric acid, or nitric
acid, it furnishes the same products as those yielded by barbaloin,
but with bromine no well-defined compound has as yet been
obtained.
Zanaioin, prepared from a variety of Socotrine aloes imported
from Zanzibar, is believed to be ideiitica! with socaloio.
DlstingnlsMns Tests :
The three varieties oF aloin, nataloiii, barbaloin, and socatoin,
may be distinguished from each other, and, to a certain extent, also
themselves identified, by the following reactions : A drop of nitric
acid, contained on a porcelain plate, produces with a few particles
of nataloiii or barbaloin a bright crimson coloration, rapidly fading
in the case of barlmloin, but permanent with nataloin, unless
heat be applied ; with socaloin but little eflect is produced. To
distinguish barbaloin from nataloin, they are separately tested
by adding a minute qnantitv to a drop or two of sulphuric acid,
on a [loreelain plate, and then allowing the vapor from a gtasa
rod, moistened with nitric acid, to pass over the surface; barba-
loin and socaloin undcrgn no change, but nataloin assumes a fine
blue color.
ALUMINII KT POTASSII SULPHAS, ALUMISII ET AMMONIl
SULPHAft.
Ger. Alaun; Fr. Aliiu; 8p. Aliinibre.
A1^{S0J, + 24H,0; 948. Al,(NIlJ,(SOJ, + 24H.O; 906.*
Colorless, transparent, octahedral crystals (Fig. 86), often ex-
hibiting the faces of a cube and dodecaiiedron, and containing 24
molecules (45.57 per cent.) of water of crystallization. On ex-
• If aluminium be nccepicd ns Irivaleni, as is Indicated by the molecnlu-
r.nmposillon of st'VFmlorKnnlc compounds, tlie composilion of ftlum ii more
enrrfclly exprpBBed by (lie fotmuln AIK (or NH,)[SU,),-f- iaH,0,
ALDMISIUM- 213
poeare to the air, the surface of the Fig. 80.
crystals becomes opaque and white,
which, however, is not due lo the loss
of water, but to the absorption of am-
mouia, and the formation of a basic
sulphate.
Alum melts in its water of crvstalli-
zation at 92° C. (197.6° F.), and loses
the whole of its water very slowly by
prolonged heating at 100° C. (212° F.)
in a current of air, much more quickly
at temperatures above 185" C. (365"
F,), swelling up to a white porous mass
(burnt alum), which, when moistened with a few drops of solu-
tion of cobaltous nitrate, and again strongly heated, assumes a
bine color.
Potassium alum, which is the official one of the U, S. and the
German PharmacopiKias, is soluble in 25.6 parts of water at 0^ C.
(32° F.), in 10.5 parts at 16=' C. (59° F.), in 6.6 parts at 20° C. (68°
F.), and in 0.27 part of boiling water : it is also soluble in glycerin,
but insoluble in alcohol, ether, and chloroform. Its s<ilution has a
sweetish, astringent taste, reddens litmus-paper, and gives with the
alkaline hydrates a voluminous white precipitate of aluminium
hydrate, which is nearly insoluble in ammonia water, but readily
soluble in an e.\cess of potassium or .sodium hydralL-s. from which
solution, however, it is again precipitated on the addition of am-
monium chloride; the alkaline carbonates and phosphates also
produce whit« precipitates of aiuminium hydrate or phosphate,
insoluble in an excess of the reagents, and with solutions of barium
salts a white precipitate of barium sulphate is produced. The
aqueous solution of alum dissolves metallic zinc, especially when
heated therewith in a platinum capsule, with the evolution of
hydrogen, and the formation of zinc sulphate and a basic salt of
ifie composition AVSO,),+ 2AUHO),+ K^O, + 3n,0.
Ammonium alum is very similar to potas-sium alum, and analo-
gous in its composition, but differs therefrom in some of its
chemical and physical properties. Its specific gravity is 1.626,
whilst that of pola8.sium alum is 1.724. It is soluble in 19.3 parts
of water at 0° C. (32° F.), in 7.4 parts at 20° C. (68° F.), and in
0.24 part of boiling water; itfl relations to other solvents and re-
agents being similar to those of potassium alum.
Commercial alum frequently contains both ammonium and po-
tassium in varying proportions, the former being substituted, to
a greater or leas extent, for the latter ; since their properties are
nearly the same, this admixture is of little consequence in the
common uses of alum. Potassium alum consists, in 100 parts, of
18.3.3 parts of potassium sulphate, 36.14 parts of aluminium sul-
phate, and 45.57 parts of water of crystallization; while ammo-
nium alum contam.s, in 100 parts, 14.55 of ammonium sulphate,
214
UASUAL OF CBE
ICAL ANALVSrS.
37.82 of aluminium aulplmte, and 47.63 of water of crystallization.
The [iresence of ammonium alum is recognized by the odor of
ammonia, and by its reaction upon moistened red test-paper, as
also by the formation of white fumes when a glass rod, moistened
with acetic acid, is held over the mouth of the test-tube in which
n little of the powdered alum is heated with a solution of potas-
sium hydrate,
Euminatiim:
Iron is recognized in the solution of alum, after the addition of
u few drops of sulphuric acid, by a blue coloration when tested
with potassium fcrrocyanide; most crude alum contains traces of
ferric salts; their quantity, however, should not be so consider-
able as to produce a purple coloration of a solution of the alum
upon the addition of a few drops of solution of tannic acid, or
more than u bluish coloration when one drop of test-solution of
potassium ferrocyanide is added to a sohition of 1 gram of alum
in 30 cubic centimeters of water.
Other melatlic impurities may be detected in the solution, after
the addition of a little tartaric acid and subsequent supersatura-
tion with ammonia- water, by hydrogen sulphide or ammonium
sulphide; a dark coloration or precipitate indicates metallic im-
purities ; a white precipitate, not disappearing up<m the addition
of potassium hydrate, would show zinc. If required, the natare
of such a precipitate may be determined by the method described
on pages 62 to 59.
Seteotion of Alum in Floor or In Bread:
From r>() to ion grnms of the substance to bo examined are
digested in a flask or porcelain capsule, at a gentle heat, with
concentrated nitric acid, or with concentrated hydrochloric acid
and a little potassium chlorate, until the organic substances are
completely destroyed, and a limpid slightly yellowish solutionis
obtained. The liquid is then diluted with water, filtered, evapo-
rated to a small volume, potassium hydrate (free from alumi-
nium) in slight excess adaed, and the liquid afterward acid-
ulated with hydrochloric acid, and finally supersaturated with
ammonia-water; if a transparent, flucculcnt precipitate is thas
produced, it will indicate a salt of aluminium, or alum.
ALUMinil HTDRAS.
ALUMINIUM IITDRICUM, ALUMINA HYDRATA.
Eydrale of Aluminium. Aluminium Jlydrale. Hgdrated Alumina.
Oer. Tlionerdebydnt ; Fr, Hydrate d'nliitnlue ; Sp. Ilydnito de aldmlna.
AIv;OH),; 156.
A white, amorphous, inodorous, and tasteless powder, neutral in
its action upon litmus, and jiermanent in the air. It is insoluble iu
• ALUMINIUM. 215
water, either hot or cold, but soluble in acetic and the dilute mineral
acids, particularly upon warming, and is also dissolved by solu-
tions of potassium or sodium hydrate, but is insoluble in ammo-
nia-water. Its solution in the fixed alkaline hydrates is not
rendered turbid by boiling, but it is separated therefrom as a
transparent flocculent precipitate, on the addition of a solution of
ammonium chloride. When a small portion of aluminium hydrate,
contained on the looped end of a platinum-wire, is moistened with
a drop of a solution of cobaltous nitrate, and strongly heated, a
beautiful blue color will be imparted to the bead.
One hundred parts of aluminium hydrate, when strongly heated
in a weighed porcelain crucible, until after cooling and repeated
weighing the weight remains constant, should afford a residue of
aluminium oxide Al^O,, weighing 65.4 parts.
Examination :
Soluble salts in general may be detected by boiling a portion of
the powder with about twenty times its weight of water, filtering,
and evaporating the filtrate to dryness. If a residue is obtainea,
it is dissolved in water, and acidulated with a few drops of nitric
acid ; effervescence will indicate carbonates. The solution is then
tested, in separate portions, with argentic nitrate for chlorides^ and
with barium chloride for sulphates^ when a white precipitate in
either case will reveal the presence of such impurities.
Barium^ calcium^ and zinc^ when in the form of soluble salts or
carbonates, may be detected by dissolving a portion of the powder
in acetic acid, with the aid of a gentle heat, and testing the solution,
in separate portions, as follows : To a portion of the solution, solu-
tion of potassium chromate is added, when a yellow precipitate will
indicate barium, or possibly lead ; after filtration, if necessary, solu-
tion of ammonium oxalate is added, when an ensuing white pre-
cipitate will indicate calcium. To another portion of the acetic
solution ammonia-water in considerable excess is added, the mix-
ture filtered, and tested with ammonium sulphide, when an ensuing
white precipitate will indicate zinc.
Silica and insoluble sulphates will be indicated by an insoluble
residue when a portion of the powder is treated with warm dilute
hydrochloric acid. Such a residue may be further tested by mix-
ing it with about three times its weight of exsiccated sodium
carbonate, and fusing in a small porcelain crucible ; the fused mass
is then treated with warm water, filtered, the filtrate acidulated
with hydrochloric acid, and tested with barium chloride, when a
white precipitate will indicate sulphates. The portion of the fused
mass insoluble in water is supersaturated with acetic acid, the
solution evaporated to dryness by the aid of a gentle heat, and the
residue dissolved in water acidulated with acetic acid, when silica
will remain behind as an insoluble powder; the clear solution is
then tested, in separate portions, with ammonium oxalate for cal-
cium, and with sulphuric acid for barium.
216
MANUAL OF CBBMICAL ANALVBI6.
ifelallic i'mpuriliea may be Jetected by Jissolviug a portion of
the alummium hydrate in dilute hydrochloric acid, and tenting
with hydrogen sulphide; a dark coloration or precipitate will
indicate copper or lead.
Another portion of the dilute acid solution may be subse-
quently tested with a drop of solmiuii of potaasiuin ferrocyanide,
when an ensuing blue coloration or precipitate will reveal the
presence of ir-n.
ALTTMINII STTLFHAS.
ALUMINIUM SULFURICUM.
SalphaU of Atumiiiium. Aluminium SiitphaU.
<ier. ScliwcfeleHures Alumiuiuro; Fr. Sulfate d'alumiDe; Sp.Salfalodc alumina.
A1,(S0.), + 18H,0; 666.
A white crystalline powder, or small pearly, aix-eided, mono-
clinic tablets, ijermanent in the air, and containing 18 molecules (48.6
percent.)of water of crystallization. When exposed to heal, it first
melts ill its water of crystallization, which it loses at about 200° C.
(392° F.), swelling up to a light, porous mass of anhydrous salt,
which dissolves but slowly again in water. At a red heat it is
decomposed with the liberation of sulphuric acid, leaving behind
aluminium oxide (alumina or argilla), which, when moistened with
solution of coballous nitrate and reheated, assumes a blue color.
Aluminium sulphate is soluble in 1.2 jiarts of water at 15" C.
(51)° F.), and very soluble in boiling water, but is almost insoluble
in alcohol. Its aqueous solution possesses an acid reaction and
an astringent taste, and yields a white precipitate with barium
chloride, insoluble in hydrochloric acid ; with the alkaline hydrates
it also yields a voluminous white precipitate, of which that with
the fixed hydrates is soluble in an excess of ihe precipitant
(evidence of the absence of magnesium), but is precipitated again
upon the addition of ammonium chloride. The alkaline solution
should yield no reaction u]x>n the addition of a few drops of ammo-
nium sulphide; the occurrence of a brown or yellowish-red pre-
cipitate would indicate /erne and mari'janic salts, and of a wnite
one zinc.
The presence of salu of ike alkalies may be detected by adding
to a solution of the salt a slight excess of ammonia-water, heating
until the odor of ammonia has disappeared, filtoriug, evaporating
the filtrate to dryness, and igniting the residue at a gentle heat;
no fixed residue, or but a very slight one, not exceeding 5 per
cent, of the weight of the salt, should remain.
AMMONIUM. 217
AMMONn BBNZOA8.
AMMONIUM BENZOICUM.
Bemoate of Ammonium, Ammonium Bemoate.
Qer. Benzoesaures Ammonium ; Fr. Benzoate d^ammoniaque ;
Sp. Benzoato de amoniaco.
NH,C,H,0, « C,H,-CO-ONH, ; 139.
Small, colorless, shining, thin, four-sided, tabular crystals, per-
manent in the air, and having a feeble odor of benzoic acid, and a
saline, somewhat balsamic, and bitterish taste. When heated to
120° C. (248° F.), the salt melts; at 239° C. (462.2° F.) it boils,
but becomes thereby partially decomposed, with the elimination
of two molecules of water, and the formation of benzo-nitrile
(phenyl cyanide), C,H^-CN, a colorless, limpid liquid, having an
odor resembling that of bitter-almond oil ; when strongly heated
on platinum-foil, the salt first fuses, emits vapors having the
odor of ammonia and of benzoic acid, and is finally completely
dissipated.
Ammonium benzoate is soluble in 5 parts of cold, or 1.2 parts
of boiling water; in 28 parts of cold, or 7.6 parts of boiling alco-
hol; and is also soluble in glycerin. Its aqueous solution loses
ammonia upon evaporation, and is converted into the more spar-
ingly soluble acid salt, NH^C,H,Oj -f CyHgO,: if not too dilute, it
emits the odor of ammonia when heated with potassium hydrate,
and gives a white precipitate of benzoic acid upon the addition of
hydrochloric acid, and a copious, pale, reddish-yellow precipitate
of basic ferric benzoate with ferric salts. The diluted solution of
ammonium benzoate must remain clear when mixed with lime-
water (evidence of the absence of ammonium oxalate), and, when
acidulated with nitric acid, should afford no turbidity or precipi-
tate on the addition of a solution of barium chloride (absence of
sulphates), or with argentic nitrate (absence of chlorides).
AMMONn BROMIDUM.
AMMONIUM BROMATUM.
Bromide of Ammonium, Ammonium Bromide,
Ger. Bromammonium ; Fr. Bromure d^ammonium ; Sp. Bromuro de amoDio.
NH,Br; 97.8.
Colorless, transparent, anhydrous, prismatic crystals, or a white,
granular salt, which, by exposure to the air, gradually assumes a
yellow color, from the liberation of a minute quantity of free
218
MANCAL OF CHEMICAL i
bromine. Wlicn strongly heated, the salt is completely volatil-
ized, witUoiit decomiKiBition or charring.
Ammonium bromide is soluble in 1.5 parts of water and in 150
parts of alcohol at 15" C. (50° F.), in 0.7 part of boiling water
and in 15 parts of boiling alcohol, and very sparingly soluble in
ether. Its aqueous solution liaa a saline, pungent taste, is neutral
to test-paper, and, when acidulated with a few drops of nitric acid,
yields on the addition of a solulioa of argentic nitrate a yellowish
cnrdy precipitate of argentic bromide, which is sparingly soluble
in ammonia-water ; when the aqueous solution is added to a very
dilute solution of mercuric chloride, no precipitate is produced
(distinction from alkaline iodide). An aqneou." solution of the
salt, mixed witli a little mucilage of starch, and a few drops of
chlorine- water subsequently added, produces a yellowish-brown
coloration, without exhibiting a blue tint (absence of iodide).
Heated with potassium hydrate, it emits the odor of ammonia.
SExamJnatioii :
Ammonivm bromate is detected in the aqueous solution by a
yellow coloration on the addition of a few drops of dilute sul-
phuric or nitric acid, due to the liberation of bromine, which is
rendered more evident by subsequent agitation with a few drops
of carbon bisulphide or chloroform.
Ammonium chloriiie, or other alkaline clilorides, when present
in any considerable amount, may be detected bv precipitating the
aqueous solution with argentic nitrate, and digesting the moist,
well-washed precipitate with a cold, saturated solution of ammo-
nium carbonate. After standing for some time, the solution is
filtered, and the filtrate sui>er saturated with nitric acid; if the
bromide is pure, but a slight turbidity will occur, whereas, if
chlorides are present, a white, curdy precipitate will be jiroduced.
In order to ascertain, in this case, the presence of not more than
three per cent, of chlorides, three grams of the dry salt are dis-
solved in so much distilled water as to make the solution mea-
sure 100 cubic centimeters. Then to 10 cubic centimeters of this
solution a few drops of test-solution of potassium bichromate
are added, and subsequently, with constant stirring, standard solu-
tion of argentic nitrate ; not more than 31,4 cubic centimeters of
the latter should be required, before the red color ceases to dis-
appear, otherwise the salt contains more than three per cent, of
chlorides.
Smaller quantities of chloride may be detected by mixing 5
grams of the powdered and well-dried salt with (J grams of pure
powdered potassium bichromate, bringing the mixture into a small,
perfectly dry flask, which is connected with a receiver containing
a small amount of water (Fig. 87), and subsequently adding to the
mixture in the flask 15 parts of pure concentrated sulphuric acid;
the reaction being finally aided by the application of a gentle heat.
If chlorides are present, chloro-uhromic anbydride, CrO,Cl^ will
AHMONtUM.
be volatilized, and may be subsequently recognized in the distil-
late, after neutralization with ammonia- water, by the yellow color
of the solution, and by the application of the several reactions for
chromates; or, by its reduction to green chromic oxide, on the
addition of a little hydrochloric acid and alcohol, and gently
warming.
Nitrates will be indicated in the aqueous solution of the salt by
a brown coloration, when a little dilute sulphuric acid is added,
and the mixture heated to boiling. The presence of nitrates may,
however, be more conclusively established by precipitating an
aqueous solution of the salt with plumbic acetate, or preferably
argentic acetate, in slight excess, filtering from the precipitate of
plumbic or argentic bromide, and subsequently adding to the fil-
trate a solution of ferrous sulphate, and afterward concentrated
sulphuric acid, so as to form two layers (Fig. 88); a brown or
purplish zone at the line of contact of the two liquids will reveal
the presence of nitrates.
Sulphates may be detected in a solution of 1 part of the salt in
about 20 parts of water, by a white turbidity or precipitate on the
addition of a few drops of solution of barium chloride.
Estimation:
One part of the ijry salt, when completely precipitated by ar-
gentic nitrate, yields, if perfectly pure, 1.917 parts of argentic
bromide. Upon the relation of the amount of argentic nitrate
required to completely precipitate a definite amount of the salt,
the following volumetric meth<xl of estimation ia based: Two
grams of ammonium bromide, previously reduced to powder, and
carefully dried, are dissolved in water to the measure of 100 cubic
centimeters ; 10 cubic centimeters of this solution, corresponding
220
ANDAL OP nlEMtCAL ANALYSIS.
to 0.2 gifirn of ammonium bromide, are then brought into a
beaker, diluted with about 50 cubic centimeters of water, and,
sftor the addition of a few drops of a solution of potassium chro-
mate, a docinormal solution of argentic nitrate (page 98) is allowed
to flow into the lirjuid from a burette until, with constant stirring,
11 permanent reddish-brown coloration is produced. If the salt is
pure ammonium bromide, 20.41 cubic centimeters of the silver
solution will be required to produce this eft'ect, as containing 0.347
gram of argentic nitrate, which corresponds to 0.2 gram of am-
monium bromide, according to the equation;
AgNO.: NH,Br = 0.347 : 0.2.
170 98
If the salt were pure ammonium chloride, 37.35 cubic centime-
ters of the silver solution would be ret^uired, in accordance with
a similar proportion ; the dift'erence in the amount of silver solu-
tion required for 0.2 gram of the two salts, would, therefore, be
37.35 — 20.41 — 16.94 cubic centimeters ; from which it follows,
that for each 0,1(594 cubiu centimeter of silver solution required in
excess of 20.41 cubic centimeters, in order to effect complete pre-
cipitation, 1 per cent, of ammonium chloride will be represented,
as 'fj^* ^ 0.1694. It is evident, that the presence of ammonium
iodide, or other alkaline chlorides or bromides, would influeoae
the result in proportion to the quantity of the admixture.
A U MOM DM.
AHMONII CASBONAS.
AMMONIUM CARBONICUM.
Carbonate ef Amttumiuta. Ammonivm Stigui-earbamtla,
NJT„C,0. - NH,HCO,+ NH,NH,CO,; 157.
Colorlefs, hjird, translucent, crystalline roaascs, conHiating of
equal molecules of acid ammonium carbonate and uarbamate. It
possesses a pungent ammoniacal odor, free from enipyreutna, a
sliarp saline taste, and an alkaline reaction, and, wlieii strongly
heated, is completely volatilized without fusion. When exposed
to the air the salt decomposes rapidly, becoming opaque, with
the liberation of both carbonic acid gns and ammonia, and is
converted into a white, crystalline powder of aoid ammonium
carbonate (bicarbonate).
Ammonium carbonate is soluble in 4 parts of water at 15° C.
^59° F.), and in l.o parts at tiO" C. (149° F.); it is also soluble
in about 5 parts of glycerin, and is freely dissolved by dilute acids,
with the liberation of carbonic acid gas. In contact with alcohol,
the salt is resolved into ammonium carbonate, which dissolves,
whilst the acid carbonate remains behind ; the latier salt is solu-
ble, however, in about 8 parts of water at 15- C. (59^ F.). The
a.'ijueous solution of the salt, when heated to 47° C. (116.6° F.).
becomes partially decomposed, with the lilieration of carbonic
acid gas ; thia decomposition take-s place more rapidly at 75° C,
(167" F.), and at temperatures above 85° C. (ISS'^ F.) much am-
iiionia is also evolved, so that by prolonged boiling the salt is
completely decomposed and dissipated, and the solution upon
evaiioration leaves no residue.
uamlnatioD:
Acid amn'oiiium carbottale (bicarbonate) will be indicated by
the change from the hard crystalline state of the salt to the friable
pulverulent condition, by the much less pungent ammoniaoKl
odor, and by the more sparing solubility of the salt in water, and
insolubility in alcohol, as al>ove mentioned.
Ammonium sulphate is detected in the aqueous solution, pre-
viously acidulated with nitric acid, by a white precipitate on the
addition of barium chloride.
Amtnonimn chloride and hyposnlphile are recognized in the
aqueous solution, previously neutralized with acetic acid, by test-
ing it with argentic nitrate; a white precipitate, inaoluote in
diUtted nitric acid, will indicate chloride ; a white turbidity, which
gradually turns black, indicates hyposulphite.
Calcixim salts will be detected in the aqueous solution, acidu-
lated with acetic acid, by a white precipitate on the addition of
222 Manual of cukmical analysis.
ammonium oxalate, and will also remain behind when a little of
the ammonium carbonate is Htron^ily heet«d on platinum fail.
Metallic impurities are detected in the aqneoua solution, pre-
viously acidulated with hydrochloric acid, by the successive ap-
plication of hydrogen sulphide aud ammonium sulphide, accord-
ing to the aystematic method of analysis, as described on pages
51 to 61, with apecial consideration of the possible presence of
arsenic, lead, copper, and iron.
Evipyrenvialic avlsiances may be detected in the solution of 1
Sart of the salt in about 20 parts of water, supersaturated with
iluted sulphuric acid, by the adilition of a few drops of solution
of potassium permanganate ; after standing for about five minutes
at the ordinary temperature, no perceptible change of color
should ensue, otherwise the above mentioned impurities will be
indicated.
EstimatioQ:
The purity of the salt may be approximate! 7 determined by
ihe amount of tartaric or citric acid required for its neutraliza-
tion: one part of ammonium carbonate requiring for exact neu-
tralization 1.33 parts of citric, or 1.43 parts of tartaric, acid. Its
quantitative estimation may, however, be more conveniently and
accurately accomplished volumetrically. Two grams of the salt
are dissolved, in u beaker, in about 20 cubic centimeters of cold
water, a few drops of litmus solution added, and a normal solu-
tion of oxalic or sulphuric acid (page !I2) subsequently allowed
to flow into the liquid from a burette until an excess of acid has
been employed, and the liquid assumes a permanent, bright
cherry-red color; after having been healed to boiling, in order
to completely ex].iel the liberated carbonic acid gas, a solution of
normal alkali (page 87) is added to the liquid from a burette,
until, with constant stirring, a permanent blue tint is produced.
The number of cubic centimeters of acid solution required for
the exact neutralization of the salt having thus been determined,
its purity or percentage strength may be readily calculated : one
cubic centimeter of normal acid corresponding to 0,0523 gram of
pure ammonium carbonate. By the employment of 2.til5 grama
of the salt, and a strictly normal acid solution, the number of
cubic centimeters of the latter required for neutralization, when
multiplied by 2, will represent at once the perceulage purity of
the salt.
L
Tim hook is thepro^.
COOPER MEDICAL COLL.-viw.
BAN FRANCISCO. OAL
nt^ M not to ''f r-"-;" ■' d j' "?t the
Idbrari/ Aw>'* l-j v- t.ft't^iKt or
under at.i/;^c?('-x/ w-':i:i.'r,-
AU»ONIt)M.
AMMONII CBLORIDTTM.
AMMONII MtmiAS. AMMONIUM CnLUBATUM.
SAL AMMONIACUM.
OMoridt of Amfaonium. Ammonium Chloride. iSal Ammoniae,
Ger. Clilorainmoniam; Fr. Chlorure d'nminonlum ; Sp. Clomro de amoniftco.
NH.Cl; 53.4.
A colorless, anhydrous salt, either in transluceiit, cryBtalline
masses, of a tough, fibrous texture, or a granular white powder,
or, as obtained by cryHtallization from its saturated aqueous solu-
tion, feather-like growths, consisting of an aggregation of small,
regular octahedral or cubical cryatals,
or combinations of such, which often '■
exhibit trapezohedric hemidedry, and
thus appear to belong to the hexa-
gonal or quadratic system {Fig. 89).
The salt has the specific gravity of
1.52. It is permanent in a dry atmos-
phere and at ordinary temperatures;
whenstronglyheated, it volatilizes with-
out fusion or charring, forming dense,
white fumes, and suffers thereby a
partial dissociation into ammonia and
hydrochloric acid gasea, which, how-
ever, again combine upon condensation in Ihe for
crystalline powder of the original salt.
Ammonium chloride is soluble in 3.5 parts of water at 0'^ C.
{32° F.), in 2.85 parta at 16.5° C. (60° F.), and in 1,37 parts of
boiling water; it is also soluble in about 6 parts of glycerin, but
only sparingly in alcohol, and not at all in ether or chloroform.
Its aqueous solution has a sharp, saline taste, a slightly acid reac-
tion, and becomes partially decomposed on boiling, with the loss
of ammonia; it emits the odor of ammonia when heated with a
solution of potassium or sodium hydrate, and yields with argentic
nitrate a curdy, white precipitate, which is insoluble in nitric acid,
but soluble in ammonia-wntor.
Examinatloii :
Sulphates are detected in the diluted solution, acidulated with
hydrochloric acid, by a white precipitate, when tested with barium
nitrate.
Fi^ixd {vtpuriiics arc indicated by a residue left after complete
volatilization of the ammonium chloride, upon platinum-foil, or
in a porcelain crucible.
Metallic impurities may be detected in the aqueous solution,
previously acidulated with hydrochloric -scid, by a coloration or
precipitate when tested successively >v;ith hydrogen sulphide and
, of » light
224
MANUAL OF CHEMICAL .
ammonium sulphide, A precipitate thus obtained may be further
examined or identified according to the systematic methods of
analysis, as described on pages 61 to 61.
Iron may also be recognized at once by a blue coloration, when
the solution of the salt is acidulated with hydrochloric acid, and
tested with potassium ferrocyanide.
Ammonium sulpiwfyanide and barium saltx haviue been occa-
sionally delected as a contamination of ammonium cTiioride, they
may be tested for as follows : The sulphocyanide may be extracted
by digestion with hot alcohol, and, after the evaporation of the
alcohol, and dissolving the residue in a small quantity of water,
will be recognized by a blood-red color on the addition of a few
drops of solution of ferric chloride. Soluble barium salts will be
recognized in the aqueous solution by a while precipitate on the
addition of a few drops of dilute sulphuric acid. In the presence
of lead, which would likewise be precipitated by the sulphuric
acid, the two precipitates may be diBtinguished by the solubility
of ihe lead sulphaie in basic ammonium tartrate, whereas the
lead will have been also detected in the previously applied tesls
for metals, with hydrogen sulphide.
Estimation:
One grain of the powdered and dry salt, when completely precipi-
lated by argentic nitrate, yields a precipitate of argentic chloride,
which, when washed, and dried, should weigh 2.6ti2 grams. Its
purity, when free from other chlorides, may be also conveniently
and accurately determined volumetrically by dissolving 0,2 gram
of the powdered and dry salt, in a beaker, in about 20 cubic cen-
timeters of water, and, after the addition of a few drops of a
solution of potassium chromate, allowing a decinormal aoluiion of
argeniic nitrate (page 98) to flow into the liquid from a burette
until, with constant stirring, the red coloration of argentic chro-
mate remains permanent. The number of cubic centimeters of
the silver solution which are required to produce this eftect, when
multiplied by the decimal 0.00535, will represent the amount of
pure ammonium chloride in the quantity under estimation. Bv
the employment of exactly 0,2t)75 gram of the salt, and proceed-
ing as above, the number of cubic centimeters of the silver solu-
tion required to efl'ecl complete precipitation, multiplied by 2,
will indicate at once the percentage amount of pure ammonium
chloride.
i
i
AMMONIUM. 225
AMMONII lODIDUM.
AMMONIUM lODATUM.
Iodide of Ammonium, Ammonium Iodide.
Ger. Jodammoiiium ; Fr. lodure d^ammontuin ; Sp. loduro de amonio.
NH,I; 144.6.
A white, granular, and deliquescent salt, crystallizing in cubes,
which, when exposed to the air, becomes yellow or yellowish-
brown, from oxidation and consequent liberation of a minute
quantity of iodine. When heated, it is completely volatilized
with the evolution of purple vapors.
Ammonium iodide is soluble in 1 part of cold, and 0.5 part of
boiling, water ; and in 9 parts of cold, or 3.7 parts of boiling, alco-
hol (distinction from ammonium and potassium bromides, which
are less soluble in alcohol). Its aqueous solution has a pungent,
saline taste, and emits the odor of ammonia when heated with a
solution of sodium or potassium hydrate; it yields with mercuric
chloride a red precipitate, soluble in an excess of either the
ammonium or mercuric salt; and with argentic nitrate, a yellow-
ish-white precipitate, which remains unchanged upon the addition
of dilute nitric acid or ammonia-water; the solution assumes a
blue color upon the addition of mucilage of starch and a little
chlorine-water.
Examination :
An admixture of alkaline iodides, bromides, or chlorides, is
approximately recognized, when a concentrated aqueous solution
of the salt is dropped into strong alcohol ; the liquid must remain
clear; the separation of a white crystalline powder would indicate
such an admixture.
Chlorides and bromides are detected by completely precipitating
the solution of the salt with argentic nitrate, subsequently digest-
ing the precipitate with ammonia-water, and filtering; the filtrate
is then supersaturated with nitric acid, when a slight turbidity
may ensue; a white precipitate would indicate chlorides and
bromides. In this case, and in order to distinguish argentic
chloride or bromide, the precipitate is collected and washed upon
a filter, and is then rinsed through the pierced filter into a test-
tube; the supernatant water is decanted as far as practicable, and
good chlorine- water is poured upon and agitated with the silver
salt. This will remain unchanged if it consists of argentic chloride,
but, if it contains argentic bromide, the chlorine-water assumes a
yellowish or reddish color, due to the elimination of free bromine,
which will be absorbed by chloroform when agitated with that
liquid.
Sulphates may be detected in the diluted solution, acidulated
15
226
MANUAL OP CHEMICAL ASALVfllS.
witli livtirocliloric acid, by a wiiite precipitate oa the addition g
a few lirops of a solution of barium chloride.
Estimation :
One part of the salt, in aqueous solution, wheu completely pre-
cipitated by argentic nitrate, yields a precipitate of argentic iodide,
wliieh. when washed and dried, should weigh 1.62 parte. The
flurity of the Halt may also be determined vol u metrically as fol-
owa: 0.2 gram of the perfeclly dry salt is dissolved in a beaker
in about 50 cubic centimeters of water, a few drops of neutral
potas-sium chromate solution are then added, and subsequently a
decinormal solution of argentic nitrate (page 98) is allowed to flow
into the liquid from a burette until, with conntant stirring, a per-
manent red coloration is produced. If the salt is pure ammonium
iodide, 18.76 cubic centimeters of the silver solution will be re-
quired to effect its complete precipitation ; one cubic centimeter
of the decinormal silver solution corresponding to 0.0145 gram
of ammonium iodide. If ammonium bromide or chloride is pres-
ent, the number of cubic centimeters of silver solution required
for precipitation will be larger in proportion to the extent of the
admixture.
AMMONII NITRAB.
AMMUNIUM NITRICUM.
' of Ammoninm. JuinonlUfn Sil\
Ammonium ; Fr. Air
d'ammonlaque ; Sp. Nitrato de
NH.NO,; 80.
Long, flexible, colorless needles, or a tibrous crystalline mas.^;,
when obtained by crystallization at temperatures above 40-^0.
(104" F.); and large six-sided, rboinbtc prisms,
Flo. oO. terminated by six-sided pyramids (Fig. 90), when
torystallized at a temperature below 38° C.
(100.4° F.). The salt has the specific gravity of
1.7; it is anhydrous, and quite permanent in a
dry atmosphere, but deliquesces in a moist one,
losing a portion of its ammonia, and acquiring
an acid reaction. When perfectly dry, and grad-
ually heated, it fuses at lt55-l«fi' C. (329-331*>
F.) ; and at about 185" C. (305" F.) it is resolved
into aqueous vapor and nitro^^on monoxide (ni-
trous oxide gas), without leaving any fixed resi-
due :
NH.NO, - 2H,0 -t- N,0.
When thrown upon a red-hot surface, it be-
AMMONIUM. 227
comes decomposed, with the production of a yellow flame and a
slight explosion, into nitrogen, water, and nitric oxide ; and when
heated with concentrated sulphuric acid, it emits nitrous vapors.
Ammonium nitrate dissolves in about half its weight of water
at ordinary temperatures, a considerable reduction of temperature
being produced; it is freely soluble in hot water, and is also solu-
ble in 20 parts of cold, or 3 parts of boiling, alcohol, so that its
concentrated aqueous solution remains perfectly limpid upon the
addition of strong alcohol. Its aqueous solution has a sharp,
bitter taste ; it emits the odor of ammonia, when heated with a
solution of potassium or sodium hydrate; and when mixed with a
few drops of a solution of ferrous sulphate, and carefully poured
upon concentrated sulphuric acid, it affords a dark zone at the
junction of the liquids, characteristic of the oxides of nitrogen.
Examination :
Ammonium chloride and sulphate may be detected by white pre-
cipitates, when the dilute aqueous solution of the salt is acidulated
with nitric acid and tested in separate portions, with argentic
nitrate for the former salt, and witu barium nitrate for the latter.
Fixed impurities will be recognized by a non-volatile residue, on
strongly heating a small quantity of the salt upon platinum-foil.
AMMONII PH08PHA8.
AMMONIUM PIIOSPHORICUM.
Phoiphate of Ammonium, Trihanic Ammonium Phosphate, Diammonio-
hydric Phosphate.
Ger. Phospliorsaures Ammonium ; Fr. Phosphate d'ammoniaquc ; Sp. Fosfato
de amoniaco.
(NHJ.HPO,; 132.
Transparent, colorless, monoclinic prisms, having the specific
gravity of 1.64. They are efflorescent in dry air, and on exposure
to a moist atmosphere readily lose ammonia. When heated upon
platinum-foil, the salt first fuses, and is resolved into metaphos-
phoric acid, with the liberation of water and ammonia, and, at a
bright red heat, is wholly dissipated. When heated with a solu-
tion of potassium or sodium hydrate, ammonia gas is evolved.
Ammonium phosphate is soluble in 4 parts of water at 15.5° C.
(60° F.), with ensuing reduction of temperature, and soluble in
0.5 part of boiling water, but is insoluble in alcohol. The
aqueous solution of the salt possesses a cooling, saline taste, and a
slightly alkaline reaction, but. when the salt has been exposed to
the air or is old, the solution is neutral, or even acid, a change
resulting from the loss of ammonia and the formation of the
228 MANtTAL OP CHEMICAL ANALYalB,
priinarv monoaminoiiium jiTiospliate Nil H PO^, wtiich takes pi
more ropitlly when the solution of the salt is boiled.
With solution of argentic nitrate, the diluted solution of !im-
tnonium phosphate gives a yellow precipitate of argentic phos-
phate, soluble in ammonia-water or in nitric acid ; and with
solution of ammonium molvbdate, acidulated with nitric acid, it
yields, on warming, a yellow crystalline precipitate of ammonium
phosplio-molybdate. The solution of the salt should produce no
coloration or nrecipitata with ammonium sulphide, and, after
ncidulalion with diluted hydrochloric acid, none with hydrogen
sulphide or with barium chloride. A coloration or precipitate
with the first two reagents would indicate mftal3,a white precipi-
tate with the latter reagent, insoluble in diluted nitric acid, would
indicate »vlpliatf.
If a solution of one gram of ammonium phosphate is completely
precipitated with magnesium mixture, the precipitate collecteli
and washed upon a filter with a mixture of one part of ammonia-
water and three parts of water, dried, and subsequently heated to
redness in a tared porcelain crucible, the residue of magnesium
pyrophosphate obtained should weigh 0.841 gram.
AMMONII SULPHAS.
AMMONirM Sl'LFUItlCUM.
^nlphtitt of Amiuaiiiiim. Amiitoniim Si
Ger. Bcliwefelsfturpa Amtni
(NHJ^O.; 132.
A granular powder, or large, transparent, colorless crystals,
belonging to the rhombic system (Fig. 91), permanent in the air,
and having the specific gravity of 1.77. The salt melts at 140°
C. (284" F.) with the development of
Fir.,91, ammoniacal vapors; at a higher tem-
perature it is decomposed into ammonia,
nitrogen, water, and ammonium sul-
phite, which sublimes, becoming finally,
at a red heat, entirely diaaipalea.
Ammonium sulphate is soluble in l.S
parts of water at lo^ C. (59'' F.), and in
Its own weight of boiling water, but is
sparingly soluble in aqueous, and in-
soluble in absolute, alcoiiul. The aque-
ous solution is neutral in its action upon litmus, possesses a strong
and unpleasant saline taste, and, similarly to ammoaium cLiloride,
AMMONIUM. 229
is partially decomposed on boiling, with the development of am-
monia. W hen heated with a solution of potassium or sodium
hydrate, it develops the odor of ammonia, and yields with a solu-
tion of barium chloride a white precipitate, insoluble in hydro-
chloric acid.
Examination :
Chlorides may be detected in the dilute aqueous solution of the
salt, acidulated with nitric acid, by a white precipitate on the
addition of solution of argentic nitrate.
Sulphocyanldes will be recognized in the aqueous solution by an
ensuing deep-red coloration on the addition of a few drops of solu-
tion of ferric chloride.
Metallic impurities (lead or copper) will be detected in the
aqueous solution, acidulated with hydrochloric acid, by a dark
coloration or precipitate upon saturation with hydrogen sulphide ;
after filtration, if necessary, ammonia- water in slight excess is
added, when an ensuing aark-colored precipitate will indicate
tVow, and a white one, zinc.
AMMONn VALERIANA8.
AMMONIUM VALERIANICUM.
Valerianate of Ammonium, Ammonium Valerianate.
Ger. Bald riansau res Ammonium ; Fr. Valerianate d^ammoniaque ; Sp. Vale-
rianato de amouiaco.
NH.C.H.O^; 119.
Colorless, transparent, quadrangular plates, or a white, trans-
lucent, crystalline mass, having the odor of valerianic acid, a
sharp, sweetish taste, and a neutral reaction. When heated, the
salt melts and emits vapors of the odor of ammonia and of vale-
rianic acid ; at a stronger heat it becomes black, with the evolu-
tion of pungent, inflammable vapors, and is at last wholly dissi-
pated. It is decomposed, and emits the odor of ammcmia, when
heated with a solution of potassium hydrate.
Ammonium valerianate is deliquescent in moist air, and is
freely soluble in water, glycerin, aiid alcohol; its aqueous solu-
tion, it not very dilute, separates, upon supersaturation with
acids, an oily layer of valerianic acid. The underlying aqueous
liquid, when nearly saturated with ammonia-water, should not
become red upon the addition of one drop of dilute solution of
ferric chloride, for in this case acetic ac/ti (admixture of potassium
or sodium acetate) would be indicated, which may also be recog-
nized by a fixed residue upon complete dissipation of the salt
upon platinum-foil, which residue will eftervesce when moistened
230 MANUAL OF CUEMICAL ANALYSIS.
with one drop of concentrated hydroclilnric acid. The aqaeOQs
solution of the salt, when ncidulated with nitric acid, and tested,
in separate portions, with barium chloride and argentic nitrate,
should iiftbrd no precipitate (absence of sulphates and chlorides).
AMTL HITRIS.
AMYUUH NITROSUM. AMTLiETHER NITROSU8.
yitrile »/ Atn^t' Amyl A'ifriU,
Ger. SttlpclrigsiiureiiniyleBler ; Fr. Azoiite d'smy le ; Sp. Amilonltrico.
c.n„NO,= c.n„-o-NO; 117.
A transparent liquid, of a pale yellow color, possessing an ethe-
real, fruity odor, and an aromatic taste. It has the specific gravity
of 0.»i)2 to 0.9026, and boils at 94 to 95" C. {201.2 to 203" F.),
yielding an orange -colored vapor, which, when ignited, burns
with a. yellow, luminous, and sooty flame. It is miscible, in all
proportions, with alcohol, ether, chloroform, lienzol, and benzin,
but not with water. When carefully pSaeed upon a mixture of a
solution of ferrous sulphate and concentrated sulphuric acid (Fig.
92), a brown zone will appear at the line of contact of the two
liquids.
Fifl. 92.
B Amy! nitrite, when perfectly pure jmd freshly prepared, is neu-
m tral in its action upon "litmus, but, upon long standing, or by ex-
I posurc to theflir, especially wlien containing water, it gradually
H acquires an aoid reaction, and then contains the various products
I i
AlIVL NITRI8.
231
myl
1, nitrous or nitric acid, valerianic acid, a:
valerianate, and am^Ho alcohol. When gently warmed with
, excels of a solution of potassium or sotliuni hydrate, it is readily
resolved into nitrous ac-id, which combines with the alkali, and
amylic alcohol, which floats upon the surface in the form of an
oil; if this alkaline mixture be su[)eTsatu rated with acetic acid, a
few drops of solution of potassium iodide, and subsequently a
little mucilage of starch added, a deep blue color will be produced.
Examination :
Alcnhnl find Wntirr. — The former may be recognized, and its
amouut also approximately estimated, by an ensuiug reductiou of
volume of the amyl ujtrite, when shnkcii with an
equal volume of water in a small graduated glass tube Fi»- 88.
or cylinder (Fig. 93); the presence of water will bo /ITk
indicated by a higher speciiio gravity than that above s}&
staled, and by a turbid appearance of the liquid when ^Kf
exposed to the temperature of melting ice.
Aldehyde may be detected by mixing a small por-
tion of the amyl nitrite with three times its volume
of a mixture of equal parts of ammonia-water and
absolute alcohol, subsequently adding a few drops of
solution of argentic nitrate, and warming gently ; an
ensuiug dark-brown coloration, due to the separation
of metallic silver, would indicate the presence of
aldehyde.
Free iteids may be detected in amyl nitrite when
tested with moistened blue litmus paper; and should
not be present in an amount sufficient to redden the
latter when 10 cubic centimeters of the amyl nitrite
are agitated with 2 cubic centimeters of a mixture of
I part of ainmonia-water and 9 parts of water, and
the liquid subsequently tested.
fft/drrtafanic acid, resulting as a by-product from
the action of nitrous acid on amylic alcohol, may be
reci^nized by diluting about 10 drops of ainyl nitrite willi ten
times its volume of alcohol, and adding thereto a few drops of
solution of argentic nitrate ; as hydrochloric acid does not occur
in amyl nitrite as an impurity, an ensuing white turbidity or
precipitate would indicate hydrocyanic acid.
This hook is the pro:
COOPER MEDICAL c^:.:. . .
8AN FRANCISCO. OAl^
one? M not tn l^ r- .wM-fi /«»» the
Libmiy !■■■ ' ' ' ' ' ■"'" '"■
ttndtr a>'y ;■
UASUAL OF CHEMICAL A!)ALT9IS.
AHTIMOini BT POTASen TAKTRAS.
V^a
CHfOHVCO-OK
K{SbO)C.H.O. + jH-O - I ■ + IH.O; 3S2.
CH(OH)-CO-<XSbO)
Colorless, raasparent, sliioiog, octabedral crystals of the rhom-
bic system, whicn. in conseqaence of the four remainiug alter-
nnting surfiices, ofcen assume a liemihedral, tetr&hedrou-like form
iFig. 94); or a white, granular pow-
er. The crystais have a specific
gravity of about 2.6, and cuntaio
one-half molecule ("2.7 per cent.) of
water of crystallization ; they efflo-
resce slightly when exposed to the
air, and lose their water of crrstalliza-
tion completely at lOS^ C. (226,4° ¥.),
becoming white and opaque; when
]x>wdered and heated in a dry test-
tube, tartar emetic emits acid empy-
rcuinatic vapors, and leaves a charred
residue wliicli, wlieii cool, turns moist turmeric-paper brown;
when the residue is placed upon charcoal and heaied before the
blow-pipe, white fumes are evolved, coating the coal, and brittle
globules (if antimony are formed.
Tartar emetic is soluble in 17 parts of water at lo" C. (59° F.),
in 3 parts of boiling water, and is also soluble in glycerin, but
insoluble in strong alcohol. Its aqueous solution has at first a
sweetish, afterwards a nau^ous metallic taste, a slightly acid
reaction upon blue litmus-paper, and gradually decomposes if not
concentrated or containing a small addition of alcohol; with the
mineral acids (not acetic, tartaric, and citric acids) a white turbid-
ity is pro<luced, which dLsap|>ear3 on the addition of a large exoess
of acid, and from the solution, upon the subsequent addition of
water, an abundant precipitate of basic antimonious chloride, sul-
phate, or nitrate is produced; its solution is also precipitated by
the alkaline hydrates, and by all soluble carbonates, but not by
bicarbonatea ; iho precipitate produced by the alkaline hydrates
being soluble in an excess of a solution of potassium or sodium
hydrate, but iusolnble in ammonia- water.
Hydrogen sulphide produces an orange-red color^ition in con-
ANTIMONIUM.
283
Fio. 95.
centrated solutions of tartar emetic, and gradually a precipitate of
the same color; in very dilute solutions, only a coloration takes
place; but, upon warming, or upon the addition of an acid, or
when the tartar emetic is contaminated with free tartaric acid or
potassium bitartrate, a turbidity ensues immediately.
Solution of tartar emetic reduces a solution of mercuric chloride
to mercurous chloride, gradually at common temperatures, and
quickly at elevated ones; and likewise reduces a solution of auric
chloride, with the separation of metallic gold.
If to a solution of tartar emetic a solution of potassium or
sodium hydrate be added, until the precipitate first formed is just
redissolved, and a solution of argentic nitrate subsequently added,
a copious dark colored precipitate of argentous oxide, Ag^O, is
produced, which is insoluble in ammonia- water.
Examination :
Arsenic is indicated by the garlic like odor when a small portion
of the powdered tartar emetic is at first gently heated in an iron
spoon, or in a porcelain crucible, and subsequently heated to
redness.
If the result of this test be doubtful, or confirmatory evidence
be required, a small quantity of the tartar emetic is dissolved, in a
test-tube, in concentrated hydrochloric acid, a little
concentrated solution of stannous chloride or a frag-
ment of pure tin-foil added, and the mixture gently
warmed ; the liquid must remain clear and colorless
on cooling; a brown turbidity or precipitate would
indicate arsenic. The presence of arsenic may be also
detected by adding to a little of the powdered tartar
emetic, contained in a test-tube, a small quantity of
powdered iron, a few fragments of metallic zinc, and a
concentrated solution of j)otassium or sodium hydrate;
the mixture is then gently heated, when, if arsenic be
present, hydrogen arsenide together with free hydrogen
will be developed, and impart a dark stain upon a piece of
bibulous paper moistened with a drop of a solution of
argentic nitrate, and placed over the orifice of the tube
(Fig. 95).
Metallic tinjnirities^ calcium salts^ chlorides^ and sul-
phates may be detected in a solution of 1 part of tartar
emetic in about 100 parts of water, acidulated with
acetic acid, by testing it, in se])arate portions, with solu-
tion of potassium ferrocyanide, aninioninni oxalate,
argentic nitrate, and barium chloride: a blue colora-
tion or precipitate with potassium ferrocyanide would
indicate iron, a reddish>brt»wn one, cojipf^r ; and a white
one, zinc ; an ensuing white precipitate upon the addi-
tion of ammonium oxalate, argentic nitrate, or barium chloride,
would indicate respectively calcium salts, chlorides or sulphates.
_^4^^»v
li
234 MANUAL or CBKMICAL A5AI.T5IS.
Potitsiium B'tartrott. — An admixture of this salt may be l_
proxinmt«lT rwxrgiiizeil by the difference of the solubility of Uirtar
emetic (1 : 17 1, and of cream of tartar (l:21l") in water at 15^ C.
(5ti' v.); when, tberefore, one pari of the tartar emetic is agitated
with \>i part£ of warm water, a cumplete solution inut^t takti plaue,
and remain tinebanged aAfr cooling. If cream of tartar be pre-
sent, it will se{iarate iu nroall cryataU. Ttie presence of pota8siura
hiurtnite, aa also of free tartaric acid, may be farther recopnixed
by Uie liberation of carbonic-acid gas, when a cold Ratorated sola-
lion of Kodium carbonate is poured upon the crystals.
The determioatton of the amount of pure tartar emetic con-
tained in any specimen of the salt may be accomplished by the
following methods:
I, Gravim^iric. — One gram of the uneRloresccd crystals, or the
same weight of the powdered tartar emetic previously dried at
IKt" 0. (230° F.), is dissolved, in a flask, in aboui 50 cubiccenti-
mcteni of water, the solution acidulated with hydrochloric acid,
gently warmefl, and completely saturated with hydrogeu sulphide;
the tiask is then loosely stojipered and allowed to stand in a
warm place for a few houra, the orange-red precipitate of anti-
mony Irisulphide. Sb,S,. collected on a tared filter, previously
dried at lOO-* C. (212° K.), quickly and thoroughly washed with
water to which a small quantity of water saturated with hydrogen
Kuliihide has been added, and finally thoroughly dried at exactly
100° C. ('212'^' K.i, until of constant weight. One gram of cryaul-
lized tartar emetic should thus yield 0.510 gram, or, if the salt has
Ijeen previously dried at 110° C. (230° F.), 0,523 gram of aotimoDy
trisulphide, Sb^^
II. VoUimttric. — 0,2 gram of uneffloresced crystals of tartar
emetic, or, if in powder, the same quantity previously dried at
110® C. (230° F.), is dissolved, in a beaker, in 10 cubic centimeters
of water ; about 20 cubic centimelers of a cold saturated solution
of sodium bicarbonate, and a little freshly prepared, neutral ranoi-
lage of starch are then added, and subsequently a decinormal solu-
tion of itxline (page H3) allowed to flow into the liquid from a
burette until, with constant stirring, a blue coloration, which for
a moment remains permanent, is produced ; the antimonious oxide
is thus converted into antimotiic acid, as represented by the
equation :
Sb,0, + 21. + CNaHCO, = fiNaSbO, + 4KaI + 3n,0 + 600,.
2K(SbO)<.',H.O,
With reference to the above proportion, one cubic centimeter
if decinormal itxline solution, corrected, if necessary, by its pro-
ANTIMONIUM. 235
per factor (page 95), corresponds to 0.0072 gram of antimonious
oxide, SbjOj, and to 0.0162 gram of anhydrous, or 0.0167 gram
of crystallized tartar emetic, K(SbO)C^H^Oj, 4- ilTjO ; from the
number of cubic centimeters of iodine solution employed, the
percentage purity of the specimen under examination may be
thus readily calculated.
ATIMONII OXIDUM.
ANTIMONIUM 8EU STIBIUM OXYDATUM.
Oxide of Antimony, Antimonious Oxide, Antimony Trioxide.
Ger. Antimonoxyd ; Fr. Oxyde d^antimoinc ; Sp. Oxido de antimonio.
SbPa; 288.
A grayish-white or pale-buff* colored, crystalline powder, when
obtained by precipitation ; or small, colorless, transparent, bril-
liant needles, when obtained by sublimation (Flores Antimonii).
When heated, antimonious oxide becomes yellow, and fuses at a
dull- red heat, forming a yellowish liquid, which solidifies, on
cooling, to a crystalline mass of a pearly color; at a higher tem-
perature, it volatilizes in white vapors, which condense, on cool-
ing, in colorless, shining, needle-shaped crystals; when mixed
and heated with exsiccated sodium carbonate on charcoal before
the blow-pipe, antimonious oxide is reduced, forming globules of
metallic antimony which are brittle when cold.
Antimonious oxide is insoluble in water, ammonia- water, sul-
phuric, nitric, and acetic acids, but is readily dissolved by warm
hydrochloric acid, with the formation of antimony trichloride; it
is also soluble in warm solutions of potassium or sodium hydrate,
and in solutions of tartaric acid, and the alkaline tartrates. Its
acid solutions aff()rd with hydrogen sulphide an orange-red preci-
})itate of antimony trisulphide, Sb^S,; its solutions in the fixed
alkaline hydrates are not acted upon by this reagent (distinction
from alkaline solutions of salts of lead and zinc), but, with argentic
nitrate, a black precipitate of argentous oxide is produced, which
is insoluble in ammonia- water.
Examination :
Aniimonic oxide may be detected by its much more sparing
solubility in hydrochloric acid; and by dissolving a portion of the
oxide in hydrochloric acid, diluting the solution with water, to
which a little tartaric acid has been added (in order to avoid
any turbidity by the separation of a basic salt), and adding
a solution of potassium iodide, free from iodate; the mix-
ture will remain colorless, if free from antimonic oxide ; but, if
the latter be present, it will assume a brown coloration, due to
the liberation of iodine, and when agitated with a few drops of
236 MAKUAL OF CBEMICAL A5ALTSI8.
chloroform or carbon bisulphide will imf«art to these liquids a
violet -red color.
AnUmonious oxy-chhride i Algaroth's Powder » and antimonuis
oxy-inlphatK are indicated by the formation of white precipitates,
when a dilute*! *f»lution of the oxide in an excess of tartaric acid
iff tested with argentic nitrate for the former, and with barium
chlori'ie for the latter. Their presence may be confirmed by
dijresting a little of the o.xide for about one hour with a cold con-
centrated 5^/*ution of sodium carbonate, filtering, and testing the
filtrate, after 5U[»ersatu ration with nitric acid, with argentic nitrate
for oji'j-rhlori'b'., and with barium chloride fur oxy-snl^hnie : an
ensuing white precipitate in either instance will reveal the re-
fij>ective impurity.
SU^nlUc nnumoroj will Ije indicated bv a grrav color of the oxide,
and will remain undissolved when the oxid« is treated with hydro-
chloric a': id.
Ar^'^nic is recognized by the garlic-like odor, when a little ox
the oxide is mixed with exsiccated sodium carbonate, and then
fu.sed and replaced upon charcoal before the blow-pij.>e. Its
presence may be confirmed by dissolving a small pCortion of the
oxide in concentrated hydrochloric acid, subsequently adding a
few dropj? of a concentrated s^jlution of stannous chloride, or a
fragment of [»ure tin foil, and warming the mixture gently; the
liquid -iiould remain clear and colorless on cooling; a brown tur-
bidity or precipitate will indicate arsenic.
Estimation:
I. Oravhn*tfrlc. — A weighed portion of the oxide (about 0.5
gram; isdiss'^lved in hydrochloric acid, the solution largely diluted
with water^ to which a little tartaric acid has been added, in
order to prevent precipitation, and after warming, completely
saturated with hytlfogen sulphide; the flask is then loosely
str>pjK;red, and allowed to repose in a warm place for a few
hours: the precipitate of antimony trisulphide is collected upon
a tared filter, [)revionsly dried at 100° C. 0212- F.», quickly and
thorou^^hly washed with water to which a small quantity of water
saturated with hydrogen sulf)hide has been added, and finally
thoroughly dried at exactly 1U0° C. (212° F.) until of constant
weight : 100 ]>arts of antimonious sulphide. S*>,S,, correspond to
'So. 71 parts of antirnonious o.\ide, Sb/)^
II. Vohniu'/ric. — 0.1 gram of the oxide is diss.>lved, in a beaker,
in about lo cubic centimeters of water, to which the required
cjuantity of tartaric acid has been added to elVect solution, the
solution exactly neutralized with sodium carbonate, and subse-
quently about 20 cubic centimeters of a cold saturated solution of
s^xliurn bicarbonate, and a little freshly prepared neutral muci-
lage of starch added; a decinormal solution of iodine (page 03) is
then allowed to flow into the liquid from a burette until, with
constant stirring, the blue coloration which is produced remains
ANTIMONIUM. 237
for a moment permanent ; the antimonious oxide is thus converted
into sodium antimoniate, as represented by the following equation :
Sb.O^ + 21, + 3Na,C0, = 2NaSbO, + 4NaI + 3C0,.
288 508
(7.2) (12.7)
With reference to the above proportion, one cubic centimeter of
the decinormal iodine solution, corrected, if necessary, by its
proper factor (page 95), corresponds to 0.0072 gram of antimonious
oxide, SbjOj^ which, multiplied by the number of cubic centi-
meters of iodine solution employed, will give the amount of pure
antimonious oxide in the specimen under examination.
ANTIMONII SULPHIDUM.
I ANTIMONTT SULPHURETUM. ANTIMONTUM SULFURATUM
NIGRLM. STIBIUM SULFURATUM CRUDUM.
Native Sulphide of Antimony. Trisulphide of Antimony. Antimonious
Sulphide,
Ger. Graaes Schwefelantiroon (Spiessglanz) ; Fr. Sulfure d^antimoine ;
Sp. Sulfuro de antimonio.
Sb,S,: 336.
Heavy fused masses, which, when broken, present a striated
crystalline texture, and a lead-gray metallic brilliancy ; when
pulverized, they form a dark iron-gray powder. Spec. grav.
about 4.6. When heated upon charcoal before the blow-pipe,
black antimonious sulphide fuses and burns, emitting dense white
fumes and the odor of sulphurous acid ; when mixed with some
dried sodium carbonate and potassium cyanide, and heated in the
same way, metallic globules are obtained, which are brittle when
cooled.
Black antimonious sulphide, when reduced to a fine powder, is
insoluble in water, alcohol, the dilute mineral acids, and organic
acids, with the exception of tartaric acid, which, at the boiling
temperature, dissolves it to a certain extent, with the liberation of
hydrogen sulphide, and the formation of antimonious tartrate; it
is readily soluble, however, in concentrated hydrochloric acid,
with the formation of antimony trichloride, and the development
of hydrogen sulphide; and in hot concentrated sulphuric acid,
with the formation of antimonious sulphate, separation of sul-
phur, and development of sulphur dioxide. With concentrated
nitric acid it is oxidized to antimonious nitrate, with the forma-
tion of some antimonious sulphate, separation of sulphur, and
development of nitrogen dioxide ; nitro-hydrochloric acid dis-
238 MAHCAL 0? CHEMICAL ANALYSIS.
solves it with the formation of anliinonv trichloride and Ralpoi
ric acid, accompanied by the aeparatiou of sulphur. The solution
in hydrochloric acid, when dropped into water, produces u copi-
ous white turbidity, which becomes orange-red id coulact with
hydrogen sulphide (a brown or black color of the precipitate
would indicate the presence of lead or other metals). Black anti-
moniouD sulphide is also partially dissolved by boiling concen-
trated solutions of potassium or sodium hydrate, with the forma-
tion of aulpho-salts (sulphaiitimonites), leaving a brown residue,
consisting of a mixture of oxysulphide and antimoiiite; it is
almost insoluble in ammonia-water (distinction from arsenic tri-
salphide).
The native antimonious sulphide generally contains sulphides
of iron, lead, cof^r, and arsenic; and there arc also found, espe-
cially in the commercial black powder, silicates and mineral ad-
mixtures, while occasionally an article sold under the name of
" black antimony" has been found to consist simply of a mixture
of powdered lime-stone and anthracite coal.
zbiatDlnatton ;
MkIuIVc impurities (iron, lead, and copper), which, as previously
stated, are usually present in variable proportions in native anti-
monious sulphide, will be indicated by a yellowish or brownish
residue when about two grams of the finely -powdered sulphide
are intimately mixed with four times its weight of sodium nitrate,
the mixture cautiously ignited in a porcelain crucible, and the
fused mass subsequently boiled with about three times its weight
of water, to which a little alcohol has been added. The further
identification of such impurities may be effected by the method
described in detail under antimonium sulphnratum, on page 244,
Arsenic may be detected in the filtrate of the preceding test by
acidulating it with nitric acid, boiling until nitrous vapors cease
to be evolved, subsequently adding a few drops of solution of
argentic nitrate, again filtering, if necessary, and finally pouring
upon the surface of the clear solution, contained in a test-tube, a
few drops of ammonia-water; a white cloud at the line of contact
of the two liquids will indicate traces of arsenic, whilst if larger
amounts are present, a red or reddish-brown precipitate will be
produced.
Admixtures of black manganic peroxide, of pyrites, and of
other crude minerals, are recognized by their infusibility when
heated in the ordinary gas-flame, whereas black antimonious sul-
phide readily fuses at this temperature, and also by dissolvinr
the black powder in boiling hydrochloric acid; the first-named
gives rise to the evolution of chlorine, the latter remain mostly
undissolved.
The artificially prepared black antimonious sulphide contains
frequently more or less metallic antimony, which may be recog-
nized by iUi insolubility in warm hydrochloric acid, remaining
ANTIMONIUM. 289
behind in minute brilliant iron-gray particles, which, however,
dissolve upon the addition of potassium chlorate, and subsequent
heating.
Silica may be recognized by its remaining undissolved when
the sulphide is heated for a short time with about ten parts of
nitro-hydrochloric acid, whilst the unoxidized sulphur will prin-
cipally float upon the surface of the liquid as a spongy mass. The
silica, after washing with a solution of tartaric acid, and subse-
quently with water, will remain unchanged upon ignition, and,
when heated with a little borax on a platinum wire in the non-
luminous flame, will produce the characteristic skeleton in the
bead.
A mixture of limestone and coal, the occurrence of which as
a sophistication of commercial black antimonious sulphide has
been previously alluded to, maybe readily recognized by treating
the powder with warm hydrochloric acid; the carbon will remain
undissolved, and the clear, filtered solution, after dilution with
water and the addition of sodium acetate in excess, will afford,
upon the addition of a few drops of a solution of ammonium oxa-
late, a white precipitate of calcium oxalate.
Estimation :
The estimation of the amount of pure antimony trisulphide in
black antimonious sulphide may be best effected by the following
method : A weighed amount (1 gram) of the very finely powdered
sulphide is dissolved, in a flask, in hydrochloric acid, with the aid
of a gentle heat and the addition of a small quantity of nitric acid,
the solution slightly supersaturated with potassium hydrate, and
subsequently a solution of potassium sulphide added, and digested
at a gentle heat; the sulphides of lead, copper, and iron will
thereby remain undissolved, whilst the antimonious sulphide,
together with arsenic, if present, will be obtained in solution :
As,S, + 2KIIS = 2KAsS, + H^S.
After cooling, the mixture is filtered, the undissolved portion
well washed upon the filter with water, and the combined filtrate
and washings saturated with sulphur dioxide gas until the latter
ceases to be absorbed. The antimony, together with the arseni-
ous sulphide, becomes thereby precipitated, but by subsequent
digestion of the mixture upon the water-bath, and afterwards
boiling until about two-thirds of the water has evaporated, and
the escaping vapors no longer possess the odor of sulphur dioxide,
thearsenious sulphide becomes redissolved, whilst the antimonious
sulphide, associated with some sulphur, remains insoluble:
4KAsS, + 5S0, -f 2H3O = 2 As^S, -f S3 + 4KIIS0,;
2 AsjS, + 16KHS0, « 4KAsO, -f HK^S.O^ 4- 8H,0 + S,^ 7S0,.
The insoluble residue is then filtered, thoroughly washed with
water, dried at 100® C. (212° F.), and the free sulphur completely
240 MAVCAL OF CHEMICAL ASALYSIS.
removed by washing it upon the filter with pure carbon bisul-
phide, until the washings upon evaporation no longer leave a
deposit of sjilphur. After the above treatment, it is brought into
a weighed |»^»rcelain crucible, moistened with a few drops of nitric
acid, fspec. grav. 1.12, then eisrht to ten times its weight of fuming
nitric acid added, and the acid subsequently allowed to evaporate
gradually on the water-bath. The sulphur which is at first sepa-
rate<l l>ecomes completelv oxidized to sulnhuric acid, and the
antimonious .sulpiiide converted into aniinionic acid. The cruci-
Vile, and its contents, are then first gently heateil to expel the sul-
phuric acid, and finally heated to redness, whereby the antimonic
acid is converted into antimony orthoantimonate, Sb,0^ and,
after c«x>ling, is weighed as such ; 1<K) parts of the latter compound
corresf>ond to 110.52 parts of antimony trisuljjhide, Sb^,
AHTIMONII SULPHIDUM AURANTIACUM.
ANTIMOMUM SEU STIBIUM SULFURATUM .\URANTIACUM.
SULFUR AUR.VTUM ANTIMONII.
0 olden Sulphur. Pentatulphide of Antimony. Aniimonie Sulphide,
Ger. Antimonsulfid. Goldscliwefel ; Fr. Sonfre dore d*antimoine ;
Sp. Bisulfaro de antimonio bidratado.
Sb,S,; 400.
A fine oranjrc-red powder, nearly odorless and tasteless, becom-
ing gradually lighter colored by the action of air and light, and
at the sarno time underiroing slow oxidation with the develop-
ment of sulf)hurous acid gas; when heated in a dry test-tube, it
gives oft' sul[»hur, leaving behind black antimonious sulphide;
when heated iijjon cliarcoal before the blow-pi|x», it burns away
with a pale, V)luish flame, emitting the odor of sulphurous acid
gas, and causing a white incrustation of the coal.
Antimonic suljihide is insoluble in water, alcohol, and ether,
and is but slowly decomposed by the organic and dilute mineral
acids. When treated with ten to fifteen times its weight of
warm concentrated hyclrochloric acid, it dissolves for the most
[)art with eftervescent evolution of hydrogen sulphide, leaving
behind a scanty residue of red-colored sulphur; the solution,
when dejirived of the hydrogen sulphide by heat, produces, when
dropped into water, a white turbidity, disappearing upon the ad-
dition of tartaric acid, which solution is precipitated orange-red
by hydrogen sulphide.
Antimonic sulphide is completely soluble in a warm solution
of potassium hydrate, in solutions of the alkaline sulphides and
sulphydrates, and in warm solutions of the alkaline carbonates,
ANTIMONIUM. 241
with the exception of ammonium carbonate (distinction from
arsenic sulphide); it is also nearly or completely dissolved by
about 150 times its weight of an aqueous 10 per cent, solution of
ammonia, spec. grav. 0.960 ; if a small residue is left, it will dis-
solve in a solution of tartaric acid, or of potassium hydrate, on
boiling.
Examinatioii :
Sodium Salts, Sulphates, and Chlorides, — A small portion of the
antimonic sulphide is digested with frequent agitation for about
15 minutes with ten times its weight of tepid water, filteredj and
the filtrate evaporated to dryness; if a residue is obtained which
imparts a bright yellow color to the non-luminous flame, soditcm
salts will be indicated. The residue is then dissolved in a little
water, acidulated with nitric acid, and tested, in separate por-
tions, with barium chloride for sulphates, and with argentic ni-
trate for chlorides ; an ensuing white precipitate in either instance
will reveal the respective impurity.
Sulphur, Kermes Minerale, and Antimonions Oxide. — A portion
of the antimonic sulphide is digested with frequent agitation for
about 15 minutes with 150 times its weight of strong ammonia-
water ; the above-mentioned impurities will thus remain uudis-
solved, and, after separation by filtration, may be further exam-
ined as follows : Sulphur may be detected in the insoluble residue
by its complete volatilization when strongly heated, with the
development of sulphurous acid gas, and, when present in the
free condition in the antimonic sulphide, may be extracted and
quantitatively estimated by means of carbon bisulphide, which
will deposit it in a pure state upon evaporation ; kermes ruinerale
will be recognized by its reddish-brown color, and solubility in
hydrochloric acid with the evolution of hydrogen sulphide and
formation of antimony trichloride; antimonious oxide may be
detected by its complete solubility in a solution of tartaric acid,
and the solution, after acidulation with hydrochloric acid, will
yield a reddish-yellow precipitate of antimony trisulphide upon
saturation with hydrogen sulphide.
Arsenic may be detected by digesting the antimonic sulphide,
with occasional agitation for about half an hour, in a closely stop-
|)ered flask, with a concentrated solution of ammonium carbonate,
and filtering; the filtrate is then supersaturated with hydro-
chloric acid, when the formation of a lemon-yellow precipitate,
either at once or upon subsequent saturation with hydrogen sul-
phide, will indicate the presence of arsenic. As traces of anti-
monic sulphide are also dissolved by ammonium carbonate, and
would likewise be precipitated by supersaturation with an acid,
the presence of small amounts of arsenic may be more accurately
determined by the method of fusion with sodium nitrate, as ex-
plained in detail under antimonium sulphuratum, on page 243.
16
242 MANUAL OF CHEMICAL ANALYSIS.
Lead, Copper, and Iron, — The sulphides of these metals will
remain undissolved when a portion of the antimonic sulphide is
digested with a solution of potassium sulphide. The insoluble
residue, after washing with water, is dissolved in a little warm
nitric acid, the solution diluted with water, heated to expel the
excess of nitric acid, and, after filtering, is tested in separate por-
tions, as follows : To a })ortion of the solution a few drops of a
solution of potassium ferrocyanide are added, when a blue pre-
cipitate will indicate iron ; to another portion of the solution a
few drops of dilute sulphuric acid are added, when a white pre-
cipitate will irdicate lead ; and, after the removal of the latter
by filtration, and subsequent supersaturation of the liquid with
ammonia-water, a blue coloration will reveal the presence of
copper.
Calcium salts niay be detected by agitating the antimonic sul-
phide with water slightly acidulated with hydrochloric acid, and
filt ring ; after the addition of a considerable excess of sodium
acetate to the filtrate, a few drops of a solution of ammonium
oxalate are added, when an ensuing white precipitate will indi-
cate calcium.
ANTIMONIUM SULPHURATUM.
STIBIUM SULFURATUM RUBEUM.
SulphurnUd Antimony, Mineral Kermes. AntimoniouM Oxy^ulphide.
Ger. Brauiies Scliwofelantimon ; Fr. Sulfnre d'antimonine hydrate ;
Sp. Protosulfuro dc nntiiiionio liidrutudo.
SbjS3 -f ;/Sb.^03.
An insipid powder of a reddish-brown color, becoming gradu-
ally lighter by the action of air and light. It is a mixture of
antimonious sulphide with a small and variable amount of anti-
monious oxide, the former appearing under the microscope in
amorphous globules, or lamina^, and the latter in small, colorless
crystals, or frngments of such. When heated upon charcoal
l)efore the blow-pipe, sulphurated antimony fuses and burns away,
with the evolution of white fumes, and the odor of sulphurous
acid; heated with the addition of a little dried sodium carbonate,
brittle globules of antimony are obtained.
Sulphurated antimony is insoluble in water and alcohol, but
readily and wholly soluble in hydrochloric acid, which solution,
after the hydrogen sulphide has been completely expelled by heat,
gives a white precipitate when dropped into water, which, how-
ever, is re-dissolvcd upon the addition of tartaric acid; this solu-
tion yields an orange-red precipitate with hydrogen sulphide.
Sulphurated antimony is only slightly soluble in ammonia-water,
AXTIMONIUM. 243
but is dissolved by a warm solution of potassium hydrate, with
the formation of potassium antimonite and sulphantimonite, and
«hould also form a clear, colorless solution, with the exception of
an inconsiderable insoluble residue, when heated to about 90** C.
(194** F.), with 200 parts of a solution of 1 part of sodium car-
bonate in 2 parts of water. When treated with a solution of
tartaric acid (1 part of acid to 8 parts of water), the antimonious
oxide is dissolved, whilst the antimonious sulphide remains un-
affected; the latter, however, is completely soluble in a solution
of potassium hydrate.
Examination :
When a small quantity of sulphurated antimony is agitated
with water and filtered, the filtrate must not affect either blue or
red litmus-paper, nor leave a residue when evaporated upon plati-
num-foil; a crystalline residue effervescing upon the addition of
an acid will indicate sodium carbonate. The residue may then be
dissolved in a little water, acidulated with hydrochloric acid, and
tested with barium chloride, when an ensuing white precipitate
will indicate sulphates,
Antimonious oxide and sodium antimojiite may be detected, and
at the same time quantitatively estimated, by agitating the sul-
phurated antimony repeatedly with a solution of tartaric acid,
when they will become dissolved, and, from the clear liquid, acidu-
lated with hydrochloric acid, the antimony may be subsequently
completely precipitated by hydrogen sulphide as antimony trisul-
phide, dried at 100^ C. (212° F.), weighed, and therefrom the cor-
responding amount of antimonious oxide calculated. The amount
of pure sulphide or of the oxide therein contained may likewise
be determined by thoroughly washing the portion undissolved by
the tartaric acid with pure water, drying, and subsequently deter-
mining the loss of weight.
Arsenic may be detected by digesting a portion of the sulphurated
antimony with a cold saturated solution of ammonium carbonate,
when the arsenious sul]>hide will be dissolved, and may be re-pre-
cipitated from the solution by supersaturation with hydrochloric
acid, and subsequent saturation with hydrogen sulphide. The
most reliable method, however, for the detection and separation
of the arsenic is as follows: One part of the powder is intimately
mixed with 8 parts of sodium nitrate, and the mixture is brought,
in small portitms, into a small porcelain crucible, previously heated
to a low, red heat, and containing 1 part of j)ure sodium nitrate;
the heat is then maintained until complete deflagration and oxida-
tion of the melted mass is effected, after which the contents of the
crucible may be removed while still warm, then allowed to cool,
subsequently reduced to powder, and digested with the necessary
quantity of a mixture of 1 part of alcohol and 5 parts of water.
The antimony thus remains as insoluble sodium antimoniate,
together with ferric and cupric oxides and lead antimoniate, if
these metals are present, whilst the solution will contain the
2-14 manoal of chemical AXAH'srs.
nracnic in the form of soluble sodium arseriinte, topether with
sfHliiim Fulphnte, nitrite, and undecomposed nitrate. Tlie filtered
solution is then acidulated with sulphuric acid, evajioraied to
dryness, the residue dissolved in water, and, after warming to
alwut fiO^ C. {140^ F,), saturated with hydrogen sulphide; the
arsenic is thus, together with a little separated sulphur, com-
pletely precipitated as yt-lJow arsenic trisulphide; or the filtered
solution, as originally obtained by the extraction of the fused
mass with waler containing a little alcohol, is acidulated with
nitric acid, boiled in order to remove all traces of nitrons acid,
and a few drops of a solution of argentic nitrate subsequently
added, when, in case a turbidity is produced by the separation of
argentic chloride, the solution is again filtered; a few drops of
ammonia- water are then carefully poured upon the surface of the
solution, contained in a test-tube, when in the presence of small
amounts of arsenic (not exceeding i*a of i per cent.), a white oloadi-
ness will appear at the line of contact of the two liquids, whereas
with larger amounts a more or less reddish-brown precipitate of
silver arscniate will be produced, soluble in nn excess either of
ammonia-water or of nitric acid. If the result of the above test
should leave any doubt as to the presence or absence of minute
Quantities of arsenic, it may be made still more delicate, by ren-
ering the above solution to which the argentic nitrate was added
strongly ammoniacal, evaporating to dryness in a porcelain cap-
sule by the aid of a gentle heat, treating the residue with water,
and finally bringing the solution, together with any adhering un-
dissolved particles of silver arseniate, upon a small filter; after
tboTough washing with water, the undissolved residue upon the
filter is dissolved in hydrochloric acid, the solution diluted slightly
with water, filtered, and tested in itarsh's ap]iaralus, as described
on pages 83 lo 36.
Iron, Lend, and Copper. — To a portion of the sulphurated anti-
mony, contained in a porcelain capsule, concentrated nitric acid is
added, and the mixture evaporated upon the water-bath to dry-
ness, the operation being repeated with the addition of more nitric
acid, if necessary, until complete oxidation is effected; to the
residue, water is added, and repeatedly evaporated to drvuesa,
until the free nitric acid is completely eliminated ; the residue is
then treated with dilute nitric acid, the solution filtered and tested
in separate portions as follows: To a portion of the solutions
few drops of a solution of potassium ferrocyanide are added, when
a blue precipitate will indicate iron; to another portion of the
MilutioD a few drops of dilute sulphuric acid are added, when a
white precipitate will indicate lead, and, after the removal of the
latter by filtration, and subsequent supersatu ration of the liquid
with ammonia-water, a blue coloration will reveal the presence of
mpper.
Admixtures of .powdered silicates (brick-dust, etc.) remain
un fused before the blow.pi]H\ and undissolved in hydrochloric acid.
APOMORPHINA. 245
APOMORPHIN2I H7DROCHLORA8.
APOMORPHINUM HYDROCHLOHICUM.
Hydrochlorate of Apo morphine. Apomorphine Hydrochlorate,
Ger. Cblorwasserstoffsaures Apomnrpbin ; Fr. Hydrochlorate d^apomorphine ;
Sp. Clorhidrato de apomorfina.
C,,n,,NO,.HCl ; 303.4.
A white or grayish- white, crystalline powder, without odor,
but possessing a bitter taste, and a neutral or faintly acid reaction.
By exposure to light and a moist atmosphere, it readily absorbs
oxygen and assumes a green color; in contact with concentrated
nitric acid it produces a blood-red; with a dilute solution of ferric
chloride an amethyst-red; and with molybdic acid a bright-green
coloration. When strongly heated on platinum-foil, it burns en-
tirely away, without residue.
Apomorphine hydrochlorate is soluble in 6.8 parts of water,
and in 50 parts of alcohol at 15° C. C59^ F.), but is slowly decom-
* posed by boiling water or boiling alcohol, the solution acquiring
an alkaline reaction, and, when concentrated, a greenish-brown
color; it is almost insoluble in ether or chloroform, but soluble
in an excess of a solution of sodium hydrate, forming a solution
which, on exposure to the air, quickly assumes a purple-red color,
and afterwards becomes black.
The aqueous solution of the salt, when freshly prepared, is
colorless and neutral in its action upon litmus, and yields with a
solution of sodium bicarbonate a white amorphous precipitate of
apomorphine; this precipitate rapidly acquires a green color by
exposure to the air, and then forms a bluish-green solutiou with
alcohol, a purple one with ether or pure. benzol, and a violet one
with chloroform. The liquid from which the alkaloid has been
precipitated, after supersaturation with nitric acid, yields, with a
solution of argentic nitrate, a white precipitate of argentic chlo-
ride, insoluble in nitric acid, but soluble in ammonia- water.
AQUA AMMONI2I.
LIQUOR AMMONIiE. AQUA SEU LIQUOR AMMONII CAUSTICI.
Water of Ammonia, Solution of Amtnonia.
Ger. Salmlakgeist ; Fr Aminoniaque liquide ; Sp. Soiucion acuosa dc amoniaco.
A colorless, transparent liquid, consisting of an aqueous solu-
tion of amuionia gas; the latter being soluble in water to an
extraordinary degree, with the simultaneous development of heat.
The degree of absorption of the gas by water is dependent upon
the temperature and pressure; according to recent determinations,
one volume of water absorbs :
ml Oc C-t3SO P.) 10.10 voliinips of gns. »t l.-p Ct.lll" F.) 727 voloi
'• r,oC(4lot\) 1118 30O(!.<S8OF'.)8M
"10OC.(50oF0 Hl3 " " ■'2->oc.(77OF.i680 "
The quantity of ammonia cniiiaiiifd in tlic c<>iiiiiier<;i!il and olli-
cinal siilutionx varies from '62 to 10 per cent, by weight of gas;
the latter strength correspouding with a spec. grav. of 0.9oV at
15" C. (oS"* F.), being the average strength of the aqua ammoniae
uf the majority of the pliarmauopoeias. The United States and
the British pbarmacopwias include ubo an almost saturated solu-
tion, Aqua Animnniae Forlior; llie former of 0,900 spec, grav.,
containing 28 per cent., the latter of 0.891 spec, grav., containing
32.5 (ter cent, of the gas.
Tiiix gas is alsi) soluble in iileuhol. which solution is officinal
as Spiritns AmnioniiG, or Liquor Ammuuii caustioi spiriluusus
(Spiriius Ammoniaci eaustici Dzondii), generally of a strength
eonlaining 10 to 12 per cent, of tlie gas.
These solutions have the properties of the gaseous ammonia,
its pungent odor, sharp burning taste, and causiiu action upon
animal membranes; they have a strung alkaline reaction, and form ,
white fumes when brunght in contact with the vapors of dilo-
rine or acids, however diluted willi alm'wpheric air ihcy may be.
.Solution of ammonia is miscible in nil proportions with water,
glywrin. and alcohol, and is neutralized by all acids with the
foniiiition of mostly well crvBtallizable salts; it decomposes and
precipitates most of the earthy and metallic oxides from their
conipouniis; several of these precipitates are redissolved by
an excess of the precipitant. It also precipitates most of the
alkaloids.
The purity of oommercial aqua ammonia depends upon the
mode of preparation, the materials employed, and the water use<i
for the absorption of the gas. For medicinal use, distilled water
ought to bd employed, while this precauliou is not required for
solutions used in the arts and trades. The strength of solutions
of ammonia may be determined by ascertaining their sgiecilic ,
gravity ; this method, however, is reliable and accurate only when
the water contains ammonia alone, and is free from other, and
especially from fixed sub^taEices, whicli would increase the specific
gravity of the solution.
ExaminatiDiL ;
Fixed s'lhC'inces are recognized by a residue npnn the Rvapora-
lion of the iiqiia ammonia; in a glass capsule or on a watch-glass.
Ammouiuiii carLohale is detected by mixing equal volumes of
aqua ammonia and lime-water; a turbidity would indicate car-
bonate. The United States Pharmacopoaia limits the amount of
carbtmic acid to the production of at most but a faint cloudiness
vhen mixed with five times its volume of lime-water.
Empyrevma, if not recognized by the odor, will be distinctly
developed when the ammonia- water is neutralized by diluted sul-
phuric acid, and, when slightly aupjrsaluraicd with the acid, and
AQUiB. 247
subsequently diluted with water, the solution will decolorize a
solution of potassium permanganate, if such impurities are present.
Tarry matters^ which- invariably contain traces of aniline and
toluidine, are also detected by adding the ammonia- water, drop
by drop, to a little colorless nitric acid, previously diluted with
one-fourth its volume of water, in a test-tube, when the liquid
will acquire a rose or deep-red coloration, gradually changing to
brown upon the further addition of ammonia- water, and disap-
pearing entirely if the latter is added in excess.
Calcium salts are recognized by a white precipitate of calcium
oxalate on the addition of a solution of oxalic acid or ammonium
oxalate.
Chloride, Cyanide, and Sulphate, — A portion of the ammonia-
water is slightly supersaturated with nitric acid, and the solution
evaporated on the water-bath to dryness. The residue is then
dissolved in a little water, filtered, if necessary, and tested in
separate portions with argentic nitrate for chloride and cyanide,
and with barium nitrate for sulphate; when a precipitate has
been formed with argentic nitrate, its nature may be ascertained
by slightly supersaturating a little of the ammonia- water with
hydrochloric acid, and subsequently adding to the solution a few-
drops of a solution of a ferrous and ferric salt; a blue coloration
or precipitate would indicate the presence of cyanide ; if such
reacti<m does not occur, the silver precipitate, if insoluble in
diluted nitric acid, consists of argentic chloride.
Metallic impurities will remain behind upon the evaporation of
a little of the ammonia-water, and will also be precipitated by
hydrogen sulphide, either before or after neutralization with
hydrochloric acid.
Estimation :
The strength of aqueous solutions of ammonia, if free from
fixed or other impurities, may be approximately determined by
ascertaining the specific gravity, and reference to the subjoined
table. Of the officinal Aqua Ammoniae, containing 10 per cent,
by weight of ammonia gas, 100 parts should dissolve, without
effervescence, 87.058 parts of pure, crystallized oxalic acid, to form
a perfectly neutral, clear, colorless, and odorless liquid.
The ammonia strew/th of pure aqua ammoniie, or of crude am-
moniacal liquors (free from other alkaline hydrates or carbonates),
may be more accurately estimated, however, by the following
simple method of volumetric analysis: A convenient quantity of
the liquid (10 grams) is accurately weighed in a flask, a few
drops of litmus solution added, and a normal solution of oxalic
or sulphuric acid (page 82) allowed to flow into the liquid from a
burette until, with constant stirring, a permanent red tint is pro-
duced. If exactly 10 grams of a 10 per cent, solution of ammo-
nia are employed for the test, 59 cubic centimeters of the normal
acid will be required for neutralization. As, however, one cubic
centimeter of the normal acid, corrected if necessary by its proper
248
factor, c
MANUAL OK CHE.MICAL ANALYSI
rrefiponds to 0.017 grams of ammonia
number.
when multiplied by tlie number of cubic centimeters of "■
auid required for neutralization, will indicate tlie exact amouutof ■
ftinmonia contained in tlie solution, and tberefrom its percentage ■
strength
may be readily calculated.
1
Table of the quantits 6y wi^ight of Am-no'i^a ci»*.'iinid in HID p;rtt bj/ |
leeifflit of Aqua Ammonia! of difftretil iptnfie gTOvitiet (Car
;«o-
Temperslure 14° C. (57.23 F.;.
BlwIBg
•^'r'- op"-^
Pff cent.
SpMlttc
P.t will.
Sprelfle
[•».„..
(immr.
AODWllUl. K"'"?-
*'""-»'•■
»«.!.)-.
A»Bor,U
A«»>l>.
0.S844
S6 0 1 o.oosa
37.0
0.8314
18.0
0.8631
8.0
O.H048
S5.8 , 0.0057
36.8
0.0331
17 H
0.8080
8,8
ll.8».VJ
8.5.6 0-000!t
36.6
0.0837
17 6
0.8647
8.6
0.8856
85.4 0-0068
28.4
0.0333
17.4
0.06.54
8.4
0.88G0
B5.a 0,0073
26 3
0.0340
17.3
0.8603
8.3
0.8MM
tIS.O 11.0078
0.08*7
17-0
0.9670
8.0
0.8808
34.8 0.0083
25.8
0.0858
10. f*
0.B677
7.8
0.8B78
34.6 0.0080
3-1.6
0.0860
16. S
0,1)685
7.6
0.B877
84.4 ' O.UOe4
85.4
0.D306
Ifl.4
0.9083
7.4
O.SHttl
34 a 1 0.8100
35.3
0.8378
16.3
0.H7O1
7.3
0.888B
34.0 ' O.OlOfl
3.1.0
0.9380
16.0
0.0700
7.0
0.88ye
88.8 oom
34.8
0.8386
15.8
0.0717
6.8
0.8801
83.6 1 0.0116
34.6
O.ftiOS
15.6
0.0735
6.6
O.SB'JS
S3. 4 1 Q.^m
34.4
0.0400
15.4
0.0738
0.4
0.(jW3
83.3
0.0137
34.3
0.0407
i5.a
0.0741
S.3
0.8H07
83.0
0,8188
34.0
0.9414
15.0
0.8740
o.o
O.Win
33,8
0.0180
38-8
0.9490
14. 8
0,0757
fl.8
0.8U1S
as. 6
U.OI45
38-6
0.9427
14.6
0.9765
5.6
0.61130
0.01 no
23.4
0.0484
14.4
0.0773
5.4
0.8825
83.2
0 0150
33-3
0.0441
14.3
0.07H1
5.3
0.8020
33.0
0.8163
23.0
0.0440
14.0
0.0700
5.0
0.80»4
31.8
0.0168
aa.8
0.0456
13.8
0.0708
4.8
o.euas
81.6
0.U174
32.6
0.0463
13.0
0.0807
4.S
0.8048
81.4
0.K18O
23.4
0.H470
13.4
0.0815
4.4
0.8048
81.3
0.0183
23,3
0.8477
18.3
0.0833
4.3
0.BBS8
81.0
O.OIOI
0 8484
18.0
0.0831
4.0
O.BK.IT
80.8
0.0107
31.8
0.8401
13.8
0.0880
».B
O.BMa
80.6
0.11203
31.6
0,9408
13.0
0,8847
8.6
0.S807
80.4
O.USOO
31.4
0.0505
13.4
O.nS.'iS
8.4
0.8071
80.3 1 0 8315
31.2
0.8513
13.3
0.8868
3.3
0.887(1
80.0 0.U32I
31.0
0.0530
13.0
0.0878
8-0
0.t>S81
26.8 0.8337
20.8
0.0527
11.8
0,»883
3.8
0.8980
29.0 0.0338
30.6
0.0584
U.O
0,8890
2.B
0 8Hw1
30.4 0.0288
30.4
0.0.543
11.4
0,0890
3.4
o.e»»6
98.3 0.0345
30.3
0.0540
11.3
0.H0O7
3.2
O.UOOl
20.0 ) 0.0351
30.0
0.B5.56
11.0
0.8015
8.0
0.8006
28.8
0.03.17
10.8
0.8563
10.8
0.0834
1.8
O.OOIl
28.6
0.B2S4
10.8
0.0571
10.6
0.9033
1.6
o.wie
38.4
0,0371
18.4
0.0578
10.4
0.0H41
1.4
O.WMI
38.3
0.0377
10.2
0.0586
10.2
0.0050
1.3
0.8036
28.0
0.0388
10.0
0.B5B8
ID.O
0.8859
1.0
0.8081
27.8
0.8380
18.8
0.0601
8.8
0.1W67
0.8
0.9080
37.6
0.0200
18.6
0.0008
B.n
0.0875
0.6
O.MHl
37.4
0.0803
18.4
0.0616
0.4
0.0083
0.4
0.M47
87.3
0.8308
18.3
0.0038
0.3
0.0001
0.3
k i
^
AQUiB. 249
With the decrease and increase of temperature, tlie specific gravity of aqua
ADimoniaB suffers a corresponding increase or decrease, amounting for each
degree of the centigrade thermometer in either direction —
For aqua ammoniae of a spec. grav. of 0.9001 to that of 0.9221 to about 0.00055
" ** 0 9351 »* 0.9414 »* 0.0004
" ** •» 0.9520 *♦ 0.9670 ** 0.0003
0.9709 '* 0.9831 •* 0.0002
For instance : An aqua ammonise of 0.9593 specific gravity at 14^ C, contain-
ing 10 per cent, of ammonia, will have at 18° C. a specific gravity of 0.9593 —
(0.0003 X 4) = 0.9581, and at 120 C. a specific gravity of 0.9593 + (0.0003 x 2)
s 0.9599.
Rules for the Dilution of Ammonia- Water »
If the amount of ammonia contained in any solution of the
same is greater than desired, and it is required to be diluted witli
water to obtain a certain percentage strength, the same rules and
method of calculation may be employed as directed for hydro-
chloric acid, on page 157. Thus, if the specific gravity of the
ammonia-water at 14° C. is 0.940, it contains 15.4 per cent, of
ammonia, and, if required to be diluted with water so that it shall
contain 10 per cent, of ammonia, the following proportion will l)e
obtained :
15.4 per cent. 10 per cent. 0 per cent.
Difference 5.4 10
Thus, 10 parts of the 15.4 per cent, ammonia are to be mixed
with 5.4 parts of water, for
100 grams Ammonia-water » 15.4 grams NH,
54 " water «
154 grams Ammonia- water -■ 15.4 grams NII3
or 100 ** ** " « 10.0 "
AQUA AMTGDAL^I AMAR2I.
AQUA AMYGDALARUM AMARARUM.
Bitter- Almond Water.
Ger. Bittermandelwasser ; Fr. Eau d^nmandes ameres ; Sp. Agua
de almendra amarga.
Bitter-almond water, when prepared from the essential oil of
bitter almonds, is a clear, when derived by distillation from bitter
almonds, mostly a slightly opalescent, colorless liquid, with the
odor of oil of bitter almonds, which odor must not disappear
after the elimination of the hydrocyanic acid by argentic nitrate.
The preparation of the U. S. Pharmacopoeia contains one part
250 MANUAL OF CHBMICAL ANALYSIS.
of bitter almond oil in 1000 parts of water; that of the Pharm.
German., one part of absolute hydrocyanic acid in 1000 parts of
the product (corresponding to one-tenth of 1 per cent.), which is
associated in the water, containing a little alcohol, with benssoic
aldehvde.
Argentic nitrate and mercurous nitrate produce but a slight
turbidity in bitter-almond water ; but, when a few drops of ammo-
nia-water have been previously added, and the liquid is then
supersaturated with diluted nitric acid, argentic nitrate will yield
a white precipitate of argentic cyanide, and mercurous nitrate,
upon warming, a dark-gray precipitate of metallic mercury, while
mercuric cyanide will remain in solution.
Ferrous salts produce no direct reaction with bitter-almond
water; if, however, a few drops of a solution of an alkaline hydrate
are first added, then a little of a solution of an oxidized ferrous
salt, and the solution subsequently slightly supersaturated with
hydrochloric acid, a deep blue coloration will be produced, and,
upon standing, a precipitate of Prussian blue will be deposited.
Examination :
Nitrohenzol (essence of mirbane), or so-called artificial oil of
hitter almonds, when employed as a substitute for the bitter almond
or the true oil in preparing the water, may be readily recognized
by warming the bitter-almond water with a few drops of nitric
acid for several hours, upon the water-bath, when the odor of the
nitrobenzol will still remain perceptible, whereas pure bitter-
almond water will become odorless, in consequence of the vola-
tilization of the hydrocyanic acid, and conversion of the bitter-
almond oil, by oxidation, into odorless benzoic acid.
The further examination of bitter-almond water should be
directed to the determination of the proper amount of contained
hydrocyanic acid, for which the following volumetric method is
convenient and applicable.
Estimation :
Fifty-four grams of the bitter-almond water, or the correspond-
ing amount by volume, if it be measured, is brought into a beaker,
and a few drops of solution of potassium hydrate added, sufficient
to impart an alkaline reaction; if the liquid is opalescent or tur-
bid, a fevy cubic centimeters of alcohol should also be subse-
quently added in order to render it transparent. After the addi-
tion of a few drops of a solution of sodium chloride, to serve as an
indicator, a decinormal solution of argentic nitrate (page 98) is
allowed to flovy in from a burette until, with constant stirring, a
permanent cloudiness of the liquid is just produced. The num-
ber of cubic centimeters of silver solution required for this pur
pose, divided by 100, will give the percentage strength of the
water in hydrocyanic acid. Thus, if 10 cubic centimeters of the
silver solution are employed, the bitter-almond water will con-
tain ^ per cent., or the proper amount of hydrogen cyanide.
AQUJS. 251
If for the above estimation the bitter- almond water be measured,
instead of weighed, its specific gravity should be previously de-
termined in order to ascertain the amount by volume which will
correspond to 54 grams by weight ; for, if it contain alcohol,
which is sometimes added for the purpose of retarding the decom-
position of the hydrocyanic acid, its specific gravity will become
thereby lessened, and in proportion to the amount of alcohol
present. For example, if its specific gravity is 0.98, 54 grams
will correspond to 55.1 cubic centimeters, according to the equa-
tion, 0.98 : 1 BB 54 : 55.1.
AQUA CHLORI.
AQUA CHLORATA. LIQUOR CHLORI.
Chlorine- Water.
Ger. Clilorwasser ; Pr. £hu cliloree ; 8p. Solucion de cloro.
A saturated solution of chlorine gas in distilled water, contain-
ing at 15° C. (59^ F.) 2.8081 times its volume of the gas. The
gas is most soluble in water at 10° C. (50° V.), when the coefficient
of absorption is 2.5852, and above this temperature the solubility
constantly diminishes, until at 100° C. (212° F.) the gas ceases to
be absorbed. If the gas be led into water at temperatures below
10° C. (50° F.), a solid yellow crystalline compound of the gas
with water (chlorine hydrate) is formed, having the composition
CI, + 1011,0. This conipound is readily decom|)osed by expo-
sure to the air into an aqueous solution of chlorine and chlorine
gas, but, when ])reserved in a scaled tube, it may be heated to
88"^ C. (100.4° F.) without decom [position, being resolved at this
temperature into an aqueous solution of the gas and liquid
chlorine.
Chlorine-water has the pale, greenish yellow color, the irri-
tating and suttbcating odor, and the chemical |)roperties of the
gas. When heated, the chlorine becomes completely volatilized,
a change which takes place more gradually by simple exposure
to the air ; by exposure to solar light it undergoes gradual decom-
position with the formation of hydrochloric acid and the elimina-
tion of oxygen, a change which also occurs, but much more
slowly, when chlorine- water is protected from the light.
Chlorine-water destroys instantaneously the color of dilute
indigo-solution, and all vegetable colors. By the strong affinity
of chlorine for all the elements except oxygen, uitrogen, and car-
bon, and for many compound radicals, it is a powerful chemical
agent, and, especially by its j)roperty of abstracting or displacing
hydrogen, bromine, and iodine, from almost all their combinations
by equivalent substitution, a most energetic oxidizer.
MANUAL 0? CHBMICAL ANALYSIS.
An aqueous Holiition of chlorine may be recognized, indepea-
dent of its physical properties, bv ils pnipertv of dissolving gold
lf;if. and by the liberation of iodine from a solution of potassium
ii>dide, which will impart a blue color to mucilage of starch;
when added to a clear solation of barium chloride in sulphuroua
acid, the latter will become oxidized to sulphuric acid, and a white
precipitate of barium sulphate will be immetliately pnxluced.
Chlorine- water should be preserved in small, well-Htoppered
boillcfi, in a cool place, and protected from the light. Bottles of
black glass afford the best protection, although red, yellow, and
green glass exert a similar action, whilst in ves.-*els of blue or vio-
let glass it becomes as speedily decomposed as by exposure to
the direct action of light.
Bumiiiatioii :
Hydrochhrir nciii, resulting from the decom[>osition of the chlo-
rine-water, or from the imperfect wnshing of the chlorine gas,
cannot be directly tested for by means of litmus or argeatic
nitrate, as the former is immediately bleached, and the latter
yields with pure chlorine-water a slight turbidiiy in consequence
of its ready dec*) m position, and the formation of hyp'jchlorous,
chloric, and hydrochloric acids. The presence of hydrochloric aoid
may be readily detected, however, by agitating a portion of the
chlorine- water, in a stopixred vial, with a little metallic inercnry
until iheodorof chlorine has entirely disappeared; the latter then
combines with the mercury to form mercurous chloride (calomel),
whilst the hydrochloric acid remains unchanged, and, after filtra-
tion, may be recognized by its acid reaction upon litmus, and by
the production of a while precipitate of argentic chloride upon
the addition of solution <if argentic nitrate. The loss of the strong
odor of the gas, an acid reaction upon litmus, and the formation
of a white precipitate with argentic tiitrate, when tested after the
above-mentioned treatment with metallic mercury, would indicate
a degree of decomposition which renders the chlorine- *ater unfit
for use.
Inori/anic sails, as an evidence of the employment of spring-
water for the absorption of the gas instead of distilled water, may
be ascertained by a fixed residue remaining upon the evaporation
of ft little of the water on platinum-foil, or on a watch-glass; aa
well as by testing it, after the addition of a little ammonia-water,
with oxalic acid; a while precipitate would prove the presence
of calcium salts, and would be indicative of spriug-waier.
EatlmatioD of Uie Btreogtb of Chlorine-water :
As the value of chlorine-water depends upon the amount of
contained chlorine, which, according to most Pharmacopceias,
should not t>e less than 0,4 per cent, by weight, and, for the sake
of uniformity, should not exceed 0.5 per cent, in maximum
strength, the following methods may be employed for its quantita-
tive DKtimation.
^,
J
AQUJE. 2o3
I. Approximate Estimation:
One hundred parts by weight of chlorine-water are agitated
with a solution of 8 parts of crystallized or granulated ferrous
sulphate (free from peroxide) in 10 parts of a mixture of equal
volumes of water and dilute sulphuric acid. When, now, a few
drops of diluted test-solution of potasvsium permanganate are
added, no discharge of its color should take place. This test
provides for a chlorine-water which shall contain not less than
0.888 per cent, of dissolved chlorine; if it contain a less amount,
the first drc^ps at least of the permanganate solution, which are
added, will become decolorized, as a portion of its oxygen will
then be applied for the oxidation of the excess of ferrous salt,
anli the formation of colorless manganous sulphate. If, on the
other hand, the maximum strength be confined to 0.5 per cent,
of chlorine, the same test may be applied, with the employment,
however, of 4 parts of crystallized ferrous sulphate in dilute acid
solution, which corresponds to O.olO per cent, of free chlorine; if
a greater amount of chlorine is present, it will oxidize a larger
amount of fernnis sulphate, and, if it contain less than 0.51 per
cent., the first few drops of a solution of potassium permangate
which are added will become decolorized.
II. Quantitative Volumetric Estimation :
Among the several methods of volumetric estimation, the fol-
lowing may be recommended for its simplicity, and as affording
accurate results. This method depends upon the property of
chlorine of liberating an equivalent amount of iodine from a solu-
tion of potassium iodide, and of the subsequent conversion of the
iodine by means of a standard solution of sodium hyposulphite
(thiosulphate) into sodium iodide and tetrathionate, as explained
on page 95.
25 grams, or the same number of cubic centimeters, of chlorine-
water are added to 20 cubic centimeters of an aqueous 10 per
cent, solution of potassium iodide, contained in a flask or beaker,
and the whole well mixed by stirring with a glass rod. A stan-
dard solution of sodium h^^posulphite (page 94) is then allowed
to flow in from a burette, until a sliglit excess has been em-
ployed, and complete decoloration is effected; to the solution
a little mucilage of starch is then added, and the liquid subse-
quently inversely titrated with a standard solution of iodine
(page 98) until, with constant stirring, a ]>ermanent blue colora-
tion is just produced. If, for example, *^i^.h cubic centimeters of
sodium hyposulphite solution were fir.st employed, and subse-
quently 2.8 cubic centimeters of standard iodine solution, then
88.5 — 2.8 « 80.7 cubic centimeters of sodium hyposulphite solu-
tion, or the amount required for combination with the liberated
iodine. Accepting the h^'posulphite solution to be of such a strength
that 1 cubic centimeter corresponds to 0.012818 gram of iodine,
which factor must be established by a previous experiment, as
26^ MANUAL OF CHEMICAL ANALYSTS.
explained on page 95, then 30.7 X 0.012318 - 0.3781 grann of
iodine, which, according to the equation —
127 : 35.5 - 0.3781 : 0.10435,
corresponds to 0.10435 gram of chlorine, and, as this is contained
in 25 grams of chlorine-water, the percentage strength of the
latter would be, in the instance quoted, 0.417 per cent.
The U, S. Pliarmacopoeia requires that on mixing 35.4 grams
of chlorine- water with a solution of 0.9 gram of potassium itxlide
in 20 grams of water, the resulting deep red liquid should require
for complete decoloration at least 40 cubic centimeters of the
volumetric solution of sodium hyposulphite (corresponding to at
least 0.4 per cent, of chlorine).
AQUA DB8TILLATA.
Distilled Water,
Ger. DeAttllirtes Wasser ; Fr. Eau destillee ; Sp. Agua dcstilada.
H,0; 18.
An insipid, transparent and colorless, odorless liquid, which,
under a pressure of 760 millimeters, boils at 100*^ C. (212^ F.),
but evaporates slowly at ordinary temperatures, and, at 0^ C.
(32-^ F.), solidifies in the form of ice, in crystals of the hexagonal
system. Its greatest density is. at 4^ C. (39.2^ F.). If, however,
its expansion is prevented, it retains the liquid form even at — 24"^
C.(---11.2M^).
Water is an almost incompressible fluid, one million volumes
becoming less by fifty volumes when the atmospheric pressure is
doubled ; it is a bad conductor of heat, and a still worse conductor
of electricity. Pure water, from the fact of being a simple solvent
for a large class of bodies, is the most valuable and indispensable
chemical agent, and should respond to the following tests of
purity.
Distilled water must not leave a fixed residue upon evaporation.
Wheu reduced by evaporation to one-fourth or one-sixth of its
volume, and then tested in separate })ortions with lime-water for
cnrljonates^ with argentic nitrate and a few drops of nitric acid for
chlorides, with barium nitrate for sal/fhatrs, with ammonium oxa-
late for calciuifiy and, after acidulation with hydrochloric acid, as
also after suV)sequent supersatu ration with ammonia- water, with
hydrogen sulphide for metals^ it must in no instance yield any
reaction.
Ammonia or ammonium salts may be detected by the addition
of a few drops of Nesslers reagent (page 40) or of Bohlig's reagent
(page 39); a brown coloratio.i or turbidity with the first men-
AQVJR. 255
tioned reagent, and a white turbidity with the latter, due to tlie
formation of a compound of niercur-ammonium chloride with
mercuric oxide, N -j jt* Cl.HgO, will reveal the presence of
ammonia.
Nitrons add may be detected by mixing in a beaker a little
mucilage of starch, acidulated with sulphuric acid, with a solution
of potassium iodide; the mixture must remain colorless; the
water under examination is then added, stirring it with a glass
rod ; if the liquid assumes a bluish tint, traces of nitrous acid are
indicated.
Nitric acid ma}' be detected by reducing a portion of the water
by evaporation to about -^ of its volume, and to the liquid, con
tained in a test-tube, subsequently adding a few drops of solution
of aniline sulphate, and, afterward, about 10 drops of concentrated
sulphuric acid; the liquid is then slowly stirred with a glass rod,
when, if nitric acid be present, rose-colored lines will appear after
a while, and the whole liquid also will gradually assume this tint.
Nitric acid may also be tested for by adding to about 100 cubic
centimeters of the water, 2 or 3 drops of i)ure concentrated sul-
phuric acid, a few fragments of metallic zinc, and a little mucilage
of starch, together with a few drops of a solution of potassium
iodide ; if nitric acid or nitrates are present, they will become
therebv reduced to nitrous acid, which will liberate iodine from
the solution of potassiuin iodide, and impart a blue coloration to
the starch.
Oryanic sulstances may be recognized in the water, if it is free
from nitrous acid, by warming to near 60° C. (140° F.) a portion
of the water in a beaker, which is then placed upon white paper;
then a few drops of sulphuric acid, and subsequently a very dilute
solution of potassium permanganate (1 : 1000), are added, drop by
drop. If the water is entirely free from organic substances, it
should assume and retain, upon the addition of the first drop of
the solution, a slight rose-colored hue, which increases in intensity
progressively with the number of drops added. If the water,
however, contains organic substances, the coloration received
from the first drop will either not appear at all, or will soon dis-
appear.
If decoloration takes place, an approximate estimate of the
quantity of organic substances contained in the v\'ater maybe had
from the number of drops which it is necessary to use before this
effect ceases, and the permanent color begins to appear.
This same decoloration is also produced when the water con-
tains certain inorganic substances, as nitrous and sulphurous
acids, hydrogen sulphide, ferrous, and other sub-salts, and other
readily oxidizable substances. Organic matter in combination with
the above-mentioned substances may, however, be recognized by
evaporating a considerable quantity of the water by the aid of a
256
AL OF CHEMICAL A.VALTSIS.
gentle heat to dryness, and finally strongly beating the residue in
a porcelahi or platinum crucible. If a brown or blackish colora-
tion is thereby produced, the presence of organic matter is indi-
cated, and, if the latter contains nitrogen, an odor resembling that
uf imrnl hair will be also at the same time developed.
AHGENTI CYANIDUM.
ARGENTLM CYANATUM.
Cyanidt of Silptr. ArgeMie CpiHidi.
Ger. CynnBilber; Fr. Cyanitre d'nrgent ; St>. Cinnum de plnla.
AgCN; 133.7.
A white, amorphous powder, which hecomes but slowly dis-
colored by exposure to light (distinction from argentic uhloride).
When strongly heated, the salt fuses and becomes decomposed,
with the development of cyanogen gas, leaving finally a grayish
residue, consisting of metallic silver and argentic paracyanide.
Argentic cyanide is insoluble in water, alcohol, and the dilute
mineral acids, but is soluble in a solution of sodium hy|K>su]phite
or ammonia-waler. and from the latter solution, upon su|)cr3iitu-
ration with nitric acid, it ia precipitated unchanged.
When heated with an excess of concentrated nitric acid, it is
partially dissolved, but is again precipitated on cooling; by pro-
longed heating with the acid it becomes decoin[)osed, ana is
finally entirely dissolved. When boiled with a mixture of equal
parts of concentrated sulphuric acid and water, it is decomposed,
with the development of hydrocyanic acid and the formation of
argentic sulphate, and can thus be separated from argcnlic chlo-
ride. By the action of hydrochloric acid, even in the cold, it is
readily converted into argentic chloride, and. in the liquid filtered
therefrom, the hydrocyanic acid may be readily detected by nen-
traliKation with ammonia-water, addition of a few drops of a solu-
tion of a ferric and ferrous salt, or partially oxidised ferrous sul-
phate, and subsequent supersalnration with hydrochloric acid,
when a precipitate of Prussian blue will l>e produced. When
digested with a solution of vellow ammonium sulphide, it is
converted into argentic sulphide, and if the liquid filtered there-
from, which contains ammonium sulphocyanide, be cautiously
evaporated to dryness, the residue dissolved in water, filtered,
and, after acidulating with hydrochloric acid, tested with a few
drops of a solution of ferric chloride, a deep blood-red color will
be produced.
Argentic cyanide has a great tendency to enter into combina-
tion with the alkaline cyanides, with the formation uf readily
^
AROfiNTUM. 257
soluble and crystallizable double salts. Thus with potassium cya-
nide, it forms polassio- argentic cyanide AgK(CN)„ which may be
obtained by the evaporation of its solution in colorless, hexagonal
tables, soluble in 4 parts of water at ordinary temperatures, and
also soluble in alcohol ; with sodium cyanide it forms 5oc//o-arycn-
tic cyanide^ AgNa(CN)j, which crystallizes by the evaporation of
its solution in colorless laminae, soluble in 5 parts of water, and
also readily soluble in alcohol. From the solutions of both of
these salts, the argentic cyanide is again precipitated upon the
addition of a mineral acid, with the liberation of hydrocyanic
acid..
ARaBNTI lODIDUM.
ARGENTUM lODATUM.
Iodide of Silver. Argentic Iodide.
Ger. Jodsilber ; Fr. lodure d^argent ; 8p. loduro de plata.
Agl; 234.8.
An amorphous powder, of a light-yellowish color, and having
the specific gravity of 5.807 at 0^ C. (32° F.). When perfectly
pure, it undergoes no change by exposure to solar light, but, as
prepared by precipitation from a solution of argentic nitrate, it
usually contains traces of the latter salt, and then assumes on ex-
posure to the light a greenish or grayish-black color. It melts at
a dull red heat, without decomposition, forming a yellow liquid,
which, on further heating, assumes a red, and finally a dark red-
dish-brown color, and, on cooling, solidifies to a soft yellowish
mass, which has then the specific gravity of 5.687 at 0^ C.
(32° F.).
When argentic iodide is gently heated in chlorine gas, it is con-
verted into argentic chloride, with the liberation of iodine; the
same decomposition is effected when an excess of the salt is agi-
tated with concentrated chlorine-water, and the filtered liquid
will then assume a blue color on the addition of a little mucilage
of starch.
Argentic iodide is insoluble in water, alcohol, diluted acids, or
solution of ammonium carbonate, and is almost insoluble in strong
ammonia-water, spec. grav. 0.890, one part of the salt requiring
of the latter 2493 parts for solution (distinction from argentic chlo-
ride and bromide). It is quite readily soluble in a solution of
sodium hyposulphite (thiosulphate), although less freely then ar-
gentic chloride; and is soluble in a concentrated solution of potas-
sium iodide, being re- precipitated, however, on the addition of
water. It is also dissolved by an aqueous solution of potassium
ass MANUAL OP CHEMICAL ANALYSIS.
cyanide, aiiii the resulting solution yields a black precipitate with
liydrogen sulphide or ammonium sulphide.
If a small portion oF the salt be digested with a concentrated
solution of ammonium carbonate, filtered, and the filtrate slightly
supersaturated with nitric acid, not more than a alight opalesoenoe
should be produced; a white turbidity or precipitate would indi-
cate a contamination with argentic chloride.
AROBNTI NXTRAS.
ARGENTUM NITIIICUM.
A'ilrale of Bitter. Argtntie NUraU.
Ger. 8alpeler
AgNO,; 1G9.7.
Anhydrous, colorless, transparent, rhombic crystals (Fig.
or, when fused and cast into moulds, thin, white, transparent,
cylindrical sticks. Argentic nitrate, when
Fio. M. perfectly pure, is not altered by expo-
sure to light and air, but, in contact with
organic matter, becomes rapidly black-
ened by expOHiire to the light. Its spe-
cific gravity is 4.328. When heated to
198° C. (3S8.4° F.), it melts without de-
composition, forming a pale yellowish-
colored liquid, which solidifies on cooling
to a white fibrous crystalline mass; at a
higher temperature it is partially decomposed with the formation
of some argentic nitrite and oxide, which impart an alkaline
reaction to the salt, and, at a red heat, further decomposition
ensues, with the development of oxygen, nitrogen, and nitrogen
dioxide vapors, leaving a residue of metallic silver. When fused
upon charcoal before tlie blow-pipe, it deflagrates, emitting yellow
vapors and sparks, while a reticular coating of metallic' silver
remains behind.
Argentic nitrate is soluble in 0.8 part of water and in 26 parts
of alcohol at 15^ C. (59° F.), and in 0.1 part of boiling water and
5 parts of boiling alcohol, but is only sparingly soluble in ether
and chloroform; its strong aqueous solution, therefore, when
dropi>ed into alcohol, sutlers no precipitation.
The aqueous solution of argentic nitrate must be clear, and
perfectly neutral in its action upon litmus; a while turbidity
would indicate argentic chloride or nitrite; a bluish color, cupno
nitrate ; a grayish-black turbidity in the solution of the fused salt,
a partial reduction by an excess of heat in the fusion, op cuprio
chloride or oxide.
ARoaNTUu. 259
The Bolulion yields, with hydrochloric acid or soluble chlorides,
a white, curdy precipitate of argentic chloride; with hydrogen
sulphide, a brownish-black precipitate of argentic sulphide ; with
the alkaline hydrates a grayish-brown precipitate of argentie
oxide, readily soluble in ammonia- water; with the alkaline car-
bonates, a pale yellow precipitate of argentic carbonate; with
sodium phosphate, a bright yellow precipitate of argentic phos-
phate; and with potassium chromate, a brownish-red precipitate
of argentic chromate, all of which are soluble in nitric acid or
ammonia-water. From a solution of argentic nitrate many of the
metals eft'ecl the separation of metallic silver; such are lead, tin,
cadmium, zinc, copper, mercury, and also bismuth, arsenic, and
antimony.
Examination:
In the employment of argentic nitrate for surgical, ophthalmic,
and similar purposes, it is desirable to overcome its brittle pro-
perties, and to impart thereto greater solidity, or to modify to sonic
extent its action. This is attained by fusing the argentic nitrate
with definite pro|x)rtion8 of argentic chloride or potassium nitrate,
and such admixtures are ofRcinal in some pharmacopceias, Arf/enti
yitras I^usus, and Ar'jenti Nitras DilnHis, U. S. P.; the former
containing about 5 per cent, of argentic chloride, and the tatter
50 per cent, of potassium nitrate. The Arf/enlum nilr/cum cum
kali nitrico of the Pharm. German, is a mixture obtained by
fusing 1 part of argentic nitrate with 2 parts of potassium nitrate.
Such admixtures are indicated in the fused silver salt, by an
alteration of its appearance, which is less translucent, whiter, and
without the distinct radiate crystalline structure of pure argentic
nitrate.
Among the methods of delecting such admixtures, the follow-
ing are the readiest and most practicable ones:
Potasiium Nitrate. — 1. A concentrated aqueous solution of
argentic nitrate is dropped into ten times its bulk of strong alco-
hol; if potassium nitrale be present, it will separate after a while
in small, white granules, as it is far leas soluble in alcohol.
Sodium nitrate, which, however, on account of its hygroscopic
character, is not adapted to this purpose, cannot be detected by
tbia test, since it is more soluble in alcohol.
2. A small quantity of a dilute solution of argentic nitrate is
completely precipitated with diluted hydrochloric acid ; the liquid
is then warmed, and must, in the case of pure argentic nitrate,
when filtered, leave uo fixed residue upon evaporation ; such a
residue would indicate alkaline nitrates or other impurities, the
amount of which may be quantitatively estimated by repeated
evaporation with a little dilute nitric acid, finally drying the
residue at 100^ C. (212"^ F.), and determining its weight, or
by ascertaining the amount of dry argentic chloride which is
yielded by a weighed amount of the salt.
2li0 MANUAL OF CHEMICAL ANALYSIS.
3, A number of larger and smaller cryatals are m
brokon in a mortar; a small portion of the coarser powder, or
fused argentic uilrute. if this be tested, is fused and completely
reduced on charcoal before the blow-piiie (Fig. 97): a slight re-
ticular metallic coating will
Fio. 07. remain behind, and some
alkaline carbonate, if potas-
sium or sodium nitrates
were present; they will be
recognized by the alkaline
reaction, when moist, red
litmus-paper is pressed upon
the spot of the coal where
the fusion took place.
Art/enlic chloride is indi-
cated, as stated, by a white
turbidity of the solution of
argentic nitrate; itsidentity
may be ascertained by its dissolving upon the addition of am-
monia-water, but remaining insoluble in nitric acid.
Copper and iron may be detected by completely precipitating
the aqueous solution of the salt with hydrochloric acid, and by
subsequent approximate neutralization of the filtrate with am-
monia-water; this solution is then tested with a few drops of
a solution of potassium ferrooyanide ; a red precipitate would
indicate copper, a blue one, iron ; copper may also be detected,
or its presence confirmed, by dissolving a small quantity of the
argentic nitrate in a little water, in a test-tube, and subsequently
adding to the solution a few drops of ammonia- water ; an ensuing
blue coloration would indicate copper ; a white turbidity, lead or
ziac, which, in the case of zinc, disappears upon the addition of
an excess of ammonia- water.
Lead and bismulh, as also foreign metala in general, may be
detected by completely precipitating the silver from the aqueous
solution of the argentic nitrate by means of hydrochloric acid,
washing the precipitate well with water, subsequ^sntly testing the
filtrate with hydrogen sulphide, and, after again tillering, if neces-
sary, and supersaturating with ammonia- water, testing with ammo-
nium sulphide ; a coloration or precipitate in either case will indi-
cate contamination with foreign metals. Lead may also be specially
tested for by adding to a solution of 1 part of argentic nitrate in
10 parts of water, 4 times its volume of dilute sulphuric acid;
a white precipitate will indicate the presence of lead.
Nitrous acid or iir</eiUic nitrite, traces of which are frequently
met with in the fused argentic nitrate, and which are more cou-
siderable in amount in proportion to the extent of the admixture
with potassium nitrate, will be indicated by a slight turbidity
upon dissolving the salt in water, and readily recognized as fol-
ARGBNTUM. 261
lows : A dilute solution of the salt is completely precipitated by
the addition of a slight excess of hydrochloric acid, rapidly filterea,
and the filtrate added to a solution of potassium iodide, contain-
ing a little mucilage of starch ; if nitrous acid be present, a blue
coloration will be immediately produced.
Estimation:
The determination of the purity of crystallized argentic nitrate,
as also the amount of the latter salt when associated with argentic
chloride, potassium nitrate, or other substances which may be
used as admixtures or for the purpose of adulteration, may be
readily accomplished either gravimetrically or by the method of
volumetric analysis.
I. Gravimetric, — One gram of the salt is dissolved in a small
amount of water, the solution filtered, if necessary, and hydro-
chloric acid subsequently added until a precipitate ceases to be
produced; the precipitate is collected upon a tared filter, tho-
roughly washed with water, and finally dried at 100° C. (212® F.)
until of constant weight. If the salt be pure argentic nitrate, the
precipitate of argentic chloride thus obtained will weigh 0.8441
gram ; if it be argenti nitras fusus^ it will weigh 0.801 gram, and
if argenti nitras dilutus^ 0.422 gram, respectively.
II. Volumetric. — About 0.5 gram of the salt is dissolved, in a
beaker, in about 20 cubic centimeters of water, a few drops of a
solution of potassium chromate added, and subsequently a deci-
normal solution of pure sodium chloride (containing 5.85 grams
of the dry, crystallized salt in 1 liter) allowed to flow into the
liquid from a burette until, with constant stirring, the red colora-
tion of argentic chromate remains permanent.
One cubic centimeter of the decmormal sodium chloride solu-
tion corresponding to 0.017 gram of pure argentic nitrate, this
number, when multiplied by the number of cubic centimeters
employed, will indicate the amount of pure argentic nitrate in
the specimen under examination.
ARaSNTI OXIDUM.
ARGENTUM OXYDATUM.
Oxide of Silver. Argentic Oxide,
Ger. Silberoxyd ; Fr. Oxyde d'argent ; Sp. Oxido de plata.
Ag,0; 231.4.
An olive-brown, amorphous, odorless powder, which, when
heated at a temperature of from 60 to 80° C. (140-176° F.),
becomes almost black ; at 250® C. (482° F.) it begins to decom-
pose, and at 300° 0. (572^ F.) it loses the whole of its oxygen,
2fii MANTAL OF OUBMIGAL ANALYSIS.
leaving beliind spongy inetailic silver; it is also gradually re-
duced by solar light.
Argentic oxide is sparingly soluble in water, one part requiring
about 30O0 parts for solution, but is freely dissolved by ammonia-
water, as also by warm, concentrated nitric and sulphuric acids;
it is insoluble, however, in the li.\ed alkaline hydrates. Its aque-
ous solution has an alkaline reaction and a metallic taste, and la
rendered turbid by a small quantity of carbon dioxide, but
becomes clear again upon the absorption of a larger quantity of
the gas. When argentic oxide is triturated in a mortar with the
sulphide of arsenic or antimony, finely divided sulphur, amor-
phous phosphorus, tannic acid, and many otiier readily oxidizable
substances, ignition takes place.
The purity of argentic oxide is ascertained by its solubility in
ammonia -water, and also in hot nitric acid, without effervescence,
and by the fact that the latter solution, when completely precipi-
tated with hydrochloric acid, gives a filtrate which leaves no
residue upon evaporation, and yields no reaction with hydrogen
sulphide, either in the acid solution, or on subsequent supcrsatu-
ratioQ with ammonia-water. One gfiim of argentic oxiae wheu
dissolved in nitric acid, the solution evaporated, diluted with
water, if necessary, and subsequently completely precipitated by
hydrochloric acid, yields a precipit-iile of argentic chloride, whiob,
when washed and dried, should weigh 1.236 grams.
ARamm bromiditm.
ARSENICUM BROMATUM.
Bromida of Arunic. Anenieut Bromide. Arienic Trihromiit, '
Ger. &r«ent)romar ; Fr. Bromure d'arscnlc ; Sp. Bromuro dc ars^nlon.
AsBr,; 314.3.
Colorless, prismatic crystals, which possess a peculiar (arsen-
ical) odor, and deliquesce upon exposure to the air. The salt
haB a specific gravity of 3,66. It melts at from 20 to 25° C.
(68-77'' F.), boils at 220° C. (428"^ V), and is completely vola-
tilizable by heat. Arsenious bromide is miscible with a small
amount of water, forming a clear solution, from which, upon
standing, arsenic oxybromide, As(On),Br, is separated; in con-
tact with a larger amount of water, it is decompased with the
formation of arsenious and hydrobromic acids. lu aqueous solu-
tion, when saturated with hydrogen sulphide, yields a yellow
precipitate of arsenic trisulphide; and when heated with diluted
nitric acid, it is decomposed with the liberation of bromine, which
dissolves, upon agitation with a few drops of chloroform or car-
bon bisulphide, with a yellowish or reddish-browit color.
ARSENICUM. 268
AR8BNII lODIDUM.
ARSENICUM lODATUM.
Iodide of Ansnic. Anenious Iodide, Arsenic Triiodide.
Ger. Arsenjodiir ; Fr. lodure d'arsenic ; 8p. loduro de ars^mco.
Aslj; 454.7.
An orange-red or purple, crystalline solid, or bright red, shining,
hexagonal tables, gradually losing iodine on exposure to the air,
and possessing an iodine-like odor and taste. Its specific gravity
is 4.39. When gently heated, the salt fuses, and may he sublimed
without decomposition; when stronjgly heated, it is completely
volatilized.
Arsenious iodide is soluble in 3.5 parts of water and in 10
partii of alcohol at 15° C. (59^ F.), but is decomposed by boiling
water into arsenious and hydriodic acids; it is also soluble in
glycerin, ether, and carbon bisulphide, and crystallizes from the
latter solutions upon evaporation unchanged. From its solution
in a relatively small amount of water, upon standing, a compound
consisting of arsenic trioxide with arsenic oxyiodide, As(OH)J,
is separated, which crystallizes in bright yellow, shining, crystal-
line laminae.
The aqueous solution of arsenious iodide is of a yellow color,
and when saturated with hydrogen sulphide yields a bright yel-
low precipitate of arsenic trisulphide; when heated with diluted
nitric acid, it is decomposed with the liberation of iodine, which
dissolves, upon agitation with a few drops of chloroform or carbon
bisulphide, with a reddish -violet or purple color.
ATROFINA.
ATROPINUM.
Atropine. Atropia.
Ger. Atropin ; Pr. Atropine ; 8p. Atropina*
C„H„NO,; 289.
Colorless, silky, acicular crystals, or a yellowish-white crystal-
line powder, without odor, and of a bitter and acrid taste.
When carefully dried, the crystals melt at 112° C. (233.6^ F.),
and by very cautiously heating, in small amounts, may be partially
sublimed ; upon more strongly heating they become decomposed
with the development of ammonia, swelling and emitting inflam-
mable vapors, and leaving a carbonaceous residue, which is wholly
dissipated at a red heat.
NITAL OF CUEMICA
Atropine is soluble in 600 parls of water at 15° C, (59° F.),
in 36 parts of boiling water, in 60 parts of ether, in 3 parts of
chloroform, freely in alcohol and amylic alcohol, and is also solu-
ble in glycerin, but is very sparingly soluble in carbon bisulphide.
The aqueous solution possesaea a purely bitter taste, without
acridity, a strongly alkaline reaction, and powerfully dilates the
pupil of the eye.
Atropine dissolves in concentrated nitric acid, imparting to it a
yellowish color, and in eold concentrated sulphuric acid, without
color, but, upon warming, the solution becomes reddish-brown,
develops an odor resembling that of orange flowers, particularly
upon the addition of a little water, and becomes finally blacK.
The solution in cold concentrated sulphuric acid is not colored
upon the addition of nitric acid (distinction from morphine and
hrucine), nor at once by solution of potassium bichromate (dis-
tinction from strychnine), but gradually assumes with the latter a
green coloration, and, upon warming, the odor of oil of bitter
atmonds is evolved ; the same odor is developed when, instead of
potassium bichromate, potassium permanganate, manganese diox-
ide, or ammonium molybdale is employed. The aqueous solution
of atropine or its salts yields precipitates with moat of the ordi-
nary alkaloidal reagenta, but is not precipitated by picric acid
(distinction from daturinf), nor by platinic chloride, unless very
concentrated (distinction from hyoscyamine and Mladonnine); the
latter is also distinguished by its amorphous character, and by \Xa
insolubility in a boiling solution of barium hydrate.
Atropine and its salts are decomposed and rendered inert by
prolonged contact with potassium or sodium hydrate, and, when
heated with either of the latter, vapors of ammonia are evolved.
An aqueous solution of atropine or its salts also undergoes gradual
decomposition at ordinary temperatures.
When atropine is heated at from 120 to l-iO'^ C. (248 to 284" F.)
with concentrated hydrochloric acid, or with a concentrated solu-
tion of barium hydrate, it is resolved by assimilation of a mole-
cule of water into a crystallizable base, tropine, OjH„NO, which
is readily soluble in water, alcohol, and ether, and iropic acid,
C,H„0,(phenylhydracylicacid,C,H.-CH(^^Q^^), which crys-
tallizes in small colorless prisms, quite readily soluble in water,
and freely iu alcohol and ether.
C„II„NO, + H.O = C,H„NO + C,H„0,
Atropine. Tropine. Tropic add.
Tropic acid, by further treatment with the above- mentioned
reagents, is resolved by the loss of a molecule of water into
>tlrf>pic and iaatrapic nci<U, both of which have the compoaitioQ
C,H,0„ and are therefore isomeric with cimiamic acid.
ATROPIMA. 265
C,H,.0, — H,0 - C.H.O,
Tropic acid. Atropicacid.
Isatropic acid.
Atropic acid, by oxidatioa with a solution of potassium bichro-
mate in dilute sulphuric acid, is further converted into benzoic
addj with the evolution of carbon dioxide:
CqH.O, + 50 - H,0 + 200, -h 0,H,0,
•-V
Atropic acid. Benzoic acid.
When melted with potassium hydrate, it yields alphatoluylic
acid, CgHgO,, together with formic acid: and, upon heating with
faming hydrochloric acid, it is converted into isatropic acid.
For the separation of atropine from other alkaloids, or when
associated with complex organic mixtures, see page 108.
ATROFIN2I SULPHAS.
ATROPINUM SULPURICUM.
Sulphate of Atropine or Atropia. Atropine Sulphate.
Ger. Atropinsulfat ; Fr. Sulfate d*atropine ; Sp. Sulfate de atropina.
(C„H^NO,)..H.SO, ; 676.
A colorless, indistinctly crystalline powder, permanent in the
air, without odor, but possessing an unpleasant, bitter taste.
When heated to 180° 0. (356^ F.) it fuses, and when more strongly
heated upon platinum-foil, it is decomposed with the evolution of
acrid vapors, leaving a carbonaceous residue, which is finally
wholly dissipated at a red heat. It gives the same reactions as
atropine with concentrated nitric and sulphuric acids, and, in the
latter solution, with potassium bichromate or permanganate, and
other oxidizing agents.
Atropine sulphate is soluble in half its weight of water at 15° C.
(59° F.), in 2.6 parts of alcohol, spec. grav. 0.835, in 0.3 part of
absolute alcohol, and very freely soluble in boiling water and boil-
ing alcohol ; it is very sparingly soluble in amy lie alcohol, ether,
chloroform, and carbon bisulphide. Its aqueous solution is neutral
in its action upon litmus, and yields with a solution of barium chlo-
ride a white precipitate of barium sulphate, insoluble in nitric acid.
From its concentrated aqueous solution, potassium or sodium
hydrates, ammonia-water, and sodium carbonate precipitate the
pure alkaloid, which is soluble in an excess of the solutions of
the alkaline hydrates, as also in a large amount of water. In
other respects, atropine sulphate shows the same behavior towards
266 MANUAL <JP CHEMICAL ANALYSIS.
reagents as atropine, and, like the latter, when applied to tlie eye,
even in very dilute solution, produces dilation of the pupil.
The aqueous solation of atropine sulphate, acidulated with sul-
phuric acid, should afford no precipitate upon the addition of a
solution of picric acid ; the formation of a precipitate with the
latter reagent will indicate the presence of daturine.
AURI HT SODII CHLORIDUU.
AURO-NATRIUM CHF.ORATUM.
Chloridi of Ooid and Sodiui
Ger. Nat
Sodium Chlor-aurale.
•X de todium ;
AiiCl,.NaCl + 2H,0;
6.8.
The double chloride of gold and srwiiura forms large yellowisli-
red rhombic tables or prisms, coutaining 2 mnlecuies (9.04 per
cent.) of water of crystallization. As ofBcinal in the United
States and German Pharmacopiceias, however, a considerably larger
amount of .sodium chloride is employed than ia required for the
formation of a double salt of the ab()ve compositiou ; the prepara-
tion consisting of a mixture of equal parts of the anhydrous
chlorides of gold and sodium, corresponding to 32.4 per cent, of
metallic gold, whereas the pure crystallized double salt contains
76.25 per cent, of auric chloride, or 49.49 per cent, of metallic
gold. The officinal preparation, like the pure double salt, is of a
yellow color, deliquescent upon exposure to the air, and, in contact
with dust or other organic substances, becomes readily reduced.
It is decomposed at red heat, leaving a residue of metallic gold;
and imparts an intense, persistent yellow color to a non liimiuoua
flame.
Sodium cblor-aurate is freely soluble in water, forming a yel-
low solution of an acid reaction, and imparts to the skin a per-
manent red coloration; it suSers reduction in contact with iDany
organic and inorganic bodies, and, when heated in a test-tube with
a solution of oxalic acid, a light violet colored mirror of metallic
gold is produced.
The solution of auric chloride, upon the addition of ammonta-
waler, yields a brownish-yellow precipitate of ammoniacal aurio
oxide or fulminating gold, Au,0,(NII,)j, which explodes most
violently when in the dry state, either on percussion or when
heated: the solution is not precipitated, however, by potassium
or sodium hydrate, or their carbonates, in consequence of the com-
bination of auric oxfde with the alkali, and the formation of so!u-
ble alkaline auratea. The solutiou of auric chloride, when added
to a solution of potassium iodide, assumes a dark-green color, and
yields a green precipitate of aurio iodide, Aul^ which dissolves
upon agitation in consequence of the formation of soluble potas-
sium iod-aurate ; upon the addition of an excess of the gold solu-
tion, however, a permanent precipitate is produced, which, after
washing, may be dried, but is then quite readily decomposed with
the evolution of iodine, and, upon standing, is converted into
aurous oxide, Au,0. Potassium bromide produces no precipitate
in a solution of auric chloride, the auric bromide being readily
soluble in water. With solution of argentic nitrate it yields a
white, curdy precipitate of argentic chloride, insoluble in nitric
acid, but soluble in ammonia-water.
Hydrogen sulphide produces in a cold solution of aurio chloride
a brownish-black precipitate of aurio diaulphide, Au,S,, which is
soluble in solutions of the alkaline sulphides, ana still more
readily in a solution of potassium cyanide ; from a hot solution of
the chloride, a precipitate of metallic gold is produced.
Examination:
Free acid may be detected by the development of while fumes,
when a glass rod, moistened with ammonia- water, is held over the
surface of the salt.
The further examination of the chloride of gold and sodium
should be directed to the estimation of the amount of contained
gold. About 0.5 gram of the dry salt is accurately weighed, dis-
solved in about 50 cubic centimeters of water in a porcelain cap-
sule, the solution acidulated with sulphuric acid, and subsequently
gently heated for about two hours with a considerable excess of a
clear solution of ferrous sulphate or oxalic acid, The gold is
thereby completely reduced to the metallic state, according to the
reactions expressed by the following equations:
2AnCl, + OFcSO, =• Au, -»- Fe,Cl, + 2Fo,(SO.),.
2AuC]. + 3C,U,0, = Au, + 6KGI -t- tiCO,.
The precipitated cold is finally onllectcd on a filler, thoroughly
washed with water, dried, ignited, and weighed. From the result-
ing weight, the percentage amount of pure gold contained in the
preparation may be readily oalculaled.
If 0.6 gram of the officinal salt be employed for the lest, the
ignited residue should weigh not less than 0.162 gram, correspond-
ing to 'd2.i per cent, of metallic gold.
This hook is the proj''.
COOPER MEDICAL CULL...
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MANUAL OF CHEMtGAL ,
BAKU CHLORIDnU.
BARYUM CHLORATL'M. BARYTA MURIATICA.
Chloride of Barium. Barium Chloride.
Ger. CLlorhftryum ; Fr. Clilorure de liarynra ; Bp. Clomra de bftrio.
BaCl. + 2H,0; 243.6.
Colorless, shining, rhombic tables (Fig. 98), permanent in tbe
air, and having a apecific gravity of 3.05 at 4° C. (39.2° F.). They
contaiu two molecules (l-i.75 percent.) of water of crystallization,
which are eliminated at a temperature of 113° C. (235.4** F.), form-
ing a white powder, which fuses at a
Fio. 08. red Iieat,and imparts a yellowish-green
color to ihe flame. By exposure to the
airduringthe process of fusion, it loses
a small amount of chlorine, with the for-
mation of a little barium oxide, which
imparts an alkaline reaction to the
fused salt.
Barium chloride is soluble in2.3partsof water at 15' 0.(59*' F.),
and in l.S parts of boiling water; it is insoluble in absolute or
strong alcohol, but is sparingly dissolved by dilute alcohol, and in
an amount proportionate to the quantity of water present. It is
lees soluble in diluted hydrochloric and nitric acids than in water,
and is therefore partly precipitated from its aqueous solution, if
not verv dilute, upon the addition of concentrated hydrochloric
or nitric acids, in the latter case with the formation of barium
nitrate; the salt is, however, redissolved upon dilution with
water. The aqueous solution has a bitter, nauseous, saline tikite,
is neutral in its action upon litmus, and yields copious white pre-
cipitates with sulphuric acid and sulphates, and with argentic
nitrate, insoluble in diluted nitric acid; the latter precipitate being
soluVe in ammonia-water. With the soluble carbonates, phos-
phates, and chromates, precipitates of the respective barium salts
are produced, all of which are soluble in hydrochloric and nitric
acids.
Examination :
Aluminium may be detected, in the dilute aqueous solution, bv
a white turbidity on the addition of ammonia- water; a bluish
coloration of the liquid would indicate copper.
Metals will be detected by & dark precipitate, or, if only traces
of iron are present, by a dark-greenish coloration, upon the addi-
tion of ammonium sulphide to the aqueous solution ; if a precipi-
tate be formed, it is collected upon a filter, washed with water,
dissolved in a few drops of warm nitric acid, and the solution
supersaturated with ammonia-water; a blue coloration would con-
firm tiie presence of copper; a brown precipitate that of iron.
BBNZINUM. 269
Calcium^ potassium^ and sodium chlorides^ are detected, in the
aqueous solution, by completely precipitating the barium with
diluted sulphuric acid, and by subsequent examination of the
filtrate in separate portions; calcium is recognized by a white
precipitate when one of these portions is slightly supersaturated
with ammonia-water, and tested with ammonium oxalate. Potas-
sium and sodium chlorides will be indicated by a fixed residue
upon complete evaporation of another part of the filtrate ; they
may be distinguished by the characteristic flame reactions, or by
dissolving the residue in a few drops of water, and testing the
solution with potassium antimoniate; a white turbidity would
indicate sodium salt.
Strontium chloride is detected by agitating some of the pow-
dered salt with about twenty times its weight of strong alcohol,
filtering, and subsequently igniting the filtrate; the presence of
strontium will be indicated bv a red color of the flame, especially
apparent toward the end of the combustion.
BBNZINUM.
BENZINUM PETROLEI.
Bemin, Petroleum Benzin, Petroleum Ether,
Ger. Benzin ; Fr. Benzine ; Sp. Bensino.
A transparent, colorless, neutral, and highly inflammable liquid,
possessing a characteristic odor, resembling that of petroleum.
Its specific gravity varies from 0.670 to 0.675 at 15° C. (59° F.),
and Its boiling-point from 50 to 60° C. (122 to 140° F.).
Petroleum benzin, as indicated by the boiling-point, is not a
definite body, but consists of a mixture of isomeric and homolo-
gous hydrocarbons of the paraffin series, among which hexUne,
C^H,^, and heptane, 0^11,, .in their different isomeric modifications,
are present in predominating amounts.
It is not miscible with water, and requires about six times its
volume of alcohol, s[>ec. grav. 0.885, for solution, but is miscible
in all proportions with chloroform and ether ; it possesses valu-
able properties as a solvent, dissolving fats, volatile oils, caout-
chouc, and many resins, as also, to a certain extent, some of the
alkaloids and other organic principles, but anhydrous carbolic
acid is insoluble therein (distinction from benzol).
lt¥ainination ;
Heavy hydrocarbons may be detected by a more or less viscid
residue, when a small portion of the benzin is allowed to evapo-
rate spontaneously on d watch-glass, or in a shallow glass or
porcelain capsule.
270 UANUAL OF CHEMICAL ANALYSIS.
Sulphnr eompnuntts aji6 the prodtiefs o/ dJstiUatron of a
may be detected by a brown coloration when a little of the beazia
is mixed, in a test-tube, with one-fourth its volume of an alco-
holic Solution of ammonia, a few drops of solution of argentic
nitrate subsequently added, and the mixture carefully beated fur
a few minutes to boiling; or, by a dark coloration of the liquid,
attended with considerable elevation of temperature, when a email
portion of the benzin is agitated with an equal volume of coW,
concentrated sulphuric acid.
Sulphur compounds may be also detected by boiling a little of
the benzin with a fragment of bright metallic sodium, decantiug
the clear liquid, and, after the careful addition of a little water to
the residue, testing the aqueous liquid with sodium nitro-prue-
side; if sulphur compounds are present, a beautiful violet color-
ation will be produced.
Benzol, a hydrocarbon of the composition CgH,, obtained by the
distillation of coal-tar oil, is tlie body to which the name benzin
was first applied, and is consequently still, by the misapplication
of nnmes, frequently confused with petroleum benzin. It differs
essentially from benziu in its chemical and many of its physical
properties, solidifying at 0° C. (32° F.) to a mass of crystals, which
have the form of rhombic pyramids, and yielding, with half its
volume of alcohol, s[>ec. grav, 0.835, a perfectly clear mixture.
It may be readily detected by mixing, in a test-tube, 40 drops of
concentrated aulphuric acid with 10 drops of pure nitric acid,
subsequently adding to the mixture o drops of the benzin to be
tested, and gently warming; if beuzol is present, the character-
istic odor of nilro-benzol (so-called artificial oil of bitter almonds)
will be produced, which is rendered still more evident by subse-
quently pouring the liquid into a small porcelain capsule, diluting
it with twice its volume of water, and allowing the nitrous acid,
which is formed by the reaction, to evaporate.
Qer, Clli
I Qer
I A white, amorphous powder, without odor or taste, and r
I neot in the air. When heated with exsiccated sodium carbonate,
I on '
I anc
V
BIBHnTHI CITRA8>
BISMUTUM CITRICUM.
(e of Bitmuth. Siimtilhotii Citrate.
ismut ; Fr. Olrale ilc bismuth ; Sp, Cilralo de bismulo,
BiC.H.O,; S99.
>erma-
on charcoal, before the blow pine, it vields brittle metnllic grains,
and, at the same time, a browuish-ye'llow incrustation of the coal
is produced. When heated upon platinum foil, it is decomposed,
BISMTTUUM.
with the separation of carbon, and ibe evolution of empyreumatic
vapors, and, at a red heat, a fused mass remains, wliich, upon
cooUdk, acquires a lemon-yellow color on tlie surface, and which
is readily soluble in warm concentrated nitric acid; this Sdlu-
tion, when dropped into a quantity of water, produces a white
turbidity,
Bismuthous citrate is insoluble in water or alcohol, but is solu-
ble in acids and in ammonia-water. The ammoniacal solution
yields upon saturation with hydrogen sulphide a black precipitate
of bismuth sulphide, and the filtrate therefrom, after being heated,
to expel the excess of hydrogen sulphide, and the addition of a
little lime-water or solution of calcium chloride, and again heat-
ing to boiling, yields a white precipitate of calcium citrate.
Examination:
Chrlionates, Ckhridex, and Sulphates. — A small portion of the
bismuthous citrate is dissolved in dilute nitric acid: if efferves-
cence ensues, carbonates are indicated. The dilute acid solution
is then tested, in separate portions, vith argentic nitrate and
barium chloride, when an ensuing white precipitate will indicate
chlorides or sulphates respectively.
Nitrates may be detected by dissolving a small portion of the salt
in ammonia- water, completely precipitating the bianiuth by hydro-
gen snlphide, filtering, heating to remove the excess of hydrogen
sulphide, and to the clear liquid, contained i[i a test-tube, subse-
quently adding an equal volume of concentrated sulphuric acid,
and afterward a solution of ferrous sulphate, so as to form two
layers (Fig. 99); a violet or brown-colored zone at the line of con-
tact of the two liquids will reveal the presence of nitrates.
MANUAL OF CHEMICAL .
BI8HT7THI ET AMMORH CITRAS.
BISMUTl'M ET AMMONILM CITRICUM.
Cilrale af Bi"aitth and Ammonium. BifmMth and Ammontuin CttfnU.
Get. CitronriiBnuree V iBmut'AmmnDitim \ Pr. Citrnle tie hiemmh
el d'annuDDJatine ; 8p. Cltralo de biBmuto y nmomaca.
Bi(OH)„(NHJ,C,H.O,; 504.
Colorless, glossy, translucent scales, of a slightly aciduloos and
flomcwbat metallic taste. They contam, in acceptance of the cor-
rectness of the above formula, 40.43 per cent, of bismuth trioxide,
Bi Oj. corresponding to 41.66 per cent, of metallic bismuth.
When heated with exsiccated sodium carbonate, upon charcoal,
before the blow-pipe, they yield brittle metallic grains, and, at the
same time, a brownish -yellow incrustation of the coal is pro-
duced; when heated upon platiunm-foil, they are decomposed,
with the separation of carbon, and the evolution of inoisinre and
of ammoniacnl and empyreumatic vapors; and, at a red heat, a
fused mass remains, which, upon cooling, acquires a lemon-yellow
color on the Hurfacc, and which is readily soluble in warm COD-
oentraled nitric acid ) this solution, when dropped into a quantity
of water, produces a white turbidity. The salt, when heated with
a solution of potassium or sodium hydrate, develops the odor of
ammonia.
Bismuth and ammonium citrate is readily soluble in water,
sparingly so in alcohol, and insoluble in ether and chloroform.
By exposure to the air, it loses its transparency, and becomes
gradually more or leas insoluble in water, but is again rendered
soluble by the addition of a little ammonia- water.
Its aqueous solution reddeus blue litmus-paper slightly, gives
white precipitates with dilute hydrochloric ncid (soluble in au
excess of the acid), with potassium hydrate, and with the alkaline
carbonates, the latler precipitates being insoluble in an excess of
the precipitants ; it is not acted upon hy ammonia- water; with
potassium cbromate, it forms a yellow precipitate, soluble in dilute
nitric acid, and, with hydrogen sulphide, a brownish-black pre-
cipitate, insoluble in ammonium sulphide, but readily soluble in
nitric acid. An aqueous solution of the salt, after complete pre-
cipitation with hydrogen sulphide, and subsequent warming lo
expel the excess of the latter, yields, upon the addition of a little
lime-water or solution of calcium chloride, and heating to boiling,
a white precipitate of calcium citrate.
Examination:
Chlorides and sulphates may be detected in the aqueous solution
of the salt, acidulated with nitric acid, by an ensuing white pre-
cipitate, when tested, in separate portions, with argentic nitrate
and barium chloride.
BISMUTHUM. 273
Nitrates may be detected in the aqueous solution of the salt by
mixing it with an equal volume of concentrated sulphuric acid^
and adding a solution of ferrous sulphate, so as to form two
layers (Fig. 99, on page 271) ; a violet or brown colored zone at
the line of contact ot the two liquids will reveal the presence of
nitrates.
BISItfUTHI SUBCARBONAS.
BISMUTUM CARBONICUM.
Carbonate^ Subearbonate^ or Ory-rarhonate of Bismuth. Baste Bismuthous
Carbonate.
Ger. Basiscbes Wismutcarbonat ; Fr. Sous-carbonate de bismutb ;
Sp. Subcarbonato de bismuto.
2(BiO),CO,.H,0 ; 1042.
A white, or pale yellowish-white, odorless and tasteless pow-
der, permanent in the air, and which is blackened when in contact
with hydrogen sulphide.
At iOO° C. (212^ F.) it loses water, and when more strongly
heated it is readily converted intON'-ellow bismuth trioxide, Bi^Oj,
with the elimination of carbonic acid gas: 100 parts of the salt
thus yielding, upon ignition, 89.83 parts of bismuth trioxide, cor-
responding to a loss of 10.17 per cent, of water and carbonic acid
gas. When heated with exsiccated sodium carbonate, on char-
coal before the blow-pi{)e, it yields brittle globules of metallic
bismuth and an incrustation on the coal, which is of an orange
color when hot, and yellow when cold.
Basic bismuthous carbonate is insoluble in water, but slightly
soluble in water saturated with carbonic acid gas; it is readily
soluble, with effervescence, in acids, forming solutions which,
when nearly neutralized by the bismuthous carbonate, produce
white precipitates of very sparingly soluble basic salts when
poured into a quantity of water, and yield upon the addition of
alkaline hydrates a white precipitate of the hydroxide, which is
insoluble in an excess of the precipitant.
Examination:
Nitrate may be detected, in a solution of the carbonate in cold
diluted hydrochloric acid, by the addition of one or two drops of
indigo solution, sufficient to impart to the liquid a slight bluish
tinge, and subsequently heating to boiling; if decoloration of the
liquid ensues, the presence of nitrate is indicated.
Insoluble admixtures may be detected by a residue, when 1 part
of the salt is dissolved, by the aid of a gentle heat, in about 6
parts of a mixture of equal parts of concentrated nitric acid and
water.
18
»A5UAL Of CHEMICAL ANALTStS.
MtluUic Impurities, Chlorides, and Siilj ho' es.~~ The solulion
obtaiued in the preceding teat is poured into 50 parts of water,
filtered from the white precipitate thus produced, the filtrate con-
centrated by evaporation to 6 parts, and subsequently tested as
follows : A portion of the liquid is mixed with 5 times its volume
of diluted sulphuric aeid, when a white cloudiness or precipitate
will indicate the presence of lead: another portion is precipitated
with an excess of ammonia-water, when an ensuing blue colora-
tion of the liquid will reveal the presence of cojiper ; a third por-
tion of the liquid is diluted with five times its volume of water,
and subsequently tested, in separate portions, with hydrochloric
acid for silver, with argentic nitrate for ehlorides, and with barium
nitrate for sulphates, when a white turbidity or precipitate, in-
soluble in nitric acid, will indicate in either ease the respective
impurity.
Alkalies, Alkaline Earths, KaA. Zinc. — A portion of the salt is
dissolved, by the aid of a gentle heat, in diluted hydrochloric
acid; after being allowed to cool, the liquid is filtered, subse-
quently saturated with hydrogen sulphide, and again filtered.
Tlie filtrate thus obtained should leave no residue upon evapora-
tion. If a residue is obtained, it is dissolved in a little water, and
tested with sodium carbonate, when an ensuing white precipitate
will indicate salts of calcium, maguedum, or zinc. In order to
distinguish the latter, the precipitate, if t-ufficient in amount, is
collected and washed upon a filter, dissolved in a little dilute
hydrochloric acid, ammonia-water in slight excess added, and
subsequently tested with ammonium sulphide, when an ensuing
white precipitate will indicate the presence of zinc. The filtrate
from the latter is tested with ammonium carbonate, when a white
precipitate will indicate calcium, and, after filtration and the addi-
tion of solution of sodium phosphate, an ensuing white, crystalline
precipitate will reveal the presence of m(i'jnesi%nn.
The presence or absence of alkalies or alkaline earths in bis-
muthouB carbonate may also be ascertained, by boiling a portion
of the salt for a few minutes with about ten times its weight of
strung acetic acid : the liquid is then filtered, and completely pre-
cipitated with hydrogen sulphide ; the filtrate must leave no fixed
residue upon evaporation; if any such residue remains, alkalies
or alkaline earths are indicated,
CafcfumpAos^AafM may be detected in the residue left by the evap-
oration of the liquid of tfie preceding test, by dissolving it in a little
acetic acid, filtering, if necessary, and testing the solution, in sepa-
rate portions, as follows; To a portion of the solution ammonium
oxalate is added, when a white precipitate will indicate the presence
of calcium; to another portion solution of ammonium molybdatc la
added, and the liquid heated to boiling, when a yellow crystalline
precipitate will indicate the presence of phosphates. The presence
of phosphates may be likewise determined in the solution, which
Fio. 101.
BTSMOTHUM. 275
is first neutralized with am-
monia-water aa completely
as possible, without causing
prccipilalioti, by the produc-
tion of a lemon-yellow pre-
cipitate on the addition of
Rmmoniated solution of ar-
gentic nitrate.
Ammonium snlis mny be
detected by the fxlor of ain-
tnonia, and by while fumes
from a glass rod moistoneil
with acetic acid, and held
over the oriKce of the test-tnbe, when about 1 gram of the bia-
inuthoua carbonate is heated with 10 cubic ceatirneters of a strong
solution of jMitassium or sodium hydrate,
Arsenic, Antimonjf, and Tin. — The alkaline solution obtained in
the preceding test, after thorough boiling, is diluted with water
to the measure of about 50 cubic centimeters, filtered, the filtrate
supersaturated with hydrochloric acid, and subse-
quently saturated with hydrogen sulphide; an ensu-
ing yellow or orange -colored precipitate would indi-
cate the above-mentioned impurities.
Arsenic will also be indicated, as a preliminary test,
by the development of the characteristic garlic-like
odor, when a little of the bismuthoiis sail ia heated
upon charctml, before the blow-pipe (Fig. 100).
For the confirmation or more exact determination
of the presence or absence of arsenic, one of the follow-
ioji testa should be applied :
I. About 1 gram of the bismnthous aalt is boiled for
some lime with 10 cubic centimeters of a strong solu-
tion of ]K)tassiuni hydrate, which is free from chloride ;
after cooling, the clear alkaline solution is decanted
into a test-tub^, which shoiiM be filled to not more
than one-foiirth of its capacitj', and containing about
0.5 gram of aluminium wire, cut in small pieces, or a
little bright iron wire and a few fragments of metallic
einc; a cap of bibulous paper, moistened with a drop
of a solution of argentic nitrate, is then placed over
the mouth of the tube (Fig. 101), and the liquid gently
warmed, when, if arsenic ia present, hydrogen arsenide
will be gradually de.velojjcd, and produce a black stain
up<>n the paper,
II, Three parts of the bismuthous salt are boiled for ten min-
tites with a solution of 3 parts of crystallized sodium carbonate
(free from chloride) in 30 parts of water, the solution filtered, the
filtrate evaporated to dryness, and the residue strongly heated;
Sib HASUAL OF CIIEUICAL AKALTSIS.
afier cooling, 2 parts of concentrated sulphuric acid are (^
ually added to -the Ttised residue, and, aTter first cautiously
heating, the temperature is gradually increased until a fused
mass results, from which, by continued heating, yellow vapora
cease to be evolved. The fused residue thus obtained is then <Jia-
«ulved in a small amount of water, and may be tested for arsenic,
either in Marsh's apparatus, as desuribe<l on page 33, or accord-
ing to either of the following methods :
1. A portion of the solution is added to a solution of pnre tin-
foil or stannous chloride in concentrated hydrochloric acid, and
the mixture gently wanned; a brown turbidity of the mixture,
either at once or after a while, and a grayish-brown precipitate
after subsiding, would indicate arsenic.
2. The remaining portion of the solution is added to dilate sul-
phuric acid, contained in a test-tube, together with a few frag-
ments of pure metallic zinc or magnesium, not allowing the tube
to be filled to more than one-fourth of its capacity; a can of bibu-
lous paper, moirtened with a drop of a solution of argentic nitrate,
having been placed over the mouth of the tul>e (Fig, 101), the
mixture is allowed to repose for a short time, when, if arsenic is
present, hydrogen arsenide will be developed, and produce a block
staiB upon the paper.
BiaMT7THI SUBNITRAS.
BISMUTCM SCBNITRICUM. BI^MlTLSt ALBUM.
BuinUrali or Oxg-nitraU of Biimath. Siuit BiimutAo-ut HitraU.
Oer. BbsIhIich WiiaiiitnitTat ; Fr. Snvs-azolate At bismuth ; Sp. Subnltnto
Ae bismulo.
BiO(NO,).H,0 - Bi(OH),NO,; 306.
A heavy, white powder, which, according to its precipitation
from hot or cold solutions, is either indistinutly crystalline, or ia
the form of microscopically minute crystalline scales; it reddens
moistooed blue lilmus-papcr, and becomes Wauk in contact with
hydrogen sulphide, but is not chnngeil by exposure to light, except
when containing certain inipurities, as silver salts, organic mat-
ters, etc. At 100° C. (212'^ F.) it is converted into the compound
BiO(NO,),(OH),. When heated in a dry test-tube, it first emiU
moisture, and afterward reddish -yellow acid vniMirs, leaving a
yellow residue, which, upon more strongly heating, melts to a
reddish-brown ma.ss, but, upon cooling, again aasumea a yellow
color. This residue is readily soluble in warm hydrochloric acid,
forming a solution which, when poured into a quantity of water,
produces a white precipitate, but, when mixed with strong aloo-
liol, furnishe.i a j>erfectlv clear mixture, Basic bismuthous nitrate,
when dried at 120^ C' {248" F.), loses from 3 to 5 per cent, of
BI6MUTHUM. 277
water, and, when dried at this temperature, yields upon ignition
from 79 to 82 per cent, of oxide, Bi,0, ; the variation being
attributable to a lack of uniformity in the composition of the salt,
as, according to the deviations in temperature, and proportions
and strength of the solutions employed for its precipitation, a
preparation varying in its chemical composition, as also in its
physical properties, is obtained.
When heated with exsiccated sodium carbonate, on charcoal,
before the blow-pipe, brittle globules of bismuth are obtained, and
the charcoal becomes covered with a slight incrustation, which is
of an orange color when hot, and yellow when cold. When mixed
with a little potassium iodide and sulphur, and heated on char-
coal, before the blow- pipe, a bright scarlet-red incrustation of
bismuthous iodide is produced upon the coal.
Basic bismuthous nitrate is nearly insoluble in water ; upon con-
tinued digestion, or by prolonged washing therewith, however, it
suffers an alteration in its composition, in the latter case with the
formation of the more basic salt, BiOXO, -f BiO(OH), and is
linallv converted into the hydroxide. It is also insoluble in solu-
lions of the alkaline hydrates, but by prolonged boiling with a
concentrated solution of potassium or sodium hvdratc, traces of
bismuth are occasionally dissolved, as a probable result of the
formation of bismuthic acid, and the alkaline solution then aftbrds,
upon saturation with hydrogen sulphide, a dark coloration or
precipitate of bismuth trisulphide. Basic bismuthous nitrate is
readily soluble in nitric and hydrochloric acids, and these solu-
tions, when poured into a large amount of water, form white pre-
cipitates of basic bismuthous salts.
Examination :
Carbonates and iiisolahle admixtures are detected, the former bv
effervescence in the cold, the latter by remaining undissolveil,
when a portion of the salt is warmed with about ten times its
weight of a mixture consisting of equal parts of concentrated
nitric acid and water.
The examination for other admixtures or impurities is the same
as described under bismuthous carbonate, on pages 274-275.
BISMUTHI VALERIANAS.
BI8MUTUM VALERIANICUM.
Bcuiic Valerianate of BUmuth. Ba»ie BUmutlioun Valerianate.
Ger. BasischeB Wismutvalerianat ; Fr. Valerianate de bismuth ; Sp. Valeria-
nato de bismuto.
A relatively heavy, white, amorphous powder, or, when con-
taminated with nitrate, of an indistinctly crystalline appearance,
278 MANVAL OF CHEMICAL ANALYSIS.
and possessing the odfir of valerianic acid. When the salt is
strongly heated in a dry teat-iube, colorless, acid vapors are
evolved, possessing the odor of valerianic acid, and whiuh con-
dense in the upper part of the tube to oil-like drops, while a dark
grayish colored residue, consisting of a mixture of bismuthous
oxide with metallic bismuth, remains behind. This residue is in-
completely dissolved by hydrochloric acid, but readily upon the
subsequent addition of a few drops of nitric acid, and gently warm-
ing; the acid solution thus obtained is abundantly precipitated
by the addition of a large amouotof water, but forms with strong
alcohol a perfectly clear mixture.
When heated with exsiccated sodium carbonate, or with a mi.x-
tnre of potassium iodide and sulphur, upon charcoal, before the
blow-pipe, bismiithoua valerianate affords the same reactions &s
bismuthons carbonate and niirale (pages 273, 277). In contact
with hydrogen sulphide it becomes blackened (distinction from
zinc valerianate),
Bismuthous valerianate is insoluble in water and alcohol, but
soluble in hydrochloric and nitric acids, separating an oily layer
of valerianic acid, and forming solutions which produce white
precipitates with a (juantily of water,
Bismuthous valeriauate is not a well-defined salt, and, in conse-
quence of the facility with which it is decomposed, is of incon-
stant and variable composition. One part of the salt, when repeat-
edly moistened with nitric acid in a small tared porcelain crucible,
and completely incinerated at a red heat, yields 0.68 to 0.75 (68
to 75 per ceut.) part of bismuthous oxide, Bi,0, ; thus corre-
sponding approximately to a salt of the molecular composition
(BiOiO,Il,Oj. wliich, upon ignition, should yield 71.o8 per cent,
of o.\ido.
Examination :
The solution of bismuthous valerianate in acids, after dilution
with water to an extent insuffifient to cause the precipitation of
the salt, should I>e passed through a moist double filter until a
perfectly clear solution is obtained, in order to ertect as completely
as possible the separation of the valerianic acid before the appli-
cation of the several tests,
Biamuihoug nitrate or carbonates may be detected by dissolving
a portion of the valerianate in cold concentrated hydroohlorio
acid ; effervescence indicates carbonates, and, in this case, the solu-
tion of the salt diluted with a small amount of water, insufficient
to cause its precipitation, is completely precipitated with hvdro*
gen sulphide; the solution is then filtered, warmed in oraer to
expel the excess of hydrogen sulphide, and the filtrate slightly
Bupersatu rated with sodium carbonate; a while precipitate wonM
indicate salts of cakirim, mwjnesinin, or zinc ; they may be dia-
oriminated by the same method as described on page 274.
Another part of the solution uf the valerianate in hydrooMoric
BROHUM. 279
acid is diluted with about four times its volume of water, and is
faintly tinted with one drop of solution of indigo, and then gently
warmed ; if decoloration takes place, nitrate is indicated. The
presence of nitrate may be also determined by dissolving a little
of the valerianate in cold concentrated sulphuric acid, and adding
to the liquid, in a test tube, a concentrated solution of ferrous sul-
phate, so as to form two distinct layers (Fig. 102); a brownish or
Fig. 102.
violet coloration at the line of contact of the two liquids will
indicate contamination with nitrate.
• The examination of bismuthous valerianate, i. e., of its solutions
in nitric or hydrochloric acid, for chlorides and sulphates^ for cal-
cium phosphate and salts of calcium^ mar/nesiiim, and ziric^ and for
metallic impurities, is performed in the same way as with the
corresponding solutions of bismuthous carbonate, described on
pages 274-276.
BROIffUM.
BROMINIUM.
Bromins,
Ger. Brom ; Fr. Brorae ; 8p. Bromo.
Br; 79.8.
A heavy, dark brownish-red, very volatile liquid, of an intense
and suffocating odor, somewhat resembling that of chlorine; its
spec. grav. is 2.99 at 15^ C. (59° F.).
I
280 Manual op ciibmioal analysib.
Bromine solidifies at —24.5=' C. {—12.1° F.), forming
brown, brittle, crystalline mass, with a semi- metallic lustre, Borae-
wlial resembling that of iodine, which at —12° C. ( -t-lO-i" F.)
still retains its solid condition ; when containing water it solidifies
at — 7^ C ( + 19.4° F.), It is liquid and volatile at ordinary tem-
peratures, and boils at 63^ C. (145.4" F.), forming yellowish-red
vapora of the spec. grav. 5.54 (compared with air), which strongly
irritate the organs of respiration, and impart a green color to ihe
flame.
Bromine is soluble in 33 parts of water at 15° C. (59^ F.), yield-
ing an orange-yellow solution, which has the odor of bromine,
bleaches vegetable colorij and solution of indigo, and imparts an
orange-yellow color to mucilage of starch ; when the solution is
exposed to a temperature near the freezing-point, it forma red
octahedral crystals of bromine hydrate, Br, + 10II,O, which at
15^ C. (59° F^.) are again res()lved into bromine and water. The
aqueous solution of bromine, on exposure to sunlight, gradually
undergoes decomposition with the formation of hydrobromic acid,
and the evolution of oxygen; il is deprived of its bromine and of
its color when agitated with other, chloroform, or oartwn bisul-
phide; these solutions, however, are themselves decolorized when
agitated with a solution of potassium hvdrat*; but either of them,
with the exception of carbon bisulphide, will form a new solution
of the bromine, and consequently regain the color, upon the addi-
tion of an excess of any mineral acid.
Bromine is freely soluble in alcohol and ether with a reddish-
brown color, and in chloroform, benzol, and carbon bisulphide,
forming solutions of a yellowish-red color; it is also soluble in
solutions of the alkaline hydrates, with the formation of bromide
and broinate of the alkali, and, with an excess of alkali, yielding
solutions which are colorless, or possess but a slight yellowisE
tinge:
3Br, -1- 6K0H - 5KBr + KBrO, + 3H,0.
In its chemical relations, bromine closely resembles chlorine,
having a powerful affinity for hydrogen, though not quite so
strong, and hence it acts with energy on many organic com-
pounds, abstracting hydrogen with equivalent substitution.
Examination :
Wdler may be delected by the following method, which also
iidnitls of its quantitative estimation; To a weighed amount of
the bromine, contained in a glass-stoppered bottle, about ten times
its weight of water is added, and subsequently an accurately
weighed amount of metallic mercury, equal to about twice the
weight of bromine employed. The combined liquids are then
shaken uutil complete decoloration ensues; thereupon the insoluble
mixture of mercurous bromide and mercury is separated by filtra-
tion, dried at 100= C. (212^ F.), and weighed. The difference
BROMUM. 281
between the combined weight of the amount of bromine and
mercury employed and the weight of the obtained dried mix-
ture, will indicate the presence, and represent the amount of
contained water in the bromine.
Chlorine may be detected by adding to 3 grams of the bromine
about ten times its weight of water, and subsequently water of
ammonia, in small portions, until a perfectly colorless liquid is
obtained. The liquid is then digested with an excess of barium
carbonate, the solution filtered, evaporated to dryness, and the
residue gently ignited. The ignited residue, which will contain
all the bromine, together with any chlorine which may be present,
in the form of barium bromide, or chloride, is then treated with
absolute alcohol, when it should become entirely dissolved, or
leave but a slight residue. The amount of insoluble residue, consist-
ing of barium chloride, will bear a direct proportion to the amount
of chlorine contained in the bromine, which, in the commercial
product, is usually present to the extent of from 1 to 2 per cent.
Iodine may be tested for by dissolving a portion of the bromine
in forty times its weight of water, and the solution thus obtained,
with the exception of a small reserved portion, is agitated with
reduced iron or iron filings until a nearly colorless liquid is
obtained, and the bromine is completely converted into ferrous
bromide. The liquid is then filtered into a test-tube, a little
mucilage of starch added, and subsequently a few drops of the
reserved aqueous bromine solution carefully poured upon the sur-
face ; if iodine be present, a blue zone will appear at the line of
contact of the two liquids. The presence of iodine may also be
detected by the addition of an aqueous solution of the bromine
to a solution of ammonium sulphide until no further separation of
sulphur is produced, the liquid then evaporated upon the water-
bath to dryness, the residue dissolved in water, filtered, a few
drops of a dilute solution of ferric chloride added, and the mix-
ture shaken with chloroform ; if iodine be present, the chloroform
will assume a violet color.
Bromoform will be recognized by the development of its charac-
teristic odor, when a little of the bromine is added to a solution of
potassium iodide, and the liberated iodine subsequently dissolved
by means of a solution of sodium hyposulphite. When present to
any considerable extent, it mav be separated by fractional distilla-
tion ; its boiling-point being at 150 to 152° C. (302 to 305.6° F.).
Cyanogen or its compounds may be detected by adding about
10 grams of the bromine to be tested, very gradually, and with
constant stirring, to an equal weight of iron filings, previously
mixed with 4 or 5 times their weight of water. The liquid, while
still warm from the reaction, is filtered into a flask, which is after-
ward partially closed, and allowed to repose for one or two days ;
if cyanogen or its compounds are present, a precipitate of Prussian
blue will be gradually deposited.
282
NUAL OF CHEMICAL ,
EstimatioB :
Tho quantitative estimation of free bromine, with a view to the
dettTiiiinatioii of the amount of impurities present, may be most
conveniently accomplished by the following volu-
" "" metric method: About 0.3 gram of the bromine
is accurately weighed in a small glass bulb (Fig.
103), which ia afterwards opened under the sur-
face of a solution of about 1 gram of potaxainm
iodide in 10 cubic centimeters of water, and the
liberated iotline estimated by means of a standard
solution of sodium hyposulphite, page Ui. From
the amount of liberated iodine, the corresponding
amount of bromine may be calculated by simple
equivalent proportion; one atom of iodine (126.6)
corresponding to one atom of bromine (79,8).
Should the bromine, however, contain chlorine as
jg^ an impurity, the latter will likewise liberate iodine
^■A from the potassium iodide, and thus preclude the
^(^ direct calculation of the bromine. In the latter
case, the calculation may be based upon the fol-
lowing consideration : If ^ — the amount of libe-
rated iodine, as determined by titration with a solution of sodium
hypo.sulphile, and B ™ the weight of employed bromine ; then the
amount of chlorine, X, which is contained in the bromine under
examination, may be ascertained in accordance with the follow-
ing formula:
A — 1.5875 B
2.0312
and the amount of pure bromine is conRequently B — X,
X-
BRUCINA.
URUCINUM.
Ger. Bniclni Fr. Bnicine ; Sp. Brucina.
C„H^N,0, -f- 4H,0 i 466. '
Transparent, colorless, four-sided prisms, aggregations of stel-
late needles, or a crystalline powder, with a pearly lustre, and
possessing a strongly bitter taste. Brucine contains 4 molecules
(15,45 per cent.) of water of crystallization, and effloresces upon
exposure to the air ; it melts at 130^ C. (266" F.), gradually losing
its water of crystallization, and, upon further heating, may be
partially sublimed without deoompo.sition ; when strongly heated
upon platinum-foil, it is decomposed with the evolution of uiflam-
malile vapors, which burn with a bright sooty flame, and is finally
completely dissipated.
Brucine is soluble in 320 parta of cold, and in 150 parts of
boiling, water, very freely soluble in alcohol, amylic alcohol,
chloroform, and benzol, but is sparingly soluble in ether and
petroleum benzin. It neutralizes the acids, forming crystallizable
salts, which possess a bitter taste, and are readily soluble iu water
and alcohol, but insoluble in ether.
Brucine dissolves in moderately concentrated nitric acid with nu
intense blood-red color, which, however, soon changes to yellow-
ish-red, and finally, upon warming, to yellow. If the acid solution
be subeequeutly slightly warmed with a little water, again allowed
to cool, and a few drops of solution of stannous chloride or am-
moiiinm sulphide added, the mixlure assumes a beautiful violet
color. The reaction is best obtained by the employment of but
little nitric acid, and is not inSueiiced by the presence of strych-
nine. If a solution of mercurous nitrate be slightly warmed in a
sliallow porcelain capsule on the water-bath, and an aqueous solu-
tien of brucine added, a finr red coloration is gradually produced at
theedgesoftlie liquid, which, by the slow evaporation of the liquid
to dryness, remains permanent. Brucine dissolves in concentrated
sulphuric acid with a slight rose-red coloration, and the solution
assumes, upon the addition of potassium bichromate, a transient
reddish-brown color. If the brucine contains strychnine, traces
of which are frequently present in the commercial alkaloid, its
solution in sulphuric acid will aft'ord, upon the addition of potas-
sium bichromate, a rapidly fading blue-violel coloration. With
concentrated sulphuric acid, which contains a trace of nitric acid,
brucine aflbrds an intensely red solution.
Chlorinewat^r colors an aqueous solution of a brucine salt first
violet and then red, and, upon the subsequent addition of ammo-
nia-water, a yellowisli-brown color is produced. Aqueous solu-
tions of brucine salts arc precipitated by the alkaline hydrates and
carbonates, as also by most of the commonly employed alkaloidal
reagents, and yield crystalline precipitates with potassium chro-
mate, sulphcxsyanide, and ferrioyanide. By the action of oxidising
agents, brucine aftbrds several interesting products of decompo-
sition. Thus upon heating with dilute sulphuric acid and man-
ganese dioxide, raethylic alcohol and formic acid are produced,
with the development of oarbonic acid gas. By treatment with
concentrated nitrto acid, it assumes, as previously stated, an
intense red color, and is resolved into water, nitric oxide, oxalic
Bcid, methyl nitrite, and a crystal lizable base, cacoteltne.
C„H^N,0.+5I1N0,=2 n,0+2 NO+C,n,0,+C E.N 0,-fC^H„Np,.
Bruraae, Csooleliue.
For the separation of brucine from other alkaloids, or when
associated with complex organic mixtures, see page 108.
Manual up chemical .
CABMII lODIDUU.
CADMIUM lUDATUM.
Iodide of Cadmium. Gadmiiitn Iodide.
GCT JodciHimiiirn ; Fr. lodure de cadmiom ; Sp. Iijduro dc c&dniEo.
C<ll,i 365.
Colorless, flat, micaceous crystals, or hexagonal tabJes, of a
pearlv lustre, permaoent in the air, and having a s|)eaific gravity
of 4.576.
When heated to aboui 316° C. (600.8° F.), the salt melts, form-
ing an amber-colored fluid, and, at a dull red heat, is decomposed
with the evolution of violet colored vapors of iodine.
Cadmium iodide is froelv soluble in water: 100 parts of water
dissolving, at 20° C. (68° F.), 92.6 parts, at 60° C. (HO" F.). 107.5
parts, and at 100° C. (212* F.), 133.3 parts of tiie salt; il is also
quite freely soluble in alcohol, and in a mixture of alcohol and
ether. The aqueous solution has a slightly acid reaction upou
litmus, and yields with hydrogen sulphide or ammonium sulphide
a yellow precipitate, which is almost insoluble in an excess of the
latter reagent (distinction from arsenic): with argentic nitrate it
yields a pale yellow precipitate, insoluble in ammonia-water; with
mercuric chloride a bright red precipitate; and with the alkaline
hydrates and carbonates white precipitates, of which that with
nminonift-water is soluble, the remainder insoluble in an excess of
the precipitant. If to the aqueous solution of the salt a little
chlorine water he added, drop by drop, and sub.'^equently a little
mitcilage of starch, the mixture will assume a deep blue color.
One hundred parts of cadmium iodide, when completely pre-
cipitated by argentic nitrate, vield a precipitate of argentic iodide,
which, when thoroughly washed, and dried at 100° "C. (212° F.),
should weigh 128.55 parts.
Examination:
Metallic finpuritief. — The aqueous solution of the salt, acidu-
lated with hydrochloric acid, is completely precipitated by hydro-
gen sulphide, the resulting precipitate collected and washed upon
a filter, and subsequently digested with ammonia-water, and
again filtered ; the latter filtrate, when supersaturated with hydro-
chloric acid, should afford no turbidity ; an ensuing yellow colora-
tion or precipitate will indicate the presence of arsenic. The
filtrate from the original hydrogen sulphide precipitate is then
supersaturated with ammonia- water; an ensuing white precipi-
tate would indicate zinc, a black one, inm.
Chlorides may be detected by cpmplelely precipitating a small
portion of the aqueous solution of the salt with argentic nitrate,
collecting and washing the resulting precipitate upon a filter, and
CADMIUM. 285
subsequently digesting it with ammonia-water, and filtering; the
ammoniacal filtrate is then supersaturated with nitric acid, when
an ensuing w^hite curdy precipitate will indicate the presence of
chloride.
CADMII 8X7LPHA8.
CADMIUM 8ULFURICUM.
Sulphate of Cctdmium. Cadmium Sulphate.
Ger. Schwefelsaures Cadmium ; Fr. Sulfate de cadmium ; Sp. Qulfatodecadmio.
3CdSO,.8H,0; 767.4.
Colorless, transparent, rhombic tables, having a specific gravity
of about 3., and containing, for 3 molecules of the salt, 8 mole-
cules (18.8 per cent.) of water of crystallization. They effloresce
slightly by exposure to the air. lose 5 molecules of water upon
drying at 100° C. (212° F.), and the remaining 3 molecules at a
higher temperature.
Cadium sulphate is soluble in twice its weight of water at 17° C.
(62.6° F.), but insoluble in alcohol. The solution has an acid re-
action upon litmus, an astringent, acidulous, and slightly austere
taste, and, when diluted with six times its volume of water, may
be mixed with considerable amounts of alcohol without the sepa-
ration of the salt, which finally takes place in the form of thick
liquid drops.
The aqueous solution yields upon the addition of potassium or
80<lium hydrate, or ammonia- water, a white precipitate of cad-
mium hydroxide, which is insoluble in an excess of the first-
named reagents, but soluble in an excess of ammonia-water; with
alkaline carbonates it yields a white precipitate of cadmium
carbonate, insoluble in an excess of the precipitant; and with
hydrogen sulphide, a yellow precipitate of cadmium sulphide,
which is soluble in moderately concentrated, warm sulpnuric,
hydrochloric and nitric acids, and to a slight extent in a solution
of ammonium sulphide, but is insoluble in diluted acids and
ammonia-water (distinction, in the latter instance, from arsenious
sulphide).
Examination:
Arsenic may be detected by completely precipitating an acidu-
lated solution of the salt with hydrogen sulphide, digesting the
resulting precipitate with ammonia- water, filtering, and subse-
quently supersaturating the clear liquid with hydrochloric acid;
the separation of a yellow precipitate will reveal the presence of
arsenic. The acidulated solution of the salt, when completely
precipitated by hydrogen sulphide, should yield a filtrate, which,
upon evaporation to dryness, should leave no residue ; if a residue
286 MASl'AL OF CUEMICAL ANALYSIS.
remains, admixtures of other salts are indicated. In the latter
case, the residue should be dissolved in dilute hydrochloric acid,
and examined for metallic, earthy, and alkaliue oxides by the
sy.ilematic method of analysis as described on [tages 56 to til.
EBtimatioa:
The quantitative estimation of cadmium may he readily accom-
plished by precipitating the carbonate from a boiling solution of
a weighed quantity of the sail, by means of .-sodium carbonate;
the precipitate is tnoroughly washed, dried, and, by ignition at a
red neat, converted into cadmium oxide, CdO, from the weight of
which the corresponding amount of anhydrous or of crystallized
cadmium sulphate may be calculated: 100 parts of cadmium
oxide, CdO, corresponding to 1(12.69 parts of anhvdrous sulphate,
CdSO,. or 200.S1 parts of crystallized sulphate, 3CdS0^.8H,O.
Ii may also be estimated by precipitation by hydrogen sul-
phide froman acidulated solution of its salt as ca*dmium sulphide,
CdS, which, after washing, is dried at 100° C. (212^ K.), and
weighed. One hundred parts of cadmium sulphide correspond to
144.56 parts of anhydrous sulphate, CdSO^ or 178 parts of crys-
taUized sulphate, 3CdSO,.8n,0.
CAPPEiNA.
C O F F E I N U -M.
C'ifffint. Caffeia. Theina. Quaraniiie. Mtlhyllhtabrom(at.
Gcr. Cnffcin ; Fr. Cnfflnp ; Sp. CnMoh.
C,H,.N,0, + H,0 - C,H,(CH,)N.O, -|- H,0 ; 212.
Colorless, slender, and tlexible, silky needles, containing one
molecule (8.49 per cent.) of water of crystallization, which is lost
by drying at 100" C. (212° F.). The crystals are odorless, neu-
tral in their action upon litmus, and poSMe.-sa slightly bitter taste.
They melt at 234 to 235° C. (453.2 to 455° F.), althougli begin-
ning to sublime at 180° C. (^6b^' F.), aud boil at 384^ 0. (723.2°
F.); when slowly heated upon platinum foil, they are completely
volatilized, without carbonizing.
Cafteine, when previously deprived of its water of crystalltJM-
tion, is soluble tii 76 parts of water at 15° C. (59" F.), in 2 parts at
70* C. (158° F.), in 8 parts of chloroform, in 50 parts of ordinary
alcohol, and in 520 parts of absolute alcohol, aud is still lens solubfe
in ether and carbon bisulphide. The aqueous solution is neutral
in its action upon litmu.s, and possesses a slightly bitter taste; it
is abundantly precipitated by tannic acid, the precipitate being
readily re-dissolved upon warming, or upon the addition of an
e.fcesa of the reagent, but is not precipitated by pierie acid, nor
by a dilute solution of potassio- mercuric iodide (distinction from
most other alkaloids); it also remains unnhered, and does not as-
sume a purple color, when it is exposed lo the air, after the addition
of a little ammonia-water (distinction from phlorizin).
Caffeine enters into combination with the stronger acids, with-
out neutralizing them, with the formation of salts having an acid
reaction, and which are readily decomposed; it also forms crys-
tallizable compounds with some metallic salts. From its solution
in the weaker acids, it crystallizes, upon CTaporation, unchanged.
With concentrated sulphuric and nitric acid«, caffeine suffers no
change of color in the cold (additional distinction from many alka-
loids, and from aalicin, which, with the former acid, produces a
bright red coloration. When caffeine is added to chlorine-water,
iu a small porcelain capsule, and evaporated to dryness, a yellow-
ish-red residue is obtained, which, upon the addition of a little
ammonia-water, aseumes a beautiful purplish-red color. The
same reaction may be obtained by the employment of a little
nitric acid, inalead of clilorine-walcr, care being taken to avoid
an excess of the acid; with the application of bromine- water,
instead of chlorine, the coloration, upon the addition of ammonia,
is more of a violet hue.
When boiled with an alcoholic solution of potassium hydrate,
or with an aqueous solution of barium hvdrate, caffeine is re-
solved, by the absorption of water and the elimination of carbonic
acid gas, into an uncrystallizable base, caffeidini:, C,H,jN,0, which
is very readily soluble in water and alcohol, and whose sulphate
crystallizes in long, colorless needles:
C.Ii.AO. + H,0 - C,H„N,0 + CO,.
The decomposition of caffeine by barium hydrate is, however,
not confined to the production of cafteidine, but methylainine,
formic acid, and ammonia are simultaneously formed, and, by tLe
long-continued action of the reagent, the caffeiJine is itself decom-
posed into the above products and sarkosine, C,H,NO„ with the
erolntion of carbonic acid gas.
CALCII BROMIDUM.
CALCIUM BROMATDM.
Bromide of CaUium. Oaleitm Bromidf.
Ger. BromcalchiBi ; Fr. BrOmure de cntcitiiD ; !^p. Bnimuro Ae cal.
CaBr,; 199.6.
A white, granular salt, rapidly abKorbing moisture on exposure
to the air, and deliquescing to a syrupy liquid. Its specific grav-
ily ie 3.32. Wlieo heated to 680^ C. (12'i6° F.) the salt under-
goes igneous fuaiun, and, at a higher temperature, it is decomposed
with the liberation of bromine.
Calcium bromide is soluble in 0,7 part of water and in 1 part of
alci>hol at 15® C. (59° F.), and very freely soluble in boiling water
and boiling alcohol. Its aqueous solution is neutral in its action
upon litmus, and possesses a pungent, saline, and bitter taste; it
yields a white precipitate with ammonium oxalate, soluble in
liydrochloric, but insoluble in acetic acid; and a white precipitate
with argentic nitrate, which is sparingly soluble io ammonia-
water. If a little chloroform or carbon bisulphide be added to a
solution of the salt, and subsequently a little chlorine- water, drop
by drop, and the whole agitated, the chloroform or carbon bisul-
phide will acquire a yellow or yellowish brown color.
One gram of the dry salt, when completely precipitated by
argentic nitrate, yields a precipitate of argentic bromide which,
when washed, anfl dried at 100^ C. (212° F.), should weigh 1.878
grams.
Examinatioii :
Jiromote may he detected by a yellow coloration when diluted
sulphnrtc acid is dropped upon the salt ; or by adding to an aque-
ous solution of the salt a few drops of diluted sulphuric acid, and
auhsequently a little chloroform or carlxm bisulphide, and agita-
ting the mixture ; if bromate be present, the chloroform or carbon
bisulphide will acquire a yellow or yellowish brown color.
lodidf. may be recognized in a solution of one part of the salt
in about ten parts of water by the addition of a little mucilage of
starch, and subsequently pouring a few drops of chlorine- water
upon the surface of the liquid; a blue coloration at the Hue of
contact of the two liquids will reyeal the presence of iodide.
Chloride may be delected by completely precipitating a small
portion of an aqueous solution of the salt with argentic nitrate,
collecting the resulting precipitate upon a filler, washing it tho-
roughly with water, and subsequently digesting it with a concen-
trated solution of ammonium carbonate; the mixture is then
filtered, and the filtrate supersaturated with nitric acid, when not
more than ^ faint tnrbidity.insufficient to form a precipitate, should
be produced ; a white, curdy precipitate would reveal the presence
of more than traces of chloride.
Sul/ihnle may be detected in a solution of 1 part of the sail in
about 20 parts of water by an ensuing white precipitate on the
addition of a few drops of solution of barium chloride.
Ma'jnrBium aalta may be recognized by first adding to an aque-
ous solution of the salt a little solution of ammonium chloride,
and aAerward solution of ammonium carbonate and ammonia-
water until a precipitate ceases to be produced, and gently warm-
ing; the mixture is then filtered, and the filtrate tested with
sodium phosphate, when an ensuing white, crystalline precipitate
will reveal the presence of magnesium salt.
CALCIUM. 289
CALCII CARBONA8 PRiBCIPITATUS.
CALCIUM CARBONICUM PRECIPITATUM. CALCARIA
CARBONICA PRECIPITATA.
Precipitated Carbonate of Calcium. Precipitated Calcium Carbonate.
Ger. Kolilensaurer Kalk ; Fr. Carbonate de chaux ; 8p. Carbonato de cal.
CaCO,; 100.
A white, light powder, without odor or taste, and permanent
in the air. When obtained by precipitation from hot solution.s,
it is seen, when observed under the microscope, to consist ot'
minute rhombic prisms, or, when precipitated from cold solutions,
of minute rhombohedral crystals, although the crystalline form is
frequently influenced by other substances which may be present
in the solution. It displays a feebly alkaline reaction in contact
with carefully prepared litmus; when exposed to a red heat, par-
ticularly when a current of air is passed over the surface, or, when
heated upon charcoal before the blow-pipe, it loses carbonic acid
gas, and is converted into calcium oxide, which possesses a strongly
alkaline reaction.
Calcium carbonate is almost insoluble in water, 1000 parts of
water, either cold or hot, dissolving but about 0.018 part, and is
still less soluble in the presence of free ammonia or ammonium
carbonate; but is more freely soluble in the presence of ammo-
nium chloride or nitrate, with which, by mutual decomposition, a
more readily soluble calcium salt is formed. It is also more freely
soluble in water saturated with carbonic acid gas than in pure
water; this solution reddens litmus, but changes the yellow color
of turmeric-paper to brown : by boiling or exposure to the air,
the carbonic acid is evolved, and the calcium carbonate partially
deposited; the liquid still retaining, in 1000 parts, 0.034 part of
calcium carbonate in solution, and this solution does not render
lime-water turbid. It is readily soluble, with eft'ervescence, in
dilute hydrochloric, nitric, and acetic acids. The solution in
acetic acid is precipitated by oxalic acid, but not by a solution of
calcium sulphate (distinction from barium and strontium car-
bonates), nor by ammonia-water (evidence of the absence of
aluminium and iron salts, and of phosphates), nor by potassium
hydrate (distinction from magnesium carbonate). The solution
snould also afford no coloration or precipitate with hydrogen sul-
phide, either when containing an excess of acid, or upon subse-
quent supersatu ration with ammonia- water (free from carbonate).
Examination :
If the calcium carbonate be agitated with a little water, and the
mixture filtered, the filtrate should be perfectly neutral in its
action upon litmus, and, with the exception of traces of dissolved
carbonate, should leave no residue upon evaporation. Upon igni-
tion, at a red heat, it should aflFora a perfectly white residue,
19
290 MANUAL OP CHEMICAL ANALYSIS.
possessing a strongly alkaline reaction, without the development
of any empyreumatic odor.
An insufficient washing in the roanufacture, or a fraudulent or
accidental admixture of calcium stilphate, may be detected by
agitating some of the carbonate with water, and by testing the
filtrate, acidulated with one or two drops of nitric acid, in separate
portions, with argentic nitrate for chloride, and with barium
nitrate for sulphate,
Mai/nesi'um carftmiafe may be recognized, in addition to the
above-mentioned test, by adding to a neutral solution of the salt
in acetic acid, first solution of ammonium chloride and then am-
monium carbonate and ammonia-water until a precipitate ceases
to })e produced, and gently warming ; the mixture is then filtered,
and the filtrate tested with sodium phosphate, when an ensuing
white, crystalline precipitate will prove the presence of magnesium
salt.
The crude vareties of calcium carbonate — chalk, prepared
oyster-shells, and others derived from animal organisms — contain
more or less of other bases (magnesium, iron, potassium, sodium,
etc.) and acids (phosphoric, silicic, and sulphuric), and always, also,
traces of organic substances ; they do not afford a complete solu-
tion with dilute acetic or hydrochloric acid, and, althougn in every
instance the acid solution should remain unaffected by hydrogen
sulphide, yet upon subsequent supersatu ration with ammonia-
water a white or greenish turbidity is usualiy produced, depend-
ent upon the presence of traces of phosphates. The estimation
of the amount of carbonic acid contained in calcium carbonate
may be accomplished by the method described for alkaline car-
bonates, on page 86.
CALCII CHLORIDUM.
CALCITJM CHLORATUM.
Chloride of Calcium. Calci\
Ger. Clilorcfllcium ; Fr. Cblororo de cslchim ; Sp. Cblornrci Ac cnlcln.
GaOl,: 110.8.
A white, granular salt, or, as prepared by fusion, colorless, trans-
lucent, and friable masses; it may also lie obtained by crystalli-
zation from its saturated solution in the form of large hexagonal
prisms, having the composition CaCl, + fiH,0. The crystals melt
at 29° C. (84.2° Y.) in their water of crystallization, and deli-
quesce rapidly by exposure to the air, forming a thick syrupy
liquid. When heated to 200° C, (392" F.), they lose 4 molecules
of water, leaving a white, porous, hygroscopic mass, and, upon
more strongly heating, the anhydrous salt ia obtained ; the latter
CALCIUM. 291
melta at a red heat, anil, upon cooling, solidifies to a crystalline maas
of tlie specific gravity 2.205, which, in contact with a Hmall amount
of water, produoea a considerable elevation of temperature.
Calcium chloride is soluble in 1.5 parts of water and in 8 parta
of alcohol at 15° C, (59° F.), very freely soluble in boiling water,
and soluble in 1.5 parts of boiling alcohol ; with alcohol it unites
to form a cryatalliaable compound, having the composition
CaCl, + 40,11,0, which is decomposed by water with the separa-
tion of the alcohol ; but is insoluble in ether. The aqueous aolu-
tioii of the salt possesses a sharp saline taste, and is neutral in Jls
action upon litmus, unless the salt, by exposure to the heat of
fusion, has undergone partial decomposition, with the loss of hy-
drochloric acid, and the formation of a little calcium oxide, when
it will have an alkaline reaction ; it yields white precipitates with
the alkaline carbonates and phosphates, which are readily soluble
in acetic acid, and, if the solution be not too dilute, a white crya-
talline precipitate with sulphuric acid, which is soluble in a large
amount of water. The solution of thesalt, even when very dilute,
is likewise precipitated by oxalic acid and Ijy argentic niirate;
both precipitates being insoluble in acetic add, and that with the
latter reagent also insoluble in nitric acid, but readily soluble in
ammonia- water.
Anhydrous calcium chloride absorbs dry ammonia gas with great
avidity, forming therewith a voluminous powder, having the com-
poeitiou CaCl, + 8NHj; this ia decomposed by exposure to the
air, in contact with water, or on heating, with the loss of ammo-
nia, and takes fire when thrown into chlorine gas.
If a concentrated solution of calcium chloride is boiled with
slaked lime, and the solution filtered while hot, a basic salt sepa-
rates out on cooling, in long, white, needle-shaped crystals, having
the composition ClCa-O-Ca(OlI) + 7H,0.
Solutions of calcium chloride of various degrees of concentra-
tion are employed as hatha for constant temperatures above 100°
C. {2ia° F.), and the anhydrous salt, in consequence of its strong
affinity for water, is largely employed as a desiccating agent, for
drying gases, and for the removal of water from organic liquids.
The crystallized salt, when dissolved in water, produces a consider-
able diminution of temperature, and, when mixed with snow, in
the proportion of 1.3 parts to 1 part of the latter, the temperature
sinks to — 4s- C, (—54.-1^ F.).
Examination ;
■ Calciujn sulphate may be delected by the incomjdete solubility
of the salt in alcohol, and may also be recognized in the aqueous
eolation of the salt by,an ensuing white precipitate on the addition
of aolulion of barium chloride.
Aluminium sails may be recognized in the aqueous solution,
fifter the addition of a little ammonium chloride, by an ensuing
white, flocculeut precipitate on the addition of ammonia-water or
29*2 MANUAL OF CHEMICAL ANALYSIS.
amnionimn sulphide; if the precipitate be brownish or bla(
will indicate iron, which may also be recognized in the aqueotis
solution of the salt by a blue coloration or precipitate on llie
addition of a few drops of solution of potassium ferrocyanide.
ifayneaium salts may be recognized by adding to the arjueoas
solution, first a little solution of ammonium chloride, and subse-
quently ammonium carbonate and ammonia-water until a pre-
cipitate ceases to be produced, and gently warming ; the mixture
is then filtered, and the filtrate tested with sodium phosphate,
when an ensuing white, crystalline precipitate will reveal the
presence of magnesium.
CALCn BTPOFHOSFHIS.
CALCIUM HTPOPHOSPHOROfiUM. CALCIS BYPOPnOSPHIS.
Itgpophotphite of Oalfiam. Caieium Hypopho»phitc.
Ca{H,POJ,; 170.
Small, colorless, transparent, four-aided prisms, or thin, flexible
scales, or a white, crystalline powder, of a pearly lustre, perma-
nent in the air, and containing no water of crvstallization. When
strongly heated in a dry test-lube, the salt decrepitates, emitting
inflammable vapors of hydrogen phosphide, and a little water,
and leaving a residue, amounting to about 80 per cent, of its
weight; this residue, af^er cooling, appears yellowish -red, and
coDsiats of a mixture of calcium pyrophosphate and metaphofi-
fihate, together with a little red amorphous phosphorus, resulting
rom the decomposition of the hydrogen phosphide.
Calcium hypopbosphite dissolves in six parts of cold water,
and in about the same amount of boiling water, but is insoluble
in alcohol (distinction from sodium hypophospliite); the aqueous
solution has a slightly bitter taste, and, when largely diluted with
water, suffers no change upon the addition of diluted sulphuric
acid, nor with solutions of barium and calcium chlorides, nor of
plumbic acetate (distinction from soluble phosphates and phoa-
phites); it forms, however, white jirecipitates with the soluble
carbonates, with oxalic acid and oxalates, and with argentic
nitrate, which latter precipitate, in connequence of its rapid reduc-
tion to argentic phosphide and metallic silver, soim becomes
black. When an aqueous solution of the salt, acidulated with
hydrochloric acid, is added to an excess of solution of mercuric
chloride, a white jirecipitate of mercnrous chloride (calomel) ia
produced, and, on the further addition of the solution of hypo-
phosphite, metallic mercury separates.
k
CALCIUM. 293
Examination :
The salt, when triturated with water, should not develop the
alliaceous odor characteristic of hydrogen phosphide.
Calcium sulphate will be indicated by an insoluble residue when
a portion of the salt is digested with about ten times its weight
of cold water, and may also be recognized in the aqueous solution,
acidulated with nitric acid, by an ensuing white precipitate on the
addition of a few drops of solution of barium chloride.
Magnesium salts may be detected by first adding to an aqueous
solution a little solution of ammonium chloride, and afterward
solution of ammonium carbonate and ammonia-water until a pre-
cipitate ceases to be produced, and gently warming; the mixture
is then filtered, and the filtrate tested with sodium phosphate,
when an ensuing white, crystalline precipitate will reveal the
presence of magnesium.
CALCII lODIDUM.
CALCIUM lODATUM.
Iodide of Calcium, Calcium Iodide,
Ger. Jodcalcium ; Fr. lodure de calcium ; Sp. loduro de cal.
Cal,; 293.2.
A white, granular salt, or lamellar masses of a pearly lustre,
rapidly absorbing moisture on exposure to the air, and deliques-
cing to a syrupy liquid. When strongly heated, with access of
air, it becomes decomposed, with the liberation of iodine, and
leaving a residue of calcium oxide.
Calcium iodide is very freely soluble in both water and alcohol.
Its aqueous solution is neutral in its action upon litmus, and pos-
sesses a pungent, saline, and bitter taste ; it yields a white pre-
cipitate with ammonium oxalate, soluble in hydrochloric, but
insoluble in acetic acid, and a yellowish precipitate with ajrgentic
nitrate, which is nearly insoluble in ammonia-water. If a little
chloroform or carbon bisulphide be added to a solution of the salt,
and subsequently a little chlorine- water, drop by drop, and the
whole agitated, the chloroform or carbon bisulphide will acquire
a red or violet color. One gram of the dry salt, when completely
precipitated by argentic nitrate, yields a precipitate of argentic
iodide which, when washed, and dried at 100° C. (212° F.), should
weigh 1.59 grams.
iSamination :
lotlate may be detected in the aqueous solution of the salt by a
yellowish or brown coloration on the addition of a little acetic or
tartaric acid ; the solution will then also impart a blue color to
294
MANUAL OF CllBUICAL ANALYSIS.
iriiiciliigo of starch, and a rod or violet tint to a few drops of ohloro-
fi)rm OP oarbon bisulphide, when agitated therewith, if iodate be
present.
Chlorides and Bromides. — To a small portion of the salt, dis-
aolved in water, solutiou of argentic nitrate is added until a
precipitate ceases to be produced. The resulting precipitate is
collected upon a filter, washed with water, and subsequentlr
digested with a strong solution of ammonium carbonate, and fil-
tered; the filtrate is then slightly supersaturated with nitric acid,
when an ensuing turbidity, or the formation of a white, curdy
precipitate, will reveal the pre?cnoe of chloride. The residue
upon the filter is digested witn a considerable excess of ammonia-
water, filtered, and the filtrate slightly supersaturated with nitric
acid, when not more than a faint turbidity should ensue ; a white,
curdy precipitate will reveal the presence of bromide.
Sulp/iale may be delected in a solution of 1 part of the salt
in about 20 parts of water by an ensuing while precipitate on the
addition of a few drops of solution of barium cliloride.
Maijnrainm sails may be recognized by first adding to an aque-
ous solution of the salt a little solution of ammonium chloride,
and iiflerwjtrd solution of ammonium carbonate and ammonia-
water until a precipitate ceases to be produced, and geutiy warm-
ing; the mixlure ia then filtered, and the filtrate tested with
sodium pho-sphate, when an ensuing white, crystalline precipitate
will reveal the presence of magnesium.
CAI.GII PBOSFHAS PRJECIFITATUS.
CALCI8 PBOSPUAS. CALCIUM rHOSPlIOHICUM. CALCARIA
PHOSPHORICA.
Pfteipitatsd Ph/>$a\at» of OaleiuM. Teibntif Cnlrium PhoipKatt.
ifomal Oalfium Orl?uphtitph-ilt .
Oct. NeatT*l«r Phosphorsaurer Kalk ; Fr. Phosphate Ae chaus prJclptIi i
Sp. Fosbto d« cal.
Ca,(PO,),; 310.
A light, white, inodorous, and lasleleas powder, which, when dried
tX UKP 0.(212° F.), contains no water, and is perfectly amorphous.
' Jt is fusible, without decomposition, at an intense heat, and the
I powder, before or after ignition, assumes when moistened with a
flolution of argentic nitrate a straw-yellow color (distinction &om
sckI oalciom phosphate).
Neutral calcium phosphate is nearly insoluble ia water, bat
upon long boiling therewith it is decomposed with the Fomtation
of aa insoluble basic salt, Cay^PO^ -|- Ca-(POJOII, and a solabte
acid salt which dissolves ; it is more readily soluble in water sata-
nxeii with carbonic acid gas, as alsu in solutions of sodium nitrate,
CALCIUM. 295
sodium chloride, amraoniacal, and other salts, and is freely soluble
in nitric, hydrochloric, and acetic acids.
An acid calcium phosphate (Monohydrogen Calcium Ortho-
phosphate, CaHPO^ 4- 2H,0) is officinal in the German, Austrian,
and Swiss Pharmacopoeias. This salt is obtained as a crystalline
powder, consisting of microscopically small, monoclinic tables or
prisms, of an acid reaction, and containing two molecules (20.93
per cent.) of water of crystallization; when heated to from 150 to
200^ 0. (802 to 392^ F.), it loses its water of crystallization, and,
at a higher temperature, water of constitution is also eliminated,
amounting in all to 26 per cent, of its weight. When moistened
with a solution of argentic nitrate, it assumes a yellow color,
which is not the case, however, after having been strongly heated
upon platinum-foil, in consequence of its conversion into calcium
pyrophosphate: 2CaHP0^ = H,0 4- Ca,PjOy. In its relation to
solvents, the characters of acid calcium phosphate are similar to
those of the normal salt, as above described, but it is not readily
soluble in acetic acid.
Both varieties of calcium phosphate are readily and completely
soluble in warm, diluted nitric acid, without effervescence. The
solution, when heated with a few drops of a solution of ammonium
molybdate, aflFords a yellow crystalline precipitate of ammonium
phospho-molybdate (presence of phosphoric acid), and, after the
addition of an exces^s of sodium acetate, yields a copious white
precipitate on the addition of a solution of oxalic acid or ammo-
nium oxalate (presence of calcium).
Examination :
Carbonates are indicated by effervescence when a little of the
calcium phosphate is first thoroughly mixed with a little water,
and concentrated nitric acid afterwards added.
Barium and strontium salts may be detected in the dilute nitric
acid solution by a white precipitate on the addition of a solution
of calcium sulphate.
Chlorides are detected in the dilute nitric acid solution by a
white curdy precipitate on the addition of solution of argentic
nitrate, which is soluble in ammonia-water, but insoluble in nitric
acid.
Sulphates may be detected by agitating a little of the calcium
phosphate with water for a few moments, filtering, and, after
acidulating with a few drops of acetic acid, testing with solution
of barium hydrate or nitrate; a white precipitate will reveal the
presence of sulphates.
Maynesium Phosphate, — A portion of the salt is dissolved in
hydrochloric acid, an excess of sodium acetate and a little solu-
tion of ferric chloride are added, and the mixture boiled and
filtered; to the colorless filtrate a little ammonium chloride is
added, and subsequently ammonium oxalate until a precipitate
ceases to be produced ; after standing for a few hours, the mixture
MANUAL OF CHEMICAL ANALYSIS.
29tl
is tiltereci, ani] to tlie filtrate solulion of sodium \
nminonia- water in slight exwss are added, when an ensuing while
crystnlline precipitate will revea! the presence of magnesium.
Iron and metallic salts are detected by firal saturating the solu-
lion of the calcinm phosphate in dilute hydroahloric acid with
hydrogen Biilphido, and subseqnently supernatu rating the aeid
liquid with ainmonia-waler. The solution must remain jterfectly
unchanged with the firat-nsmed reagent, and the ensuing precipi-
tate upon the addition of the latter should be jierfectly white; a
black coloration would indicate iron, which would likewise be
detected in the dilute acid solution of the aa!t by a blue colora-
tion or predpilate on the addition of a few drops of solution of
potassium ferrocyanide.
CALX CBIJORATA.
CALK CHLOR[NATA. CALCARIA CHLORATA. CALCIUH
HTPOCHL0R08UM. CALCARIA HYP0CHI.0R03A.
Chlorinated Lime. liUaehing-Poaider. Oateium Hgpoehlori'U.
Oer. Clilorkalk; Fr Clilorure de ctiaiix; Sp, tlipochlnritD de c»t.
A honiogenouii, dull-white, granular powder, possessing an
alkaline reaotion, the odor of hypochlorous acid rather than of
uhlorine, and becoming moist and gradually decomposing oa
exposure to the air.
In its composition, chlorinated lime is commonly regarded as a
mixture of calcium hypochlorite and chloride, together with
undecomposcd hydrate, and its formation represented by the
equation :
2Ga(OH), -I- 2C1, - Ca(OCl), + CaCl, + 2n,0.
With reference, however, to the amount of available chlorine
which can be obtained from a perfectly saturated product, it may
be considered, with a much greater degree of probability, as con-
sisting of a mixture of a basic salt (calcium hydroxy -chloride),
with calcium chloride; and its formation expressed by the
equation :
3Ca(0n),+ 2CI,-2C:i<^QPj -t- CaCl,-H2H,0.
In contact wilh water, the calcium chloride dissolves, and the
basic salt is decomposed, with the f()rmaliou of calcium hypochlo-
rite and hvdrate, as follows:
■'\oci
, /on
'•\0H
,/oci
'"xoci-
CALCIUM. 297
When exposed to a gentle heat, chlorinated lime is converted,
according to its composition and the temperature, into calcium
chlorate and chloride, and, at a higher temperature, by de-
composition of the chlorate, yields oxygen, and probably also
some chlorine; by the action of sunlight, it is partially decom-
posed with the formation of calcium chlorate and chloride, and
the liberation of oxygen. When well mixed with ten or more
parts of water, it forms a creamy liquid, while its soluble con-
stituents enter into solution, leaving behind calcium hydrate, and
the insoluble impurities of the lime employed in the manufacture
of bleaching-powder ; the filtered solution is colorless, and of an
acrid, nauseous taste, changes red litmus for a moment into blue,
and decolorizes it almost at once, and completely ; it emits the
odor of chlorine with acids, and forms a white precipitate with
sulphuric and oxalic acids.
By the decomposition of chlorinated lime with acids the entire
amount of contained chlorine is available, as shown by the follow-
ing equations :
(1) CaCl, -h Ca(OCl), -f 4HC1 - 2C1, -f 2CaCl, + 2H,0.
(2) CaCl, + Ca(OClX + 2H,S0, « 2C1, -f 2CaS0, + 2H,0.
Chlorinated lime, exposed to the carbonic acid and moisture
of the air, evolves hypocblorous acid, which, when free, readily
breaks up into water, chlorine, and chloric acid ; the latter is also
soon resolved into oxygen, water, chlorine, and perchloric acid; a
deliquescent residue, consisting of calcium hydrate, carbonate, and
chloride, forms the final residual product. Upon this decomposi-
tion, or by the direct elimination of chlorine through the agency
of stronger acids, depends the energetic chemical action of chlori-
nated lime as an oxidizing agent, which, therefore, is proportionate
to the percentage of calcium hypochlorite, or, in other words, of
the available chlorine, which, for most pharmaceutical and thera-
peutical purposes, should amount to 25, or, as the minimum, 20
per cent. In order to estimate this, and to determine the value
of commercial bleaching-powder, several methods of testing are
employed, among which the following two are simple and reliable :
I. 1.96 parts of pure crystallized ferrous sulphate are dissolved
in a capacious glass flask in a mixture of 20 parts of water and 5
parts of hydrochloric acid; 1 part of chlorinated lime is then
thoroughly mixed, by trituration in a mortar, with 50 parts of
water, and the mixture added at once to the solution of the fer-
rous salt. The flask being then tightly closed, it is actively
agitated for a few minutes, and the mortar in which the chlori-
nated lime was triturated, subsequently rinsed with a little water,
and this liquid added to the contents of the flask. After again
agitating for a moment, the liquid should still retain the odor of
chlorine, and, after filtration, when tested with a few drops of a
298
NUAL OP CHEMICAL ANALYSIS.
solulion of potassium ferridoyaiiido, should afford no blue colora-
tion or precipitate.
This lest, when employed with the above stated proportions of
ferrous sulphate and chlorinated lime, will indicate a strength of
the latter corresponding to at least 25 per cent, of avaiUble chlo-
rine. With the employment of 1,57 parts of ferrous sulphate to
1 part of uhlorinflted lime, the application of the same test, which
is baaed upon the oxidation of the ferrous to ferric salt through
the agency of the liberated chlorine, will then indicate a strength
of the chlorinated lime corresponding to at least 20 per cent, of
available chlorine.
The United States Pharmacopoeia directs that if 0.71 gram of
chlorinated lime be mixed with a solution of 1.25 grams of potas-
sium iodide in 120 cubic centimeters of water, and 9 grams of
hydroohloric acid be then added, the resulting red-brown liquid
should require for complete decoloration not less than 50 cubic
centimeters of standard solution of sodium hyposulphite, corre-
sponding to at least 25 per cent, of available chlorine.
II. The following method of estimation will afford an accurate
result, when not alone the minimum, but the determination of the
exact percentage amount of chlorine contained in the chlorinated
lime ia desired. One gram of the chlorinated lime is triturated
in a mortar with a small portion of water until a uniform pasty
mass is obtained, which is afterwards further diluted with wat«r,
and, together with the rinsings of the vessel, transferred to a
graduated cylinder, provided with a glass-stopper
(Fig. 104), and the liquid finally diluted to 100 cubic
centimeters. The one per cent, solution thus ob-
tained, af^er being thoroughly mixed by agitation,
is allowed to repose until it becomes perfectly clear;
50 cubic centimeters of the clear liquid are then
carefully drawn off' by means of a pipette, and al-
lowed to flow into a solution of 2 grams of potas-
sium iodide in about 20 cubic centimeters of water,
contained in a beaker. To the mixed solutions
hydrochloric acid sufficient to render the mixture
slightly acid is added, and the liberated iodine
subsequently estimated by means of a standard
solution of sodium hyposulphite, page 9i. The
strength of the sodium hyposulphite solution, or the
amount of pure iodine corres|>ouding to one cubic
centimeter of the same, being known, the number of
cubic centimeters required to produce decoloration
of the liquid will indicate the amount of iodine libo-
raled by the chlorine, and therefrom, by simple
equivalent proportion (I, 127 — CI, 35.5), the arooant
of chlorine contained in the number of cubic oenti-
Fio. 104.
CALCIUM. 299
meters of the solution of chlorinated lime employed, from which
the percentage strength of the chlorinated lime in active chlorine
may be readily calculated.
In consequence of the facility with which chlorinated lime
undergoes decomposition, particularly by exposure to the air and
moisture, the amount of active chlorine contained in the commer-
cial article is often found to vary from 10 to 35 per cent.
CALX SULPHURATA.
CALCIUM 8ULFURATUM.
Sulphurated Lime. Oaleium Sulphide.
Ger. Schwefelkalk ; Fr. Salfore de calciam ; Sp. Sulturo de calcio.
Pure calcium monosulphide, CaS, forms a white or yellowish-
white mass, which is very sparingly soluble in water, and in
moist air d *velops the odor of hydrogen sulphide. As prepared
by the reduction of calcium sulphate with carbon, or by the
ignition of a mixture of caustic lime and sulphur (Calx Sul-
phurata,U. S. P.), a grayish or reddish-white mass is obtained,
which is not a definite chemical compound, but consists of a mix-
ture of calcium sulphide and polysulphides, with small and vari
able amounts of calcium sulphate, and carbonaceous matter or
other impurities.
Calcium sulphide is dissolved to but a small extent by water,
and, upon boiling therewith, is partially decomposed, with the
formation of calcium hydrate and sulphydrate: 2CaS 4- 2H,0 —
Ca(HS), -f Ca(OH)j. The solution is at first colorless, but, on
exposure to the air, becomes decomposed, with the absorption of
oxygen and carbonic acid gas, and acquires a yellowish color; it
possesses an alkaline reaction, and the (xlorof hydrogen sulphide,
which latter gas is abundantly developed therefrom upon the
addition of an acid.
Calcium sulphide, when shaken with water, and the liquid fil-
tered, should yield a solution which is not precipitated by solution
of calcium sulphate, but affording upon the addition of solu-
tion of ammonium oxalate a white precipitate, soluble in hvdro-
chloric, but insoluble in acetic acid. It should dissolve in dlilute
hydrochloric acid, with the abundant development of hydrogen
sulphide, and without leaving a ct'msiderable insoluble residue.
The presence of at least 36 per cent, of pure calcium sulphide
in sulphurated lime may be ascertained by gradually adding 1
gram of the salt to a boiling solution of 1.25 grams of cupric sul-
phate in 50 cubic centimeters of water; the mixture is then
heated nearly to boiling for about ten minutes, and, when cold,
filtered. The filtrate, when tested with one drop of test-solution
of potassium ferrocyanide, should remain colorless.
UANUAL OP CUBUrCAL .
CAMPHORA MONOBROMATA.
mphor MonubromicU.
Ger. M onobrom camp lie r
C„U„BrO; 230.8.
Thin, colorless prisms, when crystallized from alcohol, or elon-
gated, flat prisms, which are perfectly transparent and hard, when
cryslallized from petroleum benziii. It is permanent in the air;
not aflfectcd by direct sunlight; elowly volatilized when boiled in
water, and possesses an odor reminding of Borneo camphor, and
a taste whicn is lercbinlhinate and scarcely bitter. It fuses at 65
C. (149° F.), and boils at 274° 0. (525.-2^ F.), with partial decompo-
sition ; it does not sublime at ordinary temperatures, but sublimes
abundantly at temperatures above its fusing-point, in the form of
lonp, slender, colorless needles,
Hunobromaied camphor is almost insoluble in water, and spar-
ingly soluble in glycerin, but freely in alcohol, although leas bo
than ordinary camphor, and is readily dissolved by ether, chloro-
form, carbon bisulphide, warm petroleum benzin, and the volatile
and fatty oils; it is also soluble in cold, concentrated sulphuric
acid, and is precipitated unchanged upon the addition of water.
In alcoholic solution, in contact with sodium amalgam or
argentic nitrate, it is converted into ordinary camphor; and,
when boiled with a solution of argentic nitrate in dilute nitric
acid, it is decomposed, with the formation of argentic bromide,
corresponding in amount to 81.2 per cent, of the monobromated
camphor employed.
CAHTHARIDINUM.
Flo. I0.1.
Ger. CBUtlinridin 1 Fr. CaulUuridine ; Sp. Cantftriditia.
C„H„0.; 196.
Bright, colorless, rhombic prisms or laminie (Fig. 105), per-
manent in the air. When heated to 210° C. (410^ F.) ihoy soften,
and fuse at 218^ C. (424.4° F.); at higher
lemjieralures, by the cautious application
of heat, they may be sublimed unchanged.
Cantharidin is soluble in 30,000 parta
of cold, and half that amount of boiling,
water, and sparingly soluble in cold alco-
hol and carbun bisulphide, but quite
readily soluble in hot alcohol, and in
chloroform, ether, acetic ether, beazol, and the volatile and fatty
oils, particularly upon warming.
CARBONEUM. 301
When digested for some time at about 100° C. (212° F.) with
a dilute solution of potassium or sodium hydrate, it is converted,
by assimilation of the elements of water, into cantharidic acid,
CjjjHjgO^, or C^HgOj, which combines with the alkali with the for-
mation of well crystallizable salts. The aqueous solution of these
salts possesses an alkaline reaction, and, upon the addition of a
stronger acid, cantharidic acid is separated, but becomes, by the
elimination of the absorbed elements of water, immediately re-
solved into cantharidin.
When heated with hydriodic acid of the spec. grav. 1.8, can-
tharidin is gradually converted into the crystallizable, monobasic
canthan'c acid, which has the same composition as cantharidin ;
it is soluble, however, in 120 parts of cold, and 12 parts of boil-
ing, water, very soluble in alcohol, sparingly in ether, and does
not produce vesication when its solution in glycerin is applied to
the skin.
Cantharidin is an active poison, and, when applied to the skin,
exerts powerful vesicating properties, which, for the want of any
distinguishing chemical tests, may be employed as a means for its
identification.
For the separation of cantharidin when associated with alka-
loids or other organic j>rinciples, see page 106.
CARBONEI BISULPHIDUM.
CARBONEUM 8ULFURATUM. ALCOHOL 8ULFURIS.
Bisulphide of Carbon. Carbon Bisulphide,
Ger. Schwefelkoblenstoff ; Fr. Sulfure dc carbone; Sp. Bisnlfuro de carbon.
CS,; 76.
A transparent, colorless, very volatile liquid, of great refrac-
tive and dispersive power, of a pungent, somewhat aromatic
taste, and a peculiar odor, which, when pure, slightly resembles
that of chloroform. Its spec. grav. is 1.272 at 15° C. (59° F.),
and it boils at 47° C. (116.6° F.), but does not solidify when ex-
posed to a temperature of — 110^ C. (—166" F.). It is highly
inflammable, taking fire in the air at 149° C. (300.2° F.), and
burns with a blue flame, yielding, as the products of combustion,
carbon dioxide and sulphur dioxide. Its vapor, when mixed
with one-third of its volume of oxygen or atmospheric air, forms
an explosive gas, which detonates with great violence in contact
with flame; when mixed with nitric oxide, its vapor burns upon
ignition with a very bright blue flame, which is particularly rich
in chemically active rays.
Carbon bisulphide is not dissolved to any appreciable extent
302
MANUAL OF CHEMICAL i
by wal«r, and sinks in that liquid ; when agitated with iodine-
water, it absorbs the minute quantity of iodine dissolved in the
water, and acquires a faint, purple color.
Carbon bisulphide in remnrkable and important on account of
its extensive eolvent powers; it is miscible, in all proportions,
with absolute alcohol (the solubility decreasing with the decrease
of strength of the alcohol), with elher, chloroform, benzol, essen-
tial and fatty oils; it dissolves readily and freely, among other
substances, sulphur, phosphorus, bromine, iodine, iodoform, cam-
phor, caoutchouc, gutta-percha, many resins, wax, paraffin,
stearin, chloral hydrate, and many alkaloids which are soluble in
ether and alcohol.
The vapor of carbon bisulphide is a jrawerful anti -putrescent,
and retards fermentation, but is also an active poison when in-
haled in large quantity, and is capable of producing very serious
effects when inhaled for a considerable time, even in very 8mall
amount. By exposure to sunlight, carbon bisulphide becomes
partially decomposed, acquiring a disagreeable odor and a yellowish
color; It then contains sulphur in solution, and reddish-brown
flocks of polymeric carbon inonosulphide (CS), are separated.
When preserved under water, it also acquires a yellowish color,
with the formation of small amounts of carbonic and sulphuric
acids, and, when heated with water in a sealed tube, at 150** C
(302° F.), it is further decomposed with the formation of bydro-
■ gen sulphide.
■ Carbon bisulphide may be recognized, even in very minute
I quantities, by warming it in a closed fiask witb
^^ Fio. 106. concentrated amnion in- water, or by mixing it with
^H f^^Th ^ little ammoniacal alcohol and gently heating;
^B V^^ these liquids furnish, upon evaporation on iTie
^M^^^ niT water-balh, a residue consisting of ammonium sul-
^^^^^■^ rll pbocyanide, which, when dissolved in a little water,
^^^^^^fe :" and a drop of solution of ferric chloride added,
^^^^^^p! :« yields the characteristic blood-red color of ferric
^^^^^" Bulphocyanide.
^P i" ExamiDatloQ :
H^ > The odor of carbon bisulphide should not be re-
^^^^^ 1^ pulsive, nor fetid; it should not cause a dark tur-
^^^^^^ bidity or precipitate in a solution of plumbic acetate,
^^^^^B :" when agitated with it (absence of hydrogen sul-
^^^^^H If, phide), nor change the color of moist litmus-paper
^^^^^^L (absence of sulphurous acid), and, when allowed to
^^^^^K, E" evaporate s[^iontaneously upon a watch-glass, should
^^^^^K Jm leave no residue (absence of free sulphur, or other
^^^^B^ impurities).
^P An admixture of ethyl or methyl alcohol may
H tf 8 b readily be detected by the lesser specific gravity of
L '""
CERIUM. 803
fatty oils, and bv its diminution in volume when shaken, in a
graduated cylincfer (Fig. 106), with an equal volume of water or
glycerin.
CERII OXALA8.
CERIUM OXALICUM.
Oxalate of Cerium, Cerium Oxalate,
Ger. Ceroxalat ; Fr. Oxalate de cerium ; 8p. Oxalato de cerium.
Ce,(C,OJ, + 9H,0 ; 708.
A white, granular powder, without odor or taste, containing 9
molecules (22.88 per cent.) of water, and permanent in the air; it
is almost insoluble in water, alcohol, ether, chloroform, and solu-
tions of potassium or sodium hydrate, but soluble in hydrochloric
and sulphuric acids. Exposea to heat, the salt is decomposed,
and at a dull red heat is completely converted into cerosoceric
oxide, Ce,0^, which is of a dark-red color when hot, yellowish-
white when cold (a brown color would indicate the presence of
didymium), and soluble without effervescence in boiling hydro-
chloric acid; this solution gives, with an excess of a saturated
solution of potassium sulphate, a crystalline precipitate of potas-
siumcerous sulphate, 3K,S0^ -f Ce,(S0j8.
Cerium oxalate, when heated with a solution of potassium
hydrate, filtered, and the filtrate neutralized with acetic acid,
affords upon the addition of a solution of calcium chloride a
white precipitate of calcium oxalate, which is insoluble in acetic,
but readily and completely soluble in hydrochloric acid.
Examination :
Earthy carbonates are indicated by effervescence of the salt with
hydrochloric acid.
Soluble salts may be readily detected by digesting the cerium
oxalate with water, filtering, and evaporating the filtrate to dry-
ness; any considerable residue, upon evaporation, will reveal the
presence of such impurities.
Alumina or aluminium salts may be detected by boiling the
oxalate of cerium with a strong solution of potassium hydrate,
filtering, and adding an excess of solution of ammonium chloride,
when a white, flocculent precipitate of aluminium hydrate will be
formed, if such be present.
Other impurities, such as metallic oxides, insoluble earthy
phosphates, foreign oxalates, etc., may be sought for, when indi-
cated, according to the systematic methods of analysis, as
described on pages 51 to 61.
804 MANUAL OF CHEMICAL ANALYSIS.
CHINOIDIinTM.
Chinoidin, Quinoidin,
Ger. Chinoidin ; Fr. Quinoidine ; Sp. Qoinoidina.
A brittle, resin-like mass, of a deep brown color, a glossy, con-
choidal fracture, and a i)eculiar aromatic odor, and consisting
principally of diquinidine, C^H^N^O, accompanied by varyine
amounts of quinicine, C^H,^N,Oy cincbonicine, C^^H^XjO, and
other amorphous bases ; it becomes soft and tough at a moderate
temperature, and melts like a resin when warmed; at a stronger
heat, it burns away, and leaves, upon incineration, a white ash,
which should not amount to more than 0.7 per cent, of its weight.
Chinoidin is almost insoluble in water, and only partly soluble
in ether, benzol, and in glycerin, but freely soluble in diluted
acids, in alcohol, and in chloroform, forming dark brown solutions
of an aromatic, bitter taste and tnlor; the alcoholic and ethereal
solutions are precipitated by water, and the acid aqueous solution
becomes green when lirst mixed with sufficient chlorine- water to
decolorize it, and subsequently with an excess of ammonia- water.
Examination :
G\im'R*'s»ns, — A small portion of the triturated chinoidin is
agitated, in a test-tube, with about 20 times its weight of water;
the mixture is then heated to boiling, with constant agitation;
when c*»l. the water must be nearlv colorless, and remain so
uj>>n the addition of a few drops of a concentrated solution of
pota.-sinm hydrate, and subsequent heating: if a brown colora-
tion takes j»]ace; in cither of these tests, gum-resins ^^aWs) or
«»ther soluble admixtures (liquorice, gluc«)se, dextrin, etc.) are
ind:t.-:t!ed.
R'.>)i< may Ix- detected in the chinoidin remaining undissolved
in xi'.K' vrcLviincr test, bv dissolving it, with the aid of heat, in
dilute-i su'.iLnric acid: a complete or almost complete solution
mu<: Take plaLV. otherwise an admixture ol resins, insoluble in
di. 11 :♦.'-.: acids, is indicated.
A> a 0'"»!.!:rin:it'''rv test f-T ffum-rosins, liounrice. glucose, etc. a
lew -irvi'S *^\ t':e obtair.ed so.ution mav K* alloweii to fall into
ale ».:■•-: tiicv must form a clear .solution: an ensuing turbidity
w- •'.;..♦ ts: :/!.«>!>:: t':*e preseTice oi such admixtures.
/'; »• • ■ »r , '. • • T -r u \x t u ?•' > a re i i id i ca t ed \ y an i n s* > * uble residue
whv!; ::.♦.• •"■.:: 'i'-i-.n is iiss-'lvt-d in a'.coLol. or bv a residue left
t • « I
'.',.-- i:.\\ Iv sf'ccia'.y soMght lor in the residue left upon
♦ Ir. c 'cvfq^^frce of "L*- s'ow conibuiilion of ilie suHtnnce, its complete
iirr.-/' L may U lac./TiK-d by tin: add! lion of a Irw Jn^ji* of nitric acid to the
oxrS :,i ^ou* r-*'iu<^ !• f; ufi^-n heating, and ajain stiongly beatiug, wlien the
orgai:-v n*a::tr n:''. l*\^»me ct^nipltttiv rt-nu»vt>i.
CHLORALUM. 305
ignition, by dissolving it in a few drops of warm hydrochloric acid,
and, after dilution with water, testing the solution in separate
portions, with a drop of solution of potassium ferrocyanide, and
with an excess of ammonia-water ; a reddish-brown turbidity with
the first-named reagent, and a blue coloration of the liquid with
the latter, will determine the presence of copper.
CHLORAL.
CHLORALI HYDRAS. CHLORALUM HYDRATUM.
Chloral. Hydrate of Chloral. Chloral Hydrate.
Ger. Chloral by drat ; Fr. Hydrate de chloral ; Sp. HIdrato de cloral.
C,HC1,0 -f H,0 - CCl3-CH<^Q^ ; 165.2.
Colorless, semi-transparent, needle shaped crystals, or crystal-
line plates, belonging to the monoclinic system, and possessing a
peculiar ethereal odor and pungent taste. Exposed in a dry test-
tube to a gentle heat, by dipping the tube into hot water, chloral
hydrate fuses at 58 ^ C. (136.4° F.), forming a clear, colorless liquid
of the spec. grav. 1.575, which, at 46° C. (114.8° F.), again solidi-
fies; at 78° C. (172.4° F.), it is resolved into chloral, which boils
at 99° C. (210.2° F.), and water, and, at a higher temperature, is
wholly volatilized, without the evolution of inflammable vapors.
Chloral hydrate is soluble in about half its weight of cold water,
and freely in both alcohol and ether, but only sparingly .soluble
in CO W chloroform, in carbon bisulphide, in benzol, benzin, and in
fixed and volatile oils. Its aqueous solution possesses a faintly
acid reaction, but, when slightly acidulated with diluted nitric
acid, no change, or but a faint opalescence, should be produced
upon the addition of solution of argentic nitrate; upon the sub-
sequent addition of a little ammonia- water, however, and heating
the mixture, decomposition takes place with effervescence, and
with the formation of argentic chloride and metallic silver, the
latter coating the walls of the tube. When the aqueous solution
is acidulated with diluted sulphuric acid, and faintly tinged with
a few drops of solution of potassium permanganate, no decolora-
tion should take place within a few hours. The alcoholic solution
of chloral hydrate, in distinction from the aqueous, should not
affect the color of moistened bine litmus-paper, and should also
afford no turbidity upon the addition of a solution of argentic
nitrate.
Concentrated sulphuric, nitric, and hydrochloric acids dissolve
chloral hydrate witn decomposition, but without color, and with-
out the evolution of colored vapors. Solutions of the alkaline
20
306
MANUAL OP CHBUtCAL ANALYSIS.
soluble form
hyflratee dci^ompose it, when heated,
uliloroform. Ammonium sulphide dissolves chloral hvdraie, witli
the evolution of heat, forming a. turbid, reddish-brown lirjaid;
the same reagent produces, in concentrated as well as in iliiiiie«l
solutions of chloral hydrate, a yellow coloration, which becomes
dtirk brown, forming, with the separation of sulphur, a reddish-
brown coni|>ouiid, gradunlly when cold, immediately apon
warming.
Chlontl hvdralc liquefies when mixed with carbolic acid or
with camphor, without decom position, and is separated again by
ihc subsequent addition of water.
£xuniiiatioD :
Decomposition of chloral hydrate is indicated by the emtssioo
of vapt»rs and bv a pungent odor ujion opening the vial, by the
reddening of moistened blue litmus-paper when immersed in it,
as also by a yellowish color and incomplete solubility in water,
with the formation of oily drops. Ii is further indicated, in
the aqueous solution of chloral hydrate, acidulated with a few
drops of diluted nitric acid, by a white )ireci)iilate with atomic
nitrata, and in another portion, acidulated with sulphuric acid, by
deooloratiun of solution of potassium i<ermanganate.
C»foniUfc»Ao/n/f,C^Cl,0+C,H.O - (CCl.-CH^^H^*^'), is
disttngui^ed from the hydrate by the e%'olntion, upon atrooglj
heating, of inflainiii.tble vapors, which burn with a yellowish,
smoky flame : by the property of being readily and freely solnbte
ia n>jiif chloroform, in carVxHi bisulphide, or tn oil of inrpeatine,
bat less soluble in cold water than is the hydrate; and by its
yielding a rvddish-brown or brown solution with warm coiioei-
tratcd sulphuric acid, and by the erohitioo
Fk. m. of red nitrous vapors with concentrated
nilrie acid.
y""'^ ~"^ An admixture of the alooholate with the
I /iNrt-^KT "^X hydrate may be detected by disaolviiq; a
^^^^H J^S?[iglA <j portioQ of the salt in about 10 times iU
^^^^H fs^O' '^^ T weight of water, in a te^tinbe, addii^sBf-
^^^^^K W, ^^ aQf ficient of a satiation of iodiniaed pnliiiiiiiii
^^^^^^ \. ^^V^ ^^ iodide to impart a dark brown eolorattoo,
^ ^^_^^^ *»i sqhseqoenilv % sotirtioa of poiaseiani
H bydrate, in small ikirt:ooK, aotil the liquid
H ts Bcarlr deeolomnl aad rvtaina Imi a
H i£^K y&cmiA tmt : the mixture U tb«« gnuly vanacd^ bj im-
H mKltaa% tW lest-labe fbr a ^ort titoe >■ hot' water, aod sabo*-
H q— tly allowed to cuol ; if eblon) aJcoboUte is presral, —all
H y^awciTStals of iodoform (Tig. t07t will be xpantcd, arbieh
^1 Majba moFwnd br titeir udnr, and ih«ir appeatmac* oadrr ifce
^1 ■■'■■■mnii, wbilst t^ Hqnid. in coosniiurnee of lb« i
H Lblwaftw. win MTfT a milkJikc laHuditT.
\
CnLOBAHlM. 307
The following raethodB of approximate estimation of the purity
of chloralhydrate depend upon the volnmetrio determination of
the quantity of chloroform produced by the decomposition of a
known quantity of chloral hydrate, or upon the determination of
the amount of normal alkali which is required for the complete
(J ecom position of the salt into chloroform and an alkaline for-
miate :
C,nCl,0 + II,0 + NaHO = n,0 + NaCHO, + CHCl,
Chloral hydrate. Sodium Ibrmiate. Chlororonn.
I. Fifty parts of the chloral hydrate are dissolved in about an
equal weight of water in a graduated glass tube or cylinder,
divided into 100 parts {Fig. 108); a warm solution
of potassium or sodium hydrate (containing about
20 parts of potassium hydrate, or 15 parts of sodium
hydrate) is then added, and, finally, Kufiicient water
to make the entire liquid measure 100 parts. The
cylinder is then closed, agitated for a short time, and
allowed to repose, when the fluid will soon separate
into two layers, a lov/er one of chloroform, and an
upper la^'er, consisting of an alkaline solution of
potassium or sodium formiate.
If the sample was pure hydrate, the chloroform
should measure not less than 24.0rt parts, correspond-
ing to 36.10 jjarts by weight, or 72.2 per ctjnt. of the
chloral hydrate employed ; if it was chloral alcohol-
ate, the chloroform will measure 20.53 parts, corre-
sponding to 30.88 parts by weight; or 61.75 per cent.
of the chloral alcoholato.
An admixture of the alcoholate with the hydrate
will, therefore, be indicated, proportionately, by the
decrease of the quantity of chloroform, ranging, in
the above test, between 24.06 and 20.53 parts by
volume, and 36.10 and 30.88 parts by weight.
II, About 3 grams of chloral hydrate are accu-
rately weighed, and dissolved, in a beaker, in about 10 cubic cen-
timeters of water ; the solution being then gently warmed, about
25 cubic centimeters of a normal solution of potassium or sodium
hydrate (page 87) are allowed to flow in from a burette, when the
chloral hydrate will become completely decomposed iuto chloro-
form and potassium or stHlium formiate. To the cooled liquid a
few drops of u neutral solution of litmus are then added, and the
exoess of alkali (18.12 cubic centimeters of normal alkali are
theoretically required for the decomposition of 3 grams of chloral
hydrate) inversely titrated by means of a normal solution of
oxalic acid, page 82. Tlie number of cubic centimeters of the
uurmni acid which are required for the exact neutralization of
SOS MANUAL or CHEMICAL ANALYSIS.
the liquid, subtracied from the number of cubic ceDtimetcn o
normal alkali originally einploye'l, will indicate the amount of
alkali required for ilie decomposition of the chloral hydrate, and
therefrom the purity of the salt may be readily determined; one
cubic centimeter of normal alkali corresponding tu 0.]t>5d gram
of pure chloral hydrate.
If the chloral hydrate contains alcoholate, the number of cubic
centimeters of alkali required to efleut the decomposition of the
salt will be less, and in proportion to the extent of the admix-
ture ; 3 grams of chloral alcoholate requiring for its decompoailioa
15.50 cubic centimeters of normal alkali.
CHLORALUM BUTTLICUM.
BUTTLU-CllLORALUM HYDRATUM. CRdTOSO-CHLORALUM
IIYDRATUM.
Sutyt-ehloral ffgdntlt. Cmlnn-ektaraJ Hydrate.
Oer. Butflchlontlliydmt -, Fr. Hydmie de cliloral butytiqne ;
Sp. Hldmto <te clnral-cminD.
C,H,CI,0+ H,0; 190.2.
Thin, white scales, of a silky lustre, fusing at 73" C. (172.4'
F.). and readily volatil^z'ng above that temperature, with the
evolution of irritating vapors.
Butyl-chloral hydrate in soUible in about 20 part.iof coH water,
and readily soluble in boiling water, in alcohol, and in glycerin;
it volatilizes freely with the vapftrs of boiling water.
Its solution should be neutral in its action upon litmus, and
affords no turbidity when tested with solution of argentic nitrate.
" Upon gently heating with concentrated sul]thuric acid, hnlyl-
chloral hydrate should remain colorless, and form oily drops of
colorless butyl chloral. It i.« decomposed by alkaline hydrates,
forming bichlorallvlene (C,H,C1J, and alkaline formiate and chlo-
L ride.
k
I ethe
I litm
Hi
CHLO ROFORMTTM.
CHLOROFORMUM.
CMoTfform.
Ger. Cliloroffinn ; Fr. CUtoroforme ; Sp. Clornformo.
CHClj; 119.2.
A dense, colorless, volatile, and limpid liquid, of an agreefiUs,
ethereal, aromatic odor, and sweetish taste; it does not act upon
litmus, and is not readily inflammable, but. when a wick is satu-
CHLOROFORMCM. 809
rated with oliloroform, and ignited, it burns with a greenish flame,
emittitig pungent vapora which ooutain hydrochloric acid. It is
very volatile at common temperatures, producing, by rapid evap-
oration, great cold, and leaving neither a residue, nor a film of
moisture, nor any unpleasant odor, when wholly evaporated by
the warmth of the hand, by causing the chloroform to flow to and
fro, in a porcelain capsule. It boils at 62° C. (143.6° F.).
Chloroform sinks in water, being but slightly soluble, one part
requiring about 200 parts of water for solution. Tbe spec. grav.
of pure chloroform is 1.502 at 15° C. (59° F.); in this state uf
purity, it is subject to rapid decomposition by the combined
action of atmospheric oxygen and of solar light; it is, however,
protected against this deterioration by a slight percentage of
cthvHc alcohol, which is, therefore, retained in the preparation of
medicinal chloroform, or subsequently added thereto in amounts
of from one to two jier cent., whereby ils specific gravitv ia
decreased from 1.4854 to 1.4705 at 15°C.(59^ F.), and its toil-
ing-point, despite the higher boiling-point of pure alcohol, reduced
in tho first instance, from 60.2 to 61.6" C. (U0.3 to 141.8^ F.),
and, in the latter, from 59 to 61.2" C. (138.2 to 142.1'=' K).
Chloroform is raiscible, in all proportions, with absolute alco-
hol, with ether, benzol, carbon bisulphide, and fixed and volatile
oils, and is an extensive solvent for resuis, caoutchouc, gutta-percha,
canjphor, paraflin, etc. ; it also dissolves iodine, bromine, and, more
or less completely, most vegetable alkaloids, which latter it almost
completely withdraws froin their aqueous, alkaline sulutiuns.
Chloroform is not miscible with glycerin, and is insoluble in
the concentrated mineral acids; when shaken wilh them, even at
an elevated temperature, it undergoea no perceptible change ; nor
is it acted upon at ordinary temperatures by aqueous solutions
of the alkaline hydrates, iodides, or bromides, nor by argentic
nitrate.
When healed with an alcoholic solution of potassium or sodium
hydrate, it is decomposed, with the formation of alkaline chloride
and formiate;
CHCl, + 4NaH0 = 2IIp + 3NaCl + NaCHO,.
On the subsequent addition of a little water, and the evajwra-
tion of the chloroform and alcohol, the liquid, when exactly neu-
tralized by dilute sulphuric acid, will yield a white precipitate
upon the addition of a solution of argentic nitrate ; if the fil-
trate therefrom be then gently warmeil, a reduction of the argen-
tic nitrate will take place, and a silver mirror obtained on the
sides of the tube. When heated to 180° 0. (856^ F.) with an
aqueous or alcoholic solution of ammonia, it is resolved into am-
monium chloride and cyanide; and, in the presence of a little
potassium hydrate, the decomposition takes place below 100° 0,
(212° F.):
CHCl, + NH, + 4KII0 = 411,0 -I- 3K:C1 -J- KCN.
810 HANDAL OP CIIKHICAL ANALVStS.
The liquid, upon ibe subsequent addition of a few drops of a
solution of a ferrous and ferric salt, and supersat oration witli
Lydroclilorit; acid, will yield a precipitate of Prussian blue.
When chloroform, or its aqueous or alcoholic solution, is gently
heated with an alcoholic solution of sodium hydrate, and a few
drops of aniline, vapors of phenyl-isocyanide (pnenylcarbylainin),
CgHj-NC, are evolved, which possess an exceedingly penetrating
and unpleasant odor, and produce insensibility when inhaled.
CHCl, + 3NaH0 + C.H,(NH,) - C^H.-NC + 3NaCl + 3H,0.
When chloroform, or its aqueous solution, is warmed with an
alkaline solution of cupric tartrate (Fehling's solution), a sejiara-
tiou of red cuprouH oxide is produced, in consequence of the for-
mation of a trace of sodium formiale.
Examination of Commercial Impure and of Fmified Chloroform:
As a j<reUifnm'ry lest for the indicittiim uf a partial decomposi-
tion of chloroform, a test-lul>e iiiiiy be rinsed with ammonia-
water, and, subsequently, one or Iwo drops of the chloroform
allowed to fall to the bottom of the tulre; the appearance of
white fames would indicate such decomposition. In another test-
tube equal volumes of the chloroform and of water, the latter
slightly blued with neutral litmua-Holution, are shaken together;
n decoloration or a red appearance of the water, after subsiding,
would likewise show decomposition.
The result of these tests should also be negative, if the chloro-
form has been previously exposerf, in a white glass bottle, to
direct sunlight, for about ten hours.
When shaken with half its volume of concentrated sulphuric
acid in a bottle closed by a glass stopper, no coloration should be
produced, either at once or upon standing; a dark coloration of
either liquid will indicate a partial decomposition of the chloro-
form, attended by the liberation of chlorine, which, combining
with the ethylic or other alcohols which may be present, gives
rise to the formation of chlorinated ethers, which impart a brown
color to the sulphuric acid.
Chlorine and Hydmchhric Acid. — Two volumes of chloroform
are shaken in a graduated cylinder (Fig. 109) with one volume
of water, A perceptible diminution of the volume of the chloro-
form, after subsiding, would indicate an objectionable percentage
of alcohol. The supernatant water must neither appear tarbtd,
nor redden blue litmus-paper, nor atlbrd a precipitate when tested
with a dilute solution of argentic nitrate. An acid reaction upon
litmus, and the occurrence of a precipitate with the latter reagent^
would indicate free dilorine or hydrochloric acid.
Chlorine may also be detected by adding the chloroform, drop
by drop, to a solution of potassium iodide (free from iodate) ia a
test-tube. When agitated, the chloroform, after subsidhig, will
apjiear rose-colored, and the aqueous solution yellow, if even
CHLOROFORMnM.
311
traces of free chlorine be cotitiiined in the chloroform ; when this
is tlie case, and the iidditioii of chloroform, in drops, is continued,
each drop, falling through the aqueous solution, will nssume a
sliglil purplish tint.
Ethylene dickloride (Dutch liquid), CjH,CI,, will l>e indicated
by its lower specific gravity (1,247 at 18° C. — l'}iA° P.), ami
higher boiling-point (S6° C.~185^ F.), as also by the
following teat: A little fused potassium hydrate is Fio. lOe.
dissolved, in a dry test-tulie, in some absolute aloo- /(T^
hoi; after complete solution is eflected, and the im-
puriliea have subsided, the clear liquid is decanted
into a dry t«st-tubo, and a little chloroform added.
No reaction wilt take place in the clear Huid unless
the chloroform contains Dutch liquid, in which case
an elevation of temperature will appear perceptible
by a small thermometer immersed in the liquid ; a
slight evolution of gas from the liquid will also
c)ccur, and a crystaHine precipitate of potassium
chloride will be gradually produced.
Alfohol. — Since medicinal chloroform, as staled
above, contains about one or two per cent, of alcohol,
an examination for an admixture of alcohol by one
of the following sensitive tests would obviously be a
contrndfetio in adjeeto. The specific gravity, tlie vol-
umetrio test in the preceding examination, and the
property of chloroform to form a perfectly clear an<i
transparent mixture with sweet oil of almonds, which
it will not do if it contains more than five or six per
cent, of alcohol, afford sufficient evidence of the
quality of chloroform in this respect, A chloroform which has a
specific gravity of less than 1.4705 at lo"' C. (59° P.), and which
renders oil ot almonds turbid, and causes a perceptible rise of
temperature when actively shaken, in a dry test-tube, with an
tiqual volume of concentrated sulphuric acid, cannot be considered
as being of medicinal strength.
Tests for Ihe Detection of Alcohol in Chhrofnrm.
1. Strong sulphuric acid, to which a little potassium bichro-
mate has been added, when shaken with an equal bulk of chloro-
form, will turn green, if ihe latter contains alcohol.
2, Two volumes of cliloroform and one vtilume of concentrated
sulphuric acid are mixed in a botlle closed with a glass stopper;
after repeated agitation, the bottle is set aside for a few hours;
the liquid is then carefully diluted with about an equal bulk of
water, the supernutant aqueous liquid is decanted into a beaker.
and ao much of a mixture of pure barium carbonate in water is
added, with constant stirring with a glass rod, as ooinpSetely to
312
MANDAL OF CilBHICAL ANALYSIS.
neutralise the acid, so that, afr«r gentle warming, the cooled liquid
does not change blue litmus-paper ; it is then passed thruufrh a
moist filter, and the filtrate tested with diluted sulphuric acid. If
the chloroform contained traces of alcohol, this would have given
riae to the formation of ethyl -sulphuric acid (sulpbovinic acid),
and siibBequeiitly tu soluble barium ethyl-sulphate, contained in
the GIteren solution, and which is precipitated by sulphuric acid
as barium sulphate. Consequently, the occurrence of a white
precipitate will be evidence of the presence of alcohol.
3. A mixture of two volumes of the chloroform with five vol-
nmes of water is warmed in a test-tube to about from 30 to 40**
C. (86 to 104"^ F.); after active agitation for a few minutes, the
liquid is passed through a moist filter, and to the filtrate is added
a little solution of iodiuized potassium iodide; a solution of potas-
sium hydrate is then gradually added until the color of the liquid
disappears. Afier twelve hours' standing in a conical glass, a
crystalline deposit of iodoform (Fig. 110) will have taken place
if alcohol bo present; the crystals may be recognized under t
microscope, wlien the liquid is carefully removed by means of a
small pipette (Fig, 111), and the deposit transferred to a glass slip.
CHRTSAROBIITTTM.
Chrfiarobia.
Oer. CbryMrobin; Fr, Cbrysarobine ; Sp. Criurobin.
A pale, orange-yellow, crvstalline powder, without odor or
taste, and permanent in the air. When heated to 162° C. (323.6*
F.), it melts, and, at a higher temperature, may be partially sub-
CINCIIONIDINA. 31S
limeJ; whcD strongly heated on platinum-foil, it emits yellow
vapors with the separation of carbon, and is finally completely
dissipated.
CliryHarobin is almost insoluble in water, and sparingly solu-
ble in alcohol, but is quite readily soluble in ether, chloroform,
benzol, and the fixed and volatile oils; it is also soluble in solu-
tioDs of the alkaline hydrates, with a vellowish-red or reddish-
yellow color, which is changed to re^ by passing air through
the liquid. When shaken with ammonia-water, chrysarobin
assumes, after some hours, a fine carmine-red color. It dissolves
in cold concentrated sulphuric acid, with a deep blood-red color,
and on pouring the solution into water it is again separated un-
changed. If a little of the powder be strewn upon a drop of
fuming nitric acid, and the red solution exposed in a thin layer
to the action of the air, it then assumes in contact with ammonia
a violet color.
CIirCHOniDINA.
CINCHONIDINUM.
Giiiehcnidint. Cinehonidia.
Ger. Cinctioaldin ; Fr. CincIionldlQe ; 8p. Cinconidiiift.
C„H„N,0; 294.
Colorless, hard, shining prisms, odorless, possessing a bitter
tai>te, although le«s intense than that of quinine, and an alkaline
reaction. They contain no water of crystallization, and fuse at
208.5" C. (403.7° F.); wheu strongly healed upon platinmn-foil,
they become decomposed and charred, and are finally completely
dissipated.
Cinchonidine is soluble in 1680 parts of water at 10° C. (50° F.),
in 19.7 parts of 80 per cent, alcohol, and in 76.4 parts of ether;
it dissolves readily in diluted acids with the formation of neutral
and acid salts, which are mostly well crystallizable, more freely
soluble in water than the corresponding salts of quinine, and quite
readily soluble in alcohol, but very sparingly soluble in elher.
In contact with couccntraled nitric or sulphuric acid, cincho-
nidine suffers no change of color (distinction from brucine, mor-
phine, salicin, etc.). and its solution in the latter acid does not
afford a purple coloration in contact with a crystal of potassium
bichromate (distinction from strychnine").
When dissolved in water, acidulated with diluted sulphuric
acid, the solution displays no fluorescence, and, upon the addition
of a little chlorine water, and subsequently of ammonia, tin green
coloration is produced (distinction from quinine and quinidine).
It is distinguished from cinchonine by its greater solubility in
314
MANUAL OF ClIBMtCAL AI4ALTSI8.
eilier, the latter requiring at 17° C. (tS2.6^ F.) <i70 parts of e
for solution.
In the absence of any specially characteristic chemical lest for
einchonidine, its identity aa a cinchona alkaloid may be deter-
mined, in connection with the deacribed physical characters, by
its property of affording, when mixed with a little sui;ar, anii
liealed in a perfectly dry test-tube, a bright-red tarry sublimate,
which, aa far as at present known, is only produced by the dry
distillation of cinchona barks or their alkaloids, when in contact
with some indifferent organic substance, such as sugar.
When einchonidine is dissolved in water, acidulated with dilute
sulphuric acid, it responds to the teats for a solution of cinohu-
nidine sulphate, as described under the latter, on page 314,
CINCHONIDIHjE bulfhas.
CINCHONIDINUM SDLFUIllCUM.
Bulphat* oj OinehoaidiM or Cinehanidia. Ciimhonidint 8utphat».
Oer. Schwefelsaures Cluclionldln ; Pr. Sulfnte de cinchoaldlne ; Sp. Suirnto de
ciocnnidinA.
(C„H„N,0),.H^SO. + 311,0; 740.
Colorless, silky, lustrous needles, or thin quadrangular prisms,
without odor, but possessing a very bitter taste, and feebly alka-
line reaction. /I'hey contain about three molecules (7.30 per
cent.) of water oF crystallization when crystallized from n concen-
trated aqueous solution, or six molecules (13,(10 per cent.) wheu
crystallized froni a dilute aqueous solution. When heated to
100° C. (212° F.) the salt loses its water of crystallization, and
when atrongly healed upon platinum-foil it is decoraposefl and
charred, anJ finally completely dissipated,
einchonidine sulphate is soluble in 100 parts of water and in
71 parts of alcohol at 15° C. (59^ F.), in 4 parts of boiling water
and in 12 parts of boiling alcohol, freely soluble in acidulated
water, and soluble in 1000 parts of chloroform; but nearly in>
aolnble in ether and benzol. The aqueous solution possesses a
bitter taste, and is precipitated by the genera! alkaloidal reagenta:
potassio-mercuric iodide, platinic chloride, tannic acid, etc, and
upon the addition of solutions of the alkaline hydrates, carbon-
ates, or bicarbonatcs, a white precipitate of einchonidine is pro-
duced, which is nearly insoluble in an excess of the precipitant,
but soluble in about 70 times its weight of ether, and, upon stand-
ing, becomes crystalline; with solution of barium cnloride it
yields a white precipitate of barium sulphate, insoluble in hydro-
cbloric acid.
In contact with concentrated nitric or sulphuric acid, cinchoni-
IINCHONINA.
315
dine sulphate sufl'ers no cliangeof color (dialincliijn from brucine,
morphine, saliciu, etc.), and ita solution in the latter acid does not
afford a purple coloration in contact with a crystal of potassiitni
bichromate (distinction from strychnine).
The solution of cinchonidine sulphate in water, acidulated with
sulphuric acid, displays do fluorescence, and, upon the addition
of a little chlorine- water, and subsequently of ammonia, no green
coloration is produced {distinction from the sulphates of quinine
and quinidiue). It is distinguished from cinchonine sulphate by
the solubility of the latter in 60 parts of chloroform, whereas cin-
chonidine sulphate, as previously stated, requires 1000 parts of
chloroform for solution.
A cold saturated solution of cinchonidine sulphate affords, upon
the addition of a solution of potassium and stxlinm tartrate (Ro-
chelle salt), in slight excess, a white crystalline precipitate of cin-
chonidine tartrate, (C,,H„N.O),.C,H,Cf, + 2H,0, which requires
1265 parts of water for solution, and is quite insoluble in an
excess of the reagent.
Examination :
Mnuiur/'. or the verification of the proper amount of water of
crystallization, may be determined by exposing one gram of the
Kalt to the temperature of 100" 0.(212" F.), nutil the weight
remains constant; when thus dried the residue should weigh not
less than 0.92 gram, indicating an amount of water corresponding
to between three and four molccuica,
Cinchonine and Qmntdine Sitlphales. — In addition to the above
descrilied points of distinction, the presence of any appreciable
amount of cinchonine or quinidine sulphates may be readily
detected by the following test: 0.5 gram of the cinchonidine sul-
phate is digested with 20 cubic centimeters of cold distilled water,
0.5 gram of potassium sodium tartrate added, the mixture mace-
rated, with frequent agitation, for one hour, at 15° C. (59° F.),
then filtered, and one drop of ammonia-water added to the filtrate,
when not more than a slight turbidity should occur; a white
precipitate would indicate the presence of more than 0.5 per cent,
of cinchonine sulphate, or of more than 1.5 per cent, ufquiuidiue
sulphate.
CINCHONINA.
CTNCHONINUM.
CineAaiiine. Oinehania.
Oer. CincUoiiin ; Fr. Cincliranine; 8p. Cinconina.
C„H„N,0; 294.
Colorless, transparent, monoclinic prisms or needles, without
odor, and at first nearly tasteless, but developing a bitter after
316
MANUAL OF CHBMK
taste, and possessing an alkaline reaction. Tliey contain no T
of crvstallizalton, and are permanent in the air. When heated
to 220° C. (428° F.) they begin to volatilize, and when heated in
a current of hydrogen or ammonia gas, they may be sublimed,
without decomposition, in long needles; they melt at about 250=
C. (482° F.). but assume a brown color, and become thereby par-
tially decomposed; when more strongly heated, upon plalinum-
foil, they become charred, and are tinaily completely dissipated.
Cinchonine ia very sparingly soluble in cold water, one part
requiring at 17° C. (62.6° F.) 3700 parts for solution, and is not
much more soluble in aoluiions of the alkalies or in boiling water,
requiring of the latter about 2500 parts for solution ; it is soluble
in UO parts of alcohol at 15° C. (59'' F.). in 28 parte oF boiling
alcohol, in 370 parts of ether, and in 360 parts of chloroform, fi
diasolves readily in dilute mineral acids, with the formation of
neutral or acid salte, which are mostly well crystal] izable, and
possess a persistent, strongly bitter taste.
In contact with concentrated nitric or sulphuric acid, cinchonine
suflera no change of color (distinction from brucine. morpbine,
salicin, etc.), and its solution in the latter acid does not anbrd a
purple coloration in contact with a crystal of potassium bichro-
mate (distinction from strychnine).
The aqueous solution of cinchonine possesses an alkaline reac-
tion and a bitter taste. When cinchonine is dissolved in water,
acidulated with dilute sulphuric acid, the solution displays no fluo-
rescence, and, upon the addition of a little chlorine- water, and sub-
sequently of ammonia, no green coloration is produced (distinction
from quinine and quiuidine). It ia distinguished from cincho-
Tiidine by the solubility of the latter in 76 parts of ether, whereas
cinchonine, as stated above, requires 370 parts for solution.
Ill the absence of any specially characteristic chemical test for
cinchonine, its identity may be determined, in connection with
the above described physical characters, by its property, common
to all cinchona alkaloitls, of aftbrding, when mixed with a little
sugar, and heated in a perfectly dry test-tube, a bright-red tarry
sublimate, which, an far as at present known, is only produced
by the dry distillation of cinchona barks, or the alkaloids contained
therein, when in contact with some indifferent organic substance,
such as the above-mentioned carbohydrate.
When cinchonine is dissolved in water, acidulated with dilute
sulphuric acid, it responds to the teats for a solution of cinchomne
sulphate, as described under the latter, on page 317.
k
This hooh is the proi
COOPER MEDICAL CO' ..... .^
8AN fflANCISCO. CAo
onrf if nof h< >■>> V'"- ■ 'i '' 'H the
£4bmri/ /. •■ I ' ' "" or
under li ■ I
CINCHORIKA. 317
CIXCHO!nNUM 8EU CINCHONIUM 8ULFUR1CUM.
Sulphaie of Cinehonine or Cinehonia. Cinchonine Sulphate.
Ger. Schwefebaiires Cinchonin ; Fr. Sal fate de cinchonine ; Sp. Sulfato de
ciDOoninm.
(C„H„N,0),.H^,+ 2H,0 : 722.
Transparent and colorless, hard, shining prisms of the mono-
clinic system, possessing no odor, but a very bitter taste, and a
slightly alkaline reaction. They contain two molecules (4 98 per
cent.) of water of crystallization, which are lost bv drying at
100^ C. (212^ F.). When heated to about 240° C. (464° F.), the
salt melts with partial sublimation, and when strongly heated,
upon platinum foil, it fuses to a red, resinoid mass, becomes
charred, and is finally completely dissipated.
Cinchonine sulphate is soluble in about 70 parts of water and
in 6 parts of alcohol at 15° C. (59° F.), in 14 parts of boiling
water, in 1.5 parts of boiling alcohol, and in about 60 parts of
chloroform, but is insoluble in ether or benzol ; it dissolves rejidil v
in dilute sulphuric acid, with the formaition of an acid sulphate,
or mono-cinchonine sulphate, C,gH,jNjO.HjS0^4-4HjO, which is
difficultly crystallizable, and soluble in half its weight of water,
but requires 100 parts of absolute alcohol for solution.
The aqueous solution of cinchonine sulphate possesses a very
bitter taste, and exhibits no fluorescence ; it is precipitated by
the general alkaloidal reagents: potassio-mercuric iodide, platinic
chloride, tannic acid, etc., and upon the addition of solutions of
the alkaline hydrates, carbonates, or bicarbonates, a white pre-
cipitate of cinchonine is produced, which is but very 8}>aringly
soluble in an excess of the precipitant ; with potassium ferro-
cyanide a white amorphous precipitate is produced, which, upon
warming, is soluble in an excess of the reagent, and is separated
in a crystalline form upon cooling; with solution of barium
chloride it yields a white precipitate of barium sulphate, insoluble
in hydrochloric acid.
In contact with concentrated nitric or sulphuric acid, cincho-
nine sulphate sufters no change of color (distinction from brucine,
morphine, salicin, etc.), and its solution in the latter acid does not
aftbrd a purple coloration in contact with a crystal of potassium
bichromate (distinction from strychnine).
Cinchonine sulphate is distinguished from the sulphates of qui-
nine and quinidine, by its greater solul>ility in water, by the
absence of any fluorescence of its solution in dilute sulphuric
acid, and by the latter solution, upcm the addition of a little
chlorine- water and subsequently of ammonia, affording no green
coloration ; it is also distinguished therefrom by the very sparing
318
MANUAL OF CIlEMCCAt ANALYSIS.
solubility of the pure alkaloid, wbcn precipitated from a solntiOQ
of its salt by ammonia- water, and subsequently fhaken with ether.
It is distinguished from cinchonidine sulphate by the, latter requir-
ing 1000 parts of chloroform for solution, whereas anhydrous
cinchonine sulphate is soluble in 60 parts of chloroforra ; and, ou
the other hand, free cinchonidine is soluble in 76 parts of ether,
whereas pure cinchonine requires 370 parts of ether for solution.
r
Codeint. Codtta.
Oct. Codein ; Fr. Codeine ; Sp. Codeiaa.
C„H„NO, + H,0; 317.
Colorless, transparent, octahedral crystals, belonging to the
rhombic system, and containing one molecule {o.6S per cent.) of
water of crystalJization, which is lost by drying at 120° C. (248° F.).
When crystallized from aghydrous ether or carbon bisulphide, il
forms small, colorless crystals, containing no water of crystalliza-
tion, but likewise belonging to the rhombic system.
Codeine, when previously deprived of its water of crystalliza-
tion, melts at 150° C. (302° F.), and solidifies upon cooling in a
crystalline form; when strongly heated upon platinum foil, it is
decomposed with the evolution of inflammable vajiors, and is
finally completely dissipated. It is soluble in 80 parts of water
at 16^ C. (oH" F.), and in 17 parts of boiling waier, in 6 parte of
ether, iu 10 parts of benzol, and freely soluble in alcohol, amylio
alcohol, chloroform, and carbon bisulphide, but very sparingly
soluble in petroleum benzin; when heated with less water than is
required for solution, or when dropped into boiling water, it sinks
to the bottom, and melts in the form of an oily liquid. It is also
readily soluble in dilute acids, with the formation of well cryatal-
lizable salts, which are soluble in water and alcohol, but nearly
insoluble in ether, and possess a strongly bitter taste.
The aqueous solution of codeine has a very bitter taste and
strongly alkaline reaction, precipitating from neutral solutions of
the salts of lead, iron, copper, cobalt, and nickel, their respective
hydrates; and is itself precipitated by the ordinary alkaloidal
reagents: potassio-mercuric iodide, iodinized potassium iodide,
tannic acid, platinic chloride, etc., as also from its saturated solu-
tion by concentrated solutions of putitssium or sodium hydrate,
but remains unchanged upon the addition of ammonia- water, in
which liquid it is nearly as soluble as in pure water.
When a cold salurated aqueous solution of codeine is oare-
L
CODEIWA. 819
fully neutralized wiili dilute sulpljuric acid, it affords no colora-
tion with a neutral solution of ferric cbloride, and does not reduce
iodine from a solntion of iodic acid (distinction Ironi morphine);
neillier does it afford any coloration, or but a alight brownish
one, upon the gradual addition of concentrated sulphuric acid,
and subsequent addition of a trace of potassium bichromate (dis-
tinction from strychnine).
Nitric acid, of the spec. grav. 1.200, dissolves codeine with a
yellow color, without becoming red (additional evidence of the
absence of morphine). With concentrated sulphuric acid it forms
a colorless solution, which, upon ■warming, assumes a green or
bluish coloration, and, after being allowed to cool, yields, upon the
addition of a drop of nitric acid, a blood-red color. With concen-
trated sulphuric acid, containing a trace of ferric oxide in solution,
it affords a deep blue color, which, upon warming, changes to violet
or red. When dissolved in concentrated sulphuric acid, and one
or two drops of a concentrated solution of cane-sugar are added,
and gently warmed, a fine }iurpliBh-red coloration is produced.
With concentrated sulphuric acid, coniainine a little ammonium
mnlvbdale, it aftbrda a green solution, soon clianging lo blue, and
gradually becoming yeilow. It dissolves in chlorine- water, form-
ing a colorless solution, which, upon the addition of ammonia,
becomes yellowish- red.
When equal parts of codeine and iodine are dissolved separately
ID the smallest possible quantity of alcohol, and the solutions
mixed, small, deep violet-colored crystals of codeine tri-iodide,
CnHj.NOj.Ij, are separated upon standing; they possess an almost
metallic lustre, are insoluble in water and ether, out dissolve with
a reddish-brown color in alcohol.
When heated with concentrated hydrochloric acid, in a sealed
tube, codeine is resolved into methyl cbloride and ujwmoryi/ttwe
hydrochiorate:
C„H„N03 + 2HC'l = H,0 -|- CII,C1 + C,JI„NO,.nCl.
li}'drocliliiTal«,
readily
Codeine.
Apnninrpliti
With glacial acetic acid or acetic anhydride, codei
converted into acei/ll-codeine :
C„H„NO, + C,II,0, .
Codlne.
n,o + c,.n„(c,n,o)No,.
Auulyl-cmleitie.
Codeine hydrochlorali', when heated for a short time at 180 ~ C.
(856° F.) with a conconirated solution of zinc chloride, is con-
verted into apoco'/eine hydrochioratK :
C„H„NO,.HCl - H,0 -I- c,.n„NO,.nc].
Codeine liydrocblorsle.
ApiiciKklae lijilrochloml
320
, OF CBBMICAL ANALYSIS.
Codeine in ila composition and cliemical charnotera
regLirded aa methyl-morphine, C„II„(Cn,)NO,. It in distin-
giiished from morphine by its ready solubility in ether and chlo-
roform, and greater solubility in water, as also by sll'ording no
precipitate with solution of mercuric chloride, by not reducing
iodine from a solution of iodic acid, and other special tests; it is
distinguished from narcotine in not being precipitated by ammo-
niawater from an aqueous solution of its salts, and by not being
absorbed by chloroform from an acid solution of its salts, as also
by the special chemical tests and reactions.
The shove described characteristics of codeine are sufficient to
ascertain ita identity and purity. Fraudulent admixtures, like
sugar-cryatals, or crystallized inorganic, salts, are at once indicated
by their ready solubility in cold water, and by their insolubility
in alcohol and ether, and the latter also by a fixed residue upon
incineration on platinum- foil.
For the separation of codeine from other alkaloids, or wlieo
associated witn complex organic mixtures, see page 108.
COLCHICINA.
COLCHICISUM.
L
Gor. Coltbicin ; Fr. Cokliicine ; Sp, Colchicina.
C„H„NO.; 337.
An amorphous, yellow, or yellowish white mass or powder,
possessing a feebly aromatic odor, a very slight alkaline reaction,
and a persistent, strongly hitter tasle. It melts at li5° C. (_298**
F.), acquiring thereby a bmwn color, and solidifies on cooling, lo
a transparent brittle mass; when heated upon platinum-foil, it
lueltB and burns away, with inlumefcence, leaving no residue, or
but slight traces of ash.
Colchicine is freely soluble in water, alcohol, and chloroform,
but very sparingly soluble in ether. Its aqueous s-jlulion has a
bright yellow color, which becomes more intense upon the addi-
tion of alkalies or mineral acids, and a very bitter, but not an
acrid taste; it is nrecipiialed by tannic acid, phospho-molybdic
auid, and iodinizeu potasaium iodide, and assumes with ferric
chloride a dark preen coloration; but witli pot assio- mercuric
iodide, polassio-cadmic i<xlide, and picric acid, no precipitate
or but a faint lurbiditv is produced, until after the addition of a
mineral acid; with chlorine- water, a yellow precipitate is pro-
duced, which dissolves in ammonia-water with an orange-yeilow
color.
COLOHICINDM. 321
Colchicine, when added to concentrated sulphuric acid, in a dry
test-tube, agglomerates, and, upon agitation, dissolves with an
intense yellow color; upon the subsequent addition of a drop of
nitric acid, a dark-brown zone is produced, which gradually changes
to violet, and becomes finally yellow; the reaction being more
distinct and the violet coloration more permanent when, instead
of nitric acid, a little potassium nitrate is employed.
When brought in contact with a few drops* of very concen-
trated nitric acid, in a small porcelain capsule, a violet or bluish-
violet coloration is produced, which soon changes to a brownish-red;
upon the subsequent addition of a little water, a bright yellow
solution is obtained, which, upon supersaturation with an alkali,
assumes a fine orange-yellow or orange-red color. With mod-
erately concentrated nitric acid, colchicine produces simply a
yellow coloration, but if a little concentrated sulphuric acid be
subsequently carefully added, a transitory, but pure violet colora-
tion will be produced at the point of contact of the two liquids.
Colchicine, by long-continued exposure to the air, or upon
warming, is converted, through the loss of water and ammonia,
into an amorphous, dark-brown, resinous body, very sparingly
soluble in water, colchicoresin, C^jIIg^NjO,,.
3(C^H.£f O.) - C..H„y,0.. + NH, + 311,0.
Colchicine. Colcliicoresin.
By the action of dilute mineral acids in the cold, or more
quickly upon heating, colchicine is converted into crystallizablo
co/cAtcem<?, associated with small and varying amounts of an amor-
phous, dark-brown, resinous product, insoluble in water and
ether, heta-cohhicoresin^ Cj^HjgNOjj,.
C,,n„NO, - C„H„XO^-f H,0.
Colchicine. Colchiceine.
Colchiceine, C,^Hj,NO, 4- 2HjO, crystallizes in small, colorless,
rhombic tables or prisms, which melt at 150° C. (302° F.), and
solidrfy upon cooling to an amorphous, yellow, brittle mass; it
possesses a taste less bitter than that of colchicine, and a slightly
acid reaction.
Colchiceine is sparingly soluble in cold, more readily in hot,
water, and freely soluble in alcohol, chloroform, and solutions of
the alkalies, but is difficultly soluble in ether; its alcoholic solu-
tion deviates the plane of polarization to the left, and possesses a
slight acid reaction. When heated for some time with water, at
a temperature of 100° C. (212° F.), it is converted into a yel-
lowish-brown, uncry stall izable mass, and is apparently thereby
inversely converted into colchicine. Its aqueous solution assumes
a yellow color upon the addition of mineral ac ds, and, upon
boiling therewith, is decomposed, with the separation of a brown-^
21
CT2 MANUAL OP CHEMICAL ANALYSTS.
iah resin ; it is not prec'pilated by tannic acid, except upon s
ing. and aftbrdB no precipitate with potassio- mercuric iodide or
picric acid, even upon llie addition of an acid, but, like colchicine,
RtiBumes R brigiil green color upon the addition oC a dilute solution
of ferric chloride,
Colcliiceine combines with bases to form salts, which are amor-
phous, and, with the exception of the potass. um and sod.uni
compounds, insoluble in water, liut readily soluble in alcohol and
chloroform.
Colfhioine is a very indifferent substance, being capable of com-
bining with proportionately few, and apparently with no ac d
Imdies, to form a definite chemical compound, and possesses but
few properties which are common to the group of organic bases.
It is proiiiinently distinguished from most alkaloids by being Ab-
sorbed from its ac'd solutions by ether, chloroform, and amylic
alcohol, and may thus be readily separated from tbem, or from
other complex organic principles with wli ch it may be associated,
as dcscr.bed on page 106.
CONIINA.
Coniine. Oonin.
Ger, Conllo ; Fr. Conicine ; 9.\\. Contcinft.
C,H„N - C,H,.=NH ; 125.
A colorless, transparent, oily-looking, volatile fluid, becoming
browu and darker upon exposure to warmth and uir; it has n
strong, penetrating odor, resembling that of a combination of the
odors of tobacco and mice ; its tasie is acrid, somewhat like that
of oil of tobacco, and it is exceedingly poisonous. When dropi)«d
upon paper, coniine produces, like an essential oil, only a transient
stain, which by a geutle warmth entirely disappears. Ii burns
with a bright, smoky flame, and, when healed upon platinum -foil,
is entirely dissipated.
The spec. grav. of coniine is 0,846 at 12.5" C. (54.50 F.); when
drtipped upon water, it floats (distinction from nicotine). In an
atmosphere free from oxygen, it boils at 170-' C. (338° F,) with-
out decomposition,
Coniine combines at 2" C. (35.()° F.) with one-fifth of its
weight of water, forming a clear solution, wliich, however, bo
comes turbid by elevation of tomi»eralure, and assumes a cloudy
appearance when a glass vessel containing it is heated by the
warmth of the hand (additional distinction from nicotine). It
is but sparingly soluble in water, one part requiring at 17° C.
^ F.) 100 parts of water for solution ; the saturated at^utiua
CONIINA. * 823
has a strongly alkaline reaction, becomes turbid when warmed,
turns brown when exposed to the air, and gradually deposits a
brown resinous mass; it forms precipitates with tannic acid,
potassio-mercuric iodide, iodinized potassium iodide, mercuric
chloride, and picric acid, as also with chlorine, bromine, and
iodine-water, but not with platinic chloride. •
Coniine di8St)lves readily in water acidulated with hydrochloric
acid, and is miscible with alcohol, amylic alcohol, ether, and aceton,
as also with the fixed and volatile oils, but is sparingly soluble in
chloroform and petroleum benzin ; it decomposes carbon bisul-
phide, particularly upon warming, the solution assuming a yellow
color, with the separation of sulphur.
When coniine is carefully neutralized with hydrochloric acid,
and the resulting salt dissolved in alcohol, it affords upon the
addition of platinic chloride a precipitate of the double salt
(C,H„N.HCl),PiCI^, which is very freely soluble in water, but
may be crystallized from alcohol.
Coniine readily dissolves sulphur, with the formation of a red-
dish-yellow liquid, as also argentic oxide and chloride, *and
resembles ammonia in its behavior towards solutions of the salts
of aluminium and the heavy metals; it precipitates the hydrates
or oxides from solutions of the salts of aluminium, tin, mercury,
copper, silver, lead, zinc, iron, and manganese, but the precipitate
produced in solutions of cupric salts is insoluble in an excess of
coniine (distinction from ammonia).
Coniine neutralizes diluted acids completely with the formation
of neutral salts, which are mostly difficultly cry stall izable and
deliquescent, readily soluble in water, alcohol, and in a mixture
of ether and alcohol, but not in pure ether. Although odorless
in their dry condition, the aqueous solutions of salts of coniine
are very prone to decomposition, soon becoming discolored, even
at ordinary temi)erature8, and evolving the odor of coniine.
Coniine produces white fumes with the vapors of nitric, hydro-
chloric, and acetic acids, and is rapidly decomposed in contact
with tlie concentrated mineral acids. With concentrated sul-
phuric acid, it assumes a purplish-red color, which gradually
changes to olive-green. With a very small amount of concen-
trated nitric acid, a blood-red coloration is produced; upon the
addition of large amounts of the acid, a violent reaction ensues,
with the evolution of nitrous acid vapors. In contact with dry
chromic anhydride, coniine becomes instantly inflamed.
When coniine, dissolved in a little ether, is allowed to evapo-
rate in a small porcelain capsule, by swaying it to and fro, and
the residue, distributed over the interior surface of the capsule, is
brought in contact with dry hydrochloric acid gas, a purplish-red,
and finally an indigo-blue coloration is produced.
The alkaline hydrates do not act upon coniine, with the excep-
tion of decreasing its solubility in water.
NUAL OF CHEMIC
ANALYSTS.
Examination ;
An admixture uf volah'lc or fixed oils, or of ammonia (wliich
may ali'o liave resulled from the gradual decomposition of the
eoniiue), may be detected by mixing one drop of ooniioe with 10
drops of water, upon a walcb-glasa or in a test-tube, and by the
Bul^equent addition of one drop of strong hydrochloric acid ; the
eoniine should readily and wholly dissolve lo a clear homogeneous
liquid ; any turbidity or oily appearance would indicate such an
admixture. If, now, a few dropB of a soliition of platinic chloride
are added, a yellow crystalline precipitate will be produced if
ammonia is present. The presence of ammonia may also be de-
tected by mixing 2 parls of eoniine with 1 part of water, and
Bubscqucntly carefuUly neutralizing the mixture with oxalic acid ;
after standing for some hours, crystiils of atnmoniuni oxalate will
separate from the colution if ammonia be present, and the filtrate
will afford an additional amount of the salt upon the addition uf
a mixture of one part of ether and three parts of alcohol ; pure
eoniine oxalate is soluble in the latter liquid as also in strong
alcoliol,
Niaitine will be indicated by a higher specific gravity (1.027
at 15'" C =■ o9° F.), as also by ils property of mixing with water
in all proportions, forming clear solutions, which do not become
lurbid upon warming, nor upon the addition of chlorine-water, or
ill contact with bromine vapor, but aflord a crvstalline precipitate
upon the addition of a solution of platinic chloride.
The separation of eoniine from many other alkaloids or from
complex organic matters, may be eft'ected by its property of being
absorbed by ether from an alkaline solution, as described on pago
108; and may usually be readily recognized by its characteristic
odor, and the above- described physical and chemical properties.
It should, however, in toxicologieal research, be carefully identi-
fied as distinct from the class of bi>dies called ploviames or septi-
cine, which are produced by the spotitaneous deeompoMlion of
animal matter, and which have received brief notice on pages
104 and 105.
CREABOTDM.
CREUSO'rrM. KREOSOTLM.
CTtntote, Wood-Tar CreaieU.
QeT. Kreoaot ; Pr. Cr£osole ; 8p. CreototA.
A distinction has to be made with commercial creasoie between
the creasote obtained from wood-tar and thai derived froni coal-
tar; the latter is principally a mixture of impure phenol, creaol,
CRBA80TUM. 825
and similar homologous phenols, or only an impure carbolic
acid, and exhibits the properties and reactions of carbolic acid
{see page 139), whereas wood-tar creasote, although not a sub-
stance of definite or constant composition, contains as its essen-
tial constituents, cresoJ, CrtH/CH3)0H, in its different isomeric
modifications, phlorol, CgH,(CH,)^OH or CrtH^(CjH3)0H, (/uaiacol
C.H,(OCH,)OH, and creosol, C,H,(OCH3)(CH3)On.
Wood tar creasote is a colorless or pale yellow, transparent,
somewhat oily and strongly refractive liquid, of a peculiar, per-
sistent odor, resembling that of smoked meat, and of a caustic,
pungent taste; it is neutral in its action upon litmus, and does
not decompose by exposure to the air and light, but absorbs
moisture, and becomes in time yellowish or reddish. It is com-
bustible, and burns with a sooty flame.
The specific gravity of wood-tar creasote is 1.035 to 1.085 at
12° C. (53.6° F.), and its boiling-point at about 203° 0.(397.4^ F.),
but it does not crystallize, nor solidify, when its temperature is
reduced to — 27° C. = — 16.6° F. (distinction from coal-tar crea-
sote).
Wood tar creasote is but sparingly soluble in water ; when
mixed with from 120 to 150 parts of hot water, it affords a clear
solution, which, however, becomes turbid on cooling, and grad-
ually, after the separation of the excess of creasote, again clear.
It is miscible with absolute alcohol, ether, chloroform, benzol,
glacial acetic acid, carbon bisulphide, and with fixed and volatile
oils, and some varieties form a clear mixture with anhydrous
glycerin, while others do not. It is also readily soluble in mod-
erately concentrated or strong solutions of potassium or sodium
hydrate, but sparingly soluble in ammonia-water; when mixed
with a little ether, it affords, upon the addition of a concentrated alco-
holic solution of potassium hydrate, a crvstallizable compound of
potassium creosolate, KC,H^O,-f H,0 (C jl3(OCn,)Cn30K + H,0),
which is soluble in water; it is decomposed by heating with
an alcoholic solution of potassium or sodium hydrate, as also by
contact with cold, concentrated sulphuric or nitric acid.
Wood-tar creasote dissolves phosphorus, sulphur, many resins,
camphor, and fats; it does not coaguKtj albumen nor collodion
(distinction from carbolic acid), and is a powerful antiseptic and
antiputrescent.
A freshly prepared, clear, aqueous solution of wood-tar crea-
sote assumes, upon the addition of a droj) of a dilute solution of
ferric chloride, a bright blue color, which, however, in distinction
to the coloration produced by carbolic acid, changes immediately
to gray, and, upon the addition of alcohol, to green.
Examination :
Carbolic acid, or coal-tar creasote, in their physical properties
and behavior towards reagents, have many similarities with
wood-tar creasote, so that they in ly be either mistaken for, or
326 MANUAL OF CHEMICAL ANALYSIS.
employed as an adulterant of, ihe latter. The two classes of bodiei
may be very readily distingaishetl when in their pure condition,
but the reverse is the ease when the one is mixed or oontami-
nated with the other, whereby the chanicteriatic rosctioiis of eftcb
are more or less concealed. The examination of wood-tar crea-
sole for its purity, and for the determination of the abaence of
any considerable proportion of carbolic acid, or coal-tar ereasote,
may, however, be directed to the following tests. Wood-tar orea-
fiote should require not less than 120 i>arts of cold water for solu-
tion, and should boil at a temperature not below 200* C, (392°
F.). It should not dissolve when shaken with tivc limes its
weight of stronger ammonia-water.
When one part of wood-tar ereasote, and one part of stronger
ammonia- water, are heated with one thousand parts of water, the
solution, after cooling, should afford, in conuicl with the vapor of
bromine, and subsequent agitation, do blue coloration, even after
standing for several hours. This teat will serve to detect tlie
{)resenco of carbolic acid in wood-tar ereasote, in amounts of not
ess than 2,5 per cent.
The following diatinctiona between the two bodies may be also
observed :
Wood-tar creasole remains liquid when cooled in a mixture of
broken ice and e"mmon salt; coal-tar ereasote and carbolic a(»<I
either solidify or deposit crystals at auoh temperatures.
Wood-tar ereasote, when mixed and shaken with collodion,
produces a clear liquid; carbolic acid and coal-tar ereasote form
a kind of jelly.
The admixture of ooltilUe or fixed o!ts and oily impKrilira may
be detected when one part of the ereasote is agitated wiili three
parts of strong acetic acid; a clear solution must take place; a
residual oily layer or oily appearance would indicate such admix-
lures.
CUFRI ACBTAB.
CUPRUM ACETICUM.
Aetlaie of Copper. Ouprie Aeetait.
; 8p. Acelato d«
Cu{C,Hpj,-|-H,0; 199.2.
Peep green, prismatic crystals, belonging to the mouocUnic
system (Fig. 112). having a specific gravity of 1.914, and sligbtlv
efflorescent on exposure to tlie air. They contain one molecufe
(fl.03 per cent.) of water of crvslallization, which, togetlier with
traces of acetic acid, ia lost by drying at 140° C. (28*** F.) ; at 2-U>
Fio. 112.
CUPBOM. 327
to 260° C. (4(>4 to 500° F.) acetic acid and aceton arc evolved,
and at 270'* C. (518^ F.) white, woolly flakes of cuprous a
Ca^CjIIjO,),, begin to sublime, together with
the evolution of carbonic acid and inflammable
gaaes, whilst a residue, consisting, for the most
pari, of metallic copper and its oxides, re-
mains. When strongly heated upon platinum
foil, the crystals glimmer with a greenish-
colored flame, and when tritnrated, or gently
warmed in a tesitube, with concentrated
sulphuric acid, the odor of acetic acid is
evolved.
Cupric acetate is soluble in 15 parts of
water and in 135 parts of alcohol at 15° C.
(59° ¥.), in 5 parts of boiling water, aud in
14 parts of boiling alcohol, spec grav. 0.880,
but is insoluble in ether; its solutions have
a bluish-green color, a nauseous, styptic taste,
and assume, when much diluted with water, an azure-blue color
upon the addition of an excess of ammonia-water or solution of
ammonium carbonate, the cold solution remaining clear upon the
subsequent addition of a solution of potassium hydrate, but, upon
heating therewith, the entire amount of copper ia precipitated aa
black, hydrated cupric oxide.
When cupric acetate is dissolved to saturation in dilute acetic
acid, at 60° C. (140" F.), the cold solution affords large prismatip
crystals of a salt having the composition Cu(C,H,0,),+5HjO; at
30° C. (8(3° F.) this salt is resolved into a crystalline powder ol
the ordinary acetate, with the elimination of water.
Ilxaininauon ;
AlkalifS and alkalme earths may be detected by completelv pre-
cipitating the aqueous solution of cupric acetate, acidulated with
hydrochloric acid, by hydrogen sulphide; the filtrate should leave
no residue upon evaporation, and should yield no precipitate upon
the addition of a solution of sodium carbonate in excess; in the
latter instance confirming also the absence of alitmininm, zinc,
and iron.
Metallic impurities may be detected by completely precipitating
a boiling aqueous n^^lution of the Rait with potassium or sodium
hydrate; the flltrate should afford no coloration or precipitate
when saturated with hydrogen sulphide; a dark coloration or
precipitate would indicate lead, a white precipitate, zi»c.
Carbonic, sulphuric, and hydrocltloric acids may be detected by
dissolving a little of the salt in dilute nitric acid; effervescence
will indicate carbonates; the clear solution is then tested in sepa-
rate portions, with barium chloride for snlphnric acid, and with
nreentic I'itrate for hydrochloric acid ; a while precipitate in
either case will reveal the presence of such impurities.
B28 MANUAL OF OlIEMtCAL ANALYSIS.
Ars'-nic, the presence of wliich may be due to an accidental ad-
mixture with Schtcnn/urlh r/reen (a mixture of ciiiiric acetate
with arsenite), or Sclieel^'s t/reen (cupric araenite), may be detected
by dissolving a little of the salt in diluted sulphuric acid, and
testing in March's apparatus, aa described on page 33 ; or, by the
repeated evaporation of the cupric acetate to dryness willi ammo-
nia-water, and finally extracting the residue witli hot water, as
long m it thereby aftbrds a colorless liquid upon filtratioli ; thp
filtered sohitiitn, "which will then contain the arsenic, if present,
in the form of araenic acid, will respond to the well-known tests
of the latter.
Cupri Sab&oetaB.^ Aeriiffo or veriii'jns is a mixture of several
basic cupric acetates with various impurities; it occurs in masses
of a pale-green or bluish color, or in bluish crystalline scales or
needles, which, upon gently heating, or by exposure to the air,
assume, in consequence of tne loss of water, a green color. When
heated upon charcoal before the blowpipe, it becomes decom-
posed, with the evolution of inflammable vapors, leaving a residue
of metallic copper. When heated in a test-tube, with concen-
trated sulphuric acid, it emits acetic-acid vapors. Water resolves
vertligris into a more freely soluble, less basic acetate, and an in-
soluble, more strongly bapic salt; the decomposition takes place
more quickly upon gently warming, and may be represented
essentially by the following equation :
3[Cu(C,H,0^,-t-Cu(On),3 = [Cu(C,H,0,).^-Cll(OH•|,^-V-
[Cu(C,njO,),.f 2Cu(on),].
Verdigris is soluble in diluted acetic, hydrnchloric, nitric, and
sulphuric acids, and in an excess of ammonia-water or solution of
ammonium cnrbonate; the insoluble residue cnnsista mainly of
impurities, among which calcium carbonate (crude chalk) is rec-
ognized by effervescence of the verdigris with acids. For further
examination, its solution in diluted hydrochloric acid is com-
pletely precipitated by hydrogen sulphide; the filtrate should
_ leave no residue uimn evaporation, nor attbrd a precipitate when
L BUfier-satu rated witli sodilim carbonate; a re-tidue and a brown
■ precipitate would indicate alkaline salts or earlhy a<lmixlures, or
This hooh is the p.
OOpPER MEDICAL ( -
SAN fRANCISCO, C'
Wtdi." iwf t- !■■ r
labTti ■ 'I :
U-ndi-.y .^
CUPRVM. 329
CUPRI OXIDUM.
CUPRUM OXYDATUM.
Black Oxide of Copper. Guprie Oxide.
Ger. Knpferoxyd ; Fr. Bioxyde de cuivre ; Sp. Ozido de cobre.
CuO; 79.2.
A dense, black powder, when prepared by the ignition of cupric
nitrate; or a less dense, bluish-black, soft powder, when obtained
by the ignition of cupric carbonate or by precipitation. It re-
mains unaltered when heated to redness, is insoluble in water and
alcohol, but slightly soluble in saliva and in the gastric juice, and
readily soluble in acids ; its solutions have a blue or greenish-blue
color, and they assume, when so much diluted as to appear almost
colorless, an azure-blue color upon the addition of ammonia- water,
and a brownish-red color with potassium ferrocyanide.
When heated upon charcoal, before the blow-pipe, cupric oxide
is readily reduced to metallic copper. It has a strong affinity for
moisture, and should therefore be preserved in tightly closed
vessels.
Cupric oxide, when prepared by precipitation, is readily and
completely soluble in a warm solution of ammonium chloride
(distinction from ferric oxide).
Examination :
Cupric nitrate is recognized, in the oxide, by the evolution of
acid nitrous vapors, when heated, in a test-tube, either dry, or
with concentrated sulphuric acid ; if they are not distinctly rec-
ognized by the odor, they are by their action upon moist blue
litmus-paper, when held in the orifice of the tube.
Metallic Impurities. — A portion of the oxide is dissolved in
warm concentrated hydrochloric acid, the solution diluted with
water, and the copper completely precipitated by hydrogen sul-
phide ; the liquid, rapidly filtered from the precipitate of cupric
sulphide, should leave no residue upon evaporation, and yield
no precipitate upon supersaturation with sodium carbonate; an
ensuing precipitate would indicate metallic (ferric) or earthy
oxides.
Carbonic^ hydrochloric^ and sulphuric acids may be detected by
dissolving a little of the cupric oxide in nitric acid ; eflervescenee
will indicate carbonates ; the clear solution is then diluted with
water, and tested in separate portions, with barium chloride for
sulphuric acid, and with argentic nitrate for hydrochloric acid ;
an ensuing white precipitate in either case will reveal the presence
of such impurities.
AL OP CHEMICAL ASALV8IS.
CUPRI SULPHAS.
CUPRUM SULFURICUM.
SHlphiiU nf Cojipar. Cuprk Salphalt. Bltu Vitriol.
Get. StliwerGlsDUrei Kapreroxyd : Fr. E'UlfnlcdecuiTro ; Sp. SulfHIodccolirc.
CuSO^-l-6H.O; 249.2.
Larpe, transparent crystals, of a deep blue color, belonging lo
the iriulinic system (Fiy. 113), ami having a apccifio gravity of
2.277. Tbey contain five mnU-cuIcs
Fio. 118. (3U.08 per cent.) of water of cryftLullixa-
^^^^^^ tion, effloreBce slightly upon the surfaoc
'^^^0^^^^^ ^y expii9ure to a very dry atmosphere,
^^^^ I and lose fiiiir inoleiniles (28.S ]icr cent.)
^M I of warer when heated for some lime to
^^H ■ 100' C. (212" F.). leaving a salt of the
^^_ ^^^M ^^^^M (■ompd^tiou CnSO, 4- H^, in the form
^^^^^Li^^^^^^^^^^^^^ of H bill sh-white powder; atatemper-
^^^^^n^^^^^^^^^^ 4ii4° F.) the remaining molecule of
^^^^^^^^ water ie eliminated, and at a whit«
^^^^^ hent the salt is decwmpoaed, with the
cvoUition of sulphur tnoxide, sulphur
dioxide, and oxygen, leaving a residue of black cupric oxide.
The anhydrous salt is colorless, but absorbs moisture with groat
avidity, assuming again a blue color.
Cupric sulphate is soluble in 2.6 parts of water at 15* C, (59"
F.), and in 0.55 part of boiling water, but is insoluble in absolute
alcohol and ether, and very sparingly soluble in dilute alcohol.
Its solution hafl an acid reaction, a strong metallic, styptic taste,
and, when diluted with so much water as to make it appear
almost colorless, reassumes a blue color upon the addition of am-
monia-water; it gives a white preuipitate with barium chloride, a
reddish-brown one with potassium fcrrocyanide, and a green one
with arsonious and arsenic acids u|ion subaeiiuent exact neutrali-
sation of the liquid with ammonia- water.
Examinatioa :
Ferrous sulphate is recognized by dissolving the sulphate is
diluted ammonia-water, or, in solutions, by adding an excess of
ammonia-water ; the ferrous hydrate is precipitated together with
the cupric hydrate, without, however, being redissolved by an
excess of the reagent.
Traces of iron may be detected by mixing an aqiicoujt solution
of the salt with twice its volume of chlorine-water, and by the
subsequent addition of ammonia- water; the precipitate, formed
by the first addition of the ammonia-water, will be diasolved by
a sufticient addition of the reagent, yielding a complete violet-
CUPRUM. R81
blue solution. This is then filtered, and, when all the liquid has
passed through the filter, the latter is washe<l with a little dilute
ammonia- water; a brown coating, remaining upon the filter,
would indicate traces of iron salts.
Aluminium, Aftu/nestHm, Zinc, Potassium, and So/linm Sulphates.
—A small portion of the cnpric sulphate, taken from a numhor
of triturated crystals, is dissolved in about ten times its weight
of water, the solution acidulated with hydrochloric acid, and the
copper completely precipitated by hydrogen sulphide; the liquid is
then rapidly filtered from the precipitate of cupric sulphide, and
the filtrate evaporated to dryness, when no residue should remain ;
if a residue in thus obtained, it is dissolved in a little water, the
solution acidulated with a few drops of hydrochloric acid, and
ammonia-water, in considerable excess, subsequently added ; a
white fiocculent precipitate, insoluble in an excesa of ammo-
nia-water, will inaiaale aluminium ; the liquid filtered from the
latter precipitate, if such be obtained, is then tested in separate
portions with ammonium sulphide and with sodium pliosphate;
a white precipitate with the first reagent would indicate zinc, a
white crystalline precipitate with the latter reagent, muijnesivm.
If neither of these be present, the above obtained residue should
be tested for potassium and sodium sulphates, which may he recog-
nized by the violet or bright yellow coloration imparted to the
non-luminous flame.
Estimation of Commeroial Crude Ctiprlo Bnlphate :
The following is a simple and ready method of a.scertainiog the
percentage of cupriu sulphate contained in crude blue vitriol,
some inferior kinds of which arc largely crystallized together
with ferrous sulphate : About ten grams of the salt, taken from
a portion of the mixed and triturated crystals, are dissolved, in a
small tared glass capsule or beaker, in ten tinies.their weight of
water; when necessary, the solution is filtered, and the filter
washed with a small portion of water; the filtrate is returned to
the beaker, is acidulated with about live grams of concentrated
hydrochloric acid, and then a piece of a thin zinc roil, about one
inch long, is suspended in the solu-
tion by a very thin platinum-wire . Fio. 114.
(Fig. 114); the beaker is then al-
lowed to stand perfectly quiet for
twenty-four hours. After that lime,
the copper will have precipitated
as a bright, spongy mass, around
the zinc rod. In order to ascertain
if the precipitation has been com-
plete, a few drops of the solution
are taken by a glass rod or a pipette, and dropped into a little
ammonia- water, or tested with a solution of potassium ferrocya-
aide, or with water saturated with hydrogen sulphide : they will
S32 MANUAL OF ClIBUtOAL ANALYiiie.
produce a blue coloration in the first instance, and a reddiah-brow n
or brown turbidity with the latter reagents, if any copper is left
in solution. The copjjor is then carefully and completely removed
from the zinc rod by means of a camera-hair brush, and, if neces-
sary, the apparatus is allowed, a^er the addition of a little diluted
hyarochloric acid, to stand for twenty-four hours more; then,
when the copper is completely abstracted from the solution, it is
brushed down into the liquid, and washed from the zinc by mi^ans
of a wash bottle; the xinc is now removed, a little diluted hydro-
chloric acid added, and the copper allowed to deposit; when thin
has taken place, the supernatant liquid is carefully removed by
decantation, or by means of a pipette, and water is added nnd
removed in the same manner as soon as the copper has subsided ;
this washing is repeated several times, until the water ceases to
redden litmus-paper, the copper being finally washed with strong
alcohol. Then the beaker with the copper is completely dried ai
a temperature of 100° C. {212° F.), and is finally weighed. The
weight gives the quantity of metallic copper, and, multiplied by
2.542, the corresponding quantity of cryslallized cupric sul-
phate, contained in ten grams, or the amount of the blue vitriol
employed.
Table of the percentage ttrength of toliilioiu of eryttalUzed Citpric
Sulp/iale (CuSd,-|-5H,0) of different ipeeijie t/ravitie*.
Tempenilore 15o C. (flfto p.).
P«Mnt.«t
PWO.BI of
BpmUi
OMrfSH^-
tnxMj.
Co90,-hlH,0.
(n*U,.
CoSOrtJaiO.
n»*Hr.
1.007
g
i.o«a
17
. l.I«
1018
10
I.OflB
18
l.ltt
1.030
11
1,078
18
I-IM-
1.097
13
1.084
1.144
1.038
1»
I Itfll
31
1.040
14
i.on9
n
I.IW
1.048
IS
l.lOfl
S»
I.IW
l.OSS
16
1.114
24
1.17T
p-
CtrPRUM AMHONtA.T17H.
CUPRUM SULFUItlCUM AMMOM.VTUM.
Ammoniattd Copper. Ammonio-Sulpli/ite of Copper. Ammonialed
CuSO, + 4NH, + H,0 ; 245.2.
A deep azure-blue, crvHtaliine powder, or long, thin, tniD8>
parent prisms of the rhombic systein, and possessing an ammo-
CURARINA. 833
niacal (xJor. The crystals, upon exposure to the air, lose ammonia
and water, and are gtadualJy transformed into ammonium sul-
phate and basic cupric salphate; when gently heated to 150^ C.
(302® F.), they are converted into a powder of an apple-green color,
having the composition CuS0^ + 2JfH,.
Ammoniated cupric sulphate is soluble in about two parts ot
cold water, affording a fine blue solution; incomplete solubility
indicates partial decomposition. When the solution is diluted
largely with water, it becomes turbid, and separates basic cupric
sulphate, which, however, is redissolved upon the addition of
ammonia- water or of acids, whilst ammonium sulphate remains in
solution.
The salt may be examined, by determining the loss of weight
occasioned by ignition at a gentle heat, which should amount to
35.1 per cent.; the residue, consisting of cupric sulphate, when
dissolved in water, should respond to the tests of purity for the
latter salt, as described on pages 330-381.
C17RARI1IA.
CURARINUM.
Curarine. Guraria.
Ger. Curarin ; Fr. Curarine ; Sp. Curarina.
C3,H„N; 481?
Colorless, four-sided prisms, which are very hygroscopic, and
possess a slightly alkaline reaction, and an intensely bitter taste.
When gently heated they are decomposed, with the evolution of
ammoniacal vapors, and when strongly heated, on platinum- foil,
they are completely dissipated.
Curarine is soluble in all proportions in alcohol and water,
sparingly soluble in amylic alcohol and chloroform, and quite
insoluble in anhydrous ether, benzol, and carbon bisulphide. It
neutralizes acids with the formation of salts, which, however, are
mostly uncrystallizable, or crystallize with diflficuliy, and are
quite unstable; the chromate is amorphous, and is characterized
by its very sparing solubility in water.
An aqueous solution of curarine, when carefully neutralized
with acetic acid, is precipitated by tannic acid, potassio-mercuric
iodide, auric and platinic chloriden, and most alkaloidal reagents;
it affords a copious yellow precipitate with j)icric acid, and an
orange-yellow precipitate with potassium chromate.
Curarine dissolves in concentrated sulphuric acid with a pale
violet color, which gradually changes to a dirty-red, and after
some hours assumes a rose-red color. If, to the solution in sul-
S34
. OP ClIBMICAL ANALYSIS.
fc
pliurJG acid, a crystal of potassium bichromate be adc
viulet coloration will be produced at the "poiiila of contact, but
which cUfl'ers from the similar reaction of stryclinine, produced
under the same circiimstancea, by its greater pennanunue. Willi
concentrated sulplmric acid, containing a trace of nitric acid, it
produces at first a brownish-violet, and Jinally a pure violet
coloratioij.
Curarine is distinguished from most alkaloids from the fact of
its not being absorbed, either from an acid or nn alkaline aolu-
lion, by ether, petroleum benzin, chloroform, or amylJc alcohol.
Its identification and purity may be established by the eonsidera-
lion of the above-dosoribed behavior towards reagents and sol-
vents; and its freedom from inorganic matter by the altsenoc of
any non-volatile residue, when strongly heated upon plaliDum-
foil
For the separation of cnrurine from other alkaloids, or for its
isolation when associated with other compK-x organic princjiples,
Bee page 111.
DiaiTALINUM.
Ger. Digilnlin ; Fr. Digllaliiie ; Bp. Digiuliiin.
Commercial digitalin varies somewhat in its physical and chemi-
cal properties, in consequence of different modes of preparation
and different grades of purity, and consists usually of a compli-
cated mixture of several distinct principles, with their products
of decomposition.
Qerman du/italin, which is mostly used in the United Stales,
forms yellowish-white or yellowish-brown porous scales, or a yel-
lowish powder, intxiorous, and of an intensely bitter taste ; he»te<I
upon platinum-foil, it burns off slowly, with intumescence. It is
soluble in water, forming a turbid, neutral liquid, whicli frotbs
upon agitation; it is also soluble in alcohol, partly so in chloro-
form, and insoluble in ether. Itri aqueous solution.' when slightly
acidulated with hydrftchloric acid, becomes first turbid, and a
(loGculent while precipitate soon ensues, especially upon gentle
warming. When the liquid, after several houra,'is filtered off,
and supersaturated with sodium carbonate, it turns blue upon the
addition of one drop of dilute solution of cuprie sulphate, and,
when set aside, in a warm place, deposits, after a while, red cuprons
oxide.
When about two drops of the aqueous solution of digitalin are
mixed, in a test-tube, with four or five drops of strong liydro-
DIOITALINIJM. 335
chloric or sulphuric acid, the liquid remains at first clear, but,
when immersed in boiling water, it turns successively j-ellow,
yellowish-green, and then yeliowish-brown, and a i)recipitate is
formed, which, upon addition of water to the liquid, appears white,
with a slightly greenish tint ; the supernatant liquid shows the
same color. After some time, this tint disappears, and the pre-
cipitate as well as the liquid l>ecomes colorless. When the same
test is performed with a dilute solution of sugar and with hydro-
chloric acid, a similar reaction takes "place, but without the forma-
tion of any precipitate.
German dujitalin^ or the dU/italin of Wah^ is decomposed by
boiling with dilute hydrochloric or sulphuric acids, into sugar and
ditjitaletm^ the latter, by loss of water, being partially converted
into paradif/italetin, and also, by further decomposition, into sugar
and difjitaliretin,
Diyltalin prepared ly the process of Ilomolh and Quevenne^ or
French difjitalin^ consists, according to the authors, of a mixture
of digitalin, digitaline, and digitalose, and forms either a yellow-
ish white powder, or a white, porous, mammillated mass, or small
scales, almost insoluble in cold and warm water and in ether, but
readily soluble in alcohol and in acids ; it is also soluble in chloro-
form. If not already purified by solution in chloroform, and
subsequent evaporation, as it now occurs in commerce, this digi-
talin, when treated with chloroform, leaves an insoluble residue,
and the solution yields, upon evaporation, a crystallizable digi-
talin. Its solution in hydrochloric acid is of a faint-yellowish
color, but soon changes to green ; upon dilution with water, it is
decolorized, and digitalin separates in a resinous state. Its solu-
tion in nitric acid is at first colorless, but becomes yellow and
remains so after subsequent dilution with water. Sulphuric acid
dissolves it with a green color, disappearing upon dilution with
water. Moistened with sulphuric acid and afterward exposed to
the vapor of bromine, it assumes a violet color.
The crystallizable digitalin, or the diyiialein of Xativelle, is
obtained from its solution in chloroform in fine, colorless, shining
needles, intensely bitter, and, as claimed, of a far greater physio-
logical action; it gives an intense emerald-green coloration with
hydrochloric acid, is almost insoluble in benzol and in pure ether,
only sparingly soluble in water, soluble in 12 parts of alcohol, and
abundantly soluble in chloroform.
This crystallizable digitalin of Nativelle, however, is, according
to recent researches, not a simple body, but consists largely of two
distinct principles, to which the names of diyilvxln SiXid paradifji-
tofjenin have been applied.
Dif/itoxi\ CjjHjjO^, forms perfectly colorless scales or needle-
shaped crystals, insoluble in water, to which it di>es not even
impart its intensely bitter taste, as displayed in the alcoholic solu-
tion, and likewise insoluble in benzin and carbon bisulphide; it
336 MANUAL OF CDKMTCAL ANALYSIS.
IB Sparingly soluble in ether, more abundantly in chloroform, and
freely BoUible in alcohol, either cold or warm. It is not a ghico-
BiJe, but is very prone to decorn position by acids, either dilute or
strong, and is a powerful poison. When warmed with concen-
trated hydrochloric acid, it assumes the yellow or greenish hue
observed with commercial digitaiin; and when decomposed by
dilate acids in alcoholic solution, it is converted into loxirfsin, an
uocrystallizable, yellowish substance, readily soluble in ether.
The commercial digitaiin has been iikewiKe resolved into
three distinct substances, viz., diyilonin, di-jilalin, and diyitalein.
DiijUonin, Cj,Hj,0,„ is closeiy related in its composition and
properties to saponin; when boiled with dilute sulphuric acid
It yields two glucosidal principles, diyiloreain and diifitonem,
either of which, by prolonged boiling in alcoholic solution witb
dilute sulphuric acid, is converted into a crystallizable substance,
diyitogtnin, which dissolves in warm concentrated sulphuric acid
with a yellowish color, and displays a magnificent green fluor-
escence; from digilonin a crystallizable principle, paradiyito-
yenin, is obtained by the slow termentation of its solution, which
is closely allied to digitogenin, but differs from the latter by
assuming a brown color in contact with cold concentrated sul-
phuric acid. Diijitalin C,H,0, (Schmiedeberg), forms small, soft,
colorless grains, soluble in alcohol, alcohol containing chloro-
form, and in dilute acetic acid, but is sparingly dissolved by ether
or chloroform, nnd still leas by water, even wnen boiling, Ii is a
very active and poisonous substance, and is the prominent con-
Htituent of several kinds of commercial "digitaiin, " especially
that of Homolle and Qnevenne. It is a glucoside, and is resolved
by the action of acids into glucose and diyitaliresin ; the latter is
also a powerful poison, and ia capable of being further decom-
posed into sugar and another body, not yet thoroughly examined.
Diijitaleiv (Sclimiedeberg) bears some resemblance to the digi-
taiin of the same author, but differs therefrom bv being freely
soluble in water, and forming, like digilonin, a frothing solution ;
it differs also from digitonin by being readily soluble in Absolute
alcohol.
Commercial digitaiin may be recognized by the following re-
aotions: It is precipitated from its aqueous solution, if not too
dilute, by tannic acid ; and when a very small portion of it is dis-
solved in a capsule with concentrated sulphuric acid, and a trace
of bromine-water subaequentiv brought into the liquid, a violet-
red coloration is |iroduced. When a trace of digitaiin, together
witb a lillle purified ox-gall, is dissolved in a little water, in a
caiMulo, a small amount of concentrated sulphuric acid added, and
subsequently warmed at from 60 to 80" C. (140 to ITH" F.), the
solution gradually assumes a tine red color,
Digitulin is further characterized by its property of being ab-
ELATBRIMUM. 337
sorbed from an acid solution by ether, and much more readily
and completely by chloroform. It may thus be separated from
most of the alkaloids, and from other complex organic principles
with which it may be associated, as described on page 106.
SLATERINUM.
Slctterin,
Ger. Elaterin ; Fr. Elat^rine ; 8p. Elaterina.
C„H„0,; 348.
Small, colorless, shining, hexagonal scales or prisms, without
odor, of an extremely bitter, somewhat acrid, taste, and neutral
in their action upon litmus. They melt at 200^ C. (392° F.),
assuming thereby a yellow color, and solidify again upon cooling
to a yellowish, amorphous mass; when more strongly heated,
upon platinum-foil, they are decomposed, and finally completely,
dissipated.
Elaterin is insoluble in water or glycerin, soluble in 125 parts
of alcohol at 15° C. (59° F.), in 2 parts of boiling alcohol, in 290
parts of ether, and readily soluble in amylic alcohol, carbon bisul-
phide, and chloroform ; it is also soluble in concentrated aqueous
solutions of the alkaline hydrates and in ammonia-water, being
thereby converted into an acid body, devoid of drastic proper-
ties, and which mav be separated by supersaturating the solution
with a mineral acid.
With cold, concentrated sulphuric acid, elaterin assumes a yel-
low color, gradually changing to red; when evaporated to dry-
ness witli hydrochloric acid, the residue also assumes, with con-
oentrated sulphuric acid, a fine red color. When a few crystals
of elaterin are placed in a small porcelain capsule, and a few drops
of the liquefied crystals of pure carbolic acid are added, the ela-
terin is readily dissolved without the production of color ; if, how-
ever, two or three drops of concentrated sulphuric acid are now
allowed to flow into the mixture, an intense and beautiful carmine-
red color is developed, changing at first to orange, and, after some
time, to scarlet; the color is discharged by alkalies.
Elaterin is not decomposed by boiling with dilute acids (dis-
tinction from glucosides); its alcoholic solutions are neutral, and
are not precipitated by tannic acid, nor by solutions of metallic
salts (distinction from the alkaloids).
22
MANUAL OF CIIKMICAL j
EMETINL'M.
Emetine. Emetia.
Oer. EmrtiD ; Fr. Emetine ; Sp. EmeUna.
C„U^N,0,; 484.
Colorlcsp, hard, needle-shaped or tabular crystals, or a whitish
or vellowish-while, inodorous powder, possessing a slightly bitter
and acrid taste. The crystals melt at 62 lo 60" C. (143.6 to 149°
F,). When strongly heated upon platinum -foil, emetine burns
with a sooty flame, and la finally completely diKsipated.
CryBtallized emetine is soluble in about 100 parts of water,
more readily soluble in alcohol, ether, chloroform, and diluted
rtcids ; it has a strong alkaline reaction, and neutraliiiea acids with
the formation of salts, among which the hydrochlorate has been
(iblained in a crystalline form, whilst the nitrate, although amor-
phous, is characterized by its very sparing solubility in water.
The aqueous solutions of the salts of emetine, even when quite
dilute, are precipitated by tannic acid, potaasio-inercuric iodide,
platinic and auric chlorides, and most alkaloidal reagents; and
with solutions of the alkaline hydrates, carbonates, and bicarbon-
.'lies, amorphous precipitates of emetine are produced, insoluble in
an excess of the precipitant.
Concentrated sulphuric acid dasolves emetine with a green
coloration, which soon changes to yellow ; with concentrated huI-
puric acid containing ammonium molybdate in solution, it forms
tt red solution, which, however, soon changes to yellowish -green,
and, finally, to green. An aqueous solution of emetine assumes,
with a few drops of a freshly prepared saturated solution of chlo-
rinated lime, and the subsequent addition of one or two drops of
hydrochloric or strong acetic ac^d, a bright orange or lemon-yel-
low coloration. If a few drops of hydrochloric acid are poured
upon a little potassium chlorate, in a test-tube, and a drop of a
solution of emetine is added, an orange-red color, changing to
violet, is produced.
Emetine is further more particularly characterized by its strongly
emetic properties; it is distinguished from veratrine, which like-
wise exerts a violent emetic action, by ihe behavior of the latter
towards concentrated sulphuric or hydrochloric ac d, and other
special tests.
Emetine is absorbed by ether from its alkaline solution, and
may thus be separated from many other alkaloids, or from com-
plex organic principles with which it may be associated, in a form
RufBcieiilly pure tu admit of its subsequent identillcation, as
described on page \0H.
FBRRUM.
339
FBRRI AR8BNIA8.
FERRUM ARSENICUM.
Arseniate of Iron, Ferroso-ferrie Arseniate,
Ger. Arsensaures Eisonoxyd-oxydul ; Fr. Are^niate de fer ; Sp. Arseniato de
hierro.
When freshly prepared, an amorphous white powder, consisting
of ferrous arseniate, but which, owing to the absorption of oxygen
and the consequent formation of ferroso-ferric arseniate, quickly
assumes a green or greenish-blue color. When heated in a dry
test-tube, it first emits aqueous vapor, and afterwards affords a
crystalline sublimate of arsenious acid, whilst a dark-colored
semi-fused mass remains ; when heated upon charcoal, before the
blow-pipe, the characteristic alliaceous or arsenical odor is evolved :
and when heated in a dry narrow glass tube, Fig. 115, witii about
Fio. 115.
six times its weight of a mixture of equal parts of exsiccated
sodium carbonate and potassium cyanide, a bright mirror of me-
tallic arsenic is produced.
Ferroso-ferric arseniate is insoluble in water, but readily solu-
ble in warm hydrochloric acid, forming a yellow solution, which,
340 MANUAL OF CHEMICAL ANALYSIS.
when largely diluted with water, yields a Hue coloration i
iKith potassium ftTrocynnide and fepncyanidi.-, and, ujion satura-
tion with hydrogen sulphide, particularly upon warming, afibrds
a yellow precipitate of arsenic trisulphide. When boiled in a
solution of sodium carbonate, it yields a filtrate which, when
exactly neutralized with nitric acid, gives a reddish- brown pre*
cipitate with argentic nitrate, and a white crystalline one with
magnesium mixture.
Examinatioa :
A .small portion of the powder is shaken with a liule tepid
water, and the fiUrate lestect by evaporation on platinum -foil, bo
also with barium chloride; no fixed residue should remain in the
first instance, nor should a white precipitate be produced with
the latter reagent, as thereby an insufficient washing of the fer-
roso-ferric arseniate would be indicated.
FEBRI CABBOnAS SACCHARATU8.
FEBHIM CARUONICUM SACCHARATIM.
S'lfchiirattd CarliontU of Iron, or J/irroal Carbonalt,
Gcr. ZuckcrJialliKCB, knlilcuBnurpsElsmnxyitiil ;Fr. Sscchnrnredecnrbonalcde
fer ; Sp. Sicaruto de cmbonsto de Uiprro.
A greenisiigray powder, gradually oxidized by expowure to
the air, and having a sweet, feebly chalybeate taste. Heated
in a dry test-tube, it is charred, with the evolution of the vapors
and odor of burning caramel. When shaken with cold water,
this dissolves the sugar, and a little of the ferrous carbonate,
which may be precipitated, for the most part, as ferrous hydrate,
by boiling the solution; the powder is wholly and readily solu-
ble, with eflervescence, in hydr<x:hloric acid, forming a yellow
solution which gives, with reagents, the reactions of both ferrous
and ferric salts.
A s:icchnrated carbonate of iron which has a reddish color, and
afionU no brisk eft'ervcscence with acids, should be rejected,
Eumlnation :
Sodium carl/onaie and sulphates may be detected by shaking a
little of the powder with warm water, in a test-tube, filtering,8nd
evaporating the filtrate to dryness; the obtained residue is then
dissolved in a little dilute nitric acid, when effervescence will indi-
cate solnlle earfionates, and the resulting diluted solution, when
tested with barium chloride, will aflbrd a wliite precipitate it sul-
phates are present, both of which impurities would indicate an
insufficient washing of the preparation.
Copper and Zinc. — The portion remaining undissolved upon
the filter, after extractiou with water, as iu the preceding test, is
FBRRUM. 341
digested, in a test-tube, with a little solution of ammonium car-
bonate, for about one hour. The liquid is then filtered; a bluish
color of the filtrate would indicate the presence of copper^ and the
formation of a white precipitate upon the addition of a few drops
of ammonium sulphide, that of zinc.
If 8 grams of the saccharated carbonate of iron be dissolved
in water with an excess of hydrochloric acid, and the solution
mixed with 33 cubic centimeters of standard solution of potassium
bichromate (page 91), the mixture should still afford a olue color
or precipitate on the addition of solution of potassium ferricya-
nide, indicating the presence of at least 15 per cent, of ferrous
carbonate.
FBRRI CHLORIDUM.
FERRI PERCHLORIDUM. FERRUM SE8QUI-CHL0RATUM.
Chloride of Iron , Perehloride of Iron. Ferric Chloride.
9
Ger. Eisenchlorid ; Fr. Perchlomre de fer; 8p. Percloruro de hierro.
Fe,Cl,+12H,0; 540.2: or Fe,Cl,+ 6n,0; 432.2.
Orange-Bellow, crystalline masses, having a radiate structure,
and coutammg 12 molecules (39.93 per cent.) of water, or large,
brownish-red, rhombic tables, containing 6 molecules (24.94 per
cent.) of water of crystallization. The normal chloride, Fe,Clj -h
12H,0, melts at 36° C. (96.8° F.) to a liquid of a deep brownish-red
color; upon more strongly heating, it becomes partially decom-
posed, losing at first water and hydrochloric acid, whilst a portion
of the chloride sublimes in the form of anhydrous, brown, irides-
cent plates or hexagonal tables, which exhibit a red color by
transmitted, and a green metallic lustre by reflected light, and
leaving a residue of ferric oxide.
Ferric chloride is deliquescent, freely soluble in water, alcohol,
and glycerin, and also, but less readily, in ether and chloroform ;
it is abstracted from its aqueous solution by ether, and also, to a less
extent, by chloroform. A strong aqueous solution, of a spec. grav.
of 1.405, forms the officinal Liquor /erri chloridi. This, as well as
the solution of the salt, has an acid and strongly styptic taste, and
an acid reaction on test-paper ; when diluted with water, they give
a blue precipitate with potassium ferrocyanide, a white one with
argentic nitrate, and a bulky reddish-brown precipitate of ferric
hydrate, upon the addition of the alkaline hydrates in excess.
' Examfaation :
Ferric chloride should yield a complete and clear solution with
water and with alcohol; if a reddish, insoluble residue remains,
the chloride has undergone partial decomposition.
342
HAKUAl. OF GIIBMICAL ANALYSIS.
Ferrous chloride is detected, in the largely iHluted solution, by
the rormalion of a blue precipitate with potaassium ferrioyanide.
fixed Impurities, other Metallic Chiorides, and N'itric and Sul-
phuric Acidn, — A smiill portion of tbe ferric cliloridc is dissolved
in alKJUt ten times its weight of water, the solution heated to boil-
ing, and ammonia- water, in slight excess, subsequently added.
until the iron is completely precipitated, or until a liltle of the
clear .toiutioD no longer affords a blue coloration u|)on tLe addition
of a solution of jMitassium ferrocyanide. The ticiuid is then tillered,
and subsequently tested in separate portions as follow
Fixed impicrili'-» will be recognized by evaporating a portion of
the liquid to dryness, and strongly heating the residue upon
platinum -foil.
Copper and Zinc. — The presence of copper will be indicated by
a blue color of the aramoniacal solution, and, if present, the solu-
tion should be slightly acidulated with hydrochloric acid, and
subsequently saturated with hydrogen sulphide, when the cupper
will be completely precipitated as brownisli-black cupric sulpliide;
after the removal of the latter by filtration, the solution is a^ain
supersaturated with ammonia-water, and tested with ammonium
snlphide, when a white precipitate will indicate the presence of
zinc.
Sulphuric acid will be indicated by a white precipitate when a
portion of the diluted eolntion, sligliily acidulated with hydro-
chloric acid, is tested with barium chloride.
rKitric acid may be detected by slightly acidulating a portion of
the diluted solution with sulphuric acid, and by testing it, in two
portions, with solution of indigo and solution of potassium per-
FBRRUM. 843
inanganate ; a decoloratioa of the faintly colored solutions, upon
gently warming, would indicate nitric acid.
The presence of nitric acid may be confirmed by mixing a por-
tion of the solution, previously neutralized with sulphuric acid,
with a strong solution of ferrous sulphate, and by the subsequent
careful addition of concentrated sulphuric acid, so as to form two
layers (Fig. 116); a brown coloration at the line of contact of the
two liquids will ensue, if nitric acid or oxides of nitrogen be
present.
FBRRI CITRA8.
PERRUM CITRICUM OXYDATUM.
Citrate of Iron, Ferric Citrate,
Ger. Citronensaures Eisenoxyd ; Fr. Citrate de fer ; 8p. Citrate do liierro.
Fe,(C,H30,), + 6H,0 ; 597.8.
Thin, transparent scales, of a garnet-red color, permanent in the
air; when heated on platinum-foil, they are charred without fusing,
and without the evolution of an ammoniacal odor (distinction
from ammonioferric citrate) ; when completely incinerated, aided,
if necessary, by the addition of a few drops of nitric acid, red
ferric oxide, Fe^Oj, amounting to 26.76 per cent, of the original
weight, is left, which, when cool, should have no alkaline reaction
upon moist turmeric or litmus paper (distinction from potassio-
ferric tartrate).
Ferric citrate, is slowly but completely soluble in cold, and
readily in hot, water, and insoluble in alcohol ; its aqueous solu-
tion has a yellow color, a mild chalybeate taste, and an acid reac-
tion upon litmus ; it is not precipitated by ammonia- water, but is
rendered darker in color, and affords a precipitate of ferric hydrate
when heated with a solution of potassium hydrate; when largely
diluted with water, and slightly acidulated with hydrochloric
acid, it yields a deep blue color upon the addition of a few drops
of solution of potassium ferrocyanide.
Examination:
Ferric citrate when shaken with cold concentrated sulphuric
acid should not impart any color to the latter, even after several
hours, and should produce no effervescence when added to a cold
solution of S(xlium carbonate.
Aramonium salts, or an admixture of ammonio-ferric citrate,
may be detected by the odor of ammonia, when a little of the
ferric citrate is heated, in a test-tube, with a concentrated solution
of potassium hydrate.
Ferric tartrate may be detected by completely precipitating a
warm solution of ferric citrate with potassium hydrate, and test-
344 MANUAL OF CHEMICAL ANALYSIS.
ing the colorless filtrate by slightly supersaturating a portion of it
with acetic acid; when the solution is very dilute, it is first
reduced by evaporation, and, when cold, tested with a few drops
of a concentrated alcoholic solution of potassium acetate ; a white
crystalline precipitate, occurring at once or after some time, would
indicate tartrate. Another portion of the filtrate is precipitated
with calcium chloride, and altered; the filtrate, when heated to
boiling, should yield a white, granular precipitate of calcium
citrate, which rcdissolves on cooling, being confirmatory evidence
of the identity of a citrate.
FBRRI BT AMMONII CHLORXDUM.
AMMONIUM CHLORATUM PERRATUM. AMMONIUM
MURIATICUM MARTIATUM.
Amino nio- Chloride of Iron, Ammonio- Ferric Chloride,
Ger. Eisensalmiak ; Fr. Chlorure de fer et d^Ainmoniaque ; Sp. Clomro
de hierro y de amoniaco.
An orange-yellow, crystalline powder, somewhat deliquescent,
readily soluble in water or glycerin, and to some extent in alco-
hol, forming a yellow, transparent vsolution, which has an acid
reaction upon litmus. Its aqueous solution gives a copious rust-
brown precipitate with alkaline hydrates, and, when very dilute,
a dee[)-bluc one with potassium ferrocyanide, and a white, curdy
one with argentic nitrate; when heated with a concentrated solu-
tion of potassium hydrate, it develops the odor of ammonia, and
deposits ferric hydrate.
Examination :
One part of the salt should afford a complete and transparent
solution with five parts of water ; a reddish-brown insoluble residue
would indicate decomposition of the ferric chloride by exposure
to too strong a heat while drying the salt. The solution thus
obtained should not afford a blue coloration upon the addition of
two drops of a freshly prepared solution of potassium ferricyanide
(absence of ferrous salt).
Ziy^c and Copper. — The warm diluted aqueous solution is com-
pletely precipitated by the addition of ammonia- water in slight
excess, and subsc<iuently filtered ; a blue coloration of the liquid
will reveal the presence of copper: if the latter be absent, the
filtrate may then be directly tested with ammonium sulphide,
when a white precipitate will indicate the presence of ztnc ; if,
however, copper be present, the ammoniaoal lii^uid is first slightly
supersaturated with hydrochloric acid, and the copper completely
FBRRUM. 345
precipitated by hydrogen sulphide, when the liquid, after filtra-
tion, will afford upon the addition of ammonia-water a white
precipitate, if zinc be present.
FBRRI BT AMMONn CITRA8.
FERRUM ET AMMONIUM CITRICUM. PERRUM CITRICUM
AMMONIATUM.
Citrate of Iron and Ammonium. Ammonio-ferric Citrate.
Ger. Citron ensau res Eisenoxyd-Ammonium ; Fr. Citrate de fer et
d^ammoniaque ; Sp. Citrate de hierro amoniacal.
Thin, transparent, garnet-red scales, of a slightly sweetish and
astringent taste; they evolve, when heated, water and ammonia,
and, when completely incinerated upon platinum-foil, leave be-
hind about 25 per cent, of ferric oxide, which should not change
the color of moistened red litmus-paper (evidence of the absence
of potassio- ferric salts). Heated with a concentrated solution of
potassium hydrate, ammonia is evolved (distinction from ferric
citrate), and ferric hydrate is deposited.
Ammonio-ferric citrate is readily soluble in water, glycerin, and
diluted alcohol, but not in strong alcohol or ether ; its aqueous
solution is neutral or has a slightly alkaline reaction, remains un-
altered, or is but slightly darkened in color on the addition of
ammonia water, and is pot affected by solution of potassium ferro-
cyauide until after the addition of a mineral acid, when a deep
blue color or precipitate is produced.
Examination :
Ammonio-ferric tartrate may be recognized, as an incidental or
fraudulent admixture or substitution, by completely precipitating
a not too dilute aqueous solution of the salt with potassium
hydrate; the liquid is heated nearly to boiling, and, when cool,
filtered ; one portion of the colorless filtrate is examined by slighl
supersaturation with acetic acid, and by the subsequent addition
of a little alcoholic vsolution of potassium acetate, and allowing
the liquid to stand for some hours; the formation of a white,
crystalline deposit would indicate tartrate.
Another portion, of the filtrate is precipitated with calcium
chloride, filtered, and the filtrate heated to boiling. A white pre-
cipitate of calcium citrate, disappearing again on cooling, will
bear evidence of the identity of a citrate.
MANUAL OF CllBMICAL ANALYSIS.
FERRI BT AMMOKU SULPHAB.
SutpknU of Iron and A.
leva Alum. Ammonio- Ferric Sulphate.
Fe^NHj^SOJ, + 24H,0.
Pale-violet, octabeiiral crystalo (Fig. 86, page 213), containing
24 molecules (41.8 per ceat.) of water of crystallization, and efflo-
rescing by exposure to the air.
Exposed to heat, they undergo aqueous fusion, low the water
of crystallization, swell up, and leave a pale-brown residue. When
llie cryBtalB. or an aqueuua solution of the salt, is heated with a
concentrated solution of potasfsium hydrate, ammonia is evolved,
which may be recognized by its odor, and a precipitate of ferric
hydrate is produced.
Animonio-ferric sulphate is soluble in 3 parts of water at
15-' C. (59^ F.), and in 0.8 part of boiling water; it is less soluble
in glycerin, and insoluble in alcohol, ether, and chloroform. Its
aqueons solution has a slightly acid reaction, a sour, astringent
taste, and becomes partially decomposed on boiling, with the
separation of an insoluble, yeliowish-brown, basic salt; it yields a
blue precipitate witli potassium ferrocyanide, a brown one with
the alkaline hydrates, and a white one, insoluble in acids, with
barium nitrate or chloride.
When the solution of am monio- ferric sulphate is completely
precipitated with potassium hydrate, and the filtrate slightly
supersaturated with hydrochloric acid, it should not afford a
while, gelatinous precipitate upon the subsequent addition of an
excess of ammonia-water (absence of aluminium) ; the solution of
the salt, when completely precipitated by ammonia water, should
afford a filtrate, which, upon evaporation to dryness and subse-
quent ignition, should leave no permanent residue, nor impart a
violet color to the non-luminous flame (absence of potassium
salts).
FBRRI BT AMHONII TARTRAB.
Tartrate of Iron and Aminoni
0 Perrie TartraU.
Transparent, deep-red scales, of a sweet tasle, and of a nm-
brown color when reduced to powder; when healed in a teat-tobe,
rBRRUM. ' 847
the salt emits vapors of water and ammonia, and, when com-
pletely incinerated, bj exposure to a red heat, it leaves a residue
of ferric oxide amounting to about 25 per cent, of its weight.
Heated with potassium hydrate, it evolves the odor of ammonia,
and deposits ferric hydrate.
Ammonio-ferric tartrate is slowly but freely soluble in water
and in glycerin, but insoluble in alcohol and ether ; its solution is
neutral or slightly alkaline, remains unaltered, or is but slightly
darkened in color on the addition of ammonia- water, and, when col(),
18 not precipitated by the fixed alkaline hydrates or carbonates,
but is so upon boiling it with either of these reagents. Its solu-
tion is not rendered blue by potassium ferrocyanide, unless acid-
ulated with a few drops of a mineral acid. When completely
precipitated by potassium hydrate, the filtrate, if not too dilute,
gradually yields, after supersaturation with acetic acid, a white,
crystalline deposit of acid potassium tartrate, but should afford
no precipitate with hydrogen sulphide.
The aqueous solution of ammonio ferric tartrate, when acidu-
lated with a few drops of hydrochloric acid, should afford upon
saturation with hydrogen sulphide but a white turbidity of sul-
phur ; a dark turbidity woula indicate other metals (copper) ; if
required, the nature of the precipitate of the sulphides may be
ascertained, and the metals contained therein recognized, by the
method described on pages 52-56.
FBRRI BT POTA88II TARTRA8.
FERRUM ET POTASSIUM TARTARICUM. TARTARUS FERRATUS.
Tartrate of Iron and PoUmium, Pota$sio-FBrric Tartrate,
Gcr. Weinsaures Eisenoxyd-Kalium ; Fr. Tartrate de fer et de potasse ;
Sp. Tartrate de bierro y potasa.
Transparent, ruby-red scales, of a sweetish and slightly astrin-
gent taste; when heated, they emit at first the odor of burnt
sugar, and leave, upon incineration at a red heat, a residue which,
when cold, changes the color of moistened red litmus-paper to
blue, and effervesces when moistened with a drop of hydrochloric
acid.
Potassio-ferric tartrate is freely soluble in water and in gly-
cerin, but scarcely in alcohol ; its solution is neutral or slightly
alkaline, remains unaltered or is but slightly darkened in color
on the addition of ammonia-water, and, at ordinary temperatures,
ffives no precipitate with the fixed alkaline hydrates or car-
bonates, but, upon boiling, a reddish-brown precipitate of ferric
hydrate is produced ; with potassium ferrocyanide it affords no
343
MANUAL OF CHEMICAL ,
reaction until after the addition nf a mineral acid, when the solu-
tion, oven when very dilute, assumes a deep blue color. If tbo
iron bo completely precipitated from iho solution by boiling with
a solution of potasaium hydrate, and the filtrate slightly super-
saturated with acetic acid, it gives, un cooling, if not too dilute,
a crystalline deposit of acid potassium tartrate, but should afford
no precipitate with hydrogen sulphide. The aqueous solution of
[lotassio-ferric tartrate, when acidulated with a few dropa of
lydrochloric acid, should afford upon saturation with hydrogen
sulphide but a white turbidity of sulphur,; a dark turbidity would
indicate other metals (copper) ; if required, the nature of the
precipitate of the sulphides may be ascertained, and the metals
contained therein recognized, by the method described on pages
52-56. When heated with a solution of potassium hydrate, po-
tassio-ferrio tartrate should not develop the odor of ammonia
(distinction from ammonio-ferric tartrate).
FERRI ET QUININE! CITR&S.
CUININUM FERBi
Citrate of Iron and Qui'ni
ia. Quiairu Ftrrie Oilratt.
Thin, transparent scales, varying in their color from a yellowish-
brown, with a tint nf green, to a reddish-brown, according to the
thickness of the scales. When strongly heated, they are decom-
posed with the evolution of white fumes, and leave, upon incine-
ration, a residue of ferric oxide, which should not change moist-
ened red litmus-paper (evidence of the absence of alkaline
citrates).
Quinine ferric citrate is slowly but freely soluble in cold, and
readily in hot, water, but insoluble in afcohol and ether ; its
solution ia neutral or slightly acid, and has a bitter, mild, cha-
lybeate taste; it gives, at ordinary temperatures, a white precipi-
tate of quinine with ammonia-water, and the solution assumes a
deej^wr color ; but no ferric hydrate is thrown down; when the
precipitate is collected upon a filter, washed with a few drops of
cold water, and then dissolved in a little chlorine-water, the solu-
tion will assume an emerald-green color upon the addition of a
few drops of ammonia-water (evidence of the presence of quinine,
and distinction from cinchonine and cinchonidtne). Solution of
quinine ferric citrate gives a brown precipitate of ferric hydrate
and quinine with a solution of potassium or sodium hydrate, and
with ammonia-water, when heated; a blue one with solution of
FERRUM. 349
potassinm ferrocyanide, when acidulated with a mineral acid, and
a grayish-black one with tannic acid.
Examination:
The absence or admixture of cheaper scaled ferric salts may be
ascertained:
1. By the bitter taste, while the other scaled ferric salts, with
the exception of strychnine ferric citrate, have a more or less
sweetish taste.
2. By the formation, in the cold, of a white precipitate with
ammonia-water, which responds to the tests and reactions of
quinine, while the ferric citrates and tartrates, and their more
soluble combinations with alkaline salts, yield, with the same
reagent, no precipitate at all at ordinary temperatures.
3. By giving no odor of ammonia, nor white fumes with a glass
rod, moistened with acetic acid, when heated in a test-tube with
a solution of poUissium or sodium hydrate. Any admixture of
ammonio-ferric salt would be recognized by this test.
In order to ascertain the purity of quinine ferric citrate or to
determine the proper percentage of quinine contained therein, the
following method of examination may be employed. Four grams
of the scaled salt are dissolved in 30 cubic centimeters of water,
in a capsule, with the aid of a gentle heat. The solution, after
being allowed to cool, is transferred to a glass separating funnel,
the rinsings of the capsule added thereto, then an aqueous solu-
tion of 0.5 gram of tartaric acid added, and the whole well mixed.
Solution of sodium hvdrate in considerable excess is now added,
and the precipitated alkaloid extracted by agitating the mixture
with four successive portions of chloroform of 15 cubic centi-
meters each. After being allowed to subside, the chloroformic
layers are separated, subsequently combined, evaporated in a
weighed capsule on a water-bath, and the residue finally dried at
100®' C. (212° F.), until it ceases to lose weight. The obtained
residue should weigh 0.48 gram, corresponding to 12 per cent, of
dry quinine.
FBRRI BT 8TRTCHNIN2I CITRA8.
FERRUM ET 8TRYCHNINUM CITRICUM. STRYCHNINUM
FERRO-CITRICUM.
Citrate of Iron and Strychnine, Strychnine Ferric Citrate,
Ger. Strychnin baltiges citronensaiires EiBcnoxyd ; Fr. Citrate de fer et de
strychnine ; 8p. Citrato de hierro y eBtricnina.
Thin, transparent, garnet-red scales, deliquescent on exposure
to the air. When strongly heated, they are decomposed with the
evolution of white fumes, and leave, upon incineration, a residue
SnO MANUAL OF CIIBMICAL ANALYSIS.
of ferric oxide, which should not change moistened red litmufl'
paper (evidence of the absence of alkaline citrates).
Strychnine ferric citrate is readily and completely soluble in
water, but only slightly soluble in alcohol. Its aqueous solution
possesses a slightly acid reaction, and a bitter, mild, chalybeate
taste ; when heated, in a test-tube, with a concentrated solution of
(WJtassium hydrate, it develops the odor of ammonia, and a brown-
iah-red precipitate of ferric hydrate is produced. Ifthe solution of
the salt be boiled with an excess of solution of potassium hydrate,
filtered, and the coucenlrated and cooled filtrate precipitated by
solution of calcium chloride, and again filtered, the filtrate thus
obtained, when heated to boiling, will yield a white granular pre-
cipitate of calcium citrate, which, however, becomes mostly redis-
solved on cooling. The dilute aqueous solution of the salt is not
affected by solution of potassium ferrocyanide until after the
addition of a mineral acid, when a deep blue color or precipitate
is produced.
Examinatioii :
The identity of strychnine ferric citrate may be determined and
its purity approximately ascertained by dissolving 1 gram of the
salt in about four times its weight of water, adding thereto 1 gram
of a concentrated solution of potassium hydrate, and agitating the
mixture with small successive portions of chloroform ; the chlo-
roformic layers are separated from the aqueous mixture, and,
after evaporation, should leave a residue answering to the reac-
tions and tests of strychnine, and corresponding in amount to one
per cent, of the weight of salt emploved.
purr: ferroctanidum.
ferrum ferrocyanatum.
Ftrroryanide of Iron. Prnniuii Blue. Ftrric FeiToej/anidt.
Fe,(CN)„ - 3[Fe(CN),] + 4[Fe(CN),] ; 859.3.
A deep-blue, tasteless powder, or hard, brittle, blue masses,
showing, on the freshly fractured surfaces, a beautiful bronzed
lustre, which disappears when they arc powdered. Wlieu iieated
in the air, it burns with the development of colorless vapon,
emitting ilie odor of ammonia and hydrocyanic acid, and leaving
a residue of ferric oxide; exposed to a high temperature in a
closed vessel, il gives off water, ammonium cyanide, and ammo-
nium carbonate, and carbide of iron is left behind.
Ferric ferrocyanide is insoluble in water, glycerin, and alcohol,
and in diluted auids, with the exception of Oxalic acid, which dis-
FBRRUM. 351
solves it, with a deep-blue color. Concentrated sulphuric acid
converts it into a white pasty mass, which again assumes a blue
color upon the addition of water; it is also decomposed by con-
centrated hydrochloric and nitric acids. Alkaline hydrates and
carbonates decompose it, upon heating, with the formation of
soluble alkaline ferrocyanide, and leaving rust-brown ferric
hydrate behind.
Commercial Prussian blue is not invariably pure ferric ferro-
cyanide, but generally contains aluminium and potassium salts,
and frequently some uncombined ferric hydrate. These impuri-
ties may be detected by boiling the triturated Prussian blue with
dilute hydrochloric acid, and adding to the filtrate an excess of
ammonia-water, when the hydrates of aluminium and iron are
precipitated, while pure ferric ferrocyanide, treated in this man-
ner, yields no precipitate. If it is desired to examine the precipi-
tate for aluminium, it is collected upon a filter, washed, and treated
with a warm solution of potassium hydrate; the filtered solution
will then aflf'ord a white flocculent precipitate upon the addition
of a solution of ammonium chloride, if aluminium be present.
Examination :
Mineral Admixtures, — A small portion (about 2 grams) of the
ferric ferrocyanide is heated, in a porcelain crucible, to redness;
when cool, the residue is treated with warm hydrochloric acid,
which should afford a complete and clear solution, with slight
effervescence ; an insoluble residue would indicate fixed mineral
admixtures (calcium or barium sulphates or silicates).
Metals, — To the solution obtained in the preceding test, a little
potassium chlorate is added, and the solution boiled until the odor
of chlorine ceases to be evolved; it is then diluted, filtered, and
the filtrate divided into two portions ; these are heated, and the
one is precipitated with a solution of potassium hydrate, the other
with ammonia-water, in excess ; after a while, they are filtered, and
each of the alkaline filtrates is tested with ammonium sulphide ; a
black precipitate, in the potassa solution, would indicate lead; a
blue coloration of the ammoniacal liquid, and a brownish-black
precipitate upon the addition of ammonium sulphide, will indicate
copper; a white turbidity, in either of the liquids, upon the addition
of ammonium sulphide, shows zinc to be present. For the detec-
tion of zinc in the presence of lead or copper, the alkaline solution
must be first slightly supersaturated with hydrochloric acid, and
the lead or copper subsequently completely precipitated by
hydrogen sulphiae; the liquid, after filtration, will then afford,
upon the addition of ammonia-water, a white precipitate, if zinc
be present.
Earthy Carlo7i a tes . — The ammoniacal liquid of the preceding test
for copper and zinc, from which the latter, if present, have been
completely removed, either by saturation with hydrogen sulphide
or by the addition of ammonium sulphide, is tested with ammo-
352 MANUAL OF CHBMICAL ANALYSIS.
nium carbonate ; an ensuing white precipitate would indicate the
presence of liirium or calcium ; after the removal of the latter by
liltration, solution of sodium phosphate is added, when the forma-
tion of a white crystalline precipitate will reveal the presence of
mafjnesium.
FERRUM HYPOPHOSPHOR08UM.
ffypopho$phite of Iron, Ferric HypophoMphite.
Ger. Unterpbospborigsaures Eisenoxyd ; Fr. Hypopbospbite de fer ;
8p. Hipofdflfito de bierro.
Fe,(H,PO^^; 501.8.
A white or grayish-white, odorless powder, permanent in the
air; when heated, in a dry test tube, it evolves spontaneously
inflammable vapors of hydrogen phosphide, with considerable
intumescence, leaving behind ferric pyrophosphate; when heated
with a solution of potassium or soiiium hydrate, it is decomposed,
and as§!umes a reddish brown color. Since hypophosphorous acid
is very prone to absorb oxygen, the salt is readily decomposed
by all oxidizing agents. Ferric hypophosphite is insoluble in cold
water, and, when dry, is but sparingly soluble in hypophosphorous
acid, but readily dissolves in that liquid when in the moist hy-
drated condition ; it is dissolved bv diluted hvdrochloric ac;d,
forming a yellow solution, which, when largely diluted, gives a
blue precipitate with potassium ferroc3'anide, and is also readily
soluble in solutions of ferric sulphate and of sodium hypophos-
phite, and unites with alkaline citrates to form compounds which
are readily soluble in water, and of a green color.
Eiamination :
Ferric jyfiosjJiate may be recognized by an insoluble residue
when a small portion of the salt is dissolved in acetic acid. The
acetic solution should afford no precipitate upon the addition of
solution of ammonium oxalate; an ensuing white precipitate,
soluble in hydrochloric acid, would reveal the presence of cul-
cium.
FERRI lODIDUM.
FERRUM lODATUM.
Iodide of Iron. Ferrous Iodide.
Ger. EiscDJodur; Fr. lodure de for ; Sp. loduro de hierro.
Fel,; 309.1.
Opaque plates or masses, of an iron-gray color, metallic lustre,
and crystalline fracture, or, when obtained by the careful evapo-
FBRRUM. 353
ration of its concentrated aqueous solution^ bright green crystals,
having the composition FeI,+4HjO, which rapidly suffer oxida-
tion. When heated in a dry test-tube, ferrous iodide fuses, and
emits violet iodine vapors, finally leaving behind ferric oxide.
Ferrous iodide is very deliquescent ; it is soluble in its own
weight of water, and also in alcohol and glycerin, forming yellow-
ish-green solutions, having a styptic taste; its aqueous solution
gives a copious blue precipitate with potassium ferricyanide, and,
after the addition of a minute quantity of chlorine-water, assumes
a fine blue color upon the addition of a little mucilage of starch.
Ferrous iodide and its solutions rapidly oxidize, the latter forming
a rust-brown sediment, the former becoming less soluble in water,
and yielding a brown solution, one drop of which, when diluted
with a little water, and subsequently shaken with a few drops of
chloroform, imparts to the latter a beautiful violet coloration,
which, however, is not the case when the ferrous iodide is fresh,
and not yet partly oxidized.
Ferrous iodide is decomposed by, and therefore incompatible
with, acids, the alkaline hydrates and carbonates, and those
metallic salts which form insoluble iodides.
The oxidation of ferrous iodide is greatly obviated by its ad-
mixture with sugar. Upon this fact, the preparation of Ferri
lODiDUM SACCHARATUM and of Syrupus FERRI lODiDi are based ;
both share the chemical properties and reactions of the ferrous
iodide. The syrup may be preserved without decomposition,
when kept in a sunny place, in small, well-corked vials, containing
a piece of clean, bright iron wire.
FERRI LACTA8.
FERRUM LACTICUM.
Lactate of Iron. Ferrous Lactate.
Ger. Milcbsaures Eisenoxj'dul ; Fr. Lactate de fer ; Sp. Lactato de hicrro.
Fe(C3H,03),+3H,0; 287.9.
Greenish- white, needle-shaped crystals, crystalline crusts or
grains, or a greenish- white powder,* containing three molecules
♦ The ferrous lactate of the German manufacturers and shops occurs as a
yellowish or grayish-grccn powder, and is obtain<'d by the following process,
which is least subject to the fornialion of peroxide :^ An alcoholic solution of
sodium lactate is exactly decomposed by a concentrated aqueous solution of
ferrous chloride. Allowed to stand for twenty-four hours, in a filled and
closely stoppered bottle, in a cool place, the ferrous lactate separates in a thick,
crystalline crust, which, after the mother liquor has been removed, is broken
by a wooden spatula, and then transferred to a cloth, washed with a little alco-
hol, and afterward subjected to a moderate pressure, under a small screw-press.
The resulting salt cake is broken, dried at a gentle heat, and finally triturated.
23
354 MANUAL OF CHEMICAL ANALYSIS.
(18.8 per cent.) of water of crystallization, which are eliminated,
without decomposition of the salt, by heating to 100^ C. (212^ F.)
in a current of hydrogen. When heated, with exposure to the air,
the salt acquires at temperatures above 60° C. (140® F.) a gray or
brownish color, becomes finally black, and, at 100** C. (212° F.^
is chiefly converted into ferric salt ; when more strongly heated,
the salt froths up, with the evolution of white, acid, inflammable
fumes, becomes black, and, when completely incinerated, leaves a
residue amounting to 27.8 per cent, of its weight of red ferric
oxide, which, when cold, should not act upon moistened red
litmus-pa] er (evidence of the absence of alkaline salts).
Ferrous lactate is slowly soluble in 40 parts of water at 15^ C.
(r>9° F.), and more readily in 12 parts of boiling water, but is
almost insoluble in alcohol. Its aqueous solution is more or less
turbid, and of a yellowish-green color and acid reaction, and has
a mild, sweetish, chalybeate taste; by exposure to the air, or
more quickly upon boiling, it assumes a brown color, in conse-
(|uence of its oxidation to ferric salt, and, upon protracted boiling,
ferric hydrate is deposited. The concentrated aqueous solution of
the salt aftords upon the additicm of solution of the alkaline
hydrates a yellowish precipitate of ferrous hydrate, and yields
when saturated with hydrogen sulphide, particularly upon warm-
ing, an abundant precijutate of ferrous sulphide. The clear,
llltered, aqueous solution should j^roduce up(»n the addition of a
few droi)s of a solution of potassium ferrocyanide but a slight
blue coloration, and should alVord with plumbic acetate but a
slight opalescence (evidence of the absence of more than traces of
ferric salt, and of sulphuric, hydrochloric, tartaric, citric, and
malic acids); when acidulated with hydrochloric acid, it should
alVord upon saturation with h3'drogen sulphide but a slight opa-
lescence (absence of foreign metals, lead, copper, etc ).
Examination :
In addition to the above-described characters and tests, ferrous
lactate should be further examined for the following substances:
Mihcral hnpnrities. — A small portion of the ferrous lactate is
c<»nipletely incinerated in a small porcelain crucible, and the resi-
due subsequently treated with boiling water and filtered; the
filtrate must neither act upon test-pa}>er, nor leave any residue
upon evaporation on ])latin;nn-foil. The ignited residue of ferric
oxide is then treated with warm hydrochloric acid, in which it
should be completely soluble, and the solution, after warming
with a few dro]>s of nitric aci<l, or the addition of a little chlorine-
water, is diluted with water, iiltered, heated to boiling, and linallv
completely precipitated by ammonia-water. The liquid, after fil-
tration, evap(>ration to dryness, and subse<|uent ignition, should
leave no residue; when tested with ammcuiium sulphide, a white
turbidity woukl indicate zlm\ and, after the addition of solution
FERRUM. 355
of sodiuin phosphate, the formation of a white crystalline precipi-
tate would indicate rnaynesium salts.
Gum, starch, dextrin, suyar^ and other carbohydrates may be
detected by their carbonization, becoming brown or blackish,
when a little of the ferrous lactate is strewn upon cold concen-
trated sulphuric acid, and shaken therewith, and, if necessary,
allowed to remain in contact for several hours; they may also be
detected by boiling a saturated aqueous solution of the salt for a
few minutes with a few drops of dilute sulphuric acid, and subf^e-
3uently neutralizing the solution with potassium or sodium hy-
rate; the filtered liquid, upon the addition of a few drops of
Fehling's solution, and heating to boiling, will afford a precipitate
of red cuprous oxide, if the above-mentioned carbohydrates be
present.
FERRI OXALA8.
FERRUM OXALICUM.
Oxalate of Iron. Ferroun Oxalate.
Gcr. Oxalsaiires Eisenoxydiil ; Fr. Oxalate de fer ; Sp. Oxalate de bierro.
FeC,0,-f H,0; 161.9.
A lemon-yellow, crystalline powder, permanent in the air:
when strongly heated in contact with air, it decomposes with a
faint combustion, and leaves a residue of red ferric oxide, amount-
ing to 49.38 per cent, of its weight.
Ferrous oxalate is almost insoluble in water, but readily soluble
in hydrochloric acid, affording a solution, which, when largely
diluted with water, produces a deep blue coloration upon the
addition of a few drops of a solution of potassium ferricyanide.
When boiled with a solution of sodium carbonate, filtered, the
filtrate supersaturated with acetic acid, and solution of calcium
chloride subsequently added, a white precijntate of calcium oxa-
late will be produced.
Examination :
Ferrous oxalate, when ignited at a red heat, in a small porce-
lain crucible, affords a residue which is neutral in its action upon
litmus; and, if the ignited residue be extracted with boiling
water and filtered, the filtrate should aflbrd no residue upon
evaporation. When a small portion of the salt is dissolved in
hydrochloric acid, the solution diluted with water, filtered, and
saturated with hydrogen sulphide, it should afford no dark color-
ation (absence of foreign metals, lead, copper, etc.); the acid solu-
tion warmed with a few drops of nitric acid, and subsequently
completely precipitated by ammonia- water in excess, and filtered.
i
356 MANUAL OF CHEMICAL ANALYSIS.
should afford a filtrate which is not rendered turbid upon the
addition of ammonium sulphide (absence of zinc)^ and, when evap-
orated and strongly heated, should become completely volatilized.
FERRI OXIDUM H7DRATUM.
FERRI PEROXIDUM HYDRATUM. FERRUM OXYDATUM.
HY^DRICUM FUSCUM.
Hydraied Oxide of Iron. Peroxyhydrate of Iron, Ferric Hydrate.
Ger. Eisenhydroxyd ; Fr. Sesquioxyde de fer hydrate ; Sp. Hidrato de per-
dxide de bicrro.
Fe,(HO),; 213.8.
A reddish-brown, tasteless powder, destitute of grittiness,
which, when heated in a dry test-tube, emits moisture, but no
acid va])ors. By exposure for several days to a temperature of
100° C. (212° F.), it forms a scarlet powder, having the compo-
sition Fe^O,lIj(2Fc203 + HjO), and the specific gravity 4.4545,
and, upon gentle ignition, is completely converted into red ferric
oxide, FcjOj.
Ferric hydrate is slowly but wholly soluble in moderately
dilute acids, even in acetic acid, without any considerable efferves-
cence (a small amount of carbonic acid being absorbed by its
exposure to the air) ; when dissolved in cold hydrochloric acid, the
solution, after dilution with water, yields a blue precipitate with
potassium fcrrocvanide, but should not afford a blue coloration
with potassium ferricyanide, and, upon saturation with hydrogen
sulphide, but a white precipitate of sulphur should be produced.
The acid solution, after complete precipitation by ammonia-water
in excess, and subsequent filtration, should yield a colorless fil-
trate, which afl'ords no precipitate upon the subsequent addition
of either ammonium sulphide, ammonium oxalate, or sodium phos-
phate (evidence of the absence of 2:mc, calcium^ and maynesiinn).
Examination :
Alkaline sulphates or chhrides may be detected by agitating the
ferric hydrate with a little warm water, acidulating the filtrate
with a few drops of nitric acid, and subsequently testing with
bnriiim chloride and nrgentic nitrate ; a white precipitate in either
case will reveal the presence of such impurities, which may result
from injperfcct washing, in its preparation from ferric sulphate or
chloride.
Anniionia will be detected by its odor, when a small portion of
the ferric hydrate is gently heated, in a test-tube, with a concen-
trated solution of potassium or sodium hydrate; and by the for-
mation of white fumes, when a glass rod, moistened with acetic
acid, is held over the mouth of the tube.
FERRUM. 357
Copper may be detected by a blue coloration of ammonia- water
or a solution of ammonium carbonate, when agitated with the
ferric hydrate, and subsequently filtered ; its presence may be
confirmed or recognized, when the result of the preceding test is
uncertain, by supersaturing the filtrate with acetic acid, and test-
ing it with potassium ferrocyanide ; a reddish-brown precipitate
would indicate or confirm the presence of copper. Other metallic
impurities, if present, will be indicated by the above-described
characters and test^, and, when required, their nature may be
determined, according to the systematic method of analysis, as
described on pages 51-61.
FERRI PH08PHA8.*
FERRUM PHOSPHORICUM. FERRUM OXYDULATO-OXYDATUM
PHOSPIIORICUM.
Phosphate of Iron. Ferrous Phosphate.
Ger. Phosphorsaures Eisenoxydul ; Fr. Phosphate de fer ; 8p. Fosfato de hierro.
Fe3(P0J,-hn,0; 375.7.
A fine, amorphous, tasteless powder, of a slate-blue color when
dry, but which, upon prolonged boiling with water, assumes a
greenish color. When neated in a dry test-tube, it gives oft' water,
and leaves a black residue.
Ferrous phosphate is insoluble in water, but soluVjle in the
mineral acids ; with phosphoric acid it forms a clear, colorless
solution, whilst its solution in hydrochloric acid, in consequence
of the contained ferric salt, a result of superficial oxidation, pos-
sesses a yellow color; the latter solution, when largely diluted
with water, consequently yields a blue precipitate with both
potassium ferricyanide and ferrocyanide, and, upon saturation
with hydrogen sulphide, aftbrds a slight white turbidity or opales-
♦ The phosphate of iron (Ferri Phoaphas) of the U. S. Pharmacopceia is a
mixture of ferric phospliate witli sodium citrate, prepared by dissolving so*lium
phosi)hate in a solution of ferric citrate, evaporating tlie solution to the
consistence of a tliick syrup, and spreading it on plates of glass, so that, on
drying, the salt may be obtained in scales. It thus forms thin, transparent
scales, of a bright green color, permanent in the air, hut becorainsr dark on ex-
posure to the light. It is readily and completely soluble in water, but insoluble
m alcohol. Its aqueous solution is neutral in its action upon litmus, yields a blutj
coloration with solution of potassium ferrocyanide, and, after acidulation with
hydrochloric acid, a blue precipitate; when heated with an excess of a concen-
trated solution of potassium hydrate, it yields a brownish-red precipitate of ferric
hydrate, and the filtrate, after snpersaturation with acetic acid, yields a light
yellow precipitate with solution of argentic nitrate (distinction from ferric pyro-
phosphate). The salt contains an amount of ferric phosphate corresponding to
about 13.5 per cent, of metallic iron.
:io8
MANUAL OF CHEMICAL ANALYSIS.
ceiice, due to the separation of sulphur, but no dark coloration
shnuld be pn>du(XMl.
Wiien ferrous phosphate is boiled in a solution of sodium car-
bonate, and filtered, a filtrate is obtained which, when exactly
neutralized with dilute nitric aci<l, ;xives a yellow precipitate with
ar^rentic nitrate, and a white crystalline precipitate with nia^xnc-
siuin mixture, hut. after acidulaiion with hydrochloric acid, should
atford upon ^saturation with hydrogen sulphide, either in the cold
or u[)on wanninir, no coloration or precipitate (a yellow turbidity
would indicati^ the pn»sence of arsenic).
Examination :
S'>diuin sulphate, left from insulTicient washing, may be de-
tected when a little of the powder is shaken with some hot water,
and the liltrate tested with barium chloride.
SfetaU. — A strong s«)lution t)f the powder in hydnxihloric acid,
after dilution with water, is saturatetl with hydrogen sulphide,
and set aside for a ftw hours, in a closed flask, in a warm place;
Fig. 117.
a slii/h? white turbidity (sulphur) will occur: a dark coloration
would indicate ^^Y>;/^r, a yellow one, arsenic^ which latter, in con-
nect icni with thf; above mentioned test, may be confirmed by the
odor when a little of the salt is heated upon charcoal, before the
FBRRUM. 359
blow-pipe, or by the formation of a metallic mirror, in a narrow-
tube (Fig. 117), upon heating the dried precipitate with about six
times its weight of a mixture of equal parts of exsiccated sodium
carbonate and potassium cvanide.
FERRI P7R0PH08PHA8.
PERRUM PYROPHOSPIIORICUM.
Pyrophosphate of Iron, Ferric Pyrophosphate.
Ger. Pyrophosphorsanrcs Eisonoxyd ; Fr. Pyrophosphate de fer ;
Sp. Pirofosfato de hierro.
Fe,(P,0,)3 + 9Ufi ; 1)07.6.
A white, tasteless powder, which, when heated in a dry test-
tube, loses water and decreases in V(Wume, but remains white. It
is insoluble in water, but soluble in hydrochloric acid, and in
sohitions of sodium pyrophosphate and of alkaline citrates; its
solution in dilute hydrochloric acid has a yellowish color, an<l
aftbrds a blue precipitate with potassium ferrocyanide, and, upon
saturation with hydrogen sulphide, a white turbidity, due to the
separation of sulpliur, but no dark coloration is produced. When
boiled with a solution of sodium carb.)uate, ferric pyrophosphate
assumes a reddish brown color, and yields a filtrate of the same
tint, but which becomes almost decolorized upon slight super-
saturation with acetic acid, and gives a dense, white preci])itate
with argentic nitrate (distinction from ferric orthophos[>hate,
which gives a yellow precipitate, and from ferric metaphospliate,
which gives a white gelatinous one).
FBRRI P7R0PH08PHA8 ET 80DII CITRA8.
FERRUM PYROPHOSPHORICUM CUM NATRIO CITRICO.
Pyrophosphate of Iron with Citrate of Sodium. Pyrophosphate of Iron in
Scales.
Ger. Pyrophoaphorsaures Eisenoxyd mit citronensaurem Natrium ; Fr. Pyro-
phosphate de fer et citrate de sonde ; Sp. Piroibsfato de liierro y citrato de
sodio.
Thin, apple- green, transparent scales, of a mild, acidulous, and
slightly saline taste, and permanent in dry air ; by exposure to
the light the scales lose their transparency and become darker in
color.
The salt is freely and completely soluble in twice its weight of
water, and is also soluble in glycerin, but insoluble in alcohol.
?A}(} MANUAL OF CHEMICAL ANALYSIS.
Ttif: 'iilnte aqueous solution is of a bright yellow color, almost
ta'-r'.-'.e.-.-*. rin«i neutral in its action upon litmus; it is not precipi-
tatod by arnmonia-water, but assumes with the latter a brown
co-oraiion. an«l when heated with solution of ]>otassium hydrate,
ill .'.itriit exc»'.-?s, yields a red-brown precipitate of ferric hydrate;
if Ui*: iron \}*: tiius completely precipitated from the solution, fil-
ier«^r'i. tiic tV.iniie supersaturated with acetic acid, and a few drops
of .^o'.uiion of argentic nitrate subsequently added, a white pre-
cipitate will be proluced (distinction from ferric phosphate).
TiiC solution atVords a blue coloration with solution of potassium
ferr«>«:yanidt;, and, after acidulation witli hydrochloric acid, a blue
pre<;ipitate is pro<luced ; when mixed with hydrogen sulphide-
water, no immediate change is produced, but the mixture soon
assumes a black color.
Tlie dry salt sliould neither protluce effervescence nor a dark
coloration when strewn u]>on cold, concentrated sulphuric acid
(absence of carbonates and of foreign organic substances). It
contains an amount of ferric pyrophosphate corresponding to
about 11.5 per cent, of metallic iron.
FERRI 8UBCARBONA8.
FERRUM CARBONICUM. FERRUM SUB-CARBONICUM.
Carbonate of Iron, Basic Ferrous Carbonate,
Gcr. Kohlensaurcs Eis(!Uoxydiil ; Fr. Sous -carbonate de fer; Sp. Carbonate de
liicrro.
A fine, amorphous, retldish-brown powder, without odor or taste,
which, in consequence of the absorption of oxygen ami the elimina-
tion olcarbonic actid gas, consists for the most part of ferric hydrate
(]>iigc iJotJ), witli small and varying amounts of ferrous carbonate.
When gently heated in a dry test-tube, it emits aqueous vapors,
which condense in the cooler i)arts of the tube, and which, when
tested witli blue litmus-pai»er, slu>ul<l not alter its color; uj)on
more stn)ngly heating, it is completely converted into red ferric
oxide, I'VjOj.
Carbonate of iron is insoluble in water, but readily and freely
soluble, with slight elVervescence, in warm, diluted hydrochloric
acid, forming a yellow solution, a few dro|)s of which, when added
to water, ini]>art to this the property of yielding a blue precipi-
tate with both potassium fernx-vanide and ferricvanide. Tiie
solution therefore alfords, with reagents, the reactions of both
ferrous and ft'rric salts.
Examination :
Ferri Subcarbonas is distinguished from Ferri Oxidum Hv-
dratum by its readier solubility in hydrochloric acid, accompanied
FBaRUH. S61
by active effervescence, and affording a yellow solution, whicli,
when largely diluted with water, yields a blue precipitate with
both potassium ferrocyanide and ferricyanide.
Alkaline sulphates may be detected by agitating a small portion
of the powder, in a test-tube, with a little warm water, and sub-
sequently filtering; the filtrate should leave no considerable
residue upon evaporation on platinum-foil, nor, when acidulated
with a few drops of nitric acid, should it j'ield a white turbidity
upon the addition of barium chloride,
Metals. — A small portion of the powder is dissolved in dilute
hydrochloric acid, the solution boiled with a few drops of nitric
acid, and subsequently precipitated by ammonia-water in slight ex-
cess, and filtered; a blue coloration of the filtrate will reveal the
presence of copper, and a white precipitate upon the addition of a
few drops of ammonium sulphide will indicate the presence of zinc.
FBRRI SULPHAS.
FERRUM SULFUIIICUM.
Sulphate of Iron. Firroui Sulphatt.
vitriol) 1 Fr. SulfMe de fer ;
FeSO,+ 7Hp; 277.9.
Transparent, pale bluish-green, monoclinic prisms (Fig. 118), of
the specific gravity 1.889, or, wJien obtained by precipitation, by
means of alcohol, a pale bluish-green, crystal-
line powder (Ferri iSuIpkas Pnecipitatna). Fia. 118.
The crystals are slowly efilorescent in dry air,
and by exposure to a moist atmosphere rapidly
absorb oxygen, becoming coated with a layer
of brownish-yellow, basic ferric sulphate ; they
contain seven molecules (45.32 j)er cent.) of
water of crystallization, six-sevenths of wliich
they lo.'Kj at a moderate heat, leaving a green-
ish or grayish white powder (Ferri Sulphas
Exsiccaliis). At a red heat, the seventh mole-
cule of water, and also the acid is expelled,
leaving behind red, anhydrous ferric oxide
{Capvl Mortwim).
Ferrous sulphate is soluble in 1.8 parts of water at \'>° C.
(59^ F.), in 0,3 part of boiling water, and is slightly soluble in
diluted, but insoluble in absolute, alcohol ; its aqueous solution
has a greenish-blue color, an unpleasant styptic taste, and a
ulightly acid reaction ; it readily absorbs oxygon, acquiring a yel-
Fio. 118.
3*J2 MASCAL OF CHSMICAL A5ALTSIS.
low *: •' >r. iT-i br'::'':::^:' ::*\!: Vr :":.e for.Tii::on of an iiisxiiV-e
bisic f^rr!': ^il:/:*i:e. ■*-;.:.■; i :.-r*:ri" f-rr::- ^ilpha:* reniain* in
.-o . r. : • i r^. v.- : : :. : - e i :.: e : .• -i. r- :-sr i re rr • is ?? :: . r» ris :e. Tne s >. anon
of ferrji^ *u':/.:i:-r. '■"!-'. li.-jtr'y ill i:-?!. zires a while precipi-
tate witl'i 'oifi i:n ■:':.*.•.-! ir. i '/ :■=: >--r •Jr::h pjtiss'uin ferrievaniie.
an 1. w :;.••» n -• '.••::■: ox i.zri. i v.i.te ■>-;■? ■*';:j the ferr.:«CTanide,
bat, :if:er li'::; I'.ition w!::, :: /ir >:•:.'. oric .v.-id. aff^r-ls no precipi-
tate upon SiVir-iiior: w".:'::. iivir •^•rr: si'.phile.
Examination:
yf'-J.nl'i. — A sraV/. poriior. >:' the sa'.t :« di^sDlveJ in ab^ut twice
its \i'''i:/'rjt of Wiiter. tiie = »* i:: m:: aeidi'.itei with a few «lrops of
hy'lnn;h!orie a':':!, anl 5 i*ose'4 i--':i*.y ?i: irate i with hydrogen sul-
|>ln«le : no precipitate, or bit i white t'lrbiiity «»alphur) should
b3 formed: a laric turbiiity wo 1. 1 inli::i:e CM;>/>er, ani perhaps
other metals. Tfie lioiM i* then tiiterel. evaooratei in a noree-
lain eapsiile until de: -rived of olor, subsequently bailed with a
few drops of eoneentratei nitric acid, and finally completely pre-
cipitated by ammonia- water, in considerable excess, and filtered.
The filtrate is subsequently tested with ammonium sulphide; an
ensuin^^ white turbidity would indicate zinc, a reddish-white one,
raau^innesr. Finriily. tlie liquid, after having been filtered, if such
reactions have occurred, is tested with ammonium phosphate: a
crystalline, white precipitate, occurring after some time, would
indicate via (lUKsiiira.
Crude commercial sulphate of iron is generally considerably
contaminated with metallic and earthv salts, and not fit for niedici-
nal use: it frequently contains the sulphates of zinc, aluminium,
and magnesium, and generally so much sulphate of copper as to
d<?|)osit a metallic cupreous film upon a bright blade of an iron
knife or spatula, when immersed for some hours in the aqueous
solution, acidulated with a few drops of sulphuric acid, and may
also contain arsenic.
Estimation :
TIkj purity of ferrous sulphate, as based upon the estimation
of the etpiivalent percentage amount of the therein contained
metallic iron, may be readily and very accurately determined
V()lum(»,trically. About one gram of air-dry and uneffloresced
crystals of the salt is accurately weighed, and dissolved, in a
beaker, in about 200 cubic centimeters of water, the solution
subscijucuitly acidulated with dilute sulphuric acid, and a stand-
ard solution of potassium permanganate (page 89) allowed to
flow into the licpiid from a burette until, with constant stirring,
the pink tint of the liquid remains for a time unchanged. The
factor of the permanganate solution havitig been previously ascer-
tained (sei^ pages 8J)-i)0), and the number of cubic centimeters of
the solution required for the complete oxidation of the ferrous to
ferric salt, as above described, being known, a simple calculation
will determine the amount of iron contained in the ferrous state
FERRUM.
3t)3
in the salt, or the percentage amount of pure, crystallized ferrous
sulphate.
Another method consists in dissolving 4.167 grams of the salt
in water acidulated with diluted sulphuric acid, and allowing a
standard solution of potassium bichromate (page 91) to flow into
the liquid, until a drop removed by means of a glass rod, and
placed on a porcelain plate, no longer gives a blue color with
solution of potassium ferricyanide ; the number of cubic cen-
timeters of potassium bichromate solution thus required, when
multiplied by 2, will represent the percentage amount of unoxi-
dized, crystallized ferrous sulphate.
Table of the percentage strength of soluthns of crystallized Ferrous
Sulphate (FeS0^4-7H/)) of different specific (jravities {Gerlarh),
Temperature 150 C. (59^ F.).
Sp«ciflo
' p.»i
■ cent, of
SpeclAc
' Per cent, of
Specific
' P«rc<*nt. of
gravliy.
1 F6SO4+7H0O.
1 _ _ _ _
Kravltj.
1 FeS04+7HsO. i
1 - - . _ . 1
gravity.
FeSO^+THjO.
1.005
1
1
1
1.077
1 '
14
1.155
27
1.011
!
2
1.082
15 '
1.161
28
1.016
3
1.088
16 >
1.168
' 29
1.021
4
1.094
17 ,
1.174
30
1.027
5
1.100
18
1.180
31
1.032
6
1.106
19 i
1.187
32
1.037
7
1.112
20
1.193
33
1.043
8
1.118
21
1.200
34
1.048
9
1.125
22
1.206
35
1.0.>4
10
1.131
23
1.213
36
1.059
11
1.137
24
1.219
37
1.065
12
1.143
25 '
1.226
38
1.071
13
1.149
26 i,
1.232
39
FBRRI VALBRIANA8.
FERRUM VALERIANICUM.
Valerianate of Iron. Ferric Valerianate.
Ger. Baldriansaures Eisenoxyd; Fr.Valerinate de for; Sp.Valcrianato
de hierro.
Fe,(C,H,0,)„Fe^On),; 931.6.
A dark, brick-red, amorphous powder, permanent in dry air,
and possessing the odor of valerianic acid. When gently lieated,
the salt loses its acid witliout fusing, but when rapidly heated in
a porcelain capsule, it fuses, emits inflammable vapors, and, when
incinerated, leaves behind ferric o.xide, which should not color
moistened turmeric-paper brown, nor dissolve in warm dilute
acetic acid.
Ferric valerianate is insoluble in water, and is only miscible
therewith after having been previously moistened with a little
3G4 MANUAL OF CHEMICAL ANALYSIS.
alcohol ; boiling water (lecom])Oses it, extracting the valerianic
acid, and affording a colorless filtrate, which reddens litmus-paper,
but does not become turbid upon the addition of ammonia- water,
either before or after saturation with hydrogen sulphide. Acids
decompose ferric valerianate, forming soluble ferric salts, and
setting free the valerianic ficid.
The so-called sobcljle valerianate of iron (Ferrum valerianicum
solubile) occurs in thin, reddish scales, and consists of neutral or
normal ferric valerianate, Fe^C^II^O,)^ + lOII^O ; it is likewise
insoluble in water, but is soluble in alcohol (distinction from ferric
citrate aud tartrate), and exhibits the same behavior by the action
of heat or boiling water as the above-described preparation, leav-
ing, however, a much less considerable residue upon ignition.
Examination :
Admixtures of ferric tartrate or citrate, impregnated with oil
of valerian or valerianic acid, may readily be recognized by their
solubility in water and insolubility in strong alcohol; the latter
dissolving the oil of valerian, or valerianic acid, if such be pres-
ent, which may be readily recognized by the odor, when a portion
of the alcohol is evaporated upon the warm hand, while a residue
will remain, responding to the tests of ferric citrate or tartrate, as
described on pages 343 and 347, if such admixtures be present.
FERRUM,
Iron.
Ger. Eisen ; Fr. Fer ; Sp. Hierro.
Fe; 55.0.
The source of the medicinal jjrej'jarations of iron is the refined
malleable wrought iron, of which the ]>iano-forte wire is among
the best coinniercial varieties. AVhen iron filings or turnings arc
omvloved instead of wire, care has to be taken that thev are not
derive<l from crude cast or pig iron, that they are free from rust,
and that they are not contaminate<l with copper or brass filings
from the workshops. Cast or pig iron may be recognized by the
evolution of gas of a noxious odor, and by a considerable black
residue, when the filings or turnings ar6 dissr)lved, in a test-tube,
in a mixture of equal parts of concentrated hy«lrochloric acid and
water. Au admixture of copper or brass filings may be recog-
nized, with approximate c.Ttainty, by close inspection, with a
mairnir\'inL''-«^lass, and bv chemical tests, as hereafter described.
In the pre]>aratioii of solutions of iron, which are subsequently
filtercil, filings of cast iron are not exactly objectionable: iron
tilin«js or turuiu'^s, howev«»T, which mav contain, or are liable to
contain, copper or brass filings, ought not to be employed for
FERRUM.
365
Pig. 119.
medicinal preparations, since copper is dissolved by boiling with
an excess of acid, notwithstanding the predominating presence of
iron.
Ferrum Pulveratum. — A fine, gray powder, of a dull, metal-
lic appearance, and having the specific gravity 7.78 ; when strongly
heated, with exposure to the air, it becomes oxidized to black
ferroso- ferric oxide, and increasing in weight, if the powder em-
ployed was pure and dry. Iron powder dissolves in a mixture
of equal parts of hydrochloric acid and water, evolving impure
hydrogen gas, of a faint odor, and leaving only a small insoluble
black residue ; the filtered solution has a light-green color, and
affords, when largely diluted with water, a deep-blue turbidity
with potassium ferricyanide, and almost white precipitates with
the alkaline hydrates and carbonates, which, however, rapidly
oxidize, and become green, and ultimately brown.
Examination :
Sulphur, phosphorus, and arsenic, may be detected, in iron pow-
der, filings, turnings, or wire, by the odor of the evolved gas, when
dissolved in dilute hydrochloric or sulphuric
acid, and by testing the gas thus evolved, either
with a strip of paper moistened with a solution
of plumbic acetate and placed over the mouth
of the tube, or by loosely inserting a cork pro-
vided with two strips of paper, one of whjch is
moistened with a solution of plumbic acetate,
and the other with a solution of argentic nitrate
(Fig. 119) ; the blackening of both the lead and
silver paper will indicate the presence of sul-
phur, whilst a blackening of the silver paper
alone may arise from the presence of either
phosphorus or arsenic.
The presence of sulphur may be confirmed
bv dissolving a portion of the iron in dilute
nitric acid, and testing the solution with bari-
um nitrate; a white precipitate of barium
sulphate will be produced if sulphur were pre-
sent. The presence of arsenic, if indicated by
the above test, may also be confirmed by the
application oi Marsh's test, as described on pages
33 to 36.
Phosjyhorus may also be detected by dissolv-
ing a portion of the iron in warm dilute hydro-
chloric acid, boiling the solution with a few
drops of concentrated nitric acid, and filtering,
whereby any carbonaceous or siliceous matter will remain prin-
cipally undissolved, and may be further examined. The solution
is then evaporated to remove the excess of acid, diluted with
water, again filtered, if necessary, and incompletely precipitated
866 MANUAL OF CHEMICAL ANALYSIS.
with sodium carbonate, avoiding an excess of the latter. The pre-
cipitate of ferric hydrate thus obtained (containing the plios-
phoric acid) is filtered oft', dried, mixed with about four times its
weight of exsiccated sodium carbonate, and ignited in a small
porcelain crucible. The fused mass is then digested with hot
water, the solution filtered, acidulated with hydrochloric acid,
and magnesium mixture subsequently added; tFie formation of a
white crystalline precipitate will reveal the presence of phos-
phorus, which, by tiie above treatment, is converted into phosphoric
acid.
MrUilh'c Impurities. — A portion of the iron is dissolved in dilute
hydrochloric acid, the solution boiled with a few drops of cou-
centratod nitric acid, and subsequently com])letely precipitated by
ammonia- water, in excess, and filtered. The filtered solution
should afford no turbidity u|)on the addition of ammonium sul-
phide ; a V)lue coloration of the ammoniacal liquid will reveal the
presence of copj/er, whilst a black precipitate with the last-named
reagent may indicate copper, cobalt, or nich'l, a flesh-colored pre-
cipitate, mantjanese, and a white precipitate, zinc.
Copper, zinc., and lead may also be detected, even when pre-
sent in very small amount, by dissolving a portion of the iron in
an excess of warm concentrated hydrochloric acid, filtering, if
necessary, and cautiously pouring upon the acid solution a satu-
rated aqueous solution of hydrogen sulphide ; the presence of
coi)por and lead will' then be indicated by a brown zone l>e-
low the line of contact of the two liquids, and as zinc, when
j)resent, is usually contained in the form of brass, the confirma-
tion of a contamination with copper would of itself render the
iron objectionable. I^ead may be specially sought for, when de-
sired, by adding to the solution of the iron in hydrochloric acid
a few dro]>s of sulphuric j^cid, then ammonia-water in slight
excess, agitating the mixture, and subse([uently adding four or
five times its vohunc of dilute sulphuric acid, and again agitating
well ; the presence of the smallest amount of lead will thus be
indicated by an opalescence, dependent upon the separation of
plumbic sulphate.
Black oxide of iron (ferroso- ferric oxide) and organic matter,
occurring as a contamination of powdered iron, may be detected
in the first instance bv its much less ready solubility in a mixture
of bromine and water, and, in the second instance, by the ignition
of the powder in a small glass tube.
Estimation :
The estimation of the [mrity of metallic iron, when free from
oxide, may be readily accomplished volumetrically, by dissolving
about 0.2 gram of tlie suVjstance in a small ilask, so arranged as
to i)revent the oxidation of the iron during solution (Fig. 120),
in about 20 cubic centimetersof dilute sulphuric acid, pouring the
solution, when cool, together with the rinsings of the flask, into
FBRRUM.
367
a beaker, diluting with water to about 100 Fio. 120.
cubic centimeters, and finally allowing a
standard decinormal solution of potassium
permanganate (page 89) to flow into the
liquid from a burette until, with constant
stirring, the pink tint of the liquid remains
for a time unchanged. The factor of the
permanganate solution having been pre-
viously ascertained (see pages 89-90), and
the number of cubic centimeters of the solu-
tion required to produce the above result, or
to elFect the complete oxidation of the iron,
being known, a simple calculation will deter-
mine the amount of pure metallic iron con-
tained in the specimen under examination.
Ferrum Reductum (Ferrum Ilydrogenio Rcductum). — Iron
powder, obtained by the reduction of ferric oxide or hydroxide,
or ferrous oxalate, by means of hydrogen, at a strong heat, forms
a very fine, gray, loose, lustreless powder, which, when strongly
heated, with exposure to the air, becomes oxidized to black
ferroso-ferric oxide ; when touched with a lighted taper it ignites
and burns, affording likewise, as a product of combustion, black
ferroso ferric oxide.
Reduced iron is readily and wholly soluble in warm diluted
hydrochloric acid, with the evolution of pure hydrogen gas,
which is without action upon paper moistened with a solution of
Elumbic acetate or argentic nitrate, and forming a solution which
as the same properties and deportment with reagents
as that of powdered iron. If the solution takes place
without a copious evolution of gas, and has, when
filtered, a yellowish appearance instead of a light-
green one, the powder was more or less oxidized, or
even so much so as to consist almost wholly of a mix-
ture of ferrous and ferric oxides.
Examination of Ferrum Rednctnm :
In addition to the above-detailed characters, re-
duced iron should respond to the following test : When
digested for half an hour, at ordinary temperatures,
with 25 times its weight of a solution of ferric chlo-
ride, of the specific gravity 1.3, in a glass cylinder
Erovided with a glass stopper (Fig. 121), the mixture
eing repeatedly shaken, the iron should become com-
pletely aissolved ; any insoluble residue (which may
consist of the oxides of iron or other foreign sub-
Htances) will, according to its amount, determine ap-
proximately the value of the specimen under exami-
nation.
Another test, which may be applied to the determin-
Fig. 121.
uWCml
-SI
V-»
-13
!P=
JftTTt; \J 'ZlKZ'.t-^ AJilTi'*.
V
- ,_ •■
•■ ••
f^
'. - r : • • ■
■ V ■
• ■ • - .
. . 1 • .
■•- ■••■■: ■■:
"■■-_"" V
: V ■ . - : " 1
■w i->:
- -i -I
■ T 1 - : . . -i-
/. . /
^■■.
I/. •
.. •.. r-:- . • - ^ '! •r>.-> -.•- : . v- ^ jr-^:^ o^'-r. \'^\
■'- -f-. r-: . J'-'-T': ■ .-: >" I'-r iv ■..■'^■: : ="-.r:. ^ -rr^f'v'rriiriif
•r ■ '>: 'ff >• •::-•"'■•:: :■:::'. .! :.i;' i :?:r'^.
: ■ J : ' . •■ r •>•-'.:/ •: r'v- • r r i •. : r-.- : . :" : m ! '• * * ' h v -. r A ■•*-
y7/ '/ "/V nt f0t*»r. #i# *•'/.' r »rttf,^f't' /**.• . o r ' '..•.' r j i : : i : x " 'i rv* •*' i. :c h
rr.;: . ../;•:. v •'; n.itr. ',r \r-'. ^••'«-:- A-.'^rr ::i ii ::tV-i. ni.iV he j^r-
f'/r.'.'i -' ';•': ;r l.:i;/ V» •fi-: '.'i-;* i/ i- •l-.-i' :.•"-••-: i iii-ivT iVrrurn pul-
EMtimation of Ferrum Eednctnm:
I. A ' '» . v«::i7"i* ;i'l -ir;i:'>.' ra"*!i»l fir ''n? osv^ni^tion of the
t
:jf»:'ii i' 'if jrir'* r;i':-.i.!i': :r'^:i ;:i f'»:rrj':i r»; l=i .••;i:n. anl whicii ]in>-
v.'l« ^'«r :•-? :!'i':i:x':jr'- vitli O.-m-rj-tV-rri*! ox:«ir, Ke,0^, but not
f'fF Ni' 'iMirr '>x 'I'r- or tii'rir r'lrriMriM.ti'His. i* as f«»y.'»\vs: About
Ox 1// 'I ;; i'r-iffi '#r firrr'ifn r'r'liir-ruiii. nwnr.itt.'lv wfiizhed, toiretlier
wiMi .-1 I ttjr |,iin: ziii'-, ("iiboirt I ;?rarrn. jire 'lissnlvo'l in ab«»ut 20
rf-iiWj/-. 'i-'itirfM-t*!'- iif riiiiit^* >iil|i}iiirir; ii\:\i\, in a «mall flask, so
;irr;iri;" •( ;i- \n pn'V<;iit tin; ox illation of xXir iron during solution
(Ki;/. J/*'. \y-\'/*'. o07;. TIj<; .-olutioii, aftnr b'.'iiiLr alli»wo<l to cool, is
ti:iii lir/' 'I io ;i lirakor, aii'L to^^^*tli«*r with the rinsings of the
\\a k, «liIiiN*'l to thr, iiirayun* of 100 cubic <*cntiinetcrs: a stancianl
«h-c.in'irm:i! :-MlMtion of |n#tassiuiii jJcrmanL^anato (page 81>) is then
allovv'l t<r \\it\K iiitir the li(|ui<1 from a burettr until, with con-
i-laiil .iirriii;'. tin* \\'\\\\i tint of the li«|ui<l remains for a time
ihicIi.'iii'mmI. 'V\h\ factor of th<* |f(^rnianjjanate solution having
b.'i'ii |»n'viMiislv asr,«*Tiain"'i| ('|>:il'«^s >S!» -*.MI), the nnuibcr of cubic
«'riitiiiM'lrr> of t lie s«ilntiiin <'ni|i]oye«l will inilittate, by simple cil-
riilatitMi, tin- tni.il anioiuit of iron present, from which the per-
«*rnla"i- irriiHiiit «»f I lie lattt»r mav i»e <lctcrmineil. In consi<leration,
howi'vrr. thai the <Mitire amount of iron •letermined was not
tu'ii'inally present as mt'lallie in»n, but associat4»<l in part with fer-
rosn ferru* «i\ii|e, Ki'O^, which becomes recbu'ed to ferrous salt
llironi'Jj tlie a'^ency of the n:us<.'ent hydrogen, the number 72.4
FBRRUM. 369
should be subtracted from the total percentage of iron, and the
rennainder divided by the decimal 0.276, which will yield, as the
quotient, the percentage of pure metallic iron contained in the
specimen under examination.
II. Another method, which is based upon the determination of
the amount of metallic copper precipitated by a definite amount
of reduced iron from a solution of cupric sulphate of known
strength, and which requires no correction, as in the above method,
for the presence of ferrous or ferric oxides, is as follows : 1 gram
of the reduced iron is digested for one hour with a solution of 5
grams of pure cupric sulphate in 25 grams of water, acidulated
with 2 drops of dilute sulj)huric acid ; the solution is then filtered
into a previously weighed flask, the filter washed with sufficient
distilled water to obtain 50 grams of filtrate, 1 gram of pure pow-
dered iron (the percentage of carbon contained in it should be
previously determined) added, and the whole digested until the
copper contained in the solution is completely precipitated in a
metallic state; 5 grams of pure concentrated .sulphuric acid are
subsequently added, and the mixture gently heated until the iron
is completely dissolved, when the precipitated copper will alone
remain, contaminated with a little carbon. The copper is re-
peatedly washed, by decantation, first with water, afterwards with
alcohol, and finally with absolute alcohol and ether; the flask is
then quickly dried, by the aid of a gentle heat, weighed, and from
the weight of the copper the carbon of the powdered iron (about
0.01 gram) subtracted. Since the d!fterence between the weight
of this precipitated copper and the total weight of the metallic
copper (1.271 gram) contained in the 5 grams of crystallized sul-
phate equals the quantity of co{)per which was precipitated by
the metallic iron contained in 1 gram of the reduced iron, the
percentage of the unoxidized metal is readily determined from
the ascertained weight, and the relation between the atomic
weights of copper and iron. The number of centigrams of iron,
calculated from the copper which was precipitated in the first
part of the process, indicates directly the percentage of metallic
iron contained in the reduced iron.
This hook is the jyr*j,
COOPER MEDICAL Cl
SAN FRANCISOO. 0/...
OVfl in vot to J f> 7%'». I
368 MANUAL OP CHEMICAL ANALYSIS.
ation of ilie presence of a definite mininmm anioinn of metallic i
in the [ireparation, consists in digesting for two hours, in a glass
vessel, l).5 part of ferruin reduutum with a solution of 1,13 parts
of iodine and 1.2 parts of potassium iodide in 25 pans of water;
if the solution, at the expiration of two hours, and wilh the eni-
ploymeiil of the ahove proportions, contains no free iodine, bnt ia
clear and of a pale greenish color, the jiresence of at least 50 per
cent, of metallic iron in the preparation is assured. The same
test may readily be extended in ite requirements by the applica-
tion, in the employment of 0.5 part of ferriim reduelum, of
0.226 additional part of iodine, with the proper proportionate
amount of potassium iodido, for each 10 per cent, of metallio
iron to be indicated.
The United States Piiarmacopoeia directs that if 1 gram of
reduced iron be digested with 3.5 grams of iodine, 2.5 grams of
pota.'^sium iodide, and 50 cubic centimeters of distilled water, for
two liours, the resulting filtrate should have a green color, and
should not be rendered blue by gelaiiniised starch {corresponding
to the presence of at least 80 per cent, of metallic iron).
The further testing of ferrrum reduelum for sulphur, phos-
jAorrti, iinenie, mtlaUic tmpttritif^, or other admixtures which
may be likely to oucur, or are otherwise indicated, may be per-
formed according to the methods described under ferrum pul-
veratum, on pages 365-316.
Estimation af Femnn Redootnm :
I. A convenient and simple method for tlie estimation of the
amount of pure metallic iron in ferrum reductum.and which pro-
vides for its admixture with ferrnso- ferric oxide, Fe,Oj, but not
for the other oxides or their combinations, is as follows: About
0.2 to 0,3 gram of ferrum reductum, accurately weighed, together
with a little pure zinc (about I gram), are dissolved in about 20
cubic centimeters of dilute sulphuric acid, in a small fla-ik, so
arranged as to present the oxidation of the iron during solutioa
(Fig. 120. page 3(}7). The solution, after being allowed to cool, in
transferrca to a beaker, and, together with the rinsings of the
flask, diluted to the measure of 100 cuhie centimeters; a standard
dccinormal solution of potassium permanganate (page 89) is ibea
allowed to flow into the liquid from a burette until, with con-
stant stirring, the pink tint of the liquid remains for a time
unchanged. The factor of the permanganate solution hntring
been previously ascertained (pages 89-90), the number of cubic
centimeters of the solution employed will indicate, by .limple cal-
culation, the total amount of iron present, from which ine per*
centage amount of the latter may be determined. In consideratioa,
however, that the entire amount of iron determined was not
originally present ftsmetalHciron, hut associated in part with fer-
roso feme oxide, Fe,0 , which becomes reduced to ferroua aalt
through the agency of the nascent hydrogen, the number 72.4
FERRUM. 869
should be subtracted from the total percentage of iron, and the
remainder divided by the decimal 0.276, which will yield, as the
quotient, the percentage of pure metallic iron contained in the
specimen under examination.
II. Another method, which is based upon the determination of
the amount of metallic copper precipitated by a definite amount
of reduced iron from a solution of cupric sulphate of known
strength, and which requires no correction, as in the above method,
for the presence of ferrous or ferric oxides, is as follows : 1 gram
of the reduced iron is digested for one hour with a solution of 5
grams of pure cupric sulphate in 25 grams of water, acidulated
with 2 drops of dilute sulphuric acid ; the solution is then filtered
into a previously weighed flask, the filter washed with sufficient
distilled water to obtain 50 grams of filtrate, 1 gram of pure pow-
dered iron (the percentage of carbon contained in it should be
previously determined) added, and the whole digested until the
copper contained in the solution is completely precipitated in a
metallic state; 5 grams of pure concentrated .sulphuric acid are
subsequently added, and the mixture gently heated until the iron
is completely dissolved, when the i)reeipitated copper will alone
remain, contaminated with a little carbon. The copper is re-
peatedly washed, by decantation, first with water, afterwards with
alcohol, and finally with absolute alcohol and ether; the flask is
then quickly dried, by the aid of a gentle heat, weighed, and from
the weight of the copper the carbon of the powdered iron (about
0.01 gram) subtracted. Since the d!fterence between the weight
of this precipitated copper and the total weight of the metallic
copper (1.271 gram) contained in the 5 grams of crystallized sul-
phate equals the quantity of copper which was precipitated by
the metallic iron contained in 1 gram of the reduced iron, the
percentage of the unoxidized metal is readily determined from
the ascertained weight, and the relation between the atomic
weights of copper and iron. The number of centigrams of iron,
calculjited from the copper which was precipitated in the first
part of the process, indicates directly the percentage of metallic
iron contained in the reduced iron.
This hook is the jyr*j,
COOPER MEDICAL IL
SAN FRANCISOO. 0/...
O.Vfl in not fo le T'*'' I
S70 MANUAL OF CHEMICAL ANALYSIS.
OLTCERINUM.
GLYCERINA.
Glycerin, Trintomic Propenyl Alcohol.
Gcr. Glycerin ; Fr. Glycerine ; Sp. Gliccrina.
CU,-OII
C.II.O, « C3H3(OH)3, or CII-OH ; 92.
CII,-OII
A colorless and odorless, thick, viscid, neutral liquid, of an
intensely sweet taste; when anhydrous, its spec. grav. is 1.2()7 at
15- C. (50° F.); that of commercial glycerin, containing from 5
to 10 per cent, of water, is from 1.25 to 1.237. When perfectly
anhydrous, and exposed to a temperature of 0^ C. (32° F.), it is
capable, un<ler certain conditions, of assuming the crystalline
form; the crystals have a specific gravity of 1.262. belong to the
rhombic system, and attract moisture with great avidity, becom-
ing finally liquefied at 10° C. (50° F.), while the melting-point ot
the perfect! v anhydrous crystals is apparently above 23° C.
(73.4- F.).
Glycerin is not volatile at common temperatures, but, when ex-
posed in thin layers, is perceptiV)ly volatilized at a temj)erature
of 1(MP C. (212° F.), and distils unchanged in vacuo, or with
aqueous vapor, under ])ressure; it boils, under ordinary atmo-
spheric pressure, at 290^ C. (554° F.), undergoing partial decom-
position, and emitting white, irritating, inflammable vapors,
which, when ignited, burn with a pale blue flame, leaving no
residue.
Glycerin is miscible, in all proportions, with water, solutions of
the alkaline hytlrates, alcohol, and ether diluted with alcohol, but
not with pure ether, chloroform, carbon bisulphide, or benzol; it
mixes with concentrated sulphuric acid, with the formation of ^?/ /•
/*fi^-(/L'r''^'^^ ^^^^i^3^^5\(^i^J\ _r)yr J which affords soluble salts
with the oxides of barium, calcium, and lead; with concentrated
nitric and hydrochloric acids, it suffers decomposition, becoming
either oxidized, or forming therewith compound ethers, as in
the case of the powerfully explosive, so-called nltrofjhjcvrhi^
^i^5(^^""^^-2)r Wlien heated with dehy<lrating siibstances (con-
centrated sulphuric or phosphoric aci<l, or acid potassium sul-
phate), glycerin is converted into the strongl}' irritating substance,
acrofn'u, CJl/),
Glycerin i>osses«es extensive powers as a solvent ; it dissolves
most substances which are soluble in water, although usually in
a less degree, but, in some instances, is a better solvent, as, for
instance, in the case of alum, borax, and carbolic acid; and dis-
solves readily many Siubetances which are insoluble or very spar-
OLrCERINUM. 371
ingly soluble in water, such as sulphur and mercuric iodides, bro-
nnine, iodine, quinine, morphine, and other alkaloids, as also many
metallic oxides, and prevents the precipitation of the latter from
their solutions by the alkaline hydrates.
It does not mix with fatty oils, and dissolves essential oils only
to a limited extent.
Examination :
A fatty or empyreximatic odor of glycerin is best recognized by
gently warming a little of the sami)le on a watch-glass, or in a
small porcelain capsule, or by the addition of a little dilute sul-
phuric acid.
Canesufjar, glucose, and mucilayes are indicated by a more or
less brown coloration of the glycerin, when mixed with twice -its
volume of concentrated sulphuric acid, or when mixed and heated
with a strong solution of potassium hydrate; they will also be
indicated by a considerable carbonaceous residue, when a little of
the glycerin is heated to boiling, in a small platinum capsule, and
the vapors ignited.
Glucose may be detected by the occurrence of a brick-red pre-
cipitate, when a little of the glycerin, diluted with an equal
volume of water, is heated with a few drojjs of an alkaline solu-
tion of cupric tartrate.
Cane-swjar is detected by the same reaction, when the glycerin
is boiled for a few minutes with an equal volume of dilute solu-
tion of tartaric acid, and the hot mixture tested with Feliling's
cupric solution.
Mucilatjes of gum, dextrin, or glue are indicated by the forma-
tion of a white turbidity, gelatinous or flocculent, when one
volume of the glycerin is mixed with four volumes of alcohol.
Metallic salts are detected by agitating one volume of the glycerin
with three volumes of a saturated aqueous solution of hydrogen
sulphide ; any impairment of the colorlessness or transparency of
the mixture would indicate metallic impurities; they may be dis-
tinguished, as to the group of metals to wh'ch they belong, by divid-
ing the liquid into two portions, and adding to the one a little
hydrochloric acid, and to the other ammonia-water. Copj)er, lead,
and tin will be indicated by the first test; iron, zinc, and alu-
minium, by the second. If a precipitate appears in either case,
and the nature of the impurity has to be ascertained, the test must
be repeated on a larger scale, and the metallic impurity deter-
minea by the methods described on pages 51 to 59.
Calcium salts may be detected in the diluted glycerin, by a
white turbidity when tested with ammonium oxalate.
. Ammonium salts, occasioned by the neutralization of an origi-
nally slightly acidulous glycerin with ammonia- water, may be
detected by the odor of ammonia when the glycerin is heated, in
a test-tube, with an equal volume of a concentrated solution of po-
tassium hydrate, and by the appearance of white fumes, when a
372 MANDAL OF CHEMICAL ANALYSIS.
glasR rod, moisteneil willi aeetio ncid, is lield over llie mnutli of
the tube.
Acids mill Hitir Salffi. — Wlieii rliluled witli twice its volume of
watrr, tlie snhition must leave litmuB-pa[>er unchanged ; it is then
examined in four wparate portions: for hydrochhrie acid and
chhridea, hy acidulating with nitric acid, and testing with argentic
nitrate; for sulphuric acid and sutjjiales, by lct<ting the second
portion, also acidulated with nitric acid, with barium nitrate ; for
oxalic arid, by testing the third portion, acidulated with acetic
acid, with calcium acetate or chloride; and for nilric acid and
nitratfs, by adding to the fourth portion a little acetic acid and
one drop of neutral indigo folutioii, and then warming the mix-
ture by dipping the test-tube into hot water; a decoloration of
the bluish or bluish-green lint of th« liquid will indicate free ■
nitric acid ; when the color remains unaltered, a few drops of con-
centrated sulphuric acid are added to the mixture while still
warm ; if decoloration takes place now (and the glycerin is free
from chlorates), nitrates are indicated.
Another, very sensitive test for nitric acid and nitrates, com-
bining llie test for chlorine, is to mix, in a test-tube, a little moui-
liige of starch with a few drops of solution of potassium iodide
(free from iodatc), atid a few drops of dilute sulphuric acid, and then
lo add a small portion of glycerin; when mixed together with a
glass rod, the liquid must remain eolorlesB ; a blue color would
indicate chlorine ; when the mixture remains colorless, a thin rod
of bright zinc is immersed in the centre of the fluid, with care
not to agitate the test-tube; if traces of nitric acid or nitrates be
present, a bluish coloration, issuing from the zinc, will appear.
Formir acid may be detected by the formation of a black de-
posit, when a mixture of the glycerin with an equal volume of
diluted ammonia-water and a little solution of argentic nitrate is
allowed to stand in a corked test-tube, protected from the light,
for twenty-four hours.
BtiltfTtc arid, and analogous fatty acids, will be indicated by an
acid reaction of the glycerin, and may be extracted therefrom by
agitation with ether, or may be recognized by the odor of etbyl
butyrate (similar to that of artificial essence of pine-apple), when
a mixture of two volumes of glycerin with one volume of a mix-
ture of equal parts, by volume, of strong alcohol and concentrated
sulphuric acid, is geiuly warmed by dipping the flask or teat-tube
into boiling water,
Esttmatitni of Olyoeriii in Wine, Beer, eto. ;
The separation and approximate estimation of glycerin in wine,
beer, and other similar liquids, may be accomplished by treating
the residue obtained by the evaporation of a measured portion of
the liquid, in a small glass flask, wiili a warm mixture of 1 part
of ether and 3 parts of alcohol, which extracts the glycerin,
together with some succinic acid and sugar. The liquid is then
HYDRARQVRUM.
873
filtered, if necessary, the filtrate neutralized with milk of lime,
the alcohol removed by distillation or evaporation, and the dry
residue again extracted with a warm mixture of ether and alcohol,
which, after filtration, is allowed to evaporate, upon the water-
bath, at the lowest possible temperature. The residue of glycerin
thus obtained, after being allowed to stand for two days over
sulphuric acid, is finally weighed. The glycerin may be subse-
quently tested for its identity, if desired, by rendering it slightly
alkaline with a dilute solution of sodium hydrate, and moisten-
ing therewith a fused bead of borax, contained on the looped end
of a platinum-wire: if the borax bead be subsequently held in a
non-luminous flame, a deep green tint will be imparted to the
latter.
Table of the quantity by weight of Water contained in 100 parts by
weight of Glycerin of different specific gravities.
Temperature IT.flP C. (63.50 F.),
Specific
Per cent.
gravity.
of water.
1.267
0
1.204
1
1.260
2
1.257
8
1.254
4
1.250
5
1.247
6
1.244
7
1.240
8
1.237
0
1.284
10
1.231
11
1.228
12
' Speciftc
Per ceot.
8peciftc
Per cent.
Specific
Per cent.
gravity.
' of Wfcter.
gravity.
of water.
gravity.
of water.
1.224
13
1.185
26
1.147
89
1.221
' 14
1.182
27
1.145
40
1.218
1 15
1.179
28
1.142
41
1.215
' 16
1.176
29
1.139
42
1.212
1 17 '
1.173
30
1.136
43
1.209
; IS
1.170
31
1.134
44
' 1.206
19
1.167
32
1.131
45
1.203
20 ;
1.164
33
1.128
46
1.200
21
1.161
84
1.126
47
1.197
' 22 1
1.159
35
1.123
48
I 1.194
23 '
1.156
86
1.120
49
1 1.191
24
1.153
37
1.118
50
' 1.188
25
1
1.150
38
H7DRAR07RI CHLORIDUM CORROSIVITM.
HYDRARGYRl PERCHLORIDUM. HYDRARGYRUM BICHLORA.
TUM. HYDRARGYRUM CORROSIVUM SUBLIMATUM.
Corrosive Sublimate. Corrosive chhride^ Perehloride^ or Bichloride of Mer^
eury. Mercuric Chloride.
Ger. QuecksUberchlorid ; Fr. Bichloruro de mercure ;
Sp. Bicloruro de mercurio.
HgCl^; 270.5.
Colorless, translucent, heavy, crystalline masses, when obtained
by sublimation, or small, well-developed Yhombic prisms (Fig. 122),
when obtained by crystallization from its solutions, and having
374 UANDaL of CIIKMICAL A!IALYSia.
a specific gravity of 5.403; ihev are permanent in the air, give a
dull, while streak when scratcned with a knife, fuse at 26o° C.
(50y^ F.), and volatilize wholly at 295"
FiQ. 133. C.(563^ F.), forming dense, white vapors,
^^^ which, on cooling, solidify in small, shin-
j^^^^ ing ncedle.s,
/!^^B^^^ Mtiruuric cliloriJu iff soluble in water,
/ ^r^^ !v.|uiring. ut 10" C. (50° F.), 15.22 parts,
/ ■ ^k :\< 2i}° C. (68° P.). 13.68 pans, at 60" C.
dm A (122=' ¥.), 8.81 parts, at 80'* C. (176-= F.).
« I > ill parts, and at 100° C. (212^ R), 1.85
V ■ ^^ imrts of water for eolation; it is less
\ I _^^ -I'luble in glycerin, 100 parta of which
N^^^^^^^ dissolve about 7 parls of the salt, but is
^^^^^r freclv soluble in aleohol and ether, ro-
^^ qi'irms, at 17" C. (62.6** F.), 2.5 parts of
alcohol, spec. grav. 0.830, and 4 parts of
ellier for solution, and is abstracted, for the most part, by the
latter, when agitated with ila aqueous solution. The aqueous solu-
tion reddens blue litmus- paper, and has an acrid, inetallic, styptio
taste ; upon the evaporation of the solution, by the aid of heal, a
portion of the salt becomes volatilized with the aqueous va|>orB.
lu the aqueous solution of mercuric chloride, the fixed alkaline
and earthy hydrates and alkaline carbonates produce, when added
in Bmall quantity, a reddish-brown preoipitate; when added in
excess, a yellow one; ammonia-water gives a white one; argentic
nitrate, a curdy white one ; iodides, wlien added in small quan-
tity, a yellowish, and in larger quantity, a vermilion-red one, sol-
uble in an excess of the precipitant; stannous chloride, when added
in small quantity, a white, and when added in excess, a gray pre-
cipitate. When an aqueous solution of hydrogen sulphide is
gradually added to a solution of mercuric chloride, the precipita-
tion takes place according to the proportions of the reagent and
the chloride, in progressive variation of color from white to yel-
low, orange, reddish brown, and black ; an excess of the reagent
produces at once & complete black precipitation. When the aque-
ous solution of mercuric chloride is rubbed upon bright copper,
it coats the latter with a brilliant metallic film. It forms white,
insoluble or sparingly soluble compounds with many organic
substances, as albumen, fibrin, gluten, etc.; and by exposure to
the light, particularly when in contact with organic substances
and when pi>3sessing an alkaline reaction, it becomes gradually
reduced to mercurous chloride (calomel), while its decomposition
is prevented or materially retarded by the presence of hydrochloric
acid or alkaline chlorides.
Mercuric chloride is soluble, without decomposition, in nitric,
hydrochloric, aud sulphuric acids ; and crystallizes from the solu-
tions on cooling, if they were saturated while hot. With the nllca-
UYDRARdYKUM.
375
Pig. 123.
'!4 > *» »
line chlorides it combines to form double salts, which arc mostly
well crystal lizable, and more readily soluble in water than mer-
curic chloride.
Examination :
The purity of mercuric chloride will, in most instances, be suf-
ficiently established by its conformity with the above described
physical properties, by its complete volatilization upon
strongly heating, and its relation to solvents, as also
by tlie several chemical tests.
Arsenic may be readily detected by digesting the
powdered mercuric chlor.de with ammonia-water, or
precipitating its aqueous solution by the latter, subse-
quently filtering, and, after ac'.dulating with dilute
sulphuric acid, testing in Marsh's apparatus, page 84;
or, after the concentration of the solution by evapora-
tion, the several tests for arsenious acid may be ap-
plied, as described under the latter, on pages 127 to 180.
The presence of arsenic may also be ([uickly deter-
mined by dissolving a small portion of the salt in
hot water, and adding to the solution, contained
in a long test-tube, an excess of a concentrated solu-
tion of sodium hydrate, and a few fragments of alumi-
nium wire or pure zinc; a cap of bibulous paper,
moistened with a drop of solution of argentic nitrate, is
then placed over the orifice of the tube (Fig. 123), and
the mixture gently heated ; an ensuing dark coloration
of the paper or the production of a dark metallic stain
will reveal the presence of arsenic.
Mercuroiis chlon'cle (calomel) and other insoluble im-
purities or admixtures, will be detected by their re-
maining undissolved, when the mercuric chloride is
digested or gently warmed with about twenty times its weight of
water.
H7DRAR07RI CHLORIDUM MITE.
HYDRA.UGYR1 SUBCIILORFDUM. HYDRARGYRUM CIILORATUM.
MERCURIU8 DULCIS.
Calomel, Mild chloride^ Sub- or Proto- chloride of Mercury. Mereuroun
Chloride.
Ger. Quecksilberchlorfir ; Fr. Protochlornre de mercure ; Sp. Protocloruro
de mercuric.
HgCl; 285.1.
Mercurous chloride varies in the minuteness of its particles,
and accordingly in its a})pearanco and in the energy of its physio-
logical action.
3tb MANUAL OF CHEMICAL ANALYSIS.
When obtained by aiihlimtition, it forms ponderous, yollowiaC'
while masses or tiakea, of a fibrous, crystalhne frftclure, yiolding
a lemon-yellow streak wlion scratcln^d with a knife, and having a
81>ecifio gravity of 7.176. Wiion reduced to a fine powder by
trituration and levigatiou, it has a dull-wbit« appearance with a
yellowish tint; it becomes slightly yellowish when triturated
with strong pressure in a porcelain mortar, and consists, when
seen under the miuroacopc, of cuniparatively large, transparenl,
kjryatalline fragments (Fig. 124).
Fio. 124.
Fin. 135.
Fia. 126.
/^^M'i
Prepared by eul/liinatton and by eonderunfion of the vajjor by a
current of air or steam, mercurous chloride (Hydrargyri Chlw-
ridum Mite vapore paratum) forms a perfectly while and less
ponderous powder (specific gravity 6.56), consisting of smaller
laminar particles, when seen under the mioroscope (Fig. 125).
Prepared by precipitation, mercurous chloride forms a fine
.snow-white powder, consisting of minute, amorphous* particles
(Fig. 126), which are not transparent, and Hre devoid of odor or
taste.
With regard to therapeutical action, mercurous chloride, ob-
tained by sublimation and subsequent trituration and levigation,
and consisting of the largest particles, has the mildest effect ;
next to this comes the calomel obtained by sublimation and con-
demnation by air or stcaiii ;f that obtnined by precipitation, and
having the minutest division of its particles, has the more power-
ful physiological action,
Mercurous chloride, when heated in a dry test-tube, is slowly
but completely volatilized with a faint noise and without fusioD.
It is insoluble iu the ct^immon solvents, but soluble to some extent
in saliv.'i, iu the pancreatic juice, in albumen, and animal secre-
• When obtained by pre dpi latin;: n solurlon of mercuric chloriJe wiUi sul-
pliurnuB-iidd eaa, tlit rtBiillins niercHrous chloride \a of n crjBtBlliup structnre.
^ No nllicr klndi of mercurous diloride cnnHSyet bo coosldercd oftlciniil<
itnd no olliers slinuld lie dlspenspil Tor internnl use. unli.'SB ordered or pr«-
icrlbeil, than •• Calumtl via humida paralum,^' or " Calomel preeipUatient
paratum,"
HYDRARGYRUM. 877
tions. When agitated with hot water, with alcohol, or with
dilute acetic^ hydrochloric, or nitric acids, it is not acted u[)on by
any of them. When boiled for some time with water, it suffers
slow decomposition into metallic mercury and mercuric chloride;
the decomposition being greater in extent when, instead of pure
water, solutions of the alkaline chlorides are employed.
The fixed alkaline hydrates and carbonates, and the hydrates
of the alkaline earths, reduce mercurous chloride to black oxide;
the same conversion of mercurous chloride to oxide is also occa-
sioned by its exposure to light, and by contact with many organic
substances. Concentrated boiling hydrochloric and sulphuric
acids decompose the salt; the former producing metallic mercury
and mercuric chloride, the latter mercuric sulphate and chloride.
Warm concentrated nitric acid also dissolves it gradually, with
the evolution of nitric oxide vapors, forming a soluticm of mer-
curic chloride and nitrate, which solution blackens bright copper
when dropped upon it, and coats it brilliantly when rubbed upon
it. Mercurous chloride is also soluble in chlorine-water without
acquiring a transient or permanent yellow color (distinction from
mercurous bromide).
Examination:
When heated in a narrow test-tube, mercurous chloride must
completely sublime, without previous fusion and without emitting
ammoniacal odors or yellow nitrous vapors.
Mercuric chloride may be most quickly detected by placing a
little of the mercurous chloride, previously moistened with water
to the consistemje of a thin paste, upon a piece of bright iron, and
allowing the mixture to repose thereon for one or two minutes;
if mercuric chloride is present, it will become instantly decom-
posed, and there will appear upon the iron, after the removal of
the mixture by rinsing with a little water, a deep, dull-black
stain ;* it may also be detected by triturating some of the calomel
with diluted alcohol, agitating the mixture in a test-tube, and
subsequently filtering through a moist double filter; the filtrate
must impart no stain to bright copper, nor yield any reaction with
hydrogen sulphide or with argentic nitrate.
Ammomated mercury (white precipitate) may be detected by
the development of the odor of ammonia, when the mercurous
chloride is heated, in a test-tube, with a concentrated solution of
potassium or sodium hydrate ; or, when the mercurous chloride
of the preceding test, remaining upon the filter, is rinsed with
diluted acetic acid through the broken filter into a test-tube, and
the mixture agitated for a few minutes and filtered. The filtrate
is then tested in separate portions with hydrogen sulphide and
* Pnre mercarous chloride will produce under the same circum<*tance8, by
prolonged contact with the iron, a slight grayish film upon the latter, which,
however, cannot be mistaken for the characteristic black stain produced by
the mercuric salt.
878 MANUAL OF CHEMICAL ANALYSIS.
argentic nitrate; a black turbidity in the first instance, and a
white one in the second, would indicate ammoniated mercury.
Non- volatile impurities, such as the sulphates or carbonates of
the alkaline earths, may readily be detected when a little of the
mercurous chloride is completely volatilized by strongly heating
in a test tube; any residue thus obtained may be further exam-
ined for its identification, if desired, according to the systematic
methods of analysis, as described on pages 51 to 61.
H7DRAR07RI C7ANIDITM.
HYDRARGYRUM CYANATUM.
Cyanide of Mercury, Mercuric Cyanide,
Oer. Qiiocksilbercyanid ; Fr. Cyanure de mercure ; 8p. Cianuro de mercurio.
Hg(CN).; 251.7.
Colorless, anhydrous, needle-shai>ed crystals, or lustrous quad-
ratic prisms (Fig. 127), transparent when freshly prepared, but
soon assuming a white and opaque appearance ;
Pig. 127. when perfectly dry, and carefully heated in a
dry tube, they become decom]>osed into me-
tallic mercury and a colorless inflammable gas
(cyanogen), which burns, when ignited, with a
purple flame; when quickly heated, a black
residue of paracyanogen, intermingled with
globules of mercury, is left behind, which,
however, upon more strongly heating, is com-
pletely dissipated : when the salt is humid,
traces of hydrocyanic acid, of carbonic acid,
and of ammonia, are also formed and evolved.
Mercuric cyanide is soluble in 12.8 parts of
water and in 14.5 parts of alcohol at 15° 0.(59-^
F.\ in i^ parts of boiling water and in 6 parts of boiling alcohol, but
almost insoluble in absolute alcohol and ether; its aqueous solu-
tion possesses a disagreeable metallic taste, and is decomposed by
hydrochloric acid and by hydrogen sulphide, with the liberation
of hvdrocvanic acid and the formation of mercuric chloride or
sulphide, but is not decomposed by dilute sulphuric or nitric
acid, and is not precipitated by the alkaline hydrates and
carbonates, bv ar^rentic nitrate, or bv albumen: stannous chlo-
ride, containing free hydrochloric acid, precipitates metallic mer-
cury with the evolution of hydrocyanic acid. The solution of
mercuric cyanide aflords no mercuric stain upon bright metallic
copper, unless the latter be previously m«)istened with hydro-
chloric acid ; it readily dissolves mercuric oxide, and, on evapo-
HTDKARQTRUM.
379
rating the alkaline solution thus obtained, small needle-shaped
crystals of an oxy-cyanide, IIg,0(CN),, are formed.
Examination :
Mercuric oxy cyanide is indicated by an alkaline reaction of the
solution upon turmeric-paper.
Mercuric chloride and other soluble mercuric salts may be de-
tected in the solution, by the occurrence of a transient turbidity
upon the gradual addition of single drops of solution of potassium
iodide, or by the production of a precipitate upon the addition of
the alkaline hydrates or carbonates.
HTDRARGTRI lODIDUM RUBRUM.
HYDRARGYRUM BIIODATUM.
lied Iodide of Mercury. Biniodide of Mercury, Mercuric Iodide.
Ger. Quecksilberjodid ; Fr. Bi-iodure de mercure ; Sp. Bi-ioduro de mercuric.
Hgl,; 452.9.
A heavy, amorphous, scarlet-red powder, or small, brilliant,
octahedral crystals, belonging to the quadratic system, and hav-
ing a specific gravity of 6.8. When gently heated in a dry tube
Fig. 128.
380 MANUAL OP CHEMICAL ANALYSIS.
(Fig. 128) to about 150° C. (302 ^ F.), mercuric iodide first becorasa
of a pure yellow color, then, wlieu near the melting-point, deep
orange, and finally melts al 253-254° C. (487.4-189.2° F.) to a
blood-red liquid; at this temperature the volatilizatioQ of the
ioflide begins, when it-sublimes undecompoaod in the form of yel-
low rhombic -scales, which pass into the red modification of oela-
hedral crystals, slowly <m cooling, and at once by concussion.
If the Ball be healed with solution of sodium hydrate, and a
little sugar of milk added, a precipitate of metallic mercury is
pri^iduced; and if heated with sulphuric acid and a little manga-
nese dioxide, the vapor of iodine is evolved.
Mercuric iodide is nearly insoluble in cold, and only very spar-
ingly soluble in boiling, water ; it is soluble in 130 parts of cold,
and 15 parts of boiling, alcohol, leas soluble in ether, and very
little in glycerin and in oils. Concentrated acids, and the solu-
tions of the alkaline hydrates, decompose it; it is freely soluble
in aqueous solutions of potassium and sodium hydrates, of potas-
sium iodide and cyanide, of mercuricchloride, and of sodium chlo-
ride and sodium hyposulphite; the latter solution deposit.3, upon
gently beating, if the solvent is not in excess, red mercuric buU
phide, while, upon boiling, black mercuric sulphide, mixed with
raercurouH iodide and metallic mercury, is separated. All its
solutions form a black precipitate upon saturation with hydrogen
sulphide, either al once, or upon the addition of an acid.
Mercuric iodide is partly decomposed when shaken with chlu-
rine-water ; the obtained filtrate, when rubbed upon bright copper,
coats it with a brilliant metallic lilm, and, when shaken with a
little chloroform, imparts to the latter a purple color.
Examination ;
Mercuric iodide, when heated to a temperature above 150** C.
(302° F.), should assume a unifi>rm yellow color, and, at a higher
temperature, should become completely volatilized ; with hot
alcohol it must alford a complete and colorless solution, without
acid reaction, from whicli, upon cooling, the larger portion of the
iodide is separated in a crystalline form ; ihe cold filtered solu-
tion, upon the subsequent addition of ammonia-water, should not
assume more than a brown coloration, and afford no precipitate.
When digested with cold or hot water, or with acetic acid of the
spec. grav. 1.040, no appreciable amount should be dissolved.
Soluble iodides or chlorides may be detected in the merouriu
iodide by digesting a little of the salt with water, filtering, and
testing the filtrate with argentic nitrate; a white or yellowish-
while turbidity or precipitate would indicate the presence of such
admixtures. '
Mercuric sulphide, red oxids of lead, or other fraudulent admix-
tures, will remain undissolved upon digesting the powder, cither
in solution of potassium iodide, or in twenty to twenty-five parta
of boiling alcohol. If a residue is left, it is washed with water,
and subsequently treated with warm nitric acid, and filtered; tbo
HYDRARGYRUM. 381
filtrate is slightly diluted, and tested with a few drops of diluted
sulphuric acid ; an ensuing white precipitate indicates lead. If a
rea residue remains, insoluble in nitric acid, it is tested by heat-
ing it upon platinum-foil to redness; if it is wholly volatile, mer-
curic sulphide is recognized, and, if a residue remains, fixed ad-
mixtures are indicated.
HTDRARGTRI lODIDUM VIRIDE.
HYDRARGYRUM lODATUM.
Or ten Iodide of Mercury, Protoiodide of Mercury. Mercuroun Iodide.
Qer. QuecksilberJodOr; Fr. Protoiodure de mercure ; 8p. Protoioduro
de mercurio.
Hgl; 326.3.
A heavy powder, of a dull -green or greenish -yellow color,
which suffers gradual decomposition and becomes brownish on
exposure to light, heat, and air. When heated in a dry tube
(Fig. 128, page 379), it begins, at 70° C. (158° F.), to assume a red
color, which increases in intensity until, at 200° C. (392° F.), it
acauires a deep garnet-red color; at 220^ C. (428° F.) it softens,
and melts at 290° C. (554° F.\ but begins to sublime, at 190°
C. (374° F.), and by slow sublimation forms small, transparent,
yellow crystals of the quadratic system, having the specific
gravity of 7.6; when quickly and strongly heated, it suffers a
partial decomposition into metallic mercury and mercuric iodide,
which do not again combine upon cooling.
Mercurous iodide is not quite insoluble in water, but wholly
insoluble in alcohol and in ether; it is decomposed by concen-
trated acids, by the alkaline hydrates, and also by boiling solu-
tions of the alkaline chlorides, bromides, and iodides, being
converted by the latter into mercuric iodide and metallic mer-
cury. When mercurous iodide is agitated in a little water to
which a few drops of ammonium sulphide have been added, the
liquid filtered, and the filtrate, after acidulating with hydro-
chloric acirl, mixed with a few drops of a solution of ferric
chloride and then agitated with a little chloroform, the latter will
acquire a purplish or violet-red color, due to the presence of free
iodine, which will appear still more distinct upon the subsequent
addition of a little water.
Examination:
Mercuric iodide may be detected when 1 gram of the powder is
agitated and digested with about 10 cubic centimeters of alcohol,
subsequently filtered, and the filtrate dropped into water, when
not more than a slight transient opalescence should be produced ;
and when 5 cubic centimeters of the filtrate are evaporated from
a white porcelain surface, not more than a faint red stain should
882 MANUAL OF OHBMICAL ANALYSTS.
remain behind ; neither should the filtrate afford more than a
very slight coloration or turbidity upon saturation with hydrogen
sulphide, otherwise the presence of an undue amount of biniodide
or mercuric salt is indicated.
Fixed imjfurilies will remain behind upon the complete vola-
tilization of the mercurous iodide in a dry tube; such would be
very likely to originate from either the mercury or the iodine,
and, if required, their nature may be determined by the methods
described on pages 388-390 and 395-396.
HTDRARGTRI OXIDUM FLAVUM.
HYDRARGYRUM OXYDATUM VIA HUMIDA PARATUM.
Tellow Oxide of Mercury, Precipitated Mercuric Oxide,
Ger. Gelbcs Quecksilberoxyd ; Fr. Oxyde de mcrcure jaune ; 8p. Prot6xido
de mercurio.
HgO; 215.7.
A heavy, orange-yellow i)owder, without crystalline structure
when seen under the microscope, permanent in the air, and
having a specific gravity of 11.3. It becomes darker on expo-
sure to the light, and assumes a red color on being heated; at a
higher temperature it is decomposed with the evolution of oxygen
and the separation of mercury, and is finally entirely volatilized.
It is more readily acted u[)on by reagents than the coarser red
oxide; the lattex remains unchanged when agitated with a warm
solution of oxalic acid, while the vellow oxide combines with
the oxalic acid, forming white mercuric oxalate ; when agitated
with a hot alcoholic solution of mercuric chloride, the yellow
oxide becomes at once black, in consequence of the formation of
mercuric oxychloride (IIgClj.21IgO), while the red oxide remains
unchanged for some time.
The chemical reactions of the precipitated yellow mercuric
oxide, and its deportment with reagents, correspond with those
of the red oxide.
HTDRARQTRI OXIDUM RUBRUM.
HYDRARGYRUM OXYDATUM.
Red Oxide of' Mercury, Red Precipitate. Mercuric Oxide,
Gcr. Rothes Quecksilberoxyd; Fr. Oxyde de mcrcure rouge ; Sp. Deut6xido
de mercurio.
IlgO; 215.7.
Heavy, coherent masses, consisting of bright, brick-red, crys-
talline scales, which, when finely pulverized, form a dull orange-
HYDRARGYRUM.
883
red powder, of a specific gravity of 11.136; when heated in a
dry tube, red mercuric oxide first changes to a dark cinnabar-red
color, and afterwards assumes a black tint, but regains its original
color on cooling; at temperatures above 400° C. (752° F.) it is
completely resolved into its constituents, and is entirely vola-
tilized below a red heat, while at a much lower temperature it
suflers a partial dissociation.
Mercuric oxide is slightly soluble in water, so that, when agi-
tated with boiling water, the filtrate possesses a decided metallic
taste, an alkaline reaction upon litmus, and affords with ammo-
nium sulphide a slight brown coloration; it is insoluble in pure
glycerin, in alcohol, ether, and chloroform, somewhat soluble in
saliva and in albuminous animal secretions, and entirely soluble
in strong and in somewhat diluted acids. The fixed alkaline and
earthy hydrates and alkaline carbonates produce in solutions of
mercuric oxide and its salts, when added in small quantity, a red-
dish-brown, when added in excess, a yellow precipitate ; ammonia-
water, a white one ; iodides (provided that the solution does not
contain a large excess of acid), when added in small quantity,
a yellowish, and in a larger quantity, a vermilion-red one, soluble
in an excess of the precipitant; stannous chloride, when added in
small quantity, gives a white, and, in excess, a gray precipitate.
When water saturated with hydrogen sulphide is gradually added
to the solution, or when the latter is slowly saturated with the
gas, a precipitate is formed which appears, according to the pro-
portion of the reagent, successively white, yellow, oranpe, reddish
Drown, and finally, with an excess of the precipitant, black.
884
MANUAL OF CHEMICAL ANALYSIS.
Examination :
Mercuric nitrate is indicated by the disengagement of red nitrous
vapors, when the oxide is heated in a dry test-tube. As a con-
firmatory test, and one permitting the detection of much smallei
quantities of nitrate, about 0.5 gram of the oxide is mixed with
10 drojKS of water, in a test-tube, then three times its volume of
concentrated sulphuric acid added, and to the mixture, after being
well agitated and subsequently allowed to repose, a saturatea
solution of ferrous sulphate is carefully added so as to form two
layers (Fig. 129) ; the occurrence of a dark brown zone at the line
of junction of the two liquids will confirm the presence of nitrate.
Admixtures, — A small portion of the oxide is gently heated
with about ten times its weight of dilute nitric acia, when com-
plete solution should take place ; if the oxide be very old, a slight
residue of reduced mercury might remain, which, when separated
and heated in a porcelain capsule, should wholly volatilize. If a
red or brown residue is left from the solution, an admixture of
Fio. 130.
mineral substances (brick dust, mercuric sulphide, or red oxide
of lead) would be indicated. If the nature of such a residue has
to be ascertained, a somewhat larger quantity may be obtained,
which, when washed and dried, maybe heated in a reducing-tube
HTDRARGTRUM. 885
(Fig. 130) ; vermilion volatilizes, forming a fine, red sublimate ;
red oxide of lead fuses, and exhibits, when cooled, a yellow vitri-
fied appearance, and dissolves, when boiled in concentrated nitric
acid diluted with an equal bulk of water, leaving behind silicious
mineral substances, if such be present. The solution of the
oxide in dilute nitric acid may also be tested with argentic ni-
trate, which should aftbrd no turbidity, thus establisliing the
absence oi chlorides.
HTDRARQTRI SUBNITRAS.
HYDRARGYRUM NITRICUM OXYDULATUM.
Subnitrate of Mercury. Mereurous Nitrate,
Ger. Salpetereaures Quecksilberoxydal ; Fr. Azolate mercurieax ;
Sp. Prutonitrato <le mercurio.
IIgNO,+ H,0; 279.7.
Colorless, transparent monoclinic tables or prisms,* containing
one molecule (6.5 per cent.) of water of crystallization, which is
lost on exposure to dry air or by standing over sulphuric acid ;
they u\e\t at 70^ 0.(158° F.), and when gradually heated in a dry
tul>e, emit yellow nitrous vapors, become yellow, then red, and
are finally resolved into metallic mercury ; the crystals become
grayisli-black when moistened with lime-water.
Mereurous nitrate is soluble in a small amount of warm water,
but, upon the addition of more water, it becomes decomposed,
with the separation of a yellow basic salt, HgNOj+HgOH, while
an acid nitrate remains in solution ; it is, however, entirely solu-
ble in water acidulated with nitric acid, forming a colorless solu-
tion, which, when rubbed on bright co[)per, coats it with a white,
metallic film, and, when largely diluted, yields a white precipi-
tate with hydrochloric acid, and a black one with ammonia or
lime-water.
Liquor Ilydrargyri Nitrici Oxydulnti of German pharmacy is a
solution of this salt, containing 10 per cent, of mereurous nitrate.
Examination :
Mercuric nitrate may be detected by completely precipitating
the solution of the salt in cold dilute nitric acid with diluted
hydrochloric acid, and testing the filtrate, in separate portions,
with hydrogen sulphide and with stannous chloride, and warm-
ing; a black precipitate with the first rejigent, and a gray one
with the second, would indicate mercuric nitrate.
* According to the proportion between the mercury and the nitric acid em-
ployed in tlie preparation, there is formed a normal or a basic mereurous nitrate,
which correspond in their chemical and therapeutical properties, except tliat,
when rubbed with a little sodium cliloride, the normal salt remains white, while
the basic salt gives a grayish -green mixture.
25
CHBUICAL ANALYSIS.
HTDRAROTRI BUBSULPHAB FLAVUB.
Tl'RPETHUM
Tetlote Subtulphaleof MBrevrg, Batie MereuHe Sulphalt. TurpeA Mintrol.
ngSO,+ 2HgO; 727.1.
A heavy, lemon yellow powder, of a crystalline structure when
seen under llie microscope, liaviug a specific gravity of 8.3, and
liosaessing an acrid taste. When heatttl in a dry inbe, il assutnea
a reddish-brown hue, but regains its original column cooling; at
a higher temperature it volatilizes without fusion, yielding a
white sublimate (mercuric sulphate) intermingled with gray me-
tallic mercury ; it is decomposed and entirely volatilized at a red
iieat, evolving vapors of mercury and of sulphurous acid.
Basic mercuric sulphate is almost insoluble in cold, and spar-
ingly soluble in hot, water, but soluble in diluted hydrochloric
and nitric acids, forming colorless solutions which, when diluted,
give a white precipilate with soluble barium salts, and which
otherwise, in their deportment with reagents, resemble the Holu-
tioiia of mercuric chloride and oxide (pages 374 and 383),
BTDRARaTRI BULPHIDUM RUBRDM.
HYDRAROYRUM SOLFURATUM RUBRUM. CINNABARI9.
JttA Sulphid* o/Mereurf, Cinnabar, Veri
ilion, Mm-eurie SfilpMdt,
HgS; 281.7.
Heavy masses, or cakes, of a specific gravity of 8.124, and of a
dull blackish-red color, and a brilliant crystalline texture, yielding a
red flireak when scratched with a knife, and a magnificent scarlet
powder, which becomes black when moistened with an ammonj-
ucal sobition of argentic nitrate. When heated to 250^ C. (482*^
P.), mcreuru! sulphide becomes brown, nt a higher temperature,
black, aikd, on cooling, reassumes its red color ; at a strong heat,
with exposure to the air, it is wholly dissipated, burning with a blu-
ish flame, and emitting the odor of sulphurous acid ; when gently
heated in a small glass tube, it softens, and sublimes without pre-
vious fusion, hut undergoes partial dissociation into a black mix-
ture of mercuric sulphide, mercury, and sulphur, with the evolu-
tion of a little sulphurcuN acid; when heated in closed vessels.
HTDRARQTRUM. 887
•
with exclusion of the air, it sublimes below a red heat, without
decomposition, in the form of beautiful red, crystalline crusts.
Mercuric sulphide is insoluble in the common solvents, nor is
it acted upon by officinal hydrochloric or nitric acid, or by alka-
line hydrates, at common temperatures; boiling concentrated sul-
phuric acid decomposes it, with the formation of mercuric sul
ph ate, attended by the separation of sulphur and the evolution of
sulphur dioxide; it is also soluble in concentrated hydriodic acid
in the cold, and in the dilute acid when warmed, with the evo-
lution of hydrogen sulphide; nitro-hydrochloric acid (aqua regia)
dissolves it readily, even in the cold, with the formation of mer-
curic chloride and sulphuric acid, and the separation of sulphur,
and yielding a colorless solution which, when diluted with water,
gives a white precipitate with barium chloride, coats metallic
copper with a film of mercury, and corresponds in its deportment
with reagents to solutions of mercuric salts (pages 874 and 383).
Examinaticm :
Oxides of Lead and Iron, — Such admixtures will be indicated by
the incomplete volatilization of the mercuric sulphide when strongly
heated in a small glass tube; their presence may be confirmed by
agitating a small portion of the salt, in a test-tube, with about
five times its weight of concentrated nitric acid ; the scarlet color
must remain unaltered, as change to a darker tint would indicate
red oxide of lead; the mixture is then gently heated bv immers-
ing the test-tube in hot water, and is subsequently diluted with
twice its volume of water, and filtered ; the filtrate should be
colorless; a yellowish appearance would indicate red basic plumbic
chromaUj or mercuric chromate (chromic cinnabar); it is then
tested in separate portions with hydrogen sulphide, with sulphuric
acid, and with potassium iodide, for lead ; another portion is tested
with potassium ferrocyanide for ferric oxide; if this be present,
the yellowish color of the nitric acid, agitated with the cinnabar,
may be due only to iron.
Chromates may be detected or confirmed bjr the occurrence of
red irritating fumes of chloro-chromic anhydride (CrO^CI^, when
a small portion of the mercuric sulphide is carefully mixed and
heated in a test-tube with a few small fragments of dry sodium
chloride and a few drops of concentrated sulphuric acid.
• Mercuric Iodide^ JRealfjar^ and Antimonic Cinnabar. — A portion
of the mercuric sulphide is agitated with about five times its
weipcht of a warm concentrated solution of potassium hydrate, the
liquid subsequently diluted with an equal volume of water, and
filtered ; the filtrate should be colorless, should cause neither a
coloration nor a turbidity when dropped into chlorine-water, and
should not afford a colored precipitate when dropped into a dilute
solution of plumbic acetate. A yellow or reddish coloration of
the chlorine-water would indicate mercuric iodide, and a black
precipitate with plumbic acetate, red arsenic sulphide (Realgar),
38»
HAXnAL OF CRBUICAL ANALYSI!
or antimotiic oxy-sulphide (Antimon'c CiiiDabar). If eitlier of
tlie latter two be indicated, the allcnline tilirnte will eive, upon
Bupereaturalion with hydrochloric acid, a yellow precipitate wlten
the 6r8t compoand is preseut, and an orange-red one with the
oecood.
HTDRAROTRUM.
Sltrciiry. Qvirk'ilrer.
Oer. QuEcksltbcr ; Fr. Mcrcure ; Sp. Slerciirio.
Hg; 199.7.
A silver-white and brillianlly lustrous metal, having a speciBc
gravity of lS.afl5 at 0° C- (32° F.) compared with water at 4" C.
(3».2°'F.), or 13,573 at lo** C. {69° F.). It is liquid at common
lemperntureH, and easily divisible into spherical globules, but
solidifies when cooled to —39.38° C. (—38.88° P.), forming al and
helow that temperaviire a ductile, malleable mas.'s, capable of
being cut with a knife, and cryBtanizing in octahedrons of the
regular system, which have a specific gravity of 14.39; it boils
at 807.25" C. (B75.05° F.), forming a transparent, colorless vapor,
but is volatile lo a perceptible extent at ordinary teuiperatures,
l)oth in a vacuum and in air. When pure, it is unalterable
Viy the action of the air at common temperatures, and remains
bright and brilliant.
Mercury is insoluble in the common solvents, in concentrated
bydroctilor c acid, and, at common temperatures, also in sulphuric
acid; but it is dissolved by the latter when boiled with il, and
is readily dissolved without residue by nitric acid, forming a
solution, which contains mercuric nitrate when heat is applied
and an excess of concentrated acid, and mercurous nitrate when
the metal is in excess or is noted ujion by cold and diluted nitric
acid,
Examinatloa :
Mercury amalgamates with many metals, and, lo a certain ex-
tent, without change of its appearance and properties; the most
common of such metallic impurities are lead and tin, and occa-
sionally zinc and bismuth; their presence in the comroerdal
metal is indicated by a dull, tarnished appearance, and a black,
powdery coating of the surfaces of the metal, and of the inside of
the vessels containing it, and by Icnd-gray streaks upon while
paper when a few globules of the metal are allowed to roll over it.
Such contamination may be ascerlaiited by agitating for a few
minutes a little of the mercury, in a strong bottle, with r moder-
ately dilute solution of ferric chloride (free from ferrous salt);
lifter subsidi[ig, the aqueous liquid is poured into a test-lube,
diluted with an equal volume ol water, and tested with a few
HVDRAHaVRCM.
88!)
drops of a aolmion of potassium ferricyanide; a blue turbidity
will indicate the above-mentiimed metallic impurities.
When tlieir nature lias to be determiuad, tlie foliowinz method
is practicable and simple, Abaut 20 grams of the metal, includ-
ing as raiioli of the powdery coating on the surfaces of the metal
Bud the bottle as can be collected, ia lieated and volatilized in a
small poruiiiain crucible, in a place where the vapors are readily
removed by draught; if a non-vulatile residue remains, it is
heated to redness. A small part of the remdne is then huated in
a test-tube with a few drop^ of concentrated hydrochloric acid;
the solution is decanted from the insohible residue, and, after the
addition of a little nitric acid or chlorine- water, one drop of solu-
tion of auric chloride is added; an ensuing purple or violet-red
turbidity would indicate lin.
The rest of the residue in the crucible is treated with warm con-
centrated nitric acid; if only partial solution takes place, and at the
same time a white precipitate is formed, this may be oxide of tin or
antimony; inordertodistin-
Ruish them, the precipitate Fio. 131.
IB separated from the acid
fiolution, washed with a lit-
tle water, and subsequently
heated upon charcoal be-
fore the blow-pipe; stavnous
oxide remains unchanged,
while nn(imoHi'coa:itZevolatil-
izes in white fumes, forming
B white concentric incrusta-
bon on the coal (Fig. 131).
The nitric acid solution --; ^:
' id diluted with an equal bulk
of water, and part of It ia tested with solution ol soHmm siilphiite;
a white preciuitate would indicate lead; another part is poured
into a large beaker full of water ; a white opalescence or turbidity
of the water indicates biamiith.
If lead be present, the rest of the nitric acid solution is satu-
rated and completely precipitated with hydrogen sulphide, and
allowed to stand in a corked test-tube for some hours ; it is then
filtered and supersaturated with ammonia-water; a white pre-
cipitate would indicate zinc.
If the precipitate is not quite white, and the lead has been
completely removed, it miglit be due to traces of iron, of which
metal, however, mercury can only contain traces, since it does
not amalgamate with it.
An efficient and satisfactory method for the purification ol
mercury, when contaminated with foreign metals, consists in
shaking it vigorously with an equal volume of a solution com-
posed of 5 grams of potassium bichromate and 5 grams of pure
390 MANUAL OF CHEMICAL ANALYSIS.
concenlrated siilphiiric acid in 1 liter of water. The metal is
reduced to small globulea, while a very small part of it ia con-
verted into red chromate. The agitation is continued until the
red powder has disappeared aod the aqueous solution has acquired
a pure green color, due to the chromium sulphate formed. By
means of a powerful current of water, which is passed into the
flask, the gray powder upon the surface of the mercury, which is
composed of the oxides of the metallic impurities, is washed away.
The process of oxidation is repeated onoe or twice, according tu
the degree of impurity, until gray powdery particles are no
longer formed, when the mercury is finally thoroughly washed
with distilled water until it remains perfectly clear.
HTDRAROTRUM AMlfONIATITU.
HYDRARGYRUM AMIDATO-BICHLORATUM. HYDRARGYRUM
AMMONIATUM BICHLORATUH. HYDRARGYRUM PR^ClPt-
TATUM ALBUM.
AmmoniaUd Mtrcary, While Peeeipitale. Mereuranuitoniiim Chloride.
Oer. Queckdlberamidnclilorid ; Fr. Merciire pr4cijiil£ blanc ; Sp. Preciiritftdn
III All CO.
NH,HgCl; 251.1.
White, i»ulvorulent, friable masse-s or a perfectly white, ino-
dorous powder, having a specific gravity of 6.7, and developing a
styptic taste when placed upon the tongue; it is decomposed and
entirely volatilized, without fusion, at temperatures below a red-
heat, forming calomel, ammonia, and nitrogen:
6SH,HgCl - 6HgCl + 4NH, + N,.
It becomes black in contact with hydrogen Bulphide, gray when
boiled with solution of stannous chloride, and pale yeliow, with
the evolution of ammonia, when heated with a solution of potas-
sium or sodium hydrate. When intimately mixed and triturated,
in its dry condition, with iotline, it becomes gradually decomposed
with slight deflagration, and with the formation of mercuric chlo-
ride and iodide, ammonium chloride, ammonia, and nitrogen gases;
the reaction is facilitated by the presence of a little water, but,
if alcohol be poured upon the mixture, a violent explosion en.sues.
Ammoniated mercury is insoluble in the common solvents, and
is gradually decomposed by prolonged washing with cold water,
more quickly by boiling water, into ammon urn chloride, and a
heavy, yellow, insoluble [)owder of hydraiod dimercummmomum
chloride [Hg/NH),C10]; it is readily and wliolly soluble with-
out effervescence in warm hydrochloric, nitric, and acetic acids,
forming colorless solutions, which, after dilution with water,
HTDRAROYRUM. 391
yield a white prec'pitate with a cold solution of potassium hy-
orate and with argentic nitrate, a black one with an excess of
hydrogen sulphide, and a red one with potassium iodide, and
which produce a black stain upon bright, metallic copper, coating
it, when rubbed thereon, with a brilliant metallic film.
Examination :
Mercuric chloride is detected by agitating a small portion of the
powder with about ten times its weight of diluted alcohol, filter-
ing, and testing the filtrate with hydrogen sulphide and with
potassium iodide ; a black precipitate with the first-named re-
agent, and a red one with the latter, soluble in an excess of the
precipitant, will indicate mercuric chloride.
Mercuroiis c/iloride may be detected by a black coloration of the
powder, when it is triturated with lime-water, or by dissolving a
small portion of the powder in warm diluted nitric acid ; if an
insoluble residue remains, it is washed by decantation, and, when
the water ceases to act on blue litmus-paper, the residue is agitated
with lime-water ; if mercurous chloride, it will become black.
Plumbic Carbonate and Chloride, and Calcium Carbonate,— Ga,T-
bonates are indicated by eflervescence of the powder with acids,
and plumbic chloride by its solubility in hot water (from which
it separates in a crystalline form upon cooling), and by its very
sparing solubilty in diluted hydrochloric and nitric acids. The
presence of lead and calcium salts may be further confirmed by
dissolving a portion of the powder in warm acetic acid, filtering,
and testing a little of the filtrate with sulphuric acid, when a
white precipitate will indicate lead, and, if the solution is not too
dilute, the possible presence also of calcium ; if a precipitate is
produced, the remaining portion of the acetic acid solution is com-
pletely saturated with hydrogen sulphide, subsequently filtered,
and the filtrate tested with ammonium oxalate, when a white pre-
cipitate will reveal the presence o{ calcium.
Zinc and maynesiiim oxides may be detected in the solution of
the powder in hydrochloric acid, after dilution with water, by
complete precipitation with hydrogen sulphide, and by subsequent
neutralization of the filtrate with ammonia- water, and the addition
of ammonium sulphide; a white prec pitate will indicate zinc;
after the complete precipitat on of the latter, and subsequent fil-
tration, the solution is boiled for a few minutes, and, after being
allowed to cool, is tested by the addition of a solution of sodium
phosphateand a little ammonia- water, when the formation of a white
crystalline precipitate will reveal the presence of magnesium.
These and all other non-volatile admixtures are also indicated bv
remaining behind when a few grains of the ammoniated mercury
are heated and volatilized, in a narrow, drv test-tube.
Mercurdiammonium chloride. {lUK^^KoGl^ or fusible white pre-
cipitate, will be indicated in this test by a partial or complete
392
MANUAL OF OIIGMICAL i
fusion of the pnwder, previous to its volatilization, provitied tbat
the amnioniateti mercury be free from any fixed fiiaible udmixtnre.
Starch. — An admixture of starcli is detected by the mioroaoope,
by the powder becoming oharred when strongly heated on plnli-
niim-foil, and also by a bUie coJoration, when a auiall portion of
ihe powder is triniraled, and subsequently heated to boiling, with
a little water, aud then tested with one drop of iodinized potas-
sium iodide.
HTOaCTAMIN^ SaLPHAS.
UVUSCVAMINLM SULFURICUM.
8atp\al» of Jlgi'tfj/uiitin
{C„H^O,),.E^O,; 676.
Small, golden-yellow, or yellowish- white scales or crystals, or a
yollowish- white, amorphous powder, deliquescent on exposure to
the air. When heated on pUtinuin-foil, the salt is deoompoaed
with the separation of carbon, and ia finally completely dissipated.
Hyoscyainine sulphate is very freely soluble in wHterand in aloO'
hoi. Its aqueous solution ia neutral in its action upon litmus,
possesses a bitter and acrid taste, and yields with solution of
barium chloride a white precipitate, insoluble in hydrochloric
acid; it is also precipitnled by most alkaloidal reagents, potossio-
meruuric iod<de, iodinized potassium iodide, picric acid, etc^ but
not by solution of platinic chloride ; with aur.c chloride, however,
it yields a precipitate, which, when recrystallized from boiling
water acidulated with hydrochloric acid, is dejMjited, on cooling,
in brilliant, lustrous, golden-yellow scales, without rendering the
liquid turbid (dist.Dution from atropine).
Ivdo/orm. Te
Ger. Jodoftii
I
■ Small, lemon-yeilow
I pearly lustre, a pcuulii
lODOFORMtTM.
lODOFORMIL'M.
■iodide <if Fiirmyl. Matheajil ladidt.
m ; Fr. lodoforroe ; Sp. lodolbnno.
CHI,; 392,8.
friable, six sided scales (Fig. 132), of a
-, penetrating, and persistent odor, and a
lODUM. 803
sweetish taste, and with a somewhat unctuous Fig. 132.
feel to the touch. Iodoform has a spec. grav.
of 2.0, is volatile at common temperatures,
and when heated in a dry tube, by immersing
it in boiling water, sublimes rapidly at about
95° C. (203® F.), solidifying in small scales, and
may be distilled with aqueous vapor without
decomposition; it fuses at 120^ C. (248° F.),
and IS decomposed above this temperature, or
when quickly heated, forming violet vapors,
and being resolved into iodine and hydriodic acid, with a residue
of carbon, which burns away at a stronger heat.
Iodoform is almost insoluble in water, glycerin, diluted acids,
and aqueous solutions of the alkaline and earthy hydrates, but is
soluble in 80 parts of cold, and 12 parts of boiling, alcohol, in 5.2
parts of ether, and readily in chloroform, carbon bisulphide,
benzol, benzin, and in the fixed and volatile oils. Concentrated
mineral acids, when cold, have no action on iodoform ; when
heated, it remains unchanged with hydrochloric acid, gives a red-
dish-brown solution with nitric acid, remaining limpid and brown
on dilution with water; it is freely dissolved, with a violet color,
by hot sulphuric acid; upon dilution, however, the color disap-
fears, and the iodoform is separated again in small yellow scales.
t is not acted upon by the aqueous solutions of the alkaline
hydrates, but their alcoholic solutions dissolve and decompose it,
forming alkaline iodide and formiate.
Examination :
Chlorides^ Iodides, and Sulphates, — A small portion of the iodo-
form is agitated with a little water for a few minutes, filtered, and
the filtrate, after acidulation with a few drops of nitric acid, tested
in separate portions with argentic nitrate and barium chloride; a
white, curdy precipitate with the first-named reagent will indi-
cate a contamination with chlorides or iodides, while a heavy
white precipitate with the latter will reveal the presence of sul-
phates.
IODX7M.
lODINUM. lODINIUM.
Iodine,
Ger. Jod ; Fr. lode ; Sp. lodo.
I; 126.6.
Heavy, brilliant, crystalline plates or scales, of an opaque
bloish-black appearance and imperfect metallic lustre, which
394
MANUAL OF CHEMICAL i
may be obtained from their solution in hydriodic acid in well
developed octabedral combinations of priams or pyramids of the
rhombic system (Fig. 133). Iodine possesses a
Fca. 133. peculiar oilor, less penetrating than, although
B similar to, that of chlorine and bromine. Its
specific gravity is 4.948 at IT"" C. (62.6° F.): it
melts at 114° C. (237.2= F.), and boils at a tem-
perature above 200^ C, (392° F.), giving rise lo
a vapor which, seen by transmitted white light,
possesses, when chemically pure, a splendid deep
blue color, but when mixed with air, a reddish-
violet color; it is, however, slowly volatile M
common temperatures. When heated in a dry tube (Fig. 134),
the vapors condense in the cooler parts of the tube to small,
brilliant crystals.
Fio. ia4.
Iodine is but sparingly soluble in water, requiring 45011 parts
of it at 15^ C. (59" F,), and imparting to it a faint brownish-yel-
low tinge. It is more soluble in glycerin, 100 parts of which
dissolve a little more than 1.5 parts of iodine. It is also soluble
to some extent in the aqueous solutions of certain salt-t, as for
instance of ammonium chloride and nitrate. Aqueous solutions
lODDM. 895
of hydriodic acid auJ of the alkaline iodides and bromides, dis-
solve iodine freely, as do also alcohol and ether, with a reddish-
brown color, benzol and chloroform with a violet-red, and carbon
bisnlphide with a rich purple. An aqueous solution of scxlium
hyposulphite dissolves iodine at first without color, and afterward
with a brownish-red tint.
Chloroform and carbon bisulphide, when shaken with an
aqueous solution of iodine, deprive it of most of the iodine, and
assume, when the fluids have separated, a more or less red color,
while the aqueous solution appears almost colorless.
Iodine forms with starch a deep-blue compound, which offers a
very delicate test for iodine in all solutions and in bodies which
contain it in the free state; the reaction is, however, impaired by
the presence of certain nitrogenized organic substances, such as
albumen, etc., as also by quinme and tannic acid.
Examinatioa :
Moisture is indicated in iodine by its adhering to the surface
of the bottles, and by a sticky coherence of the scales, as also by
the separation of globules of water when the iodine is dissolved
in chloroform or carbon bisulphide; its amount may be quanti-
tatively determined by triturating a weighed amount of the iodine
(about 2 grams) in a small porcelain capsule (the weight of which,
together with that of the pestle, has been previously deter-
mined) with about double its weight of mercury and a little
alcohol, sufficient to moisten the mixture, until complete combi-
nation is effected and free iodine can no longer be detected, either
by the eye or by its odor; the mixture of mercurous iodide and
mercury is then heated to 100° C. (212*^ F.) until its weight re-
mains constant, when the weight of the applied iodine and mer-
cury, minus the weight of the dried mixture, will represent the
amount of water contained in the iodine employed.
Iodine cyanide^ ICN, will be indicated by its exceedingly irri-
tating odor, and may be detected by agitating the iodine with a
little water for a few minutes, filtering, and adding to the filtrate
sufficient of a solution of potassium hydrate to produce a colorless
or nearly colorless solution ; a few drops of a solution of ferrous
sulphate and ferric chloride are then added, and subsequently
hydrochloric acid in slight excess, when the formation of a blue
precipitate, either at once or upon standing, will confirm the
presence of iodine cyanide.
Chlorine and Bromine, — A small portion of the iodine is dis-
solved in sulphurous acid, the colorless solution strongly super-
saturated with ammonia water, and subsequently completely
precipitated by argentic nitrate, and filtered ; the filtrate, upon
supersatu ration with nitric acid, should not become cloudy nor
yield a precipitate; a white precipitate will indicate the presence
of chlorine or bromine, as also of cyanogen, in case the latter
should have been confirmed by the preceding test.
3'*G MANVAL OF CHEMICAL ANALYSIS.
Fixfd and iiisoluble ndmixlnres (graphite, coal, carburet of!™ ,
mclallic oxides or sulpbidus) are detected by remaiuing beliind
upon the Toiatilizalion of a little of the iodine in a tcsl-mbc, or
upon solution of it in alcohol or in an aqueous solution of potas-
a iim hydrate or sodium hyposulpliile. If the nature of aach
admixtures has to be determined, the residue is collected and
washed uj>on a filter, and afterward treated with warm hydro-
ciiloritf acid diluted with an equal bulk of water, which dissolves
metallic oxides, and to some extent the sulphides, with the evolu-
litin of hydrogen sulphide. Ttie obtained solution may farther be
examined for metals, as described in the systematic course of
analysis (pages 61 to 61). The insoluble residue lufi from the
solution in hydrochloric acid is Ifvifiated (Fig. 135), whereby
graphite and carburet of iron may be separated and distinguisbm
from heavier mineral substances.
Estimation -.
About O.'i gram of the iixliue, accurately weighed, is dissolved,
ill a small flasic, iu about 10 cubic centiiiiet.ers of an aqueous ten
per cent, solution of potassium iodide. When complete solution
lias taken place, a standard solution of sodium hyposulphite
(page 94) is allowed to flow into the liquid from a burette, until
a tilight excess has been employed and complete decolorizalion of
the liquid is effected : a little mucilage of starch being then
added, the solution is subsequently titrated with a standard solu-
tion of iixline (page 93), until a permanent blue colpration is pro-
duced. The nuraljer of cubic centimeters of the sodium hypo-
sulphite solution employed, rainu^ that of the standard iodine
solution, when multiplied by its previously accurately determined
factor (page 'Jo), will represent the amount of pure iodine iu the
quantity applied for the lest, from which the percentage of impu-
rities may readily be calculated. By the employment of 0.6S3
L1QU0RES. 897
gram of iodine, dissolved in a solution of 1 gram of potassium
iodide in 25 cubic centimeters of water, and a precisely deci-
normal solution of sodium hyposulphite, the number of cubic
centimeters required of the latter, when multiplied by 2, will
represent, without further calculation, the exact percentage
amount of pure iodine in the specimen under examination.
LIQUOR AMMONn ACBTATI8.
LIQUOR AMMONII ACETICI
Solution of Ammonium Acetate, Spirit of Mindererui,
Oer. Essigsaure Ammoniumlosung; Fr. Acetate d^ammoniaque liquide ;
Sp. Solucion de acetato de amoninco.
A clear, colorless liquid, without empyreumatic odor, and of a
mild, saline taste; it contains about 7.6 per cent, of neutral am-
monium acetate, and has a spec. grav. of 1.022 (1.032-1.034:,
Pharm. German., corresponding to 15 per cent, of ammonium
acetate) ; it is wholly volatile upon evaporation, and emits the
odor of ammonia when heated with potassium hydrate, and that
of acetic acid when heated with suljhuric acid ; it assumes a red
color upon the addition of a trace of ferric chloride, and, upon
heating, the entire amount of iron is precipitated as a basic salt.
Examination :
Metallic impurities may be detected in the solution, after acidu-
lation with hydrochloric acid, by a dark coloration or precipitate
upon saturation with hydrogen sulphide, and, after filtration, if
necessary, and subsequent neutralization with ammonia-water,
by a turbidity or precipitate on the addition of ammonium
sulphide.
Sulphates and chlorides may be detected by a white turbidity,
when the liquid is acidulated with nitric acid and tested, in sepa-
rate portions, with barium nitrate for the former salts, and with
argentic nitrate for the latter.
LIQUOR ANTIMONII CHLORIDI.
LIQUOR 8TIBII CIILORATl. BUTYRUM ANTIMONII CHLORIDL
Solution of Trichloride of Antimony or of Antimoniovt Chloride.
Ger. Antimonclilortirlosung ; Fr. Chlorure d^nntimoine liquide ;
Sp. Solucion dc cloruro dc antimonio.
A dense, transparent, colorless or pale-yellow liquid, having a
specific gravity of about 1.470. Drof)ped into water, it gives a
white, bulky precipitate (antimonious chloride with antimonious
89S MANUAL OF CHEMICAL ANALYSIS.
oxide — Ah/uroih's Poicder), which is re-dissolved upon the addition
of potassium hydrate or tartaric acid. The solution with potassium
hydrate remains unchanged, or gives only a slight turbiditv, with
hydrogen sulphide, and yields a blnck precipitate with argentic
nitrate; while the solution with tartaric acid gives a copious
orange-red precipitate with hydrogen sulphide, and a white one
with argentic nitrate,
Examinatioa:
A Bmnli portion of the solution, when exposed to a moderate
heat iij a porcelain capsule, should be completely volatilized.
Antimonic chloride is detected in the solution, diluted with an
aqueous ten per cent, solution of tartaric acid, in order to avoid
precipitation, by the occurrence of a brown coloration on the
addition of a few drops of a solution of potaaaium iodide.
Iron and copper may be detected in the solution, after complete
precipitation with hot water and subsequent filtration, by the
addition of a few drops of solution of potassium ferrocyanide ; 8
blue coloration or precipitate will reveal the presence of iron, a
reddish-brown one, that of copper.
Lead will be indicated by the separation of a white precipitalo
when the solution of antimonious chloride is mixed with iwiec its
volume of alcohol, and may be further confirmed by the following
test: A small portion of the solution is diluted with water, and
subsequently sulntion of potassium hydrate added unlil the trans*
parency of tlie liquid is again restored ; it is then saturated with
hydrogen sulphide, when a black coloration will reveal the pres*
ence of lead, a white turbidity, that nfzi'nc.
Arsenic. — A portion of the solution is completely precipitated
by hot water, tillered, and the filtrate saluraied with hydrogen
sulphide. The ensuing precipitate, which may consist of arsenic
trisulphide, accompanied by a small amount of antimony, is cmI-
lected upon a filler, washed witn water, and digested with a con-
centrated solution of ammonium carbonate. The latter sulntioR
is then fillered, and, upon evaporation to dryness, will leave the
arsenic, if present, in the form of yellow arsenic trisulphide ; the
latter may be further examined, if required, by fusing it with a
mixture of sodium nitrate aud carbonate in a small porcelain cru-
cible, dissolving the fused mass in a little water, and testing it in
Marsh's apparatus (F.g, 20, p. 34), or it may be mixed with a
little exsiccated sodium carbonate and potassium cyanide, and
healed in a small reduction-lul>e (Fig. 64, p, TiS), when a mirror
of metallic arsenic will be produced.
Sulphuric and Nilric Acid«. — A portion of the solution is com-
pletely precipitated with water, tillered, and the tiltrute tested,
with barium chloride for sulphuric acid, and, in another portion,
by the addition of a drop of indigo solution and heating, lor nitre
acid ; the presence of the latter will be ind cated by ensuing de-
coloration of the liquid.
LIQUORBS. . 899
LIQUOR CALCIS.
AQUA CALCIS. AQUA CALCARI^.
Lime- WaUr. Solution of Calcium EydraU,
Ger. Kalkwasser ; Fr. Eau de chanx ; Sp. Agua de cal.
A clear, colorless, and odorless liquid, consisting of a saturated
solution of calcium hydrate, and having, at 15° C. (59° F.), a spe-
cific gravity of 1.0015. It possesses a saline and feebly caustic
taste and an alkaline reaction, and contains in solution about
0.128 per cent, of calcium oxide, or 0.17 per cent, of calcium
hydrate. Lime-water readily absorbs carbcmic acid from the air,
forming on its surface a pellicle consisting of minute plates of cal-
cium carbonate; its alkaline reaction disappears when an excess
of carbonic acid gas has been passed through it, and the excess
has been expelled afterward by boiling.
Lime-water affords no precipitate with sulphuric acid (distinc-
tion from solution of barium or strontium hydrate), but it forms
white precipitates with carbonic, boracic, phosphoric, arsenious
and arsenic, oxalic, and tartaric acids and their salts, and precipi-
tates the solutions of those salts whose metallic oxides or hydrates
are insoluble in water.
The quality of lime-water is best ascertained by its property,
when warmed in a test-tube, of separating nearly half the quan-
tity of calcium hydrate in minute nexagonal prisms; upon cool-
ing, the crystals red ssolve, and the water becomes perfectly clear
again. The presence or absence of alkalies (potassium or sodium
hydrate) or alkaline carbonates may be determined by saturating
the lime-water with carbonic acid gas, and subsequently heating
to boiling; the filtered liquid must be neutral to test-paper ; an
alkaline reaction would indicate the above-mentioned impurities.
LIQUOR FfiRRI ACBTATZ8.
LIQUOR FERRI ACETIC!.*
Solution of Acetate of Iron, Solution of Ferric Acetate,
Ger. Essigsaure Eisenoxydldsung ; Fr. Liqueur d'ac^tate de fer ; Sp. Acctato
de hierro liquido.
A transparent, dark reddish-brown liquid, containing 33 per
cent, of anhydrous ferric acetate, Fe3(CjH,0j^^, corresponding to
♦ Liquor Ferri Acetici, of the Pliarmacopoea Gernianica, is prepared by tlie
precipitation of 10 parts of solution of ferric cliloride, of 1.28(» to 1.282 spec grav.,
diluted with 50 parts of water, witli a mixture of 10 parts of ammonia-water.
spec gray. 960, and 200 parts of water ; the precipitate is collected and washed
400
MANUAL OF CHEMICAL ANALYSIS.
7.93 per cent, of metallic iron, and having a sj^ec. gray, of 1.180
at 15° C. — oS"* F. (1.081 to 1.083, Pharm. Germ., corresponding to
from 4,5 to 5 per cent, of metallic iron, or from 18.7 to 20.8 per
cent, of anhydrous ferric acetate); it has a faint odor of auetic
acid, which becomes more evident upon warming; this may
also be recognized by the formation of white vnpors, when a glass
rod, moistened with ammonia-water, is held over the linuid.
Solution of ferric acetate yields with ammonia-water a redoiph-
brown precipitate, and with potaseium ferrocyanide, a deep-blue
one; and, when largely diluted with water, should afford with a
few drops ol a freshly prepared solution of potassium ferricyanide
a pure greenish -brown eoloration, without a blue tint (evidence of
the absence of ferrous salts). If the solnlion be healed to boil-
ing, it becomes turbid, in consequence of the separation of insoluble
basic ferric acetate.
EsaTninatiDn;
A smiill portion of the liquid is diluted with twice ita volume
of water, and the iron completely precipitated by the addition of
a considerable excess ot' ammonia- water and heating to boiling:
the filtrate must be wholly volatile when a few dro]>8 of it. are
evaporated in a porcelain capsule or on plaiinum-foil ; a vised
residue, which becomes charred at a stronger heat, with the evo-
lution of va])ors having the odor of caramel, would indicate sui/ar
oT fruit acida, which, wiien present in considerable quantities, pre-
vent the complete precipitation of the ferric solution by ammonia-
water. A bluish tint of the filtrate would indicate copper, whiob,
with other metallic impurities, may be further determined by
saturating it with hydrogen sulphide, both before and after acida-
lation with hydroehlorio aeid.
Hytlrochloric and Sulp/itirtc Actib. — A portion of the solution,
diluted with an equal volume of water, is heated until the iron
lias become completely precipitated, and filtered; the filtrate, after
acidulation with nitric acid, is then tested, in separnte portions,
with argentic nitrate for hydrochloric acid, and with barium nitrate
or chloride for sulphuric acid. The verification of the proper
amount of iron in the solution may be accomplished by refere.no«
to its specilic gravity, and by evaporating 10 grams of the solu-
tion, to which a few drops of nilric acid have been added, to
dryness, in a amall platinum capsule, and subsequently igniting
at a red heal; the residue of ferr.c oxide thus obtained should
weigh 1.13 grams,
upon a flnnnel nr f«lt flltrr. and aflprward inhjrclcd to strong pressure. Tli«
Htrt, liiimiil ninu) nf I't-iric iiydralp U llioi IrnuFlerrrd Xnn ShbIi, t> pitris of dilate
allelic nciil, spec grnv. 1 ,041, lidded. »iid tlif iiiixlure nllowtd In stand in a cool
plnc, Willi freqitpiit RgitHllnli. unlil tlit prcclpltnle tins liecnine enllrrl; dU-
wilveil, fir liul A slij^lil iOBMlulik rt'tildiit rvmiiinB ; bo iiiiirli wtitiT h tlitn udded
llmt the BDlinlim shall Imve the >prc. trritv. 1.081 to l.U8:t,
LIQUORBS. 401
LIQUOR FBRRI CHLORIDI. •
LIQUOR FERRI SESQUICHLORATL*
Solution of Chloride or Perchlorids of Iron. Solution of Ferric Chloride,
m
Ger. Eisenchloridlosung ; Fr. Clilorure de fer liquide ; Sp. Sohicion
de percloruro de hierro.
A dark reddish-brown liquid, having a faint odor of hydro-
chloric acid, an acid, strongly styptic taste, and an acid reaction.
Its specific gravity is 1.405 at 15° C. (59° F.), and it contains
37.8 per cent, of anhydrous ferric chloride. It is miscible in all
proportions with alcohol, water, *and glycerin, and the solution
after admixture with alcohol is not rendered turbid on the sub-
sequent addition of ether. The diluted aqueous solution affords
a brownish-red precipitate on the addition of ammonia-water, a
blue one with potassium ferrocyanide, and a white one, insoluble
in nitric acid, with solution of argentic nitrate.
Examination :
Ferric oxy-chhride may be detected by the occurrence of a tur-
bidity, when 3 parts of the solution are diluted with water to the
measure of 100 parts, and subsequently heated to boiling.
Ferrous chloride may be recognized in the diluted solution by
an ensuing blue coloration or preui|)itate on the addition of a
freshly prepared solution of potassium ferricyanide.
A portion of the solution, diluted with an equal volume of
water, is completely precipitated by an excess of ammonia- water,
filtered, and the filtrate divided into four portions, which may be
employed for the following tests:
Fixed alkalies or alkaline salts may be detected by a non- vola-
tile residue upon evaporating a portion of the filtrate to dryness,
and subsequent ignition at a gentle heat.
Metallic Impurities, — Copper will be indicated by a blue color
of the ammoniacal liquid; and zinc may be detected by a white
tifrbidity or precipitate on the addition of a few drops of ammo-
nium sulphide, or, after acidulation with hydrochloric acid, by a
white precipitate on the addition of solution of potassium ferro-
cyanide.
Sulphuric acid will be indicated in the filtrate, after supersatu-
ration with nitric acid, by a white precipitate on the addition of
solution of barium chloride.
Nitric acid may be detected in another portion of the filtrate,
concentrated by evaporation, if necessary, by the addition of a
slight excess of concentrated sulphuric acid, a drop of indigo solu-
tion, and gently heating; ensuing decoloration of the liquid will
♦ Liquor Ferri sesquichlomti, of the Pharmacopoca Germanica, lias the spec.
grav. 1.280 to 1.282, and contains 29 per cent, of anliydrous ferric chloride,
corresponding to 10 per cent, of metallic iron.
26
402 XA!rCAL OF CHBXrCAL ANALYSIS.
reveal rlie presence of nitric aci<I. Or, to a portion of the liquid,
mixe<l witii an. excesfi of ci^ncentratLMi sulphuric acid, a crystal
ot' tern JUS su!pliute is adiletl, or a onoenrrated solution of the
larrer s.-ilr is carefully pori red upnn the -iqnid. so as to form two
layers (Fi^. i'l\K p. ^-si), when a dark coloration of the crystal,
or a hrown or vir»iet-coloretl zone at the line of contact of the two
liqui«]s, will likewise indicate the presence i>f nitric acid.
EBtimation :
The determination of the strength «)f liquor fcrri chloridi may
be readi'.y accomplished, in a<ldition to the veritication of the
pr»)per speiritic gravity, by diluting lo irrams of the S4>lution with
an eq'ial volume of water, heating to the b«.>i ling- point, and com-
pletely pretMj'itating the inm by the n« Id it ion of ammonia- water
in exfoss. The ['retripitate »>f ferric livdrate, when collecteil on
a filter, thoroughly washetl. drie«1, and isznited, should leave a
residue of ferric oxide weiiihiu'j l.S*> u'ranis.
LIQUOR FERRI CITRATIS.
LIQUOR FERRI CITRICI.
A -iMrlc brown, transparent liqui'l, withv^u o«Jor. and having a
-/.•^'■iit'.y fiMTiiLrin-'iis raste. ;ind an acid rea^.-tion. It has a s|:>ec.
;.r;iv. -■:' l.-Oo, jiiid <'i»iit:i:iis a'^'nr :'..'»..") [.or cenr. of anhydrous
terric c trate. Fey L\II,< )^),. c«»rres{H)iiding to S.l per cent, of lue-
t;i'.!ic ir-'p.. Wiieii tue st>!ut •.•:! is c-'U'-'enr rated by evaporation,
;'.r :t ge::t!o l.eat, and spread uj'on plates ot irlass. it forms, upon
drviiiLT, trai.si-arent, iraruet-re«l scales. wli'L-h are eas Iv detached
fr«>ni tlie ^la.-.-. If ion parts of tiiC solutiiM; bo thus treated, from
4o to 44 parr.- of tiie scalt'd salt sli«»uM bo obtained, wh ch, when
4''»nipleTe!y ::!••: licraTed at a stroi.g hear. :u a small [porcelain cru-
<■!■/»-. -i.','u!d leave a rc-idue of iV-rric oXL-ie. arnoiuuinj; to abolit
1 1 part-.
So!;:.'-:: '»f f«irr:c citraii' is not pre«r!pitatr;d, but is rendereil
sonie\^ ;. tt <iarker. <.»ri t:i»- a-iditiori nt ai!:ni"!i:a-water : and vields,
with .-••Jirioii ol p'Ta.-siinii t'errocyai.iile. a I'luish-izreen color or
preeip.latr*. wli.eh !sreiideri*d dark i'JKM'U the subsequent add.tion
of liydr«K:h!or;e ae;«i. It" the >«.)!ut"oM be b«»'!cd with an excess
(tC >o!nTion ot potassium hydrate, a red«lishd)rown precipitate of
ferric i.ydrate is ppMbieed; the tiltrate therefrom, after concentra-
tion ai:d beiig allowed to cool, is precipitated by solution of cal-
cium ehloridt?. and the tiltrate from tlie latter ]»recipitate, when
heatefl to ijoiliiig. yields a white, granular precipitate of calcium
citrate.
LIQUORBS. 408
LIQUOR FERRI ET QUININJB CITRATIS.
LIQUOR FERRI CITRICI CUM CHINING CITRfCO.
Solution of Citrate of Iron and Quinine. Solution of Ferric and Quinine
Citrates,
A dark greenish -yellow to yellowish brown liauid, transparent
when diluted or in thin layers, without odor, ana having a bitter
and mildly ferruginous taste, and a slightly acid reaction. It
contains 6 per cent, of quinine, which has been dried at 100° C.
(212^ F.).
If the 3olution be supersaturated with a slight excess of ammo-
nia-water, a white, curdy precipitate is produced, which corre-
sponds to the reactions and tests of quinine, and the liquid assumes
a somewhat darker color. If the mixture be then filtered, and a
portion of the filtrate slightly supersaturated with hydrochloric
acid, a deep blue precipitate is produced. Another ])ortion of the
filtrate, when heated with an excess of solution of potassium
hydrate, yields a reddish-brown precipitate of ferric hydrate; the
filtrate therefrom, after concentration and being allowed to cool,
is precipitated by solution of calcium chloride, and the filtrate
from the latter precipitate, when heated to boiling, yields a white
granular precipitate of calcium citrate.
On heating the solution with a strong solution of potassium
hydrate, vapors of ammonia are evolved.
Estimation of the Quinine in Solution of Citrate of Iron and Qui-
nine:
Eight grams of the solution, contained in a closely fitting, glass-
stoppered bottle or flask, are diluted with water to the measure of
30 cubic centimeters, an aqueous solution of 0.5 gram of tartaric
acid added, and subsequently solution of sodium or potassium hy-
drate, in slight excess. The mixture is then agitated with four
successive portions of chloroform, of about 15 cubic centimeters
e^ch, the chloroformic layers being removed by means of a glass
separating funnel, afterward mixed, and allowed to evaporate spon-
taneouslv in a weighed glass or porcelain capsule, and linallv dried
at 100° "0.(212"^ F.), until of constant weight. The residue of
quinine thus obtained should weigh 0.48 gram, corresponding to
6 per cent, of the weight of solution employed.
This hooh is the pTopi * .
COOPER MEDICAL COIJ..- •
8AN FRANCISCO. OAL.
aPfl is not to he remold / -m ^-'
V- '• lit • " • '•'*
l« l' t •
404 MANUAL OF CHEMICAL ANALYSIS.
LIQUOR FERRI NITRATI8.
LIQUOir FERRI NITRICI. LIQUOR FERRI PERNITRATIS.
Solution of Nitrate or Pernitrate of Iron. Solution of Ferric NitrnU\
Ger. Eisenoxydnitratlosung ; Fr. Solution (Vnzotate de fer;
!Sp. Solucion de pernitrato de bierro.
A transparent amber-colored or reddish yellow liquid, having
an acid, strongly styptic taste, and an acid reaction. Its specific
gravity is l.OoO at l»o° C. (59° F.), and it contains about 6 per
cent, of anhydrous ferric nitrate. Diluted with water, it gives a
deep blue precipitate with potassiuui ferrocyanide, but none with
potassium ferricyanide, and yields a reddish -brown precipitate
with ammonia-water; when a few drops of a concentrated solu-
tion of ferrous sulphate are added to a little of the solution of
ferric nitrate, and the mixture is carefully transferred upon con-
centrated sulphuric acid (Fig. 129, j). 388), a dark zone, indicating
nitric acid, will ensue upcm the line of contact between the two
liquids.
Examination :
To a portion of the solution ammonia- water in slight excess is
added, the liquid filtered from the precipitate of ferric hydrate,
and the filtrate employed for the following tests :
MetnlUc Impurities, — Copper will be indicated by a blue color
of the aminoniacal liquid ; and zinc may be detected by a white
turbidity or preci[)itate on the addition of a few drops of ammo-
nium sulphide, or, after acidulating with hydrochloric acid, by a
white ])recipitatc when tested with {)otassium ferrocyanide.
Hydrochloric and sulphuric acids may be detected in another
portion of the filtrate, supersaturated with nitric acid, when
tested respectively with argentic nitrate and barium nitrate or
chloride.
Estimation :
In addition to the verification of the proper specific gravity,
the strength of liquor ferri nitratis may readily be determined by
;om])letely ])rccipitating 100 grams of the solution with ammo-
nia-water. The precipitate of ferric hydrate, when collected on
a filter, thoroughly washed, dried, and ignited, should leave a
residue of ferric oxide weighing 2 grams.
(
LIQU0RB8. 405
LIQUOR FERRI 8ULPHATI8.
LIQUOR FERRI SULFURICI OXYDATI.
Solution of Persulphate of Iron, Solution of Ferric Sulphate.
Gcr. Eisenoxydsulfatlusung ; Fr. Liqueur de pereulfate de fer ; Sp. Solucion
de pereulfato de bierro.
The U. S. Pharmacopoeia has two solutions of ferric sulphate,
Liquor Ferri iSnlsril/i/iatis, having a spec. grav. of 1.555, and
Liquor Ferri TersuJi^hatis, having a spec. grav. of 1.320. The
former is a solution of basic ferric sulphate [Fe^O(SOJJ, contain-
ing 43.7 per cent, of the salt; the latter, a solution of normal
ferric sulphate, FeiSO^)^ containing 28.7 per cent, of the salt.*
The Liquor Ferri Persiclphatis of the British Pharmacopoeia has
the spec. grav. of 1.441, and that of the Pharmacopoea Germanica
a spec. grav. of 1.428 to 1.430.
They all are transparent, red or reddish-brown liquids, without
odor, of an astringent, metallic taste, and miscible in all propor-
tions, with water, alcohol, and glycerin, without decomposition.
A few drops of either of them, added to water, form a mixture
in which potassium ferricyanide ])roduces no reaction, but ferro-
cyanide gives a dark-blue precipitate, ammonia- water a bulky,
reddish-brown one, and barium chloride a white one, the latter
insoluble in hydrochloric acid.
Examination :
Copper and Zinc, — A small portion of either of the above solu-
tions of ferric sulphate is mixed with about an equal volume of
water, heated to boiling, and the iron completely precipitated by
the addition of ammonia- water in excess, and filtered. The filtrate
will appear bluish, if copp>er be present, and should be entirely
volatilized when heated upon platinum-foil ; a fixed residue would
indicate alkaline^ earthy, or metallic impurities. Part of the filtrate
is then saturated with hydrogen sulphide, an ensuing white i)re-
cipitate would indicate zinc, and a dark one, insoluble upon
supersaturation with hydrochloric acid, copper.
Nitric acid and nitrates may be detected in a portion of the
filtrate of the preceding test, by supersaturating it with concen-
trated sulphuric acid, and by subsequently adding one drop of a
solution of potassium permanganate, or indigo solution, and gently
warming; ensuing decoloration will indicate nitric acid or nitrates.
Estimation :
In addition to the verification of the proj)er specific gravity, the
strength of solutions of ferric sulphate may be readily determined
♦ The two preparations may readily be distinguished by slowly mixing, in
a beaker, 2 volumes of the solution with 1 volume of concentrated sulphuric
acid ; the tiqnor ferri subsulpliatis separates a solid wiiite mass on standing,
while the liquor ferri tersuiphatis retains its fluidity.
406 MANUAL OF CHEMICAL ANALYSIS.
by completely precipitating 10 grams of the solution with an ex-
cess of ammonia-water, collecting the jirecipitate of ferric hydrate
on a filter, washing it thoroughly with water, and, after drying,
igniting in a porcelain crucible at a red heat. Ten grams of
li<iaor ferri subsulphatis should thus afford a residue of ferric
oxide weighing 1.1)88 grams; and the same amount of liquor ferri
tersulphatis, a residue of ferric oxide weighing 1.1^7 grams.
LIQUOR HTDRARGTRI NITRATI8.
LIQUOR HYDRARGYRI NITRICI OX YD ATI.
Solution of Nitrate or Pernitrate of Mercury. Solution of Mercuric Nitrate.
Ger. Salpctersaure QiiPcksUberoxydlosiing ; Fr. Nitrate de mercure liquide ;
Sp. Soluciou de pernitrato de mercurio.
A dense, transparent, nearly colorless, acid liquid, having a
faint odor of nitric acid, and, even when diluted, a very acid,
caustic and metallic taste. It has a specific gravity of 2.100 at
15° C. (59° F.), when prepared accord. ng to the U. S. Pharma-
copoeia, and of 2.24:6, when prepared according to the British
Pharmacopoeia, containing, in the first instance, about 50 per
cent, of mercuric nitrate in solution.
When a few drops of the liquid are evaporated at a gentle lieat,
upon platinum foil, they leave a white residue, which, upon in-
creased heat, becomes successively yellow, red, and brown, and is
finally wholly dissipated. The solution remains limpid on the addi-
tion of wattn* or of diluted hydrochloric acid (evidence of the ab-
sence of mercurous nitrate): it gives a dull yellow precipitate with
an excess of the fixed alkaline and earthy hydrates, a white one
with ammonia- water, a bright red one with potassium iodide,
soluble in an excess of the reairent, and a black one with an
excess of hydrogen sulphide; it deposits a brilliant metallic ct)at-
ing on bri^dit copper, and shares, in its deportment with reagents,
the gei;eral characteristics of mercuric salts, as described under
mercuric chloride and oxi<le (pages o74 and 3><»^). It causes a
crystal of ferrous sulphate, dropped into it, as well as the liquid
around the salt, \o assume a (]cei>-brown color.
When diluted with about ten times its yolume of water, it should
not giye a turbidity when tested, in separate portions, with a few
drops of solutions of argentic and of barium nitrates (absence of
chlorides and siil/Jtates),
LIQUORES. 407
LIQUOR PLUMBI SUBACETATIS.
LIQUOR PLUMBI SUBACETICL ACETUM PLUMBICUM.
Solution of Sabacetate of Lead, Solution of Triplumbic Acetate.
Ger. Bleiossig ; Fr. Sous-acetate de plomb liquide ;
Sp. Subacetato de plomo Hquido.
A dense, clear, colorless liquid, of 1.228 spec. grav. (1.235-
1.240 Pharmacopoea Germaiiica), having an alkaline reaction and
a sweet, astringent taste, and becoming turbid by absorption of
atmospheric carbonic acid, and by dilution with water containing
carbonates, sulphates, or carbonic acid. It is precipitated,
whether diluted with water or not, by the alkaline and alkaline-
earthy hydrates and carbonates, by sulphuric, hydrochloric,
oxalic, tannic, and otlier acids and their salts, and by almost all
neutral salts; it forms white, opaque, insoluble compounds with
vegetable gums, mucilages, and extracts, and with vegetable and
albuminous substances.
Liquor plumbi subacetatis gives a yellow, precipitate with
potassium iodide, and a black one with hv^drogen sulphide; it
forms an opa([ue, white jelly when mixed with mucilage of gum;
it may be recogirtzed as containing an acetate, by evolving the
odor of acetic acid, when heated with a few drops of sulphuric
acid, and by affording a deep-red color, accompanied by the sepa-
ration of plumbic chloride, on the addition of a few drops of a
dilute solution of ferric chloride.
Traces of co])per are indicated by a faint greenish color of the
liquid, and may be further recognized by a bluish coloration of
the filtrate, when a little of the liquor plumbi subacetatis is
mixed with an excess of ammonia- water.
Estimation :
13.7 grams of the solution should require for complete ]>recipi-
tation 25 cubic centimeters of normal solution of oxalic acid
(page 82), corresponding to 25 per cent, of basic j)lumbic acetate.
By the employment of other quantities of the solution than that
above mentioned, the calculation may also readily be made, with
the consideration that 1 cubic centimeter of normal oxalic acid
solution corresponds to 0.13(375 gram of basic plumbic acetate,
Pb,0(C.H,0.),.
408 MANUAL OF CnBMICAL ANALYSIS.
LIQUOR POT AS 8 JB.
LIQUOR POTASSII HYDRICI. LIQUOR KALII CAUSTICI.
Solution of Potasm, Solution of Potassium Ilydrate,
Ger. Kalilaugc ; Fr. Liqueur de potasse ; Sp. Solucion de potasa.
A transparent, colorless, limpid liquid, without odor, of an
extremely acrid and caustic taste and strongly alkaline reaction,
and having a soapy feel when rubbed between the fingers. It
has a destructive action on many vegetable and animal sub-
stances, is a j)Owerful solvent for many organic and mineral com-
pounds, and readilv absorbs carbonic acid gas by exposure to the
air ; when dropped into a concentrated solution of tartaric acid,
a white crystalline precipitate is produced, which is re-dissolved
by an excess of the alkali. The specific gravity of the solution
is 1.086 at 15^ C. (59^ F.), and it contains about 5 per cent, of
potassium hydrate.*
Examination :
Carhonate is indicated bv eflcrvesceucc or by the formation of
gas-bubbles, when the liquor potassa3 is added to an excess of
hydrochloric or nitric acid ; it may also be detected by the for-
mation of a white precipitate when a little of tke liquor potassae
is mixed with an equal volume of water, and is then added to
lime-water.
SfnUnm hydrate may be detected by the following method,
which is based upon the solubility of sodium bitartrate, and the
insolubility of potassium bitartrate, in alcohol. A weighed por-
tion of the liquor potassio is exactly neutralized with tartaric
acid, and to the solution as much tartaric acid subsequently added
as was previously required for neutralization. Alcohol is then
added until a ]>recipitate ceases to be produced, and the liquid
filtered. The filtrate, which will contain the sodium in the form
of bitartrate, will deposit the latter upon evaporation, and, upon
ignition, will leave a black, strongly alkaline residue of carbon
and sodium carbonate. If this residue be dissolved in water, the
solution filtered, neutralized with dilute nitric acid, and coucen-
tratc<l bv evaporation, rhonibohedral crystals of sodium nitrate
may be obtiiined, which impart an intense yellow color to the
non-luminous (lame.
Pt}tus.v'nm chloridf, suJpJtHle, and hi/pnsvlphile may be detected
by dro]»i>ing a little of the liquor potassie into diluted solution of
argentic nitrate ; a gravish-l)rown precipitate will be produced,
which, however, should be completely soluble upon the addition
of nitric acid in excess; if the precipitate does not wholly dis
* Licpior Kftlii caustici, of the Pliarmacopoea Germanica, has a spec, i^rav. of
from 1.112 to 1.140, ami contains about 13 per cent, of potassium hydrate.
LIQUORBS. 409
solve, and leaves behind a white residue, chlcride is indicated ;
when the residue is black, sulphide or hyposulphite.
Sulphate^ Silicate, and Alumina. — A little of the liquor potassjB
is slightly supersaturated with diluted nitric acid; part of the
solution is tested with barium nitrate for sulphate ; another part
may also be tested with argentic nitrate for chloride ; the rest of
the solution is evaporated, in a porcelain capsule, to dryness;
the remaining salt must yield a limpid solution with water; a
white insoluble residue would indicate silicate; the solution,
when necessary, is filtered, and then tested by the addition of a
little ammonium chloride and ammonia-water for alumina, which,
when present, will afford a white flocculent precipitate.
Calcium salts may be detected, in the diluted liquor potassai,
previously neutralized with nitric acid, by a white precipitate
with ammonium oxalate, or with sodium carbonate.
Metallic impurities are indicated by a dart coloration or tur-
bidity when the liquor potassae is saturated with hydrogen sul-
phide, either before or after supersaturation with hydrochloric
acid.
Estimation :
The amount of pure potassium ^lydrate contained in liquor
potassas may readily be determined volumetrically. About 20
grams of the liquid are accurately weighed in a beaker or small
flask, a few drops of litmus solution added, and subsequently
a standard solution of oxalic or sulphuric acid (page 82) allowed
to flow into the liquid from a burette until, with constant stir-
ring, the blue tint of the liquid is just changed to a cherry-red.
From the number of cubic centimeters of the acid solution thus
required for exact neutralization, the amount of pure potassium
hydrate may be calculated: one cubic centimeter of normal acid
corresponding to 0.056 gram of potassium hydrate, KIIO. By
the employment of 28 grains of the officinal liquor potassae, not
less than 25 cubic centimeters of the normal acid solution should
be required for exact neutralization, indicating a strength of at
least 5 per cent, of potassium hydrate.
If the liquor potassae contain carbonate, the amount of carbon
dioxide contained in a weighed portion of the solution must be
determined, as described on pages 85-86. For 1 part of carbon
dioxide, CO,, 2.545 parts of potassium hydrate, KHO, are de-
ducted from the amount volumetrically indicated, and the balance
then calculated as pure potassium hydrate.
Tahlg of the qiiaiUili/ by wrigkt af Pofatiiiim Oxide and Ifi/dritif ron-
(ii'Hfd in lOi) pnrU lit/ mn'g/il of solution (^Liquor Potattit) uf difftrtnt
tpeeijie gravities {Gerltie/i).
Teraperaiure IW C. (58=1 F.).
Pwol.
ntK^a
BiwjSo
Bp«lll«
ufK,o
Sp»l<le
Sp»l<0
Per Hi.
Bptelli
ep*cito
KHO.
fo7i%
r^Ka
KHO.
sra
r^;vin>.
?:rK%
finx
1.010
1.000
21
1.331
1.188
41
i.nas
l.tas
1.030
1.017
33
1.34-3
1.188
43
1.838
i.«m
1.030
1,03.1
3!i
1.3.18
1.300
43
1..554
1.450
1.33B
1.0:«
24
1,370
1.320
44
1.570
t.463
1.048
1.041
!5
1.385
1.330
4.1
I..W4
1.474
1.0.W
1.040
38
1.300
1.241
48
l.fllM)
1.488
1.0«8
l.o:.8
37
1.313
i.a.-.a
47
1.015
1.498
1.078
i.On^
38
1.336
1.304
' 48
1.630
1..11I
1.080
i.n?*
38
1.S40
1.!t70
48
1.64.1
1.537
1.081)
1.083
»0
l.S.W
1.38S
50
1.660
1..WI9
1.110
LOW
31
1.370
1,«00
51
1.076
1.M3
1.121
1.101
33
l,38!t
1.311
53
1.6II0
1.W15
1.1«3
1.111
■Ait
1.403
1.8J4
S3
1.70.1
1..178
!.)«{
1.110
34
1.418
1.386
1 n4
1.730
l.SM
I.l.'i4
1.IS8
3.'i
1.431
1.848
1 .1.5
1.7.13
1.604
1.1««
1.1M7
sa
1.44.1
I.3RI
1 m
1.746
1.018
1,178
1.146
37
1.460
1.374
■ 57
1.7B3
1.630
1.180
i.ts.i
38
1.475
1.887
58
1.780
1.641
1-203
i.iae
30
1.400
1.400
58
1.783
1.0.13
80
1.315
1.177
40
1.50-1
1.411
60
1.810
1.007
Witb llie dpcreiue an<l
■nlalion BiilTcrB a cnrrespnnding
or the ceniiKritcte tliermomeler i
Fur solulJoD oTa Hpccllic gravity or l.i
nr tcmpernlurc, the spcc^lllc gravity nf llie
irreiRp I) r dec reuse, amountiDg fnreacb degree
eitlier direct I ou —
1.84
alHiut O.00055
1.315
0 0;t05
" 1.330
0.0004
1.010
" O.0O033
LIQUOR FOTASSn ARSENITIS.
I-KiUOR PoT.VSStI AIISENICOSI. I.TQUOIl KAI.II ARSENICOSI.
Salulioa of Petaifinm Aftenite. PiteUr't 8o!iilidn.
The officinal Holiition of potassium arsenite contains 1.656 per
cent, of primary potaaaium arscnit«, KnjA.sOy corresponding to
1 per cent, of arsenic trioxJde, AsjO^;* it has a slight alkaline
• Liquor Kalii urBenicosi of the PliBTmnPopoen Germanlca 1b an aqueoni •nln-
linnnf pomsninm metnaremiie. KAsO, ; anil prolmbly, nlsn. orpntMsiumorUia-
arseullea, corresponding in amuiiut to 1 por ceul, of arsenic irioiide, A.i,0,.
LIQUORES. 411
reaction, and gives, with nitrate of silver, a bright-yellow precipi-
tate, soluble in ammonia- water ; this solution, when gently warmed
for some time, by immersing the test-tube in hot water, sufTers a
reduction of the silver salt, and deposits the metal, as a brilliant
coating, upon the walls of the test-tube. Hydrogen sulphide pro-
duces no immediate precipitate in the solution of potassium arse-
nite, but, upon the addition of hydrochloric acid, there at once
appears a lemon-yellow precipitate, soluble in ammonia-water or
in a concentrated solution of ammonium carbonate.
Estimation :
A quantitative estimation of the amount of arsenic trioxide
(arsenious acid), corresponding to the amount of potassium ar-
senite contained in liquor potassii arsenitis, may be made by
diluting 10 grams of the solution with an equal volume of water,
acidulating with hydrochloric acid, and subsequently completely
f precipitating with hydrogen sulphide. The precipitate is col-
ectcd and washed upon a tared filter, and, after drying at 100°
C. (212° F.), is weighed. The weight of the arsenious sulphide,
divided by 1.242, gives the quantity of arsenious «acid contained
in 10 grams of the solution, which should be 0.1 gram.
The quantitative estimation may also be made volu metrically,
by the following method: 10 grams of the solution of potassium
arsenite are accurately weighed in a beaker, and the solution
diluted with about twice its volume of water. 2 grams of crys-
tallized sodium carbonate are then dissolved in the liquid, a little
mucilage of starch added, and subsequently a decinormal solution
of iodine (page 93) allowed to flow into the liquid, from a burette,
until a permanent blue coloration of the liquid is just, produced.
20.2 cubic centimeters of the iodine solution should be required
to produce this reaction, as corresponding to 0.1 gram of arsenic
trioxide, or, the amount of the latter may readily be calculated,
with the consideration that 1 cubic centimeter of decinormal iodine
solution corresponds to 0.00495 gram of arsenic trioxide, As^Oj.
The United States Pharmacopceia directs that if 24.7 grams of
the solution are boiled with 0.5 gram of sodium bicarbonate, the
liquid, when cold, diluted with 100 cubic centimeters of water,
and some mucilage of starch added, should require from 48.5 to
50 cubic centimeters of the volumetric solution of iodine, before
the blue color ceases to disappear on stirring (corresponding to 1
per cent, of arsenious acid of the required purity, or, at least, 0.97
per cent, of pure arsenious acid).
This hook is thepr<'^'
COOPER MEDICAL CO:.:.. .
SAN FRANCISCO. CAL.
civd iff not fn I*' r'"/i • '^ / " ' ^
n
412 MANUAL OF CHEMICAL ANALYSIS.
LIQUOR SOD2I.
LIQUOR SODII HYDRICI. LIQUOR NATRII CAUSTICL
Solution of Soda. Solution of Sodium Hydrate,
Gcr. Natronlauge ; Fr. Soude caustique liquide ; 8p. Solucion de sosa.
A transparent, colorless, limpid liquid, without odor, of an
extremely acrid and caustic taste and strongly alkaline reaction,
and having a soapy feel when rubbed between the fingers. It
has a destructive action on many vegetable and mineral substances,
is a i)owerfal solvent for many organic and mineral compounds,
and readily absorbs carbonic acid by exposure to the air; when
dropped into a concentrated solution of tartaric acid, no precipi-
tate IS produced (distinction from solution of potassium hydrate);
when a drop of the solution, contained on th« looped end of a
platinum-wire, is held in the non-luminous flame, it imparts to
the latter an intense yellow color. The specific gravity of the
solution is about 1.059 at 15^ C. (59^ F.), and it contains about 5
per cent, of sodium hydrate.*
Examination :
Sodium carbonate is indicated by effervescence, or by the forma-
tion of gas-bubbles, when the liquid is added to an excess of con-
centrated hydrochloric or nitric acid ; it may also be detected by
the formation of a white precipitate upon mixing a little of the
liquid with twice its volume of lime-water.
Sodium sul/Jwte tind chloride are indicated by white precipitates,
when the diluted liquid is slightly supersaturated with nitric acid,
and tested with barium nitrate for sulphate, and with argentic
nitrate for chloride.
Calcium salts may be detected by a white precipitate, when the
diluted liquid, previously neutralized with nitric acid, is tested
with solution of ammonium oxalate or sodium carbonate.
Potassium hydrate may be recognized by a white, granular pre-
cipitate, on dropping the liquid into a strong solution of tartaric
acid, allowing the latter to remain in excess.
Melallic i)n/jurities are indicated by a dark coloration or tur-
bidity when the lic^ior sodie is saturated with hydrogen sulphide,
either before or after supersaturation with hydrochloric acid.
Estimation :
The amount of pure sodium hydrate contained in liquor soda?
may readily be determined vol u metrically. About 20 grams of
the li([uid are accurately weighed in a beaker or small flask, a
few drops of litmus solution added, and subsequently a standard
soluti(m of oxalic or sulphuric acid (page 82) allowed to flow into
* Liquor Natrii canstici of the Pharraacopoea Germanica has a spec. grav. of
from l.l.jO to 1.1G3, and contains about 15 per cent, of sodium hydrate.
LIQUORES.
418
the liquid from a burette, until, with constant stirring, the blue
tint of the liquid is just changed to a clierry-red. From the
number of cubic centimeters of the acid solution thus required
for exact neutralization, the amount of pure sodium hydrate may
be calculated : one cubic centimeter of normal acid corresponding
to 0.040 gram of sodium hydrate, NaHO. By the employment of
20 grams of the officinal liquor soda?, not less than 25 cubic centi-
meters of the normal acid solution should be required for exact
neutralization, indicating a strength of at least 5 per cent, of
sodium hvdrate.
If the liquor sodie contains carbonate, the amount of carbon
dioxide contained in a weighed portion of the solution must be
determined, as described on pages 85-86. For 1 part of carbon
dioxide, CO^, 1.818 parts of sodiuni hydrate, NaHO, are deducted
from the amount volumetricallv indicated, and the balance then
calculated as pure sodium hydrate.
Table of the quantity hy weight of Sodium Oxide and Hydrate contained
in 100 parts by freight of solution {Liquor Soda) of different specific
gravities ( Gerlach).
Temperature 150 C. (59^ F.).
Per ct.
of NhjO
or
5aH0.
Specific
gfHviiy
for NaaO.
1
Specific
gravity
for NaHO.
1.012
Per ct. .
of NajO
or
NaHO.
21 .
Specific
graTiiy
for NasO.
1 1
\ Specific
giavity
for NaHO.,
1 '
Per ct.
uf Na^O
or
NaHO.
41
Specific !
gravity i
forNa-O. .
1
1.570
Specific
g'aTity
for NaHO.
1
I.OIT)
1.300
\ 1.236
1.447
2
1.020
1.023
22 '
1.H15
1 1.247
42
1 . 583
1.456
8
1.043
1.035
23 I
1.329
1.258 '
43
1.597
1.468
4
i.or.8
1.046
24 '
1.341
1.269
44
1.610
1.478
5
1.074
1.059
25
1.355
' 1.279
45
1.623
1.488
r>
1.080
1.070
26
1.369
' 1.290
46
1.637
1.499
7
1.104
, 1.081
27
1.381
1 1 300
47
1.650
1 . 508
8
1.119
1 . 092
28
1 . 395
1.310
48
1.663
1.519
9
1.182
1 103
29
1.410
1.321 ,
49
1.678
1.529
10
1.145
1.115
:;o
1.422
l.:i32 .
no
1 . 6»0
1.540
11
1.160
1.126
31
1.488
1.343
51
1 . 705
1 . 550
12
1.175
' 1.137
32
1.450
1.351
52
1.719
1.560
18
1.190
1.148
33
1.462
1.363
' 53
1.730
1.570
U
, 1.203
1.159
1 34
1.475
1.374
54
1 . 745
1 . 580
15
1 219
1.170
' 35
1.480
1.384
55
1.760
1.5»l
16
, 1.233
; 1.181
; 36
1.500
1.3i)5
i 56
1.770
1.601
17
1.245
1 1.191
i 37
1.515
1 . 405
1 57
1 . 785
1.611
18
1.2:.8
1.202
' 38
1.530
1.415 ,
; 58
•1.800
1.622
19
1.270
; 1.213
; 39
1 . 543
1.420
; 59
1.815
1.633
20
i 1.285
1.225
i 40
1
1 . 558
1.437
60
1 . 8;i0
1.643
With the decrease and increase of temperature, the specific gravity of the
solution suffers a corresponding increase or decrease, amounting, for each
degree of the centigrade thermometer in either direction —
For solution of a specific gravity of 1.830 to tliat of 1.355 to about 0.00045
1.341 »' 1.219 '' 0.0004
" ** ** ** 1.203 '* 1.015 '* 0.00C33
MANUAL OF CHEMICAL AKALYatS,
LIQUOR aODJE CHLOBATJB.
LlQUiHt SOD^ CIILORINAT.^. LIQUOR NATHII HYPOCBLOROSI.
Solution of Chlorinated Soila. Solution of Sodivm H]fpoehloril4.
A transparent liquid of a jmle greenieli-yellow color, lia?ine a
faint oiior, resembling that of cblorine, and a disagreeable allcs-
line taste and alkaline reaction. Its specific gravity is 1.044 at
15' C. (59^ P.), ami it contains about 2 per cent, of available
chlorine.
Solution of chlorinated soda becomes decomposed upon heat-
ing, with the formation of sodium chlorate and cliloride, and,
upon exposure to sunlight, liberates oxygen, with tlie i^imul taneoqs
formation of soilium ctilorate, chlorite, and chloride. It posscs,ica
oxidizing propertied, and is rendered much more energetic in it*
action by the addition of acids, in consequence of the developed
chlorine; it rapidly decolorizes solution of indigo and other
vegetable colors, and produces in the solutions of many metallic
Baits, such as lead, manganese, cobalt, and nickel, brown or black
precipitatea of the rcs])eelive peroxides or perhydrates; when
added to a solntion of ferrous sulphate, a copious, light-brown pre-
cipitate is produced, and with .solution of mercuric cliloride it
afftird:^ n brown precipitate of mercuric oxychloride, Hg,C!,0.
Examination :
Calcium ea/is will be indicated by a white precipitate nu the
addition of solution of sodium carbonate.
Sodium cnrbimnte, when present in any considerable excess, will
be indicated by the formation of a precipitate, when the solution
of clilnriiiatod soda is mixed with twice its volume of alcohol.
Estimation:
The value of liolulion of chlorinated soda depends upon the
amount of available chlorine which it contains, which may readily
be determined by the following method, 8.88 grams of tb«
solution arc mixed, in a beaker, with a solution of 2.6 grams of
potassium iodide in 200 cubic centimeters of water ; 18 grama of
nydr(x;iiloric acid ore subsequently added to the solution, together
with a few drops of mucilage of starch, and, after being well
iriixed, a standard solution of sodium hyposulphite (page 9-t) is
allowed lo flow into the liquid from a burette until, with constant
stirring, complete tlecoloration of the liquid is effected. If the
solution be of the proper strength, not less than 50 cubic cen-
timeters of the solution of sodium hyposulphite should be re-
quired to produce this reaction, indicating at least 2 per cent, of
available chlorine.
By the employment of other amounis of the solution of chlori
LITHIUM. 415
Dated soda, or, when the proportions above indicated are observed,
the exact amount of available chlorine contained in the solution
may also be calculated, by the consideration that 1 cubic cen-
timeter of standard sodium hyposulphite solution corresponds to
0.0035 gram of free chlorine.
LITHn BENZOAS.
LITHIUM BENZOICUM.
Bemoate of Lithium. Lithium Bemoate.
Gcr. Benzoesaures Lithium ; Fr. Benzoate de lithium ; Sp. Beuzoato de litina.
LiC,H,0,; 128.
A white powder, or small shining scales, permanent in the air,
of a faint benzoin-like odor, a cooling and sweetish taste, and a
faintly acid reaction. On being heated, the salt first fuses, then,
at a higher temperature, it chars, emitting inflammable vapors of
a benzoin-like odor, and finally leaves a black residue of an alka-
line reaction. A little of the salt, when heated on the looped
end of a platinum wire, in the non-luminous flame, imparts to the
latter an intense carmine-red color.
Lithium benzoate is soluble in 4 parts of water and 12 parts of
alcohol at 15° C. (59" F.), in 2.5 parts of boiling water and in 10
parts of boiling alcohol, but is insoluble in ether. Its aqueous
solution yields on the addition of a dilute'solution of ferric chloride
a flesh-colored precipitate of basic ferric benzoate, and with hydro-
chloric acid a precipitate of benzoic acid, which redissolves on
the subsequent addition of alcohol.
Examination :
Sulphates and chlorides may be detected in the diluted aqueous
solution of the salt, strongly acidulated with nitric acid, and fil-
tered, if necessary, by testing it in separate portions, with barium
nitrate for the former, and with argentic nitrate for the latter.
Potassium and Sodium Salts. — A small portion of the salt is
ignited, in a porcelain crucible, at a red heat, the ignited residue
dissolved in diluted hydrochloric acid, and the solution filtered
and evaporated to dryness. 1 part of this residue should be com-
pletely soluble in 3 parts of absolute alcohol, forming a solution
which, when ignited, burns with a crimson flame, and which is
not precipitated by the subsequent addition of an equal volume
of stronger ether; if the ignited residue be incompletely soluble
in alcohol, the presence of salts of the alkalies will be indicated.
Calcium, salts may be detected in the aqueous solution of the
above-described ignited residue, by the formation of a white pre-
cipitate when tested with solution of ammonium oxalate.
416 MANUAL OF CHBMIOAL ANALYSIS.
Metallic impurities may be detected in the aqueous solution of
the salt, acidulated with hydrochloric acid, and filtered, if neces-
sary, by a dark coloration or a turbidity when saturated with
hydrogen sulphide, or, after neutralization with ammonia-w^ater,
by the addition of ammonium sulphide.
LITHII BROMIDUM.
LITHIUM BROMATUM.
Bromide of Lithium. Lithium Bromide,
Ger. Broralit Ilium ; Fr. Bromure de lithium ; Sp. Bromnro de litio.
LiBr; 86.8.
A white, granular salt, very deliquescent on exposure to the
air, neutral in its action upon litmus, and possessing a sharp and
slightly bitter taste. On exposure to a low, red neat the salt
fuses, and, at a higher temperature, it is slowly volatilized. A
fragment of the salt, contained on the looped end of a platinum-
wire, when brought into the non-luminous flame, imparts to the
latter a carmine red color.
Lithium bromide is very freely soluble in both water and alco-
hol ; its aqueous solution yields on the addition of a solution of
argentic nitrate a yellowish-white precipitate, which is soluble in
a large excess of ammonia-water. If a little carbon bisulphide
be poured upon a solution of the salt, a few drops of chlorine-
water subsequently added, drop by drop, and the whole well agi-
tated, the carbon bisulphide will acquire a yellowish or brownisb-
red color, but should show no violet tint.
Examination :
Alkaline hromides, iodides, and chlorides may be tested for by
dissolving 0.1 gram of the dry lithium bromide in 10 cubic cen-
timeters of water, adding thereto a solution of 0.2 gram of argentic
nitrate in about 10 cubic centimeters of water, agitating the mix-
ture, and filtering. The filtrate should not become turbid on the
subsequent addition of solution of argentic nitrate, and the above-
obtained precipitate should be completely soluble in a large excess
of ammonia water; a turbiditv in the first instance would indicate
chloride, and incomplete solubility in the second instance, the
presence of i(xlide. As a special test for potassium bromide, 0.1
gram of the dry lithium bromide and 0.19 gram of argentic nitrate
are dissolved, se])arately, in small portions of water, the solutions
mixed, agitated, and filtered; the filtrate should remain clear
upon the addition of a few drops of hydrochloric acid; if a pre-
cipitate is thereby produced, tlie presence of potassium bromide
or other potassium or sodium compounds will be indicated.
LITHIUM. 417
Potassium and Sodium Salts. — These impurities, in addition to
the above tests, will be indicated by dissolving one part of the
lithium bromide in three parts of absolute alcohol ; a clear solu-
tion should be formed, which should not be rendered turbid nor
yield any precipitate on the subsequent addition of an equal
volume of stronger ether, otherwise an admixture with salts of
other alkalies will be indicated.
Calcium salts may be detected in the aqueous solution of lithium
bromide by a white precipitate when tested Avith solution of am-
monium oxalate.
Metallic impurities may be recognized in the aqueous solution
of the salt, acidulated with hydrochloric acid, by a dark colora-
tion or a turbidity when saturated with hydrogen sulphide, or, after
neutralization with ammonia-water, by the addition of ammo-
nium sulphide.
LITHn CARBONAS.
LITHIUM CARBONICUM.
Carbonate of Lithium, Lithium Carbonate,
Ger. KohlensAures Litliiiini ; Fr. Carbonate delilhiiim ; Sp. Carbonato de litina.
Li^CO,; 74.
A white, amorphous, or indistinctly crystalline powder, perma-
nent in the air, odorless, of an alkaline taste and reaction, and
having a specific gravity of 2.11. When a small portion of the
salt is heated on the looped end of a platinum- wire, in the non-
luminous flame, it fuses to a clear, colorless bead, and imparts to
the flame a bright carmine-red color.
Lithium carbonate is soluble in 130 parts of water at 15° C.
(59® F.), and in about the same quantity of boiling water; it is
more freely soluble in solutions of ammonium salts, and is readily
dissolved by dilute acids, with copious evolution of carbon di-
oxide, but is insoluble in alcohol. If the solution of the salt in
diluted hydrochloric acid be evaporated to dryness, the residue
should be completely soluble in three parts of absolute alcohol,
affording a solution which, when ignited, burns with a crimson
flame, and which is not precipitated by the addition of an equal
volume of stronger ether (distinction from potassium and sodium
chlorides); if the acid solution of the salt be neutralized by
sodium hydrate, and a few drops of solution of sodium phosphate
are subsequently added, and gently heated, a white, crystalline
precipitate of lithium phosj^liate, readily soluble in hydrochloric
acid, will appear.
Examination :
Potassium and Sodi^im Carlonntes, — The presence of these salts
27
418 MANUAL OF CUBMICAL ANALYSIS.
may readily be ascertained by a greater solubility in water than
that above indicated, as also by tlie above-described method,
depending upon the solubility of lithium chloride in a mixture
of alcohol and ether.
Their presence mav also be determined bv the amount of acid
required to exactly neutralize a definite amount of the salt: 0.74
part of lithium carbonate, when mixed with a warm .solution of
1.26 parts of oxalic acid in 13 parts of water, should attbrd a clear
and neutral solution ; or, 1 gram of lithium carbonate, if perfectly
pure, should be exactly neutralized by 27.02 cubic centimeters of
normal sulphuric acid. Potassium salts may be sj^ecially tested
for, if desired, by dissolving a portion of the salt, in a test-tube,
in an excess of solution of tartaric acid, and drawing a glass rod
over the interior surface of the tube ; the gradual formation of a
white, crystalline precipitate will reveal the presence of potas-
sium salts. Sodium salts may also be further recognized by their
})roperty of imparting an intense yellow color to the non-lumi-
nous flame, when a portion of the carbonate, moistened with
hydrochloric acid, is heated on the looped end of a platinum-wire.
Ammonivvi salts mav be rccojrnized bv the odor of ammonia,
when a portion of the carbonate is heated, in a test-tube, with a
concentrated .^^olution of potassium or sodium hydrate.
Calcium, and maynesium salts, if present in the form of carbon-
ates, will remain undissolved when the lithium carbonate is agi-
tated with loO times its weight of water; they will also Ihj
indicated in the neutral solution of the salt (1:150) in diluted
hydrochloric acid by a white ])recipitate on the addition of an
excess of sodium carbonate. The presence of calcium salts may
be further detected in the aqueous s()luti(m of tlie lithium car-
bonate, previously neutralized witli hydrochjoric acid, by a white
tnrbiditv with ammonium oxalate; after filtration, if necessary,
and the addition of ammonium chloride, ammonia-water, and
solution of sodium phosphate, an ensuing white crystalline pre-
cipitate will reveal the j)rcsence of magnesium.
Snlfihatt^s and chlorides may be detected in the solution of the
carbonate in diluted nitric acid, when tested, in separate portions,
with barium and arofentic nitrates respectively.
Metallic iiii purities may be recognized in the solution of the salt
in diluted hydrochloric acid by a dark coU)ration or a turbidity
upon saturation with hydrogen sulphide, or, after neutralization
with ammonia- water, by the subsequent addition of ammonium
sulphide.
LITHIUM. 419
LITHII CITRAS.
LITHIUM CITRICUM.
Citrate of Lithium. Lithium Citrate,
Ger. Citronensaures Lithium ; Fr. Citrate dc lithium ; Sp. Citrato de Htina.
Li,C,H,0,; 210.
A white, amorphous, deliquescent powder, possessing a slightly
cooling and faintly alkaline taste, and neutral in its action upon
litmus. When exposed to a red heat, the salt chars, evolves
inflammable vapors, and leaves a black residue of an alkaline
reaction, which, when dissolved in a little alcohol, with one or
two drops of hydrochloric acid, and ignited, imparts a crimson
color to the flame.
Lithium citrate is soluble in 5.5 parts of water at 15° C. (59°
F.), and in 2.5 parts of boiling water, but is almost insoluble in
alcohol and ether. When the aqueous solution of the salt is
completely precipitated with calcium chloride, the filtrate, when
heated, will become turbid, and when filtered after cooling, and
the filtrate reheated to boiling, it becomes turbid again (evidence
of the presence of a citrate).
Examination :
The purity of lithium citrate may be approximately deter-
mined by adding to 1 gram of the salt, previousl}*^ dried at 120°
C. (248° F.), and contained in a porcelain crucible, about 3 grams
of concentrated sulphuric acid, and gently heating. After com-
plete carbonization, the residue is strongly ignited at a red heat,
and, after cooling, is weighed. The weight of the lithium sulphate
thus obtained should not exceed 0.79 gram, and, when multiplied
by 1.273, will indicate the corresponding amount of pure lithium
citrate.
Potassium salts are detected in the concentrated solution of the
citrate, by a white, crystalline precipitate, upon the addition of a
few drops of concentrated solution of sodium bitartrate.
Sodium salts are detected in the solution by a white precipitate
when tested with potassium antimoniate, or by a persistent yellow
color imparted to the non-luminous flame, when heated on the
looped end of a platinum-wire.
The presence of potassium and sodium salts may also be ascer-
tained by dissolving, in oue or two drops of diluted hydrochloric
acid, the residue of lithium carbonate obtained by incineration of
the citrate; this solution is evaporated to dryness, and is subse-
quently dissolved in a few drops of a mixture of equal parts of
alcohol and ether ; a complete solution should result, as an insolu-
ble residue would indicate potassium or sodium chlorides.
Metallic impurities may be detected in the solution, acidulated
420 MANnAL OF CHEMICAL ANALTSIS.
with hydrochloric acid, by a dark coloration or a turbidity upon
saturation wiih hydrogen sulphide, or, after neutraliaation with am-
monia-water, by the fiubsequeut addition of ammouium sulphide.
LITHII SALICTLAS.
LITHIUM SAI.ICYLICUM.
Snlii-J/liiU of Lilhivm. Lithium Salitylale.
Gcr. SalicylsfiiirPB Lllliiuro [ Fr. Salicylate dc lUliium ; Sp. SalicIUto de Htlno.
2LiC,n,0j.H,0; 306.
A white powder, deliquescent on exposure to the air, and con-
taining, for two molecules of the salt, one molecule (5.88 per cent.)
of water. When strongly heated, the salt chars, emits inflamma-
ble vapors, and leaves finally a blackened residue of an alkaline
reaction. A small portion of the salt, when heated on the looped
end of a platinum-wire in the non-luminous flame, imparts to the
latter a bright carmine- red color.
Lithium salicylate is very freely soluble In both water and alco-
hol. Its aqueous solution possesses a nweetish taste, and a Faintly
acid reaction, and yields, upon aupersntu ration with hydrochloric
acid, a bulky white precipitate of salicylic acid, whicli ia soluble
in boiling water, and from which it recrystallizes ou cooling; the
precipitate is also readily soluble in alcohol and ether, and the
solutions assume, on the addition of a drop of solution of ferric
chloride, an intense violet color.
Examlnatioii ;
Or-jnnir impurities may, in most cases, be detected by agitating
1 part of the salt with about 15 pans of concentrated sulphuric
acid, when no color should Vie imparted to the acid within 15
minutes; an ensuing dark coloration would indicate the presence
of foreign organic substances.
Carbonate will be indicated by effervescence, when a amall por-
tion of the salt is added to diluted hydrochloric or acetic acid.
Potaasium and sodnim nalts may be recognized by igniting a
portion of the lithium salicvlate at a red heat, dissolving the resi-
due in diluted hydrochloric acid, and evaporating the clear, fil-
tered solution to dryness. The residue of lithium chloride thus
obtained should be completely soluble in 3 parts of stronger alco-
hol, affording a solution, which, when ignited, burns with a crira-
pon flame, and the transparency of which is not disturbed by the
subsequent addition of an equal volume of stronger ether: if an
insoluble residue remains, the presence of potassium or sodium
sails or other impurities will be indicaled.
Metallic impurities may be detected in the aqueous solution of
^
MAGNESIUM. 421
the salt, acidulated with hydrochloric acid, by a dark coloration
or a turbidity upon saturation with hydrogen sulphide, or, after
neutralization with ammonia-water, by the subsequent addition
of ammonium sulphide.
MAaNBSIA.
MAGNESIA USTA. MAGNESII OXIDUM. MAGNESIUM
OXYDATUM.
Magnesia. Calcined Magnesia. Magnesium Oxide,
Ger. Gebrannte Magnesia ; Fr. Magn^sie calcin^e ; Sp. Magnesia calcinada.
MgO; 40.
A white, inodorous, bulky, more or less lis^ht powder,* of an
earthy, but not saline taste, and a slightly alkaline reaction upon
moistened red litmus-paper; when exposed to a moderate heat,
it suffers no change, but at very high temperatures it is rendered
more dense, loses its property of combining with water, and is
much more slowly soluble in acids.
Magnesia is almost insoluble in water, requiring 55,368 parts
of the latter for solution, but is much more soluble in solutions
of various salts, particularly the ammonium salts; it is insoluble
in alcohol. If one part of magnesia be stirred, in a beaker, with
15 parts of water, and the mixture allowed to stand for about
half an hour, it readily unites with the water with the formation
of a gelatinous hydrate, which is of suflScient firmness to prevent
it from falling out when the glass is inverted, and gradually
absorbs carbonic acid by exposure to the air. When magnesia is
dissolved in diluted sulphuric acid, it affords a solution which,
after the addition of ammonium chloride and supersaturation with
ammonia- water, yields a white, crystalline precipitate on the addi-
tion of solution of sodium phosphate.
lamination :
When triturated with hot water, and the mixture poured into
an excess of dilute sulphuric acid, magnesia must dissolve with-
out effervescence (evidence of the absence of carbonate)^ and must
form a clear solution (evidence of the absence of calcium^ barium^
and strontium oxides) ; this solution may be divided into two
portions, one of which is saturated with hydrogen sulphide, and
after filtration, if necessary, and neutralization with ammonia-
water, tested with ammonium sulphide; a dark coloration or a
turbidity in either instance will indicate the presence of metallic
* In the U. S. Pharmacopoeia magnesia is ofl9cinal in two forms, as Magne-
sia, or light magnesia, and Magnesia Ptmderosa, or heavy magnesia, which
differ in their densities, but correspond in all their other properties and
reactions.
422 MANUAL OF CHEMICAL ANALYSIS.
jmpurilies: the remaining portion of the solution, after the addi-
tion of a little ammonium chloride and ammonia -water, is tested
with ammonium oxalate, when a white precipitate will reveal the
|iresencc of calcium. Another portion of the magnesia may be
dissolved in dilute nitriu acid, and the solution tented, in separate
jtortions with argentic nitrate for chlorides, and with barium nitrate
or chloride for sulpbntes.
Magnesia is liable to contain the impurities of the magnesiam
carbonate from which it lias been obtained, and may bo further
examined for them, if tliey have not been ascertained by tlio
precedinj; tests I'or idenlilv and purity, by the methods described
on page 423.
MAONESII CARBONAB.
MAGNESIUM CARUtJNlCrM, MAGNESIA ALBA.
Oarbonatn nf Magnesium. Magneniun Carbonat*.
(MgCO,)..Mg(On),+ fiII,0;» 522.
"White, bulky, pulverulent maa.ses, commonly in square cakes,
or a light, white powder, smooth to the touch, and nearly insolu-
ble in water, but soluble with efterveaceuce in dilute acids, yield-
ing limpid, colorless solutions ; these, after the addition of a little
Bolntion of ammonium chloride, are not precipitated upon slight
RUpersaturation with ammonia-water, but, upon the subsequent
additiou of sodium phosphate, aftbrd a white crystalline precipi-
tate of ammonio-magnesium phosphate. It is also soluble m
solutions of the alkaline carbonates, potassium chloride, sulphate,
and nitrate, borax, and particularly in solutions of ammonium
salts, with the formation of soluble double salts.
Magnesium carbonate is decomposed at a red heat, and also by
all acids, and hy the fixed alkaline hydrates. 1(H> parts of it,
when ignited at a red heat until the weight remains constnot,
nhould leave a residue of magnesium oxide amounting to at least
40 parts.
Examination :
A small portion (about 1 gram) of the powdered magnesium
carbonate is mixed and agitated with about 20 times its weight of
warm water, and filtered ; the filtrate is tested with turmeric paper,
and, if this l>ecoraes brown, alkaline carlmnatf a an indw&ted ;.wnan
• Tlio composilion of mngneBlnm cnrboiial^ differs ■omewlml according In
llie melliiHl nr prPiMrnDni. AttLnuicli lliu rommc^rcml hfIIcId iiiually ciirre-
apomls to IliF iibiive Tormula, llie ninnuDl of irnler vnrics tR'tweeii 4 anii S mnle-
MAGNESIUM. 423
a few drops of the filtrate are evaporated upon platinum-foil, only
a very slight residue should remain. The magnesium carbonate
left on the filter is rinsed into a flask, by means of a wash- bottle,
the mixture warmed, and sulphuric acid added, drop by drop,
until solution is effected ; a remaining slight turbidity would
indicate traces of silicic acid. The solution is filtered, if neces-
sary, and saturated with hydrogen sulphide, when a dark colora-
tion or precipitate v/ill indicate lead or copper ; after filtration, if
necessary, the liquid is rendered alkaline by the addition of am-
monia-water; an ensuing black precipitate would indicate salts of
iron; a light reddish one, salts of manijanese ; a white one, salts
o{ aluminium or zinc (the incidental presence of phosphates would
also give a white precipitate). In order to distinguish the latter,
the precipitate is washed, subsequently dissolved in a little dilute
hydrochloric acid, and. after gently heating to expel the hydrogen
sulphide, the solution is supersaturated with ammonia-water; the
aluminium is thereby precipitated, while zinc remains in solution,
and may be recognized by re-precipitation with hydrogen sulphide
or ammonium sulphide.
The ammoniacal filtrate is then tested with a few drops of
ammoniu?n oxalate; a white precipitate, insoluble upon the aildi-
tion of ammoniufn chloride, would indicate salts of calcium. The
latter may be further specially tested for, if required, by igniiinsr
a portion of the magnesium carbonate, extracting with water and
filtering, and, after the addition of a little ammonium chloride
and ammonia-water, testing the filtrate with ammonium oxalate.
Chlorides and sulphates may be detected, in the diluted solution
of the miijjnesium carbonate in diluted nitric acid, by testing the
same in separate portions, with barium nitrate for sulphates, and
with argentic nitrate for chloride.
MAGNESII SULPHAS.
MAGNESIUM SULFURICUM.
Epsom Salt, Sulphate of MagneHum. Majnenium Sulphate.
Ger. Schwefelsaures Magnesium, Bittersalz ; Fr. Sulfate de magn^sie ;
Sp. Sulfato de magnesia.
MgS0,-|-7H,0; 246.
Colorless, transparent, four-sided rhombic prisms (Fig. 136), but
usually met with in commerce as small, acicular needles ; they con-
tain seven molecules (51.22 per cent.) of water of crystallization,
six of which are eliminated at 120° C. (248^ F.), while the last
molecule is not expelled at temperatures below 220^ C. (428^ F.);
the crystals do not effloresce at common temperatures and in ordi-
424
MANUAL OF CUBMICAL ANALYSIS.
FlO. 136.
nary atmosplierio liumitlily, but itiey lio so slowly in wiirta, dry
air. Wlien heated, tliey lose their water of erystallizaiioa with-
out previously undergoing aqueous fusion, and at a red heat
undergo igneous fusion, with partial decom-
poaition.
Magnesium sulphate is soluble in 0.8 part of
water at 15" C, (59° F.), and in 0.15 part of boil-
ing water, but is insoluble in alcohol ; its aque-
ous solution has a nauseous, bitter taste, ana is
iieutrai in its action upon litmus; it is deoom-
jio.sed, and gives white precipitates, with the
lixed alkaline hydrates and carbonates, and also
with the earthy hydrates and their soluble sails;
iunmonia-waterand ammonium carbonate, how-
ever, do not at once cause a precipitate iu dilute
solutions of magnesium sulphate, or, if so, but
a very slight one, since ammonium salts when present, or when
formed by the neutralization of acidulous solutions, act as a solv-
ent for magnesium hydrate or carbouate, and thereby retard or
prevent their precipitation; but, on the subsequent addition of
phosphoric acid or solutions of tri-basic phosphates, a complete
precipitation takes place, which precipitate, however, is soluble in
dilute acids.
The crystals of magnesium sulphate are isomorphous with
those of zinc sulphate, aud cannot be distinguished from tbem by
the eye; it is easy, however, to discriminate between them, not
only by the difference in taste, but also by the action of a few
drops of ammonium sulphide or solution of potassium ferrocyanide
on their aqueous solutions; that of magnesium sulphate remains
unaffectfd by these reagents, whereas solution of zinc sulphate
yields, in eitner instance, a white precipitate,
EKamlnatlon :
MetalUr. imfmrilt'es may be detected in the solution of the salt,
acidulated with hydrochloric acid, by the occurrence of a turbidity
or precipitate upon saturation with hydrogen sulphide (an ensuing
white turbidity may be due simply to sulphur, a lemon-yellow
one will indicate arsenic), and, alYer filtration, if necessary, and
neutralization with ammonia-water, by the subsequent addition
of ammonium sulphide; a white precipitate with the latter re-
agent would ind catc zinc; when a dark precipitate is formed,
both with the hydrogen sulphide and ammonium sulphide, cop-
per and iron arc indicated, and may be confirmed in the slightly
acidulated solution of the salt, the former by a reddish-brown pre-
cipitate, the latter by a bine one, with potassium ferrocyanide.
Alkaline iulphatfs may be detected by triturating 2 parts of the
magnesium sulphate with an equal weight of dry calcium hydrate
(from which any free alkali must have been previously removed
by washing with water, and again drying), and adding this mix-
k
MAGNESIUM^ 423
ture to a mixture of 10 parts of alcohol and 10 parts of water.
The mixture is then allowed to stand for about two hours, with
frequent agitation, when 40 parts of absolute alcohol are added,
and, after active agitation, the mixture poured upon a filter which
has been previously moistened with alcohol. If an alkaline sul-
phate be present in the magnesium sulphate, it will be contained
m the alcoholic filtrate in the form of hydrate, and may then
readily be detected by its action upon turmeric paper ; • if litmus
paper be employed, the alcoholic liquid should be mixed with a
little water, and the alcohol dissipated by the aid of heat before
the application of the test.
Amrnonium salts may be detected by the odor of ammonia, when
a little of the salt is heated, in a test-tube, with a strong solution
of potassium hydrate, or by the d'^velopment of white fumes
when a glass rod, moistened with acetic acid, is held over the
orifice of the tube.
Aluminium and Calcium Salts, — The former may be detected in
the solution of magnesium sulphate, to which a sufficient amount
of ammonium chloride has been added, by the formation of a
colorless, flocculent precipitate on the addition of ammonia- water;
and the latter by a white precipitate on the addition of ammonium
oxalate.
Chlorides may be detected in the diluted solution of the salt,
acidulated with nitric acid, by a white turbidity on the addition
of solution of argentic nitrate.
Estimation :
One hundred parts of magnesium sulphate, dissolved in boiling
water, and completely precipitated by a boiling solution of sodium
carbonate, yield a precipitate which, when washed, dried, and
ignited at a red heat, weighs 16.26 parts.
The quantitative estimation of magnesium in magnesium sul-
phate is, however, usually eftected by its precipitation as ammonio-
magnesium phosphate, and the conversion of the latter, by ignition,
into magnesium pyrophosphate ; from the weight of the latter, the
amount of magnesium oxide, or the corresponding amount of
crystallized magnesium sulphate may readily be calculated. To
the aqueous solution of a wei;/hed amount of the salt, ammonium
chloride and ammonia- water are added, and subsequently solution
of sodium phosphate until no further precipitate is produced ;
the mixture is allowed to stand for ten or twelve hours, when the
precipitate is collected upon a filter, washed with a mixture of
about one part of aminonia-water and three parts of water, and,
when dry, completely incinerated in a porcelain crucible. Of the
residue of magnesium ])yrophosphate, Mg^PjO,, thus obtained,
100 parts correspond to 36.03 parts of magnesium oxide, MgO, or
221.62 parts of crystallized magnesium sulphate, MgSO^-f- 711^0.
426 MANUAL OF.CHBMICAL A9ALTSTS.
MAGNESIUM SULFCROSUM.
Sulphite of Jiagneii>iin, M'lgiieniatn SulphiU.
Gcr. Schweflijfsaares Mi?n*?j»inm ; Fr. Sulfite de ma^esie;
Sp. Sulfite de magnesia.
MgSOj + tJnjO: 212.
A white, crystalline powder, containing t) molecules (50.9-4 per
cent.) of water of crystallization: it is oil.>rless, but possesses a
sliL'htlv bitter, somewhat sulphurous, taste, and a neutral or
slightly alkaline rea<.'tion ; on exf>osure to the air, it gradually
absorbs oxycren, and becomes converter! into magnesium sulphate.
When heated to 2«W° C. (:5i:>2® F.\ the salt loses'its water of'crvs-
tallization, and becomes decomposed, being concerted into mag-
nesium oxide and anhydrous maizncsium sulphate.
M:i«-rnesium sulphite is soluble in 20 parts of water at 15® C.
(."iO -' F.), and in 1*J parts of boiling water ; it is insoluble in alcohol.
The aqueous solution, when mixed with solution of ammonium
chloride and ammonia-water, yields, upon the subsequent addition
of S'»lution of so<Jium j>hosphate. a white crystalline precipitate,
which is insoluble in water or dilute ammonia-water, but readily
soluble in acids.
M:tixne^iuni sulphite is also completely soluble in 4 times its
weiL'^ht of dilute hydrocliloric acid, with th*^ development of the
od«»r of burning sulphur, bat without producing any turbidity
(<listin<!ti«>n from magnesium hyposulphite). A 1 {>er cent, aque-
ou-s solution of the salt, strt^nuiv acitlulated with hvdrochloric
acid, should not attord more than a slight clouiliness on the ad-
dition of solution of b;irium chloride (absence of and distinction
from magnesium "sulphate).
MANGANI OXIDUM NIORUM.
M.VN^AXUM nYPEUOXVD.VTL'M. MWGANE^ICM OXVD.VTU.M
NATIVUM.
Black Oxi'ie of yfanjirnfne. Pyrolu*itf. yfang'Uif^e Dioxide.
Ger. Mangansuperoxyd, Brannstoin ; Fr. Oxyde de manganese ;
Sp. Peroxido de manganeso.
MnO,; 8H.
Heavy, compact masses, of a dull-black or brownish- black,
earthy appearance, or masses of acicular or rhombic crystals of a
black, metallic lustre, and, if pure pyrolusite, of a spec. grav. of
4.0. In commerce, it occurs usually ground, as a coarse, dull,
MANOANUM. 427
black powder, consisting of manganese dioxide, sesqui-oxide, and
monoxide, and is contaminated with the gangue (quartz, felspar,
barytes, limestone, etc.), which frequently amounts to 40 or 50 per
cent.
Manganese dioxide is infusible, permanent in the air, and in-
soluble in water or alcohol. When exposed to a strong red heat,
it loses one- third of its oxygen, and is converted into reddish-
brown mangano-manganic oxide, MnjO^: SMnO^asa Mn30^ + 0,.
It is not attacked by cold concentrated sulphuric acid, but,
upon heating with the latter, it is converted into manganous sul-
phate, with the evolution of oxygen: MnOj + II,SO^ =» MnSO^-^
11,0 + 0.
If, however, oxalic acid, or other readily oxidizable organic
substances are present, manganese dioxide is also dissolved by
dilute sulphuric acid, with the evolution of carbon dioxide:
MnO, + n,SO, + C,H,0, « MnSO, + 2C0, + 211,0.
When heated with hydrochloric acid, it is converted into man-^
ganous chloride, with the development of chlorine :
MnO, + 4UC1 = MnCl, 4- 2n,0 + 01,.
The resulting brownish solution, when filtered and neutralized
with ammonia-water, yields, with hydrogen sulphide or ammo-
nium sulphide, a flesh-colored precipitate of manganous sulphide ;
the color of this precipitate is, however, frequently rendered
darker, or even brownish-black, by the presence of oxides of
iron and other metals.
When a small portion of manganese dioxide is mixed with
about an equal weight of potassium hydrate and a little potas-
sium nitrate or chlorate, and the mixture heated to redness upon
platinum-foil, it yields a dark green mass, which dissolves in
water with a green color, chant^ing to purple when the solution
is boiled or on the addition of dilute sulphuric acid.
Examination :
As manganese dioxide is frequently employed in connection
with potassium chlorate for the generation of oxygen gas, its per-
fect freedom from organic contaminations should be conclusively
established, as the latter may give rise to violent and dangerous
explosions. The presence of organic impurities in general may
be determined by strongly heating a little of the powdered manga-
nese dioxide in a glass tube, when no combustion should take
place, nor should carbonic acid gas be evolved.
Black antimonions sulphide, which, by accident or through care-
lessness, may become mixed with or substituted for manganese
dioxide, may be readily detected by the development of the odor
of hydrogen sulphide in contact with dilute hydrochloric acid,
and, after boiling with the latter, and filtering, by the production
of an orange-colored precipitate upon saturation with hydrogen
sulphide.
428
, OP CUBUICAL AKALTSIS.
Since, however, the value of commercial black oxide of manga-
neae or pyrolnsite, for most of it.'< applications in the arts and
trades, depends less upon the nature of its impiirities than upon
the percentage of real manganese dioxide, an examination of the
mineral is invariably required before its ap-
Fio. 187. plication, and is mainly d reeled to the deter-
mination of the amount of dioxide.
Among the several methods of conductin}{
the assay, the two following are simple xnd
accurate, the one being an approximate, the
other a quantitative one :
I. Five grams of the finely powdered black
oxide of manganese are a<)ded, in a small
flask (Fig. 137), to a solution of 21 grams
of crystallized or granular ferrous sulphate
in 15 grams of water and 45 grams of hy-
drochloric acid, and, when mixed by gentle
agitation, the whole is heated for a few
minutes to boiling; after being allowed to
cool, the liquid is filtered, and the filtrate subsequently tested with
potassium ferricyaiiide; if it gives uo blue precipitate, the lest
bears evidence that the pyrolusite contains at least 66 per oent.
of real manganese dioxide; if a blue precipitate is produced, the
peroxide is wanting in llmt strength in proportion to the amount
of llie precipitate.
II. Three grams of the black oxide of manganese, in fine pow-
der, and previously dried at about 120° C. (248° F.), are care-
fully introduced into the flask K'
(Fig. 13IS) of the little apparatus
described on page 86, into which
previously has been poured suf-
ficient of a mixture of 1 part of
concentrated sulphuric acid and
2 parts of water to 611 the flaak
to about one-third of its capacitT.
Tlie apparatus is then brougnt
upon the balance, and, together
wiih from 8 to 9 grams of pure
< rysliillized oxalic acid, is occu-
I iiL-ly WL'ighed. The oxalic »cid
i< ihcn added to the mixture,
IjL'iiig careful to avoid any loss,
the cork carrying ihe lubes is adjusted, and the ensuing reaction
effected by gentle agitation; the flask K is charged with a little
concentrated sulphuric acid, through which the evolved carbomo
acid gas has to pass, and which absorbs and retains the moiatnre;
gentle heat is applied to the flask K', as long as a brisk evolution
of gas takes place ; the process is completed when this action and
MANOANUM. 429
the passage of gas-bubbles through the sulphuric acid both cease,
and the black color of the mixture has changed to a more or less
brown one; the residual gas is then driven off, by momentary
ebullition, and the apparatus again weighed. Every two mole-
cules of carbonic acid evolved correspond to one molecule of
manganese dioxide decomposed ; the molecular weight of the
latter (87) being so nearly equal to twice that of carbonic acid
(44), that the loss of weight suffered by the apparatus may be
taken to represent the quantity of real manganese dioxide in the
3 grams of the sample employed ; and it has only to be divided
by 3 and multipliea by 100 in order to express the percentage.
MANOANI SULPHAS.
MANGANUM SULFURICUM.
Sulphate of Manganese, Manganowt Sulphate,
Gcr. Schwefelsftures Mangnn ; Fr. Sulfate dc manganese ; •
8p. Sulfate dc manganeso.
MnSt\ + 4H,0; 222.
Colorless or pale rose-colored j)rismatic crystals, occurring in
three different forms, with different quantities of water of crys-
tallization: (1) Monoclinic prisms (isomorphous with ferrous sul-
phate), containing seven molecules of water of crystallization, and
obtained when crystallized at a temperature below 6° 0.(42.8° F.);
(2) Triclinic prisms (isomorphous with cupric sulphate), contain-
ing five molecules of water of crystallization, obtained when
crystallized at a temperature between 7° and 20° C. (4:4.6° and
68° F.); and (3) Quadratic crystals or large monoclinic prisms,
containing four molecules of water of crystallization, and obtained
when crystallized between 20° and 30° C. (68° and 86° F.).
The latter salt is the one commonly met with. The crystals
are permanent in the air, though slightly efflorescent in air that
is dry and warm ; they are soluble in 0.8 part of water at 15° C.
(59° F.), and in 1 part of boiling water, but insoluble in alcohol ;
the aqueous solution is neutral and colorless, or has, when con-
centrated, a faint rose-color; its taste is astringent, and it affords,
with the alkaline hydrates and carbonates, white precipitates, of
which those with the hydrates gradually become yellow, and
finally dark-brown, by oxidation; ammon um sulphide produces
a flesn-colored precipitate soluble in dilute mineral acids, and also
in acetic acid (distinction from zinc); tannic acid or tincture of
nutgall does not act apon the solution ; potassium ferrocyanide pro-
duces a reddish-white prec'pitate, ana potassium ferricyaniae a
430 MANUAL OP CHEMICAL ANALYSIS.
brown one ; with barium nitrate or chloride it yields a white pre-
cipitate, insoluble in hydrochloric acid.
When a fragment of a crystal of manganous sulphate is heated
with one or two drops of solution of potassium hydrate and a
little potassium chlorate or nitrate, upon platinum-foil, it yields a
bluish-green fuse.
Examinatioii :
Ferrous and cupric sulphates are detected, in the diluted solu-
tion, acidulated with hydrochloric acid, the former by a blue
precipitate with potassium ferrocyanide, the latter by a reddish-
brown one with the same reagent, or a black one with hydrogen
sulphide.
Mayntshim and alJcaUne sulphates may be detected by com-
pletely precipitating the dilute solution of the salt with ammon'um
sulphide, and by testing part of the filtrate with sodium phos-
phate; a white, crystalline precipitate will indicate magnesium
sulphate: if no reaction has taken place, another portion of the
filtrate is evaporated in a porcelain capvsule, and the residue heated
to redness uj)on platinum-foil ; a fixed remainder would indicate
potassium or sodium salts.
MORPHINA.
MORPHIUM. MORPHINUM.
MorpJiine, Morphia.
Ger. Morphin ; Fr. Morphine ; Sp. Moi-fina
C,,n,,N03.H,0 ; 303.
Small, brilliant, prismatic crystals, transparent and colorless, or
a white, crvstalline powder, containing one molecule (5.94 per cent.)
of water of crystallization. When heated to 120^ C. (248^ F.),
the crystals lose their water of crystallization and become opaque,
and, when cautiously further heated, they melt without decom-
position, assuming a crystalline form on cooling; at temperatures
above 200" C. (31)2° F.), they become decomposed and blackened,
and, when strongly heated on platinum-foil, they burn away, leav-
ing a carbonaceous residue, which is wholly dissipated at a red
heat.
Morphine is but sparingly soluble in cold w^ater, requiring at
lo"^ C. (r)l)° F.) 1000 parts of the latter for solution, but is soluble
in 500 parts of boiling water, in 100 parts of alcohol at 15® C.
(59^ F.), and in 30 parts of boiling alcohol; it is very sparingly
soluble in ether and chloroform, and insoluble in benzol, petroleum
benzin, and carbon bisulphide (distinction from narcotine and co-
deine), but is quite readily soluble in hot amylicalcohol; it dissolves
MORPHINA. 431
freely in dilute acids, in the fixed alkaline hydrates, and in lime-
water, but is almost insoluble in ammonia-water ; its alkaline solu-
tions gradually absorb oxygen and become decomposed, acquiring
thereby a brown color. The aqueous solution oi morphine, and
the alcoholic solution to a still greater extent, possess a bitter
taste and an alkaline reaction.
A solution of morphine in acidulated water, if not too dilute,
affords upon the addition of a solution of potassium or sodium
hydrate, ammonia-water, sodium carbonate or bicarbonate, a white
crystalline precipitate of morphine, which, however, is readily
soluble in an excess of potassium or sodium hydrate, but very
sparingly soluble in ammonia- water; it is not precipitated by tan-
nic acid, but affords a white precipitate with potassio-mercuric
iodide, and a brown one with iodinized potassium iodide.
In addition to the above described characters, morphine may be
recognized and distinguished from all other alkaloids by the fol-
lowing specific reactions and tests:
Strong sulphuric acid dissolves morphine without coloration,
but if the solution be quite strongly heated, and, after being
allowed to cool, a drop of d. luted nitric acid added, the liquid as-
sumes a deep blood-red color; if the solution in sulphuric acid, after
heating and being again allowed to cool, be diluted with water,
and a fragment of potassium bichromate added, an intense ma-
hogany-brown color is produced. With concentrated nitric acid,
morphine produces a blood red color, which gradually changes to
yellow; this coloration, however, is not changed to violet by the
addition of stannous chloride or ammonium sulphide (distinction
from brucine). If morphine or its salts be intimately mixed with
about four times its we ght of cane-sugar, and the mixture added
to concentrated sulphunc ac'd, a dark red coloration is produced ;
if the amount of alkaloid be very small, the mixture will assume
a wine-red or rose-red color. If to a trace of morphine or its
salts a freshly prei)ared solution of molybdic acid or ammonium
molybdate in concentrated sulphuric ac d be added, a fine violet
color is soon produced, which afterwards changes to blue, then to
a dirty-green, and finally disappears ; by the addition of water the
coloration is immediately destroyed. A })articularly character-
istic reaction of morphine or its salts, when free from other
reducing substances, consists in adding a few drops of its solution
to a solution of iodic acid, whereby iodine is liberated, imparting
a yellowish or brownish color to the solution; if then a few drops
of chloroform or carbon bisulphide be added, and agitated with
the liquid, the iod.ne will be absorbed, with a fine violet or purple
color; and by the employment of a few drops of mucilage of
starch instead of chloroform or carbon bisulphide, a fine deep blue
color will be produced. If morphine or a perfectly neutral solu-
tion of one of its salts be brought in contact with a" few drops of a
diluted neutral solution of ferric chloride, a blue color is pro(luced ;
480 MANUAL OP CHEMICAL ANALYSIS.
brown one ; with barium nitrate or chloride it yields a white pre-
cipitate, insoluble in hydrochloric acid.
When a fragment of a crystal of manganous sulphate is heated
with one or two drops of solution of potassium hydrate and a
little jiotassium chlorate or nitrate, upon platinum-foil, it yields a
bluish -green fuse.
Examination :
Ferrous and cupric sulphates are detected, in the diluted solu-
tion, acidulated with hydrochloric acid, the former bv a blue
})recipitate with potassium ferrocyanide, the latter by a reddish-
brown one with the same reagent, or a black one with hydrogen
sulphide.
}fa(/nesium and alkaline sulphates may be detected by com-
pletely precipitating the dilate solution of the salt with ammon'um
sulphide, and by testing part of the filtrate with sodium phos-
phate; a white, crystalline precipitate will indicate mayneshim
sulj^liate : if no reaction has taken place, another portion of the
filtrate is evaporated in a porcelain capsule, and the residue heated
to redness uj)on platinum-foil; a fixed remainder would indicate
jwtassium or sodium salts.
MORPHINA.
MORPHIUM. MORPHINUM.
Morphine. Morphia,
Gcr. Morpliin ; Fr. Morphine ; Sp. Morfina
C^Hj.NOj.n^O ; m^.
Small, brilliant, prismatic crystals, transparent and colorless, or
a wliite, crvstalline powder, containing one molecule (5.94: percent.)
of water of crystallization. When heated to 120^ C. (24?:5® F.),
the crystals lose their water of crystallization and become opaque,
and, when cautiously further heated, thev melt without decom-
position, assuming a crystalline form on cooling; at temj.>eratures
above 200- C. {j^X^l^ F.), they b<?comc decomposed and blackened,
and, when strongly heated on platinum-foil, they burn away, leav-
ing a carbonaceous residue, which is wholly dissipated at a red
heat.
Morphine is but sparingly solul)le in cold water, requiring at
ir)° C. (oDo F.) 1000 parts of the latter for solution, but is soluble
in oOO j)arts of boiling water, in 100 j^arts of alcohol at 15° C.
(59^ F.), and in 8^) parts of boiling alcohol; it is very spanngly
soluble in ether and chloroform, and insoluble in benzol, petroleum
benzin, and carbon bisulphide (distinction from narcotine and co-
deine), but is quite readily soluble in hot amylicalcohol; it dissolves
MORPHINA. 431
freely in dilute acids, in the fixed alkaline hydrates, and in lime-
water, but is almost insoluble in ammonia-water ; its alkaline solu-
tions gradually absorb oxygen and become decomposed, acquiring
thereby a brown color. The aqueous solution of morphine, and
the alcoholic solution to a still greater extent, possess a bitter
taste and an alkaline reaction.
A solution of morphine in acidulated water, if not too dilute,
affords upon the addition of a solution of potassium or sodium
hydrate, ammonia- water, sodium carbonate or bicarbonate, a white
crystalline precipitate of morphine, which, however, is readily
soluble in an excess of potassium or sodium hydrate, but very
sparingly soluble in ammonia- water; it is not precipitated by tan-
nic acid, but affords a white precipitate with potas^io-mercuric
iodide, and a brown one with iodinized potassium iodide.
In addition to the above described characters, morphine may be
recognized ar.d distinguished from all other alkaloids by the fol-
lowing specific reactions and tests :
Strong sulf>huric acid dissolves morphine without coloration,
but if the solution be (juite strongly heated, and, after being
allowed to cool, a drop of d. luted n.tric acid added, the liquid as-
sumes a deep blood-red color ; if the solution in sulphuric acid, after
heating and being again allowed to cool, be diluted with water,
and a fragment of potassium b chromate added, an intense ma-
hogany-brown color is produced. With concentrated nitric acid,
morphine produces a blood red color, which gradually changes to
yellow; this coloration, however, is not changed to violet by the
addition of stannous chloride or ammonium sulphide (distinction
from brucinc). If mor|)hine or its salts be intimately niixed with
about four times its we ght of cane-sugar, and the mixture added
to concentrated sulphuric ac d, a dark red coloration is produced ;
if the amount of alkaloid be very small, the mixture will assume
a wine-red or rose-red color. If to a trace of morphine or its
salts a freshly prepared solution of molybdic acid or ammonium
molybdate in concentrated sulphuric ac d 1x5 added, a fine violet
color is soon produced, which afterwards changes to blue, then to
a dirty-green, and finally disappears; by the addition of water the
coloration is immediately destroyed. A particularly character-
istic reaction of morphine or its salts, when free from other
reducing substances, consists in adding a few drops of its solution
to a solution of iodic acid, whereby iodine is liberated, imparting
a yellowish or brownish color to the solution; if then a few drops
of chloroform or carbon bisulphide be added, and agitated with
the liquid, the iod.ne will be absorbed, with a fine violet or purple
color; and by the employment of a few drops of mucilage of
starch instead of chloroform or carbon bisulphide, a fine deep blue
color will be produced. If morphine or a perfectly neutral solu-
tion of one of its salts be brought in contact with a few drons of a
diluted neutral solution of ferric chloride, a blue color is produced ;
434
MANUAL 07 CHEMICAL AMALT8IS.
curdy precipiiale. insoluble in niiric acid, but soluble iuamtnonia-
water, whiuli fulution, wlien lieated in a test-tube, separates metallit;
silver.
"Wlien a little dry morphine liydroclil orate ia added to n mix-
ture of two paria of ronccntrated sulphuric acid and one part of
water, in a -tmall test-tulic, no change of color of the liquid lakes
place, either at common lemperatures, or when geutly warmed by
immersing the test-tnbe in hot walcr (evidence of the abseuce of
saliuin and other bitter substances) ; when this liquid is'divided
into two portions, and one drop of strong uitrio acid is added to
the one part, a red coloration occurs, and on adding a trace of
potassium bichromate to the other part, only a slight yellowish-
green coloration takes place.
Morphine hydrochlorale dissolves in chlorine- water, with a
yellowish color, which becomes brown upon the addition of am-
monia-water (dislinclion from quinine, wliich yields an emerald-
green color). Ill its general behavior toward re-agents, mor-
phine hydrocliloratc corresponds to the tests for morphine, as
described under the latter, on page -131.
MORPHINE SULPHAS.
MORPHIUM SEU MORPHINUM 8ULFUBICUM.
Sutpliale of iforphint or Morjikia. Morphine Sulphait.
Ger. Sclnverdsnures Miirpliin ; Fr. Sulfalede morphine;
Hp. Sulfate de n)orfin&.
(C„H„N0J,.H,S0,+5H»0; 758.
White, fasciculate, feathery crystals, of a silky lustre, contain-
ing 5 molecules (11.87 per cent.) of water of crystallization, and
permanent in the air. When heated to 130° C. (266° F.), the
salt loses iti; water of crystallization, and. when strongly heated
on platinum-foil, burns entirely away without residue.
Morphine sulphate is soluble iu 24 parts of water and in 702
parts of alcohol at 15° C. (59* F.), and iu about 0.5 part of Iwiliny
water and 31 parts of boiling alcohol (distinction from quinine
sulphate); it iw almost insoluble in ether and in chloroform. Its
aqueous solution is neutral and very bitter; it gives no jierma-
nent precipitate with pntoHsium* hydrate when added in slight
excess, but yields with ummonia-water and the alkaline carbonates
and bicarbonates a white crystalline precipitate of m()rphine. li
aQbrds a blue color with a dilute, neutral solution of ferric chlo-
ride, and a white precipitate, insoluble in acids, with barium
chloride.
Morphine sulphate dipsolves in strong sulpiiuric acid without
MORPHINA. 435
coloration, even when gently warmed by dipping the test-tube in
warm water (evidence of the absence of salicin and other bitter
glucosides) ; it dissolves in concentrated nitric acid with a yellow-
ish-red coloration (distinction from quinine). When dissolved in
a little chlorine- water, morphine sulphate yields a greenish yellow
solution, which becomes dark-brown upon the addition of ammo-
nia-water (further distinction from quinine, which yields an
emerald-green color). In its general behavior toward reagents,
morphine sulphate corresponds to the tests for morphine, as de-
scribed under the latter on page 431.
Examination :
Sodium sulphate^ which has been found to occur as an adulterant
of morphine sulphate, may be detected, as well as other inorganic
salts, by a non-volatile residue, when a little of the morphine
sulphate is strongly heated on platinum-foil.
Amvionium salts may be recognized by the odor of ammonia,
when a little of the salt is heated, in a test-tube, with a strong
solution of potassium hydrate; and by the formation of white
fumes, when a glass rod, moistened with acetic acid, is held over
the orifice of the tube.
fflorphiometrio Assay of Opium :
Since the therai>eutical and commercial value of opium mainly
depends upon the quantity of morphine which it contains, an ex-
amination of opium is invariably required before its introduction
into the market or its application for the manufacture of the
opium alkaloids, or for medication. Among the various methods
for the estimation of the morphine strength of opium, the follow-
ing are simple in execution, require comparatively little time,
and render approximately correct results.
I. Fliicki(/ers Process. — Eight grams of powdered air-dry
opium are digested for twelve hours, with frequent agitat'on, with
80 grams of cold water, and subsequently filtered. 42.5 grams of
the filtrate (representing the soluble matter of one- half of the
opium employed) are then brought into a tared flask, and to the
solution 12 grams of alcohol, of about 0.820 spec, grav., and 10
grams of ether are added, whereby no turbidity should ensue; a
portion of the ether forming a colorless layer on the surface of
the mixture. 1.5 grams of ammonia- water, spec. grav. 0.960, are
then added, and, after thorough agitation, the mixture allowed
to repose for 24 hours, when the morphine will be deposited in
white crystals. The crystals of the alkaloid are afterwards col-
lected on a folded double filter having a diameter of about 10
centimeters (four inches), the flask rinsed with 10 grams of a
mixture of equal parts of alcohol and ether, and finally with 10
grams of pure ether, and these liquids gradually poured on the
crystals of morphine in order to wash them. The crystals are
subsequently cautiously pressed between the folds of the two
filters, which will almost completely absorb the mother liquor
which the crystals of niorpliine may atill relaiu. The alkaloid
may now readily be rt'inoved from the filter, and having been
brought into the tared flank, which may still contain a few crys-
tals of morphine attached to its sides, the whole is dried at HW
C. (212" F.), and its weight determined. From the weight of the
alkaloid, which, at 100^ C. {212'^ F.), corresponds to the formula
C„H,^0,+ H,0, the peroeniage of morphine may be calculalod.
As by the above method u small amount of morphine remains
disHoived in the liquid from which it has separated, the error
which would thereby be occasioned may be eliminated by adding
0.088 gram to the amount of alkaloid obtained. As a lest for
the purity of the crystals obtained, they should, although slowly,
be completely soluble in lOU times their weight of oflicinal lime-
water. An air-dried opium, of good quality, when submitti^ to
the above method of examination, should yield from 0.40 to 0.48
gram of alkaloid, corresponding to from 10 to 12 per cent, of
pure morphine,
II. .Vym'Wff Modijkation i,f Flvcki'jer's Prnrrgs. — Ten gramn
(154.32 grains) of commercial opium, in its moist or powdcj-ed
condition, and representing the average quality of the specimen,
lire brought into a flask or wide-mouthed bottle of 120 cubic
centimeters (4 fluidounces) capacity, which has been previously
weighed and fitted with a good cork : 100 cubic centiraeters {3J1
fluidounces) of water are ihen added, and the mixture well
shaken. It ia then allowed to macerate over night, or for about
twelve hours, with occasional shaking, and then, after shaking well,
the magma is trar.sferred to a tiller of about 10 centimeters (4
inches) diameter, which haf been placed in a funnel and well
wetted.
The solution is now filtered into a tared or marked vessel, and
the residue on the filter percolated with water dropped on to the
edges of the filter and the residue until the filtrate measures about
120 cubic centimeters (4 fluidounces), and this strong solution set
aside. The residue is then returned to tlie flask or bottle by
mcHns of a very small spatula, without breaking or disturbing
the filter in the funnel, 80 cubic ccntimetcrB {1 fluidounee) of
water added, the mixture well shaken, and the inagma returned
to the filter. After being allowed to dr.iin, the bottle is rinsed
twioe, each time with H' cubic centimeters (0.33 tluidounce) of
water, and the rinsings poured upon the residue. When this has
passed through, the filler and residue are washed with 20 cubic
centimeters (0,66 fluidounce) of water, applied drop by drop
iironnd the edges of the filler and upon the contents. This
(lli()-l-70) 190 cubic centimeters (6,33 fluidounces) of total solu-
"1 practically exhaust almost any sample of 10 grama of
ally B pai
)riginally i
drying become hard and flinty, '
opium; but occasionally n particularly rich opium, or one
flonrHO powder, or an originally moist opium which
will
requii
: further *
by slow
haustion.
MOKPHINA. 437
In all such cases, or cases of doubt, the residue should be again
removed from the filter and shaken with 30 cubic centimeters (1
fluidounce) of water, and returned and again washed as before.
The filter and residue are now dried at 100° C. (212^ F.) until
they cease to lose weight; and if any residue remains in the bot-
tle, the bottle is also to be dried in an inverted position, and
weighed. The weaker solution is then evaporated in a tared
capsule of about 200 cubic centimeters (6.6 fluidounces) capacity,
without a stirrer, on a water-bath, until reduced to about 20
grams (309 grains), the 120 cubic centimeters of stronger solution
subsequently added, and the whole again evaporated to about 20
grains (309 grains). The capsule and contents are cooled, and,
when cool, 5 cubic centimeters (0.17 fluidounce) of alcohol, spec.
grav. 0.820, added, and the mixture stirred until a uniform solu-
tion is obtained and no adhering extract remains undissolved on
the capsule. If this solution should contain an appreciable pre-
cipitate, it must be filtered, the filter carefully washed, and the
filtrate evaporated to 25 or 30 grams. The concentrated solution
from the capsule is poured into a tared flask of about 100 cubic
centimeters (3.33 fluidounces) capacity, the capsule rinsed with
about 5 cubic centimeters of water, used in successive portions,
and the rinsings added to the contents of the flask. If the solu-
tion has not required filtering, then 5 cubic centimeters (0.17
fluidounce) more of alcohol are added: if it has been filtered and
evaporated, 10 cubic centimeters (0.33 fluidounce) of alcohol are
added and shaken well. Then 30 cubic centimeters (1 fluidounce)
of ether are added, and again shaken well. Four cubic centi-
meters (0.133 fluidounce) of ammonia- water, spec. grav. 0.960, are
now added, the flask shaken vigorously until the crystals begin
to separate, then set aside in a cool place for 12 hours, that the
crystallization may be completed.
The ethereal stratum is poured oflf from the flask, as closely as
possible, on to a tared filter of about 10 centimeters (-1 inches)
diameter, which has been well wetted with ether, 20 cubic cen-
timeters (0.66 fluidounce) of ether added to the contents of the
flask, which is rinsed around without shaking, and the ethereal
stratum again poured off as closely as possible on to the filter,
keeping the funnel covered. When the ethereal solution has
nearly all passed through, the edges and sides of the filter are
washed with 5 cubic centimeters C0.17 fluidounce) of ether, and
the filter allowed to drain with the cover off. The remaining
contents of the flask are then placed on the filter, and the funnel
covered. When the liquid has nearly all passed through, the
flask is rinsed twice with two portions of water of 5 cubic cen-
timeters (0.17 fluidounce) each, pouring the rinsings with all the
crystals that can be loosened on to the filter, the flask dried in an
inverted or horizontal position, and, when thoroughly dried,
weighed. The filter and crystals are then washed with 10 cubic
438 MANUAL OF CHEMICAL ASALTSCS.
ueitti meters (0.33 fluidouuce) of water, applied drop h\' drop to
the edgea of the filter, and, when drained, the filter and con-
tents removed from the funtiel, the edges of the tllter oloited
together, and the filter compressed gently between many folds of
bibulous paper. It is then dried at 100^ C. (212" F.) and'weighed.
the cryfitals of morphine removed fn)m the filter, and the latter
brushed otl' and reweighed. to get the tare to be subtracted. The
remainder, added to the weight of the crystals in the dusk, will
give the total yield of morphine, in elean, distinct, small, light-
brown crystals. As a test of purity for the obtained morphine.
0.1 gram of the finely powdered cryi<tal8 should be eomplelely
soluble in 10 cubic centimeters of officinal lime-water.
Ill, United Slates Pharmacopeein Process. — Seven grams of
opinin (in any condition to be valued) arc triturated, in a mortar,
with '6 grams of freshly slaked lime and 20 cubic centimeters of
distilled water, until a uniform mixture results, after which 50
cubic centimeters of distilled water are added, and the mixture
stirred occasionally during half an hour. It is then tillered
through a plaited filter, having a diameter of 75 to 90 millimeters
(3 to 3.5 mches), into a wide mouthed bottle or stoppered flask
(having a capacity of about 120 cubic centimeters and marked at
50 cubic centimeters) until the filtrate reaches this mark. To the
filtered liquid (representing 5 grams of opium) 5 cubic centimeters
of alcohol and 25 cubic centimeters of stronger alcohol are added,
and, after shaking the mixture, 3 grams of ammonium chloride
are added, the mixture again shaken well and frequently during
half an hour, and then set aside for twelve hours. After coun-
terpoising two »niall filters, one is placed within the other in a
small funnel, and the ethereal layer decanted as completely as
practicable upon the filter. Ten cubic ceniimetors of stronger
ether are then added to the contents of the bottle and the mix-
ture rotJited, the ethereal layer again decanted upon the filter,
and the latter afterward washed with 5 cubic centimeters of
stronger ether, added slowly and in small portions. The filter is
now allowed to dry in the air, and the liquid in the bottle poured
upon it, in portions, in such a way as to transfer the greater por-
, tion of the crystals to the filter. The bottle is then washed, and
the remaining cryslak transferred to the filter, with several small
portions of distilled water, using not much more than 10 cubic
centimeters in all, and distributing the portions evenly upon the
filter. After allowing the filter to drain, it is dried, first by press-
ing it between sheets of bibulous paper, and afterward at a lem-
)>erature between 55 and 60° C. (131 to 140° ¥.). The crystals in
the inner filter are now weighed, using the outer filter as a ooun-
terpoiso. The weight of the crystals in grama, multiplied by 20,
represents the percentage of morphine in the opium employed.
The U, S. Pharmucojiotia directs that opium, in its normal,
moist condition, should yield not less than 9 |jer cent, of mor-
NICOTINA. 439
phine; and powdered opium not less than 12 nor more than 16
per cent, of morphinej when assayed by the above prt)cess.
Horphiometrlo Assay of Tincture of Opium :
When tincture of opium has to be examined for the quantity of
morphine it contains, this may be ascertained by either of the
following methods:
I. To forty grams of the tincture (corresponding to 4 grams of
powdered opium when prepared according to the United States
and German Pharmacopoeias), contained in a tared flask, 1.5 cubic
centimeters of ammonia-water, spec. grav. 0.960, and 13 cubic
centimeters of ether are added; after being well mixed by agita-
tion the mixture is allowed to repose for at least thirty-six hours,
when the crystals of morphine may be collected and further
treated as described under Fliiokiyer's morphiometric process on
page 435.
To the amount of alkaloid obtained from the stated amount of
tincture, about 0.1 gram should be added, as representing approxi-
mately the amount of morphine remaining dissolved in the liquid
from which it has been precipitated. Ttie total weight of alka-
loid should be not less than 0.48, nor more than 0.64 gram, indi-
cating the employment of an opium containing not less than 12,
nor more than 16 per cent, of morphine.
II. One hundred and twenty cubic C3ntimeters (4 fluidounces)
of the tincture, or other liquid preparations, are evaporated at a
low temperature to 10 grams (155 grains), and the process then
conducted exactly as described under Squihb^s modified method
of assay, on page 436, using, however, 5 cubic centimeters of alco-
hol, instead of 10, and 2.5 to 3 cubic centimeters of ammonia-water,
instead of 4 cubic centimeters.
NICOTINA.
NICOTINUM.
Nicotine, Nieotia.
Ger. Nicotin ; Fr. Nicotine ; 8p. Nicotina.
C.,H,,N,; 162.
A colorless or nearly colorless, oily, and volatile liquid, having
the specific gravity 1.027 at 15° C. (59^ F.), a pungent odor, re-
sembling that of tobacco, and an acrid, burning taste. By expo-
sure to the air, it becomes gradually brown and thick; it begins
to volatilize at 146° C. (294.8° F.), and boils in an atmosphere of
hydrogen at from 240 to 242° C. (46i to 467.6° F.); when heated
on platinum-foil it volatilizes completely, forming irritating
vapors, which readily take fire, and burn with a bright, sooty
440 MANUAL OP CHEMICAL ANALYSIS.
jljiine. AVlien dropped into concentnited sulphuric acid, it dis-
solves, with a red color, and, when one drop of solution of potas-
sium bichromate is added, the solution becomes brown, and
subsequently green; when mixed with hydrochloric acid and
cautiouslv warmed, a reddish-brown mixture is formed, which, bv
further evaf)t)ration and cooling, yields, upon the subsequent ad-
dition of nitric acid, a violet coloration, gradually changing to
orange.
Nicotine produces while fumes with hydrochloric and acetic
acids, precisely like ammonia-water; it sinks when dropj>ed into
water (distinction from coniine, which floats), but is miscible with
water in all pro|)ortions, and becomes again separated on the
addition of solid jK)tassium or sodium hydrate: it also dissolves
in alcohol, ether, amylic alcohol, carbon bisulphide, chloroform,
petroleum bcnzm, and in most of the lixed and volatile oils; its
solutions have an alkaline reaction, and an acrid, burning taste;
they produce precipitatesinsolutionsof neutral and basic plumbic
acetate, cupric acetate, and many other metallic salts, and are pre-
cipitated by solutions of tannic acid, potassio- mercuric iodide,
i<xlinized potassium iodide, and auric and platinic chlorides, but
the aqueous solution alVords no precipitate with chlorine-water
(additional distinction from coniine); the alcoholic solution should
yield no turbidity with diluted sulj>huric acid (evidence of the
absence of ammonia). The aqueous solution of nicotine, when
applied to the eye, causes the pupil alternately to dilate (mydri-
asis) and to contract ^^stenocoriasis).
By careful oxidati*m with concentrated nitric acid or potassium
permanganate, nicotine is converted into uicofinic acidy C^H^XO,
^Pyridine-earbonic acid, CjII^N-COOH), which may be obtained
from its silver salt by decomposing it with hydrogen sulphide.
Nicotinic acid forms colorless, needle-shaj)ed crystals, which are
readilv soluble in alcohol and in boiling water, but not in cold
water or in ether: they melt at 22.") C. (4o7° F.\ and, when heated
with soda-lime, yield the volatile organic base, pf/ridine, C^H^N.
For the separation <^f nicotine from other alkaloids, or from
e.omplex organic mixtures with which it may be associated, see
page UV"^.
OLEUM AM7GDAL2S ^STHBREUM.
OLKUM AMY(;i)ALAUrM AMARAUUM .ETHEREUM.
VohtWf Oil of BitUr Afmond.
Gor. HitlormaiidoU)! ; Fr Essence iramandes ameres ;
Sp. Emmic'ih lie nlnu'iidrus amargas.
A tliin, colorless, or golden-yellow liquid, of great refractive
power, anvl of the odor of bitter almonds. Exposed to the air, it
OLEA. 441
rapidly absorbs oxygen, with the formation of crystals of benzoic
acid; its spec. grav. is from 1.060 to 1.070 at 15^ C. (59° F.): or,
after the removal of the hydrocyanic acid, 1.043 to 1.049 ; its
boiling-point, 180° C. (356^ *F.).
When dropped into water, oil of bitter almonds sinks, but dis-
solves upon shaking, unless too much oil has been used, about 300
parts of water being required for solution. When a few drops of
solution of potassium hydrate are added to its aqueous solution,
and afterward one or two drops of a solution of a ferrous and a
ferric salt, and finally, after agitation, a slight excess of hydro-
chloric acid, there will appear a blue coloration, and, after a while,
a blue precipitate.
Oil of bitter almonds is miscible, in all proportions, with alco-
hol, ether, chloroform, carbon bisulphide, and essential and fatty
oils; it is also soluble in concentrated nitric acid, without color,
and without the evolution of nitrous fumes ; with an equal volume
of concentrated sulphuric acid the mixture assumes a red color,
which gradually increases in intensity, but remains limpid and
clear.
Oil of bitter almonds consists essentially of benz-aldehyde, or
the aldehyde of benzoic acid, C^H,-COH, together with usually
from 2 to 5 per cent, of hydrocyanic acid, which, in the process
of distillation, combine to form a very unstable compound. From
this compound the acid is gradually liberated, and becomes j)ar-
tially converted, by its decomposition, into ammonium cyanide
and formic acid. The crude oil, obtained by distillation without
further rectification, usually contains the largest proportion of
hydrocyanic acid.
Examination :
Alcohol may be detected in oil of bitter almonds by agitating it
with three times its volume of concentrated nitric acid, and sub-
sequently warming the mixture by dipping the test-tube into hot
water. No reaction takes place with pure oil ; but, if it has an
admixture of more than three per cent, of alcohol, effervescence
will occur, with disengagement of yellowish nitrous vapors.
Chloro/orvij as well as alcohol^ can be detected by submitting a
small portion of the oil to distillation from a water-bath, cooling
the receiving test-tube in ice-water (Fig. 139). The boiling-
point of the oil being at 180° C. (3o6° F.), only admixtures vola-
tile at or below the boiling-point of water will distil, with but
small traces of the constituents of the oil. The obtained distillate
is mixed with a little icxline water; if chloroform be present, and
no alcohol, it will absorb the iodine, and se{)arate, with a rose-
color. The colorless, aqueous liquid is decanted, and then warmed
by dipping the test-tube in warm water ; one drop of solution of
iodinized potassium iodide is added, and then one drop of solu-
tion of potassium hydrate, or sufficient nearly to decolorize the
liquid. If alcohol be present, minute yellow crystals of iodoform
442 manoal of chemical analysis.
will bo [troduccd (Fig. 140), which, after aubsidiog,
glass, may be recognized by the examinatiuii of the seJimeiit
uuder the inioroscope.
Fig. 140.
Nilrobensol may be detecied by .idding In drops of the oH
tnixiure of o cubic centimeters of alcohol and an equal volume ol
water, in a narrow test tube, cloaiag the
tube with the finger, and effecting the mix-
ture by gently inverting the tube. If tlie
oil is pure, a perfectly clear solution will
lit once be produced, whereas, if it contains
but one per cent, of nitrobenieol, the liquid
will appear turbid from the separation of
oily drops, which, upi)ii gentle agitation,
aggregate, and are deposited at the bottom
of the lube.
Another reliable test consists in adding
to a portion of the oil, in a test-tube, a few
fragments of metallic zinc, and a little diluted sulphuric acid.
After standing for a couple of hours, or until the evolution of gas
has ceased, the aqueous liquid is filtered through a wet filter, and
to the filtrate a fragment of potassium chlorate and a drop of cod-
centrated sulphuric acid are added; no coloration should be
thereby produced ; a violet color would indicate the proaenoe of
nitrobenzol through it« reduction to aniline.
Essential Oils. — Adulteration with cheaper essential oils, aa
well as with nitroben?/)), may be detected by the property of oU
of bitter almonds to dissolve in a concentrated aqueous solotion
of sodium bisulphite when added drop by drop and agitated;
whereas such admixtures remain undissolved, 6oating upon the
aqueous solution after dilution with a little tepid wat«r.
■ i_
OLE A. 443
Estfanation of the Available Quantity of Hydrocyanic Acid in Oil
•f Bitter Almonds :
I. Five grams of the oil are mixed, in a beaker, with about 25
cubic centimeters of strong alcohol ; then about 200 cubic cen-
timeters of water and a few drops of solution of sodium chloride
are added, and subsequently sufficient of a solution of potassium
hydrate to render the liquid alkaline to test-paper. A decinormal
solution of argentic nitrate (page 98) is then allowed to flow into
the liquid from a burette until, with constant stirring, the pre-
cipitate ceases to be re-dissolved, and therefore a slight j^rmanent
turbidity occurs. The number of cubic centimeters of argentic
nitrate solution employed, multiplied by the decimal 0.0054, will
represent the amount of -hydrocyanic acid contained in 5 grams
of the oil, and has only to be subsequently multiplied by 20 to
express the percentage.
II. Another method consists in adding to 1 gram of the oil,
contained in a small flask, about five times its weight of strong
alcohol, subsequently 45 cubic centimeters of distilled water, and
finally a solution of 1 gram of pure crystallized argentic nitrate
in an excess of dilute ammonia- water. The mixture is well agi-
tated for a few moments, and subsequently pure nitric acid added
until it acquires a slight acid reaction. The precipitated argentic
cyanide is then carefully collected on a tared filter, thoroughly
washed, and finally dried at 100^ C. (212° F.) until of constant
weight. The weight of dry argentic cyanide, when divided by 5,
will represent the amount of hydrocyanic acid in 1 gram of the
oil, and has, therefore, only to be subsequently multiplied by 100
in order to express the percentage.
OLEUM SINAPIS iBTHEREUM.
OLEUM SINAPIS VOLATILE.
Volatile Oil of Mu»tard,
Ger. ^therisches Senfol ; Fr. Huile de moutardc ; Sp. Aceite esencial
de mostaza.
C,H,NS = (CS=N-C3H,); 99.
A colorless or pale-yellow liquid, of a most penetrating, pun-
gent odor, and having the specific gravity 1.017 to 1.021 at 15^ C.
(59^ F.); it boils at 148° C. (298.4° F.). When dropped into
water, it sinks slowly, and dissolves in from 100 to 250 parts of
it, the solubility of the oil in water apparently increasing with
age ; if to the aqueous solution a few drops of solution of argentic
nitrate be added, and heated, a black precipitate of argentic sul-
phide will be produced.
444 MANUAL OF CHEMICAL ANALYSIS.
Mustard oil is miscible with alcohol, ether, chloroform, carbon
bisulphide, and benzol, and with fatty and essential oils ; it suffers
decomposition with concentrated nitric acid, with the evolution of
nitrous vapors, and the formation of a resinous residue. When
dropped into concentrated sulphuric acid, mustard oil dissolves,
without color, and without the evolution of heat, and when
mixed with concentrated sulphuric acid, in the proportion of one
part of oil to three parts of acid, being careful that the mixture is
kept cool, sulphurous acid is evolved, and, after twelve hours, a
colorless or but slightly brown, thick liquid or crystalline mass
is formed, devoid of the odor of mustard oil.
If 2 parts of mustard oil, 1 part of alcohol, spec. grav. 0.830,
and 7 parts of ammonia- water, spec. grav. 0.960, be digested for
several hours at a temperature of about 40° C. (104° F.), and
subsequently concentrated on the water-bath, it is converted into
ihiosinaimnine^ C^HgN,S :
C,H,-CNS + NH, = C,H,N,S.
The latter forms colorless and odorless, shining crystals, which
possess a bitter taste, dissolve readily in water, alcohol, and ether,
and fuse at 74° C. (165.2° F.).
Examination :
Admixtures of essential and fatty oils^ carbon bisulphide^ nitro-
benzol^ and alcohol^ are indicated by becoming warm and dark-
colored when about five or six drops of the oil are added to about
i)0 or 60 drops of concentrated sulphuric acid, in a dry test-tube;
this is particularly the case when a mixture of 8 parts of con-
centrated sulphuric acid and one part of nitric acid is employed,
being careful in the operation of mixing the acids to avoid eleva-
tion of temperature.
If an admixture of carbon bisulphide, chloroform, etc., is sus-
pected, advantage may be taken of their relatively low boiling-
|)oints, and their se[)aration from the mustard oil effected by
distillation from the water-bath ; to the distillate the respective
special tests of identity, as described on pages 302 and 309, may
then be applied.
Admixtures of alcohol,, hctizol^ and other hydrocarbons, are also
indieated when two or three drops of the oil are allowed to fall
into a test-tube, about one-third filled with cold distilled water;
the oil should sink slowly to the bottom, remaining clear and
transparent, until, after gently inclining the tube two or three
times, it becomes opalescent. When contaminated with only a
few per cent, of the above adulterations, the drops lose their
transparency, and become opalescent, as soon as they fall into the
water.
Phenol (carbolic acid), (jaultheria oily and other similar bodies
may readily be detected in the dilute alcoholic solution of the oil
PHOSPHORUS. 445
by the production of a violet color on the addition of a drop of
solution of ferric chloride, whereas pure mustard oil remains
unchanged.
PHOSPHORUS.
Phofphorv$,
Ger. Phosphor ; Fr. Phosphore; Sp. F68foro.
P; 31.
A translucent, slightly yellowish or nearly colorless solid, of a
waxy lustre, and occurring usually in the form of cylindrical
sticks. At ordinary temperatures it has about the consistence of
wax, and may be easily cut with a knife, but at low temperatures
is hard and brittle. It has a distinctive and disagreeable odor
and taste, and the specific gravity 1.82U at 10^ C. (50° F.); it
melts at 44® C. (111.2^ F.), forming a colorless or slightly yellow,
strongly refractive liquid, which has the sf>ecific gravity 1.764; it
boils in an atmosphere free from oxygen at 290*^ C. (554° F.),
yielding a colorless vapor, but is slowly volatilized even at ordi-
nary temj)eratures.
Phosphorus is nearly insoluble in water, but dissolves in 350
parts of absolute alcohol at 15° C. (50° F.), in 240 parts of boiling
absolute alcohol, in 80 parts of ether, in about 50 parts of fatty
oil, and very abundantly in carbon bisulphide; the latter dis-
solving twenty times its weight of the substance, forming a color-
less solution, which, however, requires to be handled with the
utmost caution, as a single drop of it, when allowed to fall upon
paper, soon bursts into flame.
when exposed to the air, phosphorus emits white fumes, which
are luminous in the dark, and have an odor somewhat resembling
that of garlic; it is very inflammable, and must, therefore, be
preserved under water in a cool place. It possesses strongly re-
ducing properties, sepfirating many metals, copper, lead, silver,
etc., from solutions of their salts; by the action of direct sunlight,
or by heating to 250° C. (482° F.), it is principally converted into
the red or amorphous modification, which, among other characters,
is distinguished from ordinary phosphorus by its insolubility in
carbon bisulphide and other solvents, its unalterability by expo-
sure to the air at ordinary temperatures, and its non-luminous
and non-poisonous properties.
By treatment wijth nitric acid, phosphorus is converted into
tri-basic or orthophosphoric acid.
Exuninatioii :
Arsenic and Sulphur. — Commercial phosphorus from its method
of manufacture frequently contains small amounts of arsenic and
446
NUAL OP CHBMtCAL ANALYSIS.
sulplnir, which, however, should not be preseni lo any consider-
able extent. They may be recognized,and, if required, the umount
■ qiiBDtitativelv deteriuined, by the following method. 1 part of
phosphorus ih digested with a mixture of from 6 to 8 parts of
nitric acid and 6 parts of distilled water until it is cotnptetely
dissolved. The solution is then evaporated until nitrous vapors
eease to be evolved, subsequently diluted with water so as to
weigh about 12 parts, and, being heated to about 70" C. (158° F,),
hydrogen sulphide passed through the liquid for about half ao
hour, and finally, alter the removal of tbe heat, until the liqnid
cools. The liquid is then set aside in a tightly corked flask for
twenty-four hours, when any arsenic present, which should not
be more than a trifling quantity, will become precipitated as yel-
low arsenic trisulphide. If the amount uf the latter is to be
quantitatively determined, it may be collected on a tared filter,
washed first with water, and, after drying, with pure carbon bisul-
phide, in order to remove adheriug sulphur, then dried at 100° C.
(212° F.), find 6nally weighed; 100 parts of arsenic Iri.sutphide,
A9,S„ correspond to 61 parts of metallic arsenic. Or the arsenic
trisulphide may be converted into arsenic acid, by treatment with
hydrochloric acid and a little potassium chlorate on the water-
bath, and, by the addition of test magnesium mixture, precipitated
as ammonio-magnesium arscniate; the latter, when collected on
a tared filter, washed with dilute ammonia- water, and dried at
105" 0.(221" F.), corresponds to the formula MgNH,AsO,-|- JH,0,
and of which 1IX> parts correspond to 39.47 parts of metallic
The tiltrate from the original precipitate of arsenic trisulphide
when tested with solution of barium chloride should not afford
more than a slight opalescence ; a white precipilate, insoluble in
hydrochloric acid, will reveal the presence of sulp/iur, which, by
the above Ireatment with nitric acid, becomes converted into
sulphuric acid.
Separation and Deteotion of Fhosphoms In Forensic Invest^a-
tiODB. — Incoiisidcratinu of tiie extensive application of pliosphorns
in the preparation of lucifer malches, and of its employment in
the form of a paste for the destruction of vermin, it is occasionally
the object of search in cases of accidental or criminal poisoning,
and a convenient and reliable method for its isolation and detection
will therefore be briefly described.
The substance under examination, which may consist of some
article of food, the contents of a stomach, vomited matters, elc^
is first examined by its odor, which will frequently reveal the
presence of phosphorus, when existing in the free state. As a
preliminary test^ the substance is then brought into a glass flask,
provided with a tightly tilting cork, and a small strip of paper
moistened with a solution of iirgenlic nitrate suspended from the
oork, so as to project .slightly into the interior of the flask. Siil-
IL
PHOSPHORUS. 447
■
•
ficient water is then added to the mixture to form a thin liquid,
and also a little tartaric acid, in order to insure a distinctly acid
reaction, after which the contents of the flask are very gently
heated. If phosphorus be present, the paper moistened with the
silver solution will become blackened, either immediately or after
standing for a few hours, in consequence of the slight volatiliza-
tion of the phosphorus and the formation of argentic phosphide.
As, however, the material under examination might also contain
putrefying matters, accompanied by the development of hydrogen
sulphide, etc., which would likewise cause a blackening of the
silver paper, the precaution should be observed to insert in the
cork of the flask, together with the silver paper, a small strip of
paper moistened with a solution of plumb'c acetate. If the latter
remains unaffected, whilst the silver paper becomes blackened, the
presence of phosphorus is rendered highly probable.
In addition to the above-described preliminary test, the lumi-
nosity of phosphorus in the dark affords the most striking and
conclusive proof of its presence in the unoxidized state, and the
substance should, therefore, invariably be further examined by
the following method, which depends upon the volatilization of
phosphorus with aqueous vapor, and the luminosity of the vapor
when observed in the dark.
The material under examination, acidulated with tartaric acid,
and contained in the flask A (Fig. 141), is gradually heated to the
boiling-point of the liquid, and the vapors conducted by means of
the bent glass tube, />, />, into the tube, rf, rf, of a glass condenser,
By which is maintained in a vertical position by the stative. I),
The condenser is kept cool by a current of water flowing from a
through the rubber tubing into the funnel-tube, c, and passing
out through the rubber tubing, e, whilst the flask, (7, serves for
the reception of the distillate.
In the presence of prdinary phosphorus, and by conducting the
distillation in a dark room, a luminous ring, which remains visible
for a considerable time, will be observable in the cooled portions
of the tube, d, d, while if considerable phosphorus be present,
small particles of the latter will also frequently be found in the
distillate. It should, however, be considered that the presence of
alcohol and ether, as also of volatile oils, retard or prevent the
luminosity of the vapor, but, as soon as these are volatilized, the
characteristic reaction may at once be observed. If a quantita-
tive determination of the i)hosphorus be required, the distillate,
together with any particles of suspended phosphorus which it may
contain, is mixed with a sufficient amount of good chlorine-water,
and, after being allowed to stand for about twelve hours, evapo-
rated to a small volume upon tlie water-bath. The phosphorous
acid of the distillate is thereby converted into phosphoric acid,
and, after supersaturation with ammonia-water, may be precipi-
tated by test magnesium mixture as ammonio-magnesiuiu phos-
NUAL OP CHEMICAL AN
pliflte; the latter is then colieeied uj on a filter, -wai
iillie dilute ammoBia-waler, dritd, and bv ignition in a small
poroelain crucible, converted into magnesium pyrophospliate,
Mg,P,0„ and its weight finally determined: 100 parts of the
latter compound correspond to 27.y2 parts of pliosphorun.
If in the above-described method for the detection of pboe-
phorus it should also be necessarv or desirable to take into con-
sideration the possible prcsencr of hydrocyanic acid, the Bame
method i>f investigation may be pursued, reserving, however,
the first portion of the distillate for examination for hydrocyanic
acid, as described on page 162, or for other readily volatile sub-
stances by which it may be accompanied. The subsequent por-
tion of the distillate may then be employed for the qualitative or
Quantitative determination of phosphorus, in the manner above
escri bed.
PICROTOXINUM. 449
FH7SOSTIGMIN21 SALIC7LAS.
PUY808TIGMINUM 8ALICYLICUM.
Salicylate of Physoatigmine, Phy$oiUgmine Salicylate.
Ger. Salicylsaures Physostigmin ; Fr. Salicylate de physostigmioe ;
Sp. Salicilato de fisostigmina.
C„H„N30,.C,H.03 ; 413.
Colorless or faintly yellowish, shining, acicular, or short colum-
nar crystals, which by long exposure to air and light gradually
assume a reddish color; when strongly heated on platinum-foil
they are completely dissipated.
Physostigmine salicylate is soluble in 130 parts of water and
in 12 parts of alcohol at 15^ C. (59^ F.) ; in 30 parts of boiling
water, and very freely in boiling alcohol. The aqueous solution
is neutral in its action upon litmus, and possesses a bitter taste ;
it is precipitated by the ordinary alkaloidal reagents, is rendered
turbid by iodine-water, and yields with a drop of a dilute solution
of ferric chloride a violet coloration ; upon exposure to diffused
light for one or two days it assumes a reddish color. The solu-
tion of the salt in concentrated sulphuric acid is at first colorless,
but afterwards assumes a yellow color. If sodium bicarbonate
be added to the aqueous solution of the salt, which is afterward
shaken with ether, and the ethereal solution separated and allowed
to evaporate spontaneously, an amorphous residue of physostig-
mine is obtained ; the latter possesses a decidedly alkaline reaction,
fuses at 45^ C. (113° F.), ana its aqueous solution, on exposure to
the air, soon becomes red, or sometimes intensely blue, resulting
from its partial decomposition; if sulphurous acid be added to
such a solution, the color is discharged, but returns again on the
evaporation of the acid. On concentrating the aqueous solution,
which has been precipitated by sodium bicarbonate and shaken
with ether, to a small volume, and supersaturating with sulphuric
acid, a bulky white precipitate is obtained, which responds to the
reactions of salicylic acid, page 181.
A solution of physostigmine, or any of its salts, when applied
to the eye, strongly contracts the pupil.
PICROTOXINUM.
Picrotoziii,
Ger. Pikrotoxin ; Fr. Picrotoxine ; Sp. Picrotoxioa.
C,H,,0,; 182.
Colorless, shining, prismatic crystals, which undergo no change
bv exposure to the air; they are odorless, possess an iDtenseK'
29
450
MATCCaL of CBSHICAL AXALTStS.
bitter taste, and are nentral ta their action apaa Ktnos. On
being heated to about 21)0° C. (395- F .) the crystals melt lo a yel-
low liquid; when heated od plalitiaDi-fotl they char, ami at a
atrotig heat are finally comi'leiely dissipated.
Picrotoxin is scilahle in 150 parts of water and 10 parta of alco-
hol at 15= C. (59'^ F.), in 25 parts of boiling water aod 3 parts of
boiling alcohol; the latter solntion forming upon cooling a mass
of silky prisms. It is abo soluble in about 2.5 parts of ether, and
readily in amylic alcohol and chloroform ; conoeotnited aoetic
acid hkewise dissolvea it, as do also the fixed alkalies and ammo-
nia-water, and from the latter solutions it is precipitated unehangod
on the addition of an acid.
If a little picrotoxin be placed in a capsate and mixed with four
or five drops of concentrated Bulphuric acid, the crystals dissolve
with a golden-yellow color, which changes to salTroD-yellow; on
subsequently adding a trace of powdered potassium bichromate, a
violet-green color is produced, and, upon dilution with wat«r, a clear
yellow ish-green solution is formed. When a little picrotoxin ia
intimately mixed with 3 or 4 times its weight of pota^ium nitrate,
and the mixture moistened with sulphuric acid, no change ts
observed, but on subsequently adding sufficient of a solution of
potaissium or sodium hydrate to impart a strongly alkaline
reaction, it assumes an evanescent brick-red color.
Tlie aqueous solution of picrotoxin, to which a few drops of a
dilute solution of potassium or sodium hydrate have been added,
reduces an alkaline solution of cupric tartrate on warming; in
this respect resembling a solution of grape-sugar and many other
indifferent organic substances, although its reducing pru)>erties
are inferior in extent. It also resembles a solution of grapo-
sugar in that its alkaline solution becomes decomposed on worm-
ing; the solution becoming at first yellow, and then brick-red.
Picrotoxin being a perfectly neutral principle, and devoid of
nitrogen, its solution is not affected by solutions of the salts of
platinum, gold, and mercury, or by potaasio-merruric iodide, tan-
nic acid, or other alkaloids! reagents, which thus distinguishes it
iVom and indicates the absence of alkaloids. It is absorbed by
ether from its acidulated aqueous solution, and may thus be sepa-
rated from alkaloids and other complex organic principles with
which it may be associated, us described on page 106.
This lool is the prOf.
COOPER MEDICAL CO.'.,
&M4 nUNCISCC. OAL.
tmd i* not t" !f r.".i" ■'/,'"
PIPERITA. 451
FILOCARFIN^l H7DROCHLORA8.
PILOCARPINUM HYDHOCHLORICUM SEU MURIATICUM.
ffydrochlorate of Pilocarpine. Pilocarpine Hydrochlorate,
Ger. Salzsaures Pilocarpin ; Fr. Chi nrliyd rate de pilocarpine ;
Sp. Hidroclorato de pilocnrpina.
C„H„N,0,.HC1 ; 244.4.
Small, colorless, deliquescent crystals, without odor, but pos-
sessing a slightly bitter taste. When heated on platinum-foil
they first melt, and at a strong heat are finally completely dissi-
pated.
Pilocarpine hvdrochlorate is readily soluble in wjiter and in
alcohol, but almost insoluble in ether, chloroform, benzol, and
carbon bisulphide. The aqueous solution is neutral in its action
upon litmus, and possesses a slightly bitter taste ; when slightly
acidulated it is not precipitated by ammonia-water, and solution
of sodium hydrate produces only in a concentrated solution of the
salt a slight turbidity; with solution of argentic nitrate the
aqueous solution yields a white precipitate, which is insolu-
ble in nitric acid, but soluble in ammonia water. With concen-
trated sulphuric acid the crystals of the salt yield a yellow, with
nitric acid, spec. grav. 1.4, a faintly greenish-violet, and with sul-
phuric acid and potassium bichromate an emerald-green color.
An aqueous solution of pilocarpine, or any of its salts, when
applied to the eye, strongly contracts the pupil.
PIPBRINA.
Piperine,
Ger. Piperin ; Fr. Piperine ; Sp. Pipcrina.
C,,H„X03; 285.
Colorless, or sliglitly yellowish, shining, four-sided prisms, be-
longing to the rhombic system, and permanent in the air; they
are neutral in their action upon litmus, odorless, and almost taste-
less when first placed on the tongue, but by prolonged contact
produce a sharp, biting sensation. When heated to about 128^
C. (262^ F.), they melt to a clear, yellowish liquid, which, on cool-
ing, congeals to a resinous mass ; at a higher temperature they
are de«x)mposed, and, when strongly heated on platinum-foil,
they take fire, and are finally completely dissipated.
Piperine is almost insoluble in ,eUh.er cold or hot water ; it is
soluble in 30 parts of alcohol at 15/' C! (o9^ F.\ in 1 part of boil-
ing alcohol, and slightly soluble in*ether,-eh1oroform, benzol, and
the volatile oils.
452 MASIAL OF CHEMICAL ANALYSIS.
Concentrated siilphurio acid dissolves piperine willi a dark
blood-red color, wbich disappears on dilution with water. When
treated with cold concentrated nitric acid it assumes a greeniah-
yellow color, which rapidly changes to orange and red, and gradu-
ally dissolves with a reddish color ; on adding to this solution un
excess of solution of potassium hydrate, the color in nt 6rsL pale
yellow, but, on boiling, it deepens to blood-red, while at the same
time vapors of an alkaline reaction and of a peculiar odor (pii>e-
ridine)are given off. On heating with soda-lime, or by prolonged
boiling w,lh an alcoholic solution of potassium hydrate, pipcrin is
converted, by the absorption of a molecule of water, iato pijieri-
Hine, C,H„N, and crystallizable pijitric odd, C„H,jO^:
C„H„NO, ■\- HP = C.H„N + C„H„0,.
Piperidine is a clear colorless alkaloid, having the odor of pep-
Kr and ammonia, and possessing strongly basic properties; it
ilfl at 106" C {222.S° F.), is soluble in all proportions in water
and alcohol, and combines with acids to form well crystallizable
salts.
Piperine is a very feeble base, being almost insoluble in the
dilute mineral acids, and not cunibiuing with them, but forms
well crystallizable double salts with the chlorides of platinom,
mercury, and cadmium.
PLUMBI ACBTAB.
PLUMBUM ACETICUM.
AeetaU of Ltod. iSug<ir of Lead, PlvmhU Atrlalt,
EPb(C,H,0,),+3H,0; 378.5.
Colorless, transparent, brilliant, monoclinic prisms or plates
(Fig. 142), or, as generally met with, heavy, compact crystalline
masses, somewhat resembling loaf-sugnr,
Fi». 148. having an acetous odor and a sweet, aa-
^^^^^^^^^_ tringent, afterwards metallic taste; they
^SH^^^^^^ contain three molecules ^14.21 percent')
^F^^^^^^B^^H of water of crystallization, and effloresce
K ~3^^B slowly and absorb carbonic acid when
■ ^^^1 exposed to the air; they become black
^^^^^^^^^^^B when in contact with gaseous or dissolved
"■■■■^^^ hydrogen sulphide. When heated to 40*
(T
ac<
C. (104" F.) plumbic acetate loses its
ater of crystallization quickly andcompletelv; it melts at 76* C.
(167° F.)in its water of crystallization, with tlie loss of water and
acetic acid, and is furlh< r decomposed at a higher tcmperatare,
PLUMBUM. 453
leaving a black residue, which is reduced, at a red heat, to plum-
bic oxide or to metallic lead.
Plumbic acetate is soluble in 1.8 parts of water and 8 parts of
alcohol at 15® C. (59^ F.), in 0.5 part of boiling water and 1 part
of boiling alcohol, but insoluble in ether and in chloroform ; its
solution in water has generally a slightly turbid appearance from
traces of plumbic carbonate, which, however, disappears upon the
addition of acetic acid; the aqueous solution has a feeble acid
reaction, forms white precipitates with the alkaline hydrates
(soluble in excess of potassium and sodium hydrates), with the
alkaline carbonates, and with sulphates and chlorides, a yellow
one with iodides, and a black one with hydrogen sulohide and
with sulphides. When completely precipitated by soaium chlo-
ride, the colorless filtrate will assume a deep-red tint with a few
droi)s of solution of ferric chloride.
Maminatton :
Salts of the Alkalies^ Alkaline- Earths, and Ztnc. — An aqueous
solution of the salt is acidulated with hydrochloric acid, filtered,
and the lead completely precipitated by saturation with hydrogen
sulphide. The filtrate, on evaporation, should leave no residue.
If a residue is obtained, it may be dissolved in water, and a por-
tion of the solution tested with sodium carbonate, when a white
precipitate will indicate the presence of salts of bariinn, calcium,
mayiiesium, or zinc, which may be distinguished by the appro-
priate tests; if the dissolved residue gives no precipitate with
sodium carbonate, potassium or sodium salts will be indicated.
Copper may be detected by precij)ilating a solution of the salt
with dilute sulphuric acid, and testing the filtrate with potassium
ferrocyanide, or, by subsequent supersaturation with ammonia-
water, a reddish-brown precipitate in the first instance, and a
blue coloration of the liquid in the latter, will reveal the presence
of copper.
PLUMBI CARBONAS.
PLUMBI SUBCARBONAS. PLUMBUM CARBONICUM. CERUSSA.
Carbonate or Subcarbonate of Lead. White Leid. Basic Plumbic Carbonate,
Ger. Basisch kohlensaurcs Bleioxyd, Bleiweiss ; Fr. Carbonate de plomb ;
Sp. Carbonato de plomo.
(PbCOj), + Pb(OII), ; 773.5.
A heavy, white, opaque, and perfectly amorphous powder, or
friable lumps, which are blackened by hydrogen sulphide. Heated
upon charcoal before the blow-pipe, plumbic carbonate becomes
vellow, fuses, and is finally reducecl to soft, malleable metallic glo-
bules. It is insoluble in pure water, but somewhat soluble in
454 MANUAL OF CHEMICAL AXALTSI8.
water containing much carbonic acid or alkaline bicarbonates ; it
18 wholly d'\^5io\y*^], with effervescence, by diluted acetic and
nitric acids, affording colorless solutions, of a sweet, astringent
taste ; these sr/iutions yield white precipitates with dilute sul-
phuric and hydrfxihloric acids, and with soluble sulphates and
chlorides; they a!?o give a wliite precipitate with solutions of
potajisiurn or soflium hydrate, soluble in an excess of the precipi-
tant, a yellow one with potassium iodide, and a black one with
hydrogen sulphide.
" Examination :
Admixtures of f/arlum^ calcium^ and plumhic sulphates^ remain
behind, upon solution of the white lead in dilute nitric acid.
Their quantity may be ascertained by dissolving 100 parts of the
sample in a sufficient quantity of warm diluted nitric acid, and
collecting and washing the insoluble residue u])on a tared filter;
when completely dry, the weight indicates the percentage of such
admixtures.
If the nature of the admixture has to be ascertained, the residue
is intimately mixed with about three times its weight of anhv-
drous sfxliurn carU^nate, and strongly heated in a porcelain cru-
cible. After Vxjing allowed to cool, the fused mass is lixiviated
with water, filtered, and the filtrate supersaturated with nitric
acid and tested with barium chloride, when a white precipitate
will reveal the presence of sulphate. The residue, upon the filter,
may tluMi be dissolved in acetic acid, and tested with hydrogen
suipiiide for b^ad^ when, after filtration, if necessary, the filtrate
may be tested with potassium chromate for barium, and with
ammonium oxalate for rnlcinm.
Admixtures of adcunn rarljonnfe or jfhosphate, harhan carlo-
tiatr\ and oxide of ^luc^ are also soluble in nitric acid. In order to
delect and to distinguish them, the nitric-acid solution of the
sample is freely diluted with water, and is subsequently saturated
and completely preeipitated with hydrogen sulphide; it is then
filtered, and warmed, to expel the excess of gas, and a small por-
tion of the solution is supersaturated with sodium carbonate; an
ensiling white [)recipitate will confirm the presence of the above
admixtures; in order to ascertain their nature, the remainder of
the solution is nearly neutralized with a few drops of solution of
potassium hydrate and then teste<l, in separate ])ortions, with solu-
tion of calcium sulphate for barium, with oxalic acid, after the
previous addition of a little sodium acetate, for calcium, and by
the addition lirst of sodium acetate and subsequently of ammo-
nium sul]>hide for ziuc.
PLUMBUM. 455
PLIJMBI lODIDIJM.
PLUMBUM lODATUM.
Iodide of Lead, Plumbic Iodide.
Ger. Jodblei ; Fr. lodurc dc plomb ; Sp. loduro de plomo.
Pbl,; 459.7.
A bright-yellow, heavy, inodorous powder, when obtained by
precipitation ; or shining, golden-yellow, six-sided laminae or prisms
of the hexagonal system, when allowed to slowly crystallize from
its solutions. Its specific gravity is 6.1. When heated in a dry
test-tube, plumbic iodide becomes red, and fuses to a thick reddish-
brown liquid, which congeals, on cooling, to a yellow crystalline
mass; at a stronger heat, it is decomposed, with the evolution of
violet vapors ; and, when heated with exsiccated sodium carbo-
nate, on charcoal, before the blow-pipe, it is entirely reduced to
metallic globules.
Plumbic iodide is soluble in 2270 parts of water at 14° C. (57.2°
F.), in 294 parts of boiling water, and also, to a slight extent, in
alcohol; a hot saturated aqueous solution, on cooling, deposits
the salt in brilliant yellow scales; it is readily soluble in acetic
acid, in solution of potassium or sodium hydrate, in concen-
trated solutions of the alkaline or earthy iodides, in a warm solu-
tion of ammonium chloride, and in solution of sodium hyposul-
phite (thiosulphate), from all of which solutions hydrogen sulphide
precipitates black plumbic sulphide.
When shaken with chlorine- water, plumbic iodide suffers par-
tial decomposition, and yields a filtrate from which chloroform or
carbon bisulphide will extract iodine, with a red color. When
boiled with solutions of alkaline carbonates, it is decomposed,
with the formation of an alkaline iodide and plumbic carbonate.
When boiled with granular or powdered zinc and water, less
readily with iron, plumbic iodide is likewise decomposed, form-
ing soluble zinc or ferrous iodide and metallic lead.
Examination :
Phunbic chromate^ which, in its piiysical characters, bears some
resemblance to plumbic iodide, may readily be distinguished from
the latter by triturating 1 part of the salt with 2 parts of ammo-
nium chloride, in a porcelain mortar, and subsequently adding 2
parts of water, when a complete and colorless solution should be
formed. If the solution be afterwards diluted with water, and
the lead completely precipitated by hydrogen sulphide, the fil-
trate, on evaporation to dryness and subsequent ignition, should
leave no residue, thus confirming the absence of other fixed impu-
rities.
AL OP CHEMICA
PLUUBI HITRAa.
PLUMBUM SITRICUM.
mirtilt of Lead. Plumbie NitraU.
Ger. S al pel pran ores Bleio»T<l ; F'- Azotale ile plomb ; 8p. Niirato de plomo.
PKNOJ,; 3305.
Colorless, transparent or opaque, anhydrous, octahedral crysi-
tals, permanent in the air. Heated in a dry test-tube, the crvs-
taU decrepitate, emit yellow nitrous vapors, and leave a resicfue
of plumbic moTioxide. When throwa on red-hot charcoal, the salt
detonales with brilliant sparks, aud deflagrates when triturated
with sulphur.
Plumbic nitrate is soluble in 2 parts of water at IS*" C. (oi*** F.l
and in 0.8 part of boiling water : it is almost insoluble ia alcohol,
lis aqueous solutioD has a sweet, astringent, afterwards metallic
taste, and an acid reaction; it given a while precipitate with sul-
phuric or hydrochloric acid, and with soluiions of Eulpbaies or
chlorides, a yellow one with potassium ictdide, and a black one
with hydrogen sulphide. When triturated with concentrated sul- .
phuric acid, and heated, the salt evolves red nitrous fumes.
Examinatloii :
Salts of the AfkuUts and AlkftHjie Earths. — An aqueous soliitioD
of the salt is acidulated with hydrochloric acid, iiltered, and Uie
lead cfjmpletely precipitated by saturation with hydrogen sulphide.
The filtrate, on evaporation, should leave no residue. If a rcsidne
is obtained, it may be dissolved in water, and a portion of the
solution tested with sodium carbonate ; an ensuing white precipi-
tate would indicate the presence of barium, which may be con-
firmed by other lests. If the dissolved residue gives no precipi-
tate with sodium carbonate, the presence of polaasimn or Bodium
salts will be indicated.
Cojjper may be detected, in the aqneons solution of the salt, by
completely precipitating it with dilute sulphuric acid, and testing
the filtrate with potassium ferrocyanide, or, by subsequent saper-
saluration with ammonia- water; a reddish-brown precipitate in
the first inslnnce, and a blue coloration of the liquid in the latter,
will reveal the presence of copper.
This hook is theproi*'..
COOPER MEDICAL CO:.L..^ ,.
8AN FnA!«JISCO. CAL.
find ia not f'. !>>f r---u--'i ''-«( l-.^
Libm.-ii I:l- . ■ ..<•
Wtlr-r rt. V •
PLUMBUM. 457
PLT7MBI OXIDUM.
PLUMBUM OXYDA.TUM FUSCUM. LITHA.UGYRUM.
Oxide of Lead, Litharge, Plumbic Monoxide,
Ger. Bleiozyd, Bleiglatto ; Fr. Litharge ; Sp. Litargirio.
PbO; 222.5.
A heavy, yellowish or reddish -yellow powder, or small, shining,
rhombic scales of the same color, devoid of odor and taste. Its
specific gravity is 9.36. It fuses at a red heat, assuming thereby
a brownish-red tint, and solidifies on cooling to a crystalline mass;
when heated on charcoal, before the blow-pipe, it is reduced to
the metallic state.
Plumbic monoxide is but sparingly soluble in water, imparting
thereto a feeble alkaline reaction ; it is soluble in warm solutions
of the fixed alkaline hydrates, and in diluted nitric and acetic
acids, without effervescence or residue ; it slowly absorbs carbonic
acid from the atmosphere, and contains the more carbonate the
longer it has been exposed to the air; from this cause, when very
old, it becomes more or less effervescent with acids. The nitric-
acid solution of plumbic monoxide yields white precipitates with
dilute sulphuric and hydrochloric acids, with solutions of sul-
phates and chlorides, and with the alkaline hydrates, which latter,
ammonia-water excepted, re-dissolve the precipitate, when added
in excess; it gives a black precipitate with hydrogen sulphide,
and, when neutral, a yellow one with potassium iodide.
Examhiation :
Phuiibic carbonate and red oxide are detected, when a small
quantity of the litharge is triturated with a little water, and the
mixture is added, drop by drop, to concentrated nitric acid, in a
test-tube; carbonate is recognized by effervescence; red oxide by
a brown residue, insoluble in an excess of acid, with gentle warm-
ing, but soluble upon the addition of a little oxalic acid or sugar;
if this residue, however, does not dissolve, an adulteration with
powdered silicates, crude ferric oxide, etc., is indicated.
Silicates are also indicated by a white turbidity or a flocculent
precipitate, occurring in the solution after the addition of the
oxalic acid, in the preceding test.
Zinc oxide and alkaline earths may be detected by saturating
the dilute nitric acid solution with hydrogen sulphide, so as to
completely precipitate the lead, and filtering; the filtrate, on
evaporation, should leave no residue. If a residue is obtained, it
may be dissolved in a little water, and a portion of the solution
tested with sodium carbonate ; an ensuing white precipitate would
indicate zinc, barium, or. oalciam oxides. In order to distinguish
these, the remainder of :the solvition is tested, in separate portions,
with ammonium sulphide for zinc^ with solution of calcium sul-
pliate for l>ariuvi, and with ainmonium oxalate for calcium; am
ensuing white precipitate in either instance will indicate the r&-
sjwctive impurities.
Copper may be detected by a Wue coloration of the liquid,
when the dilute nitric acid solution of the oxide is precipitated by
ijulphuric acid, and tiubsequently supersaturated with ammonia-
water.
MetaUlc had may be detected by its remaining undissolved
when the oxide is boiled for a short time with acetic acid, or
when digested with a warm solution of plumbic acetate or poUs-
sium hydrate. It may likewise be detected by digesting a small
portion of the litharge with a solution of plumbic nitrate, at a
gentle heat, and with occasional agitation, for about half an hour;
a few drops of the decanted liquid are then diluted with a
Httle water, a little mucilage of starch, and a few drops of dilute
sulphuric ao d and solution of potassium iodide added. If the
Aample con'^ins even traces of metallic lead, this gives rise to the
formation of plumbic nitrite, which will decompose the potassium
iodide, with tlie liberation of iodine, and at once produce a blue
color witli the starch.
FLT7MBI OXIDUM RUBRnM.
PLUMBUM OXVDATUM RUBRUM. MINIUM.
Red Oiidr of L"id. .V;nh.m. TripU.'
ride. Plumbic PluatbaU.
Pbp.; 683.0.
A heavy, orange-red, crystalline powder, which becomes dark
when heated, but regains its original color on cooling; at a rod
heat it loses oxygen and is converted into the monoxide. Heated
upon charcoal, before the blow-pipe, it fuses, and is reduced to
metallic globules. Its specific gravity varies from 9.6 to 9.1.
Red oxide of lead is almost completely soluble in twenty times
its weight of warm glacial acetic acid, forming a colorless oolg-
tion, which is not precipitated by the addition of a mixture of
ether and alcohol ; when treated with warm dilute nitric or aoelic
acid it only partially dissolves, leaving a brown residue of per-
oxide, which is soluble, however, upon the addition of a little
oxalic acid or sugar. A slight remaining turbidity, of a wbttish
appearance, is due to silicic acid, with which red oxide of lead is
generally more or le-is contaminated : any insoluble red or.brown
residue, however, would indicate impurities.
POTASSIUM. 459
The impurities and admixtures which red oxide of lead is liable
to contain, and the methods of detecting them, are the same as
mentioned and described under litharge, on pages 457-458.
POTA88A SXTLPHURATA.
POTASSII SULPHURETUM. POTASSII SULPHIDUM. POTASSIUM
8EU KALIUM SULFURATUM. HEPAR 8ULFURIS.
Sulphurated Potasta. Salphuret of Potassium, Potassium Sulphide.
Ger. ScUwefelleber ; Fr. Sulfure de potasse ; Sp. SAlfuro de potasio.
Solid, fused fragments, of a yellowish-brown color, when freshly
prepared or recently broken ; on exposure to the air they assume
a greenish appearance, and finally become of a dirty white, in
consequence of gradual decomposition by the action of atmos-
pheric moisture and oxygen, the sulphides being successively
converted, with the evolution of hydrogen sulphide, into hypo-
sulphite (thiosulphate), sulphite, and ultimately sulphate. When
moistened with acids, sulphurated potassa evolves hydrogen sul-
phide.
Sulphurated potassa, which is usually a variable mixture of
higher potassium sulphides with hyposulphite (thiosulphate), sul-
phite, and sulphate, and with undecomposed carbonate, is soluble
in about 2 parts of water at 15° C. (59° F.), and is also soluble in
alcohol, leaving behind in the latter case the oxygen salts; these
solutions have an orange-yellow color, a nauseous, alkaline, bitter
taste, and the odor of hydrogen sulphide, which is abundantly
evolved, with the separation of sulphur, upon the addition of
acids; they precipitate metallic sulphides from the solutions of
most of the metallic salts. If a solution of 1 part of the salt in
20 parts of water be boiled with an excess of acetic acid until
hydrogen sulphide ceases to be evolved, the solution filtered, and
to the cold filtrate an excess of tartaric acid added, a white, crys-
talline precipitate will be produced.
The value of sulphurated potassa, when free from an undue
proportion of carbonate, may be approximately estimated by the
amount of crystallized cupric sulphate which is required to
decompose it :
CuS0,.5H,0 + KjSj =. CuS -f S, -f K,SO, + oUfi.
In consideration of the amount of admissible foreign salts, the
preparation should respond to the following test : 10 grams of the
sulphurated potassa are triturated with 12.69 grams of crystallized
cupric sulphate and 60 grams of water, and subsequently filtered;
NtlAL OF CHEMICAL ANALYSES.
l.Iie flllrat« should be colorleai, and aft'ord no coloration or tur-
liidity upon saturation with hvdrogen sulphide (indicating the
presence of at least 56 per cent, of true potassium sulphido).
FOTASBU ACBTAB.
POTASSIUM SEU ICALIUM ACETICOM.
Arnlftle of Polaatiiim. Pohtiiium AettaU.
Qer. EfisigsnurcB Knilum ; Fr. Acutule du pntKue ; Sp. AceluLo dv polnsa.
KC,H,0,; 98.
A Rnow-white, very deliquescent salt, of a foliaceoua or fibrous
satiny appearance, or a white granular powder, unctuous to the
loucti, and of a warm, pungent, saline taste, and poBSessing a nea-
tral or faintly alkaliue reaction ; it fuses at 292° C. (557,6^ K.)
without change, solidifying upon cooling to a crystalliue nisas,
but is decomposed at a higher temperature with the evolution of
empyreumatic, inl^atnmable vapors, leaving behind a mixture of
caroon and potassium carbonate.
Potassium acetate is soluble in 0.4 part of water, in 2.5 parts of
alcohol, and in 3 parts of glycerin at 15° C. (59* F,); its dilute
aqueous solution assumes a deep red color with one or two drops
of solution of ferric chloride, and yields a white granular precipi-
tate with a concentrated solution of sodium bitartraie or of tar-
taric acid. Potassium acetate disengages tbe vapor of acetic acid
with concentrated sulphuric acid, and the vapor of acetic ether
when heated with a mixture coasisting of equal parts of alcohol
and sulphuric acid.
ExamlnatloD :
Mflaia are detected in the aqueous solution, previously acida-
lated with hydrocliloric acid, by a dark coloration or precipitate
with hydrogen sulphide, or, after neutralinalion with ammonia-
water, \ij the addition of ammonium sulphide; if a preoi(>itat« is
produced by these reagents, a portiou of the acidulated solution
of tbe salt may then be tested with potassium ferrocyauide; cop-
per will be indicated by a reddish-brown coloration, iron by a
blue one,
Tarlralfs, sulphates, and chlorides are iudicated by the occur-
rence of a turbidity wlieu a conceutraled aqueous solution of the
salt is dropj)ed into strong or absolute alcohol ; the latter two are
also recognined in the diluted solution, acidulated with nitrio
acid, by while precipitates when tested in separate portions with
argentic nitrate and barium nitrate respectively.
Carbonatea, silica, oxiA., alkaliue earths may be detected by din-
solving a portiou of the. ^alt iu ,water acidulated with hydrociilorio
POTASSIUM. 461
acid ; effervescence will indicate carbonates ; upon evaporating
the resulting solution to dryness, and treating the residue with
water, the silica will remain undissolved ; and the solution, after
filtration, and the addition of sodium carbonate in slight excess,
will yield a white precipitate, if alkaline earths be present.
Organic impurities will be indicated by a dark coloration when
a little of the salt is strewn upon colorless concentrated sulphuric
acid.
Estimation :
About 5 grams of the salt are accurately weighed, and ignited,
at a strong heat, in a porcelain crucible, until inflammable vapors
cease to be evolved ; the residue is then dissolved in water, and
the solution, contained in a beaker, after the addition of a few
drops of a solution of litmus, is titrated with a standard solution
of oxalic or sulphuric acid (page 82) until, with the application
of a gentle heat to effect the complete removal ot the disengaged
carbonic acid gas, a slight excess of acid has been employed, and
the liquid assumes a bright cherry-red color. The excess of acid
is then inversely titrated with a standard solution of potassium or
sodium hydrate (page 87) until a decided blue coloration of the
liquid is just produced, when the number of cubic centimeters of
alkali solution, subtracted from that of the acid first eniployed,
will give the amount of the latter required for the exact neu-
tralization of the salt. One cubic centimeter of the normal acid
solution corresponding to 0.069 gram of potassium carbonate, or,
as its equivalent, 0.098 gram of potassium acetate, the latter deci-
mal, multiplied by the number of cubic centimeters of the normal
acid solution employed for neutralization, will represent the
amount of pure potassium acetate in the quantity under esti-
mation.
By the employment of 4.9 grams of potassium acetate, and a
strictly normal solution of oxalic or sulphuric acid, the number
of cubic centimeters of acid required for the exact neutralization
of the salt, after the above treatment, when multiplied by 2, will
represent without further calculation the percentage purity of
the salt under examination.
The United States Pharmacopoeia requires that if 4.9 grams of
potassium acetate are ignited until gases cease to be evolved, the
alkaline residue should require, for complete neutralization, not
less than 49 cubic centimeters of the volumetric solution of oxalic
acid (corresponding to at least 98 per cent, of absolute potassium
acetate).
This hook is the p'Oi >
COOPER MEDICAL CO:
8AN FRANCISCO. OAU
and is not to he r^'o^ • d /' ^r.i / ^
II ' t' f ' t
.iJk4» K.
MANUAL OF CI! EMU
ANALYSIfj.
POTA8SII BICARBONAS.
POTASSIVM SEU KALIUM BICABHONICUM
Sicarbi/naU of PoUit
KHCO,; 100.
Transparent, colorless, priamatic crystals, belonging to the mono-
clinic syetetn, and having the specific gravity 2.153 ; they are pcr-
nianent in dry air, odorless, of a saline and slightly alkaline taste,
and a feebly alkaline reaction; when exposed to a red heat, they
lose, in consequence of the elimination of water and carbonic acid
gas, SI |ier cent, of their weight, and are convened intn the normal
or neutral carbonate : 2KHC0, m> K^CO. + H,0 + CO,.
Potassium bicarbonate is soluble in 3.2 parts of water at lo-" C.
(59° r.), forming a slightly alkaline solution which effervesces
with acids and evolves carbonic acid gas when heated to boiling;
it gives a white granular precipitate with excess of tartaric acid,
but no precipitate with magnesium sulphate unless when healed.
It is almost insoluble in alcohol.
Ex&miaatlon :
Normal /io!assium or sodium carlonoles will be indicated by a
strongly alkaline reaction of the salt to test-paper, and may be
detected in the cold aqueous solution by testing it, in separate
portions, with a solution of magnesium sulphate and with mercuric
chloride; a white precipitate with the first-named reagent, solu-
ble u[iou ihe addition of ammonium chloride, and a brick-red one
with the second, would indicate neutral carbonate. They may also
be detected by carefully mi.xing, without agitation, equal volumes
of a solution of 1 pan of potassium bicarbonate in 200 i>»rt8 of
water with a solution of 1.22 parts of crystallized barium chloride
in 200 parts of water; the immediate formation of a while pre-
cipitate will likewise reveal the presence of neutral carbonate.
Other Imiiurities. — The aqueous solution is slightly suiiersatu-
rated with diluted nitric acid, evaporated to dryness, and tne dried
mass re-dissolved in water; a white insoluble residue would indi-
cate sUicates; the solution, if necessary, is filtered, and tested in
separate portions with argentic nitrate for chloride, and with
barium nitrate for sulphate; a white turbidity with argentic
nitrate, gradually turning dark, would indicate potassium hypo-
sulphite (thiosulphate) ; in this case, as a confirmatory teat, *
small portion of the potassium bicarbonate may be dissolved in
about five times its weight of water, the solution slightly supersatu-
rated with acetic acid, and then a few drops of mucilage of starch,
and subsequently of solution of iodinizcd potassium iodide are
added, drop by drop ; ' "
; the first drops of the latter reagent should
POTASSIUM. 463
at once produce the blue coloration which will not take place
immediately if potassium hyposulphite be present in the salt.
Nitrates may be detected by dissolving a portion of the salt in
cold concentrated sulphuric acid, and, after effervescence has
ceased, carefully adding to the solution a concentrated solution
of ferrous sulphate, so as to form two layers (Fig. 143); a dark
Fio. 143.
coloration at the surface of contact of the two liquids will reveal
the presence of nitrates.
Metals are detected by saturating a solution of the salt, pre-
viously acidulated with hydrochloric acid, with hydrogen sul-
phide, and, after the separation of any precipitate which may be
thus formed, by the subsequent addition of ammonia- water and
ammonium sulphide; a dark coloration or precipitate in either
instance would indicate the presence of metallic impurities, which
may be further examined as to their character by the methods of
systematic analysis, as described on pages 51 to 61.
Estimaticm:
One hundred parts of potassium bicarbonate require for exact
neutralization 70 parts of citric, or 75 parts of tartaric, acid.
The quantitative estimation of the salt may, however, be more
conveniently accomplished volumetrically, by dissolving 5 grams
of the salt in a small quantity of water, and titrating the solution,
♦contained in a beaker, after the addition of a few drops of litmus
solution, with a standard solution of oxalic or sulphuric acid (page
82). The liquid, during the addition of the acid, should be gently
warmed, in order to completely expel the disengaged carbonic
acid gas, and a slight excess of acid employed, which will be evi-
dent by the bright cherry-red tint of the liquid ; the excess of
4f>4 MANUAL OF CHEMICAL ANALYSIS.
ncid being subsequently inversely titrated by tneaiifl of a standard
ftlkali solution (page 87). The number ol" cubic centioieler^ of
normal acid which are thus required for the exact nenlraliziitinn
of 5 grams of the salt, when multiplied by 2, will represent the
percentage purity of the salt under examination : One cubic oeuti-
meter of the normal acid corresponding to 0,1 gram of pure crys-
tallized potassii^m bicarbonate.
FOTABSn BICHROHAS.
POTASSIUM 8EU KALIUM HICHIiOMICl'M. KALIUM
CHROMICLM liUBItUM.
Biehromatt of Fodtaaium. Polauium BichramaU.
Ger. Doppelt cUromsRiirpB Eallum ; Fr. BIctiroDiale de pnUsse ;
Sp. Bici'omalo lie potasa.
KjCrp,; 294.S.
Large, transparent, ornnge-red, prismatic, or tabular crystals,
belonging to the triclinic systeiii-(Fig, 144), and having the spe-
cific gravity 2.692 at i° G. (39.2*^ F.). They
Fio. 144. are anhydrous, and permanent in the air; ex-
0po.sed to heat, they fuse below redness, forming
a dark-brown liquid, which solidifies on cooling
to a crystalline mass, and are decomposed at a
red heat with the evolution of oxygen, leaving
a residue consisting of green chromic oxide
find yellow potassium chromate, which may be
separated by the ready solubility of the latter
in water.
Potassium bichromate is soluble in 10 parts
of water at 15* C. (59" ¥.), and in 1.5 parts of
boiling water, yielding an intensely ornnge-
yellow solution, with n cooling, bitter, metallic
taste, and an acid reaction ; it ia insoluble in alcohol. The aque-
ous solution becomes lemon-yellow with the alkaline hydrates and
carbonates, and green or almost colorless, with the formation ofa
brown precipitate, when heated with reducing agents: it forms
insoluble, colored bichromates and chromates with the solutions
of most metallic salts. AVhen the powdered salt is heated with
hydrochloric acid, vapors of chlorine are evolved, and whei^
heated with concentrated hydrochloric or sulphuric acid and a
little alcohol, a vehement reduction takes place, and the liquid
acquires a deep green color, A conceutrated solution of the salt
gives a white, granular precipitate with a concentrated solution
of sodium bitartrate.
POTASSIUM. 465
Examination :
Sulphate may be detected hy heating to boiling a mixture of
the aqueous solution with an equal volume of concentrated hydro-
chloric acid and a few drops of alcohol ; when subsequently diluted
with water and tested with barium chloride, a white precipitate
will ensue if sulf)hate be present.
Chloride may be detected when the aqueous solution of the salt
is mixed with about one-third of its volume of concentrated sul
phuric acid, and when afterward a little alcohol is added; the
mixture will become green, with spontaneous ebullition ; it is
then heated, and subsequently diluted with water, and tested
with argentic nitrate for chloride.
POTASSII BITARTRAS.
POTASSIUM SEU KALIUM BITARTAIUCUM. TARTARUS
DEPURATUS. CREMOR TARTARI.
Bitartrnte of Potannium. Cream of Tartar. Potassium Bitartrate.
Ger. Saiires wcinsaures Kalium, Weinstcin ; Fr. Tartrate acide de potasse;
Sp. Bitartrato de potasa
TCTirho _ cii(on)-co-OK
Cn(OII)-CO-OH» ^^^•
White, semi-transparent, hard, prismatic crystals, belonging to
the rhombic system, or aggregated groups of crystals, or a white,
somewhjit gritty powder, permanent in the air, and having a spec,
grav. of 1.957, a sour taste, and an acid reaction. When exposed
to heat, in a porcelain crucible, potassium bitartrate is decom-
1)osed, with the evolution of cmpyreumatic, inflammable vapors,
eaving a black residue of carbon and pure potassium carbonate ;
this residue, when dissolved in a little water, gives a filtrate which
effervesces with acids, and forms a white, granular precipitate
with an excess of tartaric acid.
Potassium bitartrate is soluble in 210 parts of water at 15° C.
(59° F.), and in 15 parts of boiling water, but is WQry sparingly
soluble in alcohol, and insoluble in absolute alcohol and ether; it
dissolves wholly and readily in mineral acids, as also in solu-
tions of citric and oxalic acids, in dilute solutions of the alkaline
hydrates and carbonates, of boracic acid, and of sodium biborate.
If the aqueous solution of the sait be exactly neutralized with a
solution of potassium hydrate, and a few arops of solution of
argentic nitrate added, a white precipitate is produced, which
becomes black on boiling.
30
4titj MANUAL OF CHEMICAL AJiALYST
ExaminatioQ :
/jiMohihle admixtvTfg (sucli ns terra alia or white clay. Bnd
similar crude adulterants) are indicated by a residue left when
small samples of the powuer are dissolved separately in a warm,
diluted soluliuD of potassium hydrate, and in dilute hydrocliioric
Hcid.
•^ufphalts and chhriiifs are detected by agitating a small por-
tion of the salt with about ten times its weight of warm water,
and by testing porlions of the clear liquid, when cool, and after
the addition of a few drops of nitric acid, with barium nitrate for
sulphates, and with argentic nitrate for chlorides.
Alum. — An adulteration of powdered cream of tartar with
alum is at once indicated by a grt^atcr solubility of the salt in
water, by its intumescence upon incineration, and by the incom-
plete solubility of the fused residue in water, as also by the odor
of ammonia, and the production of while fumes from a glass rod,
moistened with acetic acid, when the powder is heated willi a
solution of potassinm hydrate, and by ilie formation of a white
precipitate, when a few drops of this alkaline solution are allowed
to fall into a dilute solution of ammonium chloride.
Mftallic impuriiiet may be detected in the solution of the salt
in ammonia-water, by a dark coloration or precipitate upon the
addition of ammonium sulphide.
Calcium salts may be best detected when 1 gram of the salt is
repeatedly agitated with 5 grams of acetic acid, at the ordinary
temperature, during half an hour, the solution suVisequeutly di-
luted with 25 grams of water, filtered, and S drops of solution of
ammonium oxalate are added ; a while turbidity, occurring either
iit once or within half a minute, will indicate the presence of
more than 0.3 per cent, of such impurities.
EBtfmatioii :
The quantitative estimation of potassium bitartrate may readily
be accomplished by its conversion into carbonate, and the estima-
tion of the latter by means of a normal acid.
4.70 grams of the salt are ignited in a porcelain crucible, at a
red heat, until gases cease to be evolved, and the residue subse-
quently dissolved in water, and filtered; the solution, together
with the washings from the filter, contained in a beaker, after the
addition of a few drops of litmus solution, is then titrated with a
standard solution of oxalic or sulphuric acid (page 82) until, with
the application of a gentle heat to expel the disengaged carbonic
acid gas, a slight excess of acid has been employed, and the liquid
assumes a bright clierry-red tint; the excess of acid is then in-
versely titrated with a standard solution of potassium or sodium
hydrate (page 87) until the liquid just assumes a permanent blue
oolor. If the salt be perfectly pure, 25 cubic centimeters of the
normal acid solution will be required for the exact neutraliza*
tion of the quantity indicated, or, the percentage purity of the
POTASSIUM. 467
salt will be determined, when, for the neutralization of the above
stated amount, the number of cubic centimeters of normal acid
employed are multiplied by 4 ; one cubic centimeter of the nor-
mal acid solution corresponding to 0.069 gram of potassium car-
bonate, or, as its equivalent, 0.188 gram of potassium bitartrate.
POTASSII BROMIDUM.
POTASSIUM SEU KALIUM BROMATUM.
Bromide of Potassium. Potassium Bromide.
Ger. Bromkalium ; Fr. Brdmure de potassium ; Sp. Bromuro de potasio.
KBr; 118.8.
Anhydrous, colorless, semi-transparent, cubical crystals, some-
times elongated into prisma, or flattened to plates, permanent in
the air, and of a spec. grav. of 2.69 at 4° C. (89.2^ F.); when ex-
posed to heat, they decrepitate, and fuse at a little below a red
heat, without decomposition. When a few grains are triturated
and subsequently heated, in a dry tube, with a little potassium
bisulphate, yellowish-red vapors of bromine are evolved.
Potassium bromide is soluble in 1.6 parts of water and in 200
parts of alcohol at 15^ C. (o9° F.), in 1 part of boiling water, and
in 16 parts of boiling alcohol ; its aqueous solution has a strong
saline taste, is neutral in its action upon litmus, and, when dropped
into a very dilute solution of argentic nitrate, causes a yellowish-
white, curdy precipitate, which is insoluble in dilute nitric acid,
but soluble in a large excess of ammonia-water (distinction, in the
latter instance, from argentic iodide); when dropped into a very
dilute solution of mercuric chloride, no reaction takes place (addi-
tional distinction from potassium iodide): it gives a white, granu-
lar precipitate with a saturated solution of sodium bitartrate.
Potassium bromide and its solution' may also be distinguished
from the iodide by adding to the solution a little mucilage of
starch, and subsequently a few drops of chlorine- water ; the solu-
tion of the bromide becomes light yellow ; that of the iodide will
at once assume a deep- blue color.
Examination :
Moisture which may be contained in the crystals, as well as in
the granular form of the salt, is recognized, and may be deter-
mined, by the loss of weight when the salt is dried at 100° C.
(212° F.).
Potassium carbonate is detected by a white turbidity occurring
upon the addition of a little of the concentrated solution of the
salt to lime-water, as also by a decided alkaline reaction, when a
few fragments of the salt are placed upon moistened red litmus-
paper.
■ItiS MANUAL OF CnSUIOAL ANALYSIS.
Sii?ihalfs may be deteoicd, in tbe aqueous 8olatioTi, acidulated
will) A few (lrci}>8 of diluied nitric acid, by a wliiie preoipiuie with
bHriutn nitrate.
Polaimium bromate ia detected by placing a Utile of the pow-
dered salt upon a piece of while porcelain, nnd sHbsequeutljr add-
ing one drop of dilute siilpliurlc acid : a yellow coloration of ihe
moistened surface of the ualt, or the developed odor of bromine,
will reveal the presence of bromate. The presence of tbe latter,
in an aqueous solution of tiie salt, may also be detected by the
liberation of bromine upon the addition of a fow drops of dilutt!
sulphuric acid, imparling a yellow color, which, upon puljsequenl
agitation of the solution with a few drops of carbon bisulphide,
will bo absorbed by the Inller.
Potnasium and sodiutn chloriJex are distinguished from potaf
siuni bromide, and may be recognized by adding a few drops of
chlorine-water to the aqueous solution of the salt; if this ia bro-
mide, the mixture assumes at once a yellow color, which, how-
ever, will be completely abstracted from the aqueous solution by
chloroform, ether, or carbon bisulphide, when agitated therewith.
This reaction does not take place with potassium or sodium
chloride.
If an admixture of potnssium chloride, or other salts, be sus-
pected, the purity of the snitiple may be ascertained by proparing
a solution of 1 gram of Ihe dry, t;rystallJzc(l salt in about 10 times
its weight of water, acidulated with a few drops of diluted nitric
acid, and completely precipitating it with a solution of argentic
nitrate; the precipitate ia collected upon a moist, tared filter, is
washed, dried, and, when completely dry, weighed. If tbe salt
was pure potassium bromide, the obtained argentic bromide
should weigh 1.58 grams; if it contained potassium or sodium
chloride, the weight, [provided the salt is free from olher impuri-
ties, will be greater in proportion to the amount of those admix-
tures, since their molecular weights are lower; 1 gram of jmtvs
slum chloride, for instance, would give 1.92 grams of argentic
chloride.
The same test may also bo used to indicate the purity of the
bromide, by ascertaining the quantity of argentic nitrate required
to precipitate completely a certain weight of potassimn bromide,
1 gram of which requires 1.43 grams of argentic nitrate for pre-
cipitation.
The following additional methods for the detection of an ad-
mixture of chlorides may also be employed, A portion of tbe
salt, dissolved in water, is completely precipitated by argentic
nitrate, the washed and still moist precipitate digested for some
time with a cold. !>aturHted solution of ammonium carbonate, sub-
sequently filtered, and the filtrate supersaturated with nitric acid :
the production of a white, curdy precipitate will reveal the pres-
ence of chloride.
P0TA8BIUH. 469
The presence of much smaller amounts of chloride, and less
than that admitted in the officinal salt, may be detected as fol-
lows: 6 grams of the powdered and well-dried salt, together with
6 grams of pure powdered potassium bichromate, are introduced
into a small flask, and 15 grams of concentrated sulphuric acid
are added. The mixture is then submitted to distillation at a
gentle heat, and the distillate collected in a receiver or flask con-
taining a small quantity of ammonia-water (F,g. Ii5). Bromine
distils over, and is dissolved by the ammonia- water without color;
but, if chlorides are present, clilorochromic anhydride, CrOjCI,, is
produced, distils over, and forma ammonium chromate, which
imparts a yellowish color to the distillate ; by subsequently heat-
ing the latter with a little hydrochloric acid and alcohol, the
bright green color of the chromic salt will be produced.
Nitrates may readily be detected, if the salt be free from bro-
mate, by an ensuing intense yellow coloration, when a solution of
a few fragments of the powdered salt in twenty times their weight
of dilute sulphuric acid is heated to boiling. In the presence of
bromate, nitrates will be indicated by the development of the
*AoT of atftmonia, when the salt-, together with an equal weight of
iron filings, zinc filings, and solid sodium or potassium hydrate, is
gently heated, in a tCMt-tuhc, with an equal volume of water. If,
however, ammonium salts be originally present as an admixture,
the ammonia must first be completely expelled, by heating a por-
tion of the salt with a strong solution of potassium hydrate, after
which, the iron and zinc filings may be added, and the test subse-
quently performed for nitrates, as above described.
Gstimation :
The estimation of potassium bromide, or the amount of chloride
which may be contained therein, is most readily accomplished
470 MANUAL OF CHBMICAL A5ALT8I8.
vol u metrically. Two erams of the p^itassium bromide, previously
reduce«i tn powiler an«l carefully dried, are ilissolveil in water to
the measure of 1«h;i cubic centimeters. 10 cubic centimeters of this
s^jlution. corresponding to 0.2 gram of pMassium bromide, are then
brought into a Ivaker. diluted with al>>iit riO cubic centimeters of
water, and, after the addition of a few drops of a solution of potas-
sium chroinatc. the s^^lution is titrated with a decinormal solution
of argentic nitrate < page OS) until a permanent reddish-brown col-
oration is pro^liiced. If the salt is pure potassium bromide, 16.8
cubic centimeters of tlie silver soluti«^n will be required to pro-
duce this etYect. as containing 0.2S.VJ gram of argentic nitrate,
which corrcsp«»nds to <».2 gram of |>«»tassium bromide, according
to the equation AgXO, : KBr =» 0.2^ot) : 0.2. If the salt was
170 lli^
pure potassium chloride, 2k\.^-^ cubic centimeters of the silver
solution would be re«iuired for its complete precipitation, in ac-
cordance with a similar proportion ; the ditference in the amount
of silver solution, required for 0.2 gram of the two salts, would
there ft)re be 2t).S4 — l^^.^O s 10.04 cubic centimeters ; from which
it follows, that for each O.IOW cubic centimeter silver solution
required in excess of 16.S cubic centimeters in on.lor to effect
complete precipitatii>n, 1 [>cr cent, of potassium chloride will be
reprcstMited, as =« 0.1004. It is evident, tliat the presence
of potassium io<lide, or other alkaline chlorides or bromivles, wc-^uld
intlnenre the result in proportion to the quantityof the admixture.
The United States Pliarmacop<eia directs that if -i grams of the
well-dried salt l)e dissolved in ilistilled water to make 100 cubic
centimeters, and In cubic centimeters of this solution be treated
with a lew dro|>s of test -solution of potassium bichromate, and
then voluinetrie solution of ariientic nitrate l>e added, not more
than 2o.7 ruble centimeters of tlie latter should be consume*!
before tiie reil c«)lor ceases to disappear on stirring (indicating
the absence of more than '6 piT cent, of chloride).
POTAS8II CARBONAS CRUDUS.
POTASSU'M Si:U KALIUM rARBoMCUM CRUDUM.
6V u de Ci I rhu miU uf Ptit'Htm'urn. Pt'frlanh,
G<T. Uohos kohU'iisHurrs K.iliuin, P«>ttasrhe ; Fr. Potasse impure ;
Sp. Potusa onlinaria.
White, bluish-white, or red<lish-whitc masses (the color being
dependent upon the j)resence of small amounts of potassium man-
ganatc or ferric oxide), or a coarse granular powder intermingled
POTASSIUM. 471
with smaller lumps, somewhat deliquescent, and of a burning,
alkaline taste and strong alkaline reaction. Water extracts from
pearlash the potassium carbonate and hydrate, and the soluble
impurities, the greater part of the impurities remaining behind
(sulphates, chlorides, silicates, phosphates, and carbonates of
calcium and aluminium); the filtered solution effervesces with
acids, and yields a white, granular precipitate with an excess of
tartaric acid.
The examination of pearlash consists in the determination of
the quantity of soluble potassium carbonate and hydrate, or the
available potassium oxide.
Approxunate Estimation :
One hundred parts of commercial pearlash, when successively
exhausted with about ten times its weight of warm water, afltbrd
a solution which should neutralize at least 58 parts of sulphuric
acid of 1.843 spec. grav.
Volumetrio Estimation :
The estimation of the amount of pure potassium carbonate in
pearlash, when free from alkaline hydrates and sodium carbonate,
is readily accomplished as follows. 34.5 grams of the pearlash
are dissolved in water to the measure of 500 cubic centimeters.
Of this solution, after the insoluble impurities have subsided and
the liquid has become perfectly clear, 100 cubic centimeters (cor-
responding to 6.9 grams of the pearlash) are brought into a
beaker or small flask, and a few drops of litmus solution are
added. A standard solution of oxalic or sulphuric acid (page 82)
is then allowed to flow into the liquid from a burette, until an ex-
cess of the acid has been employed, and the liquid, after being heated
to boiling, in order to completely expel the liberated carbonic acid
gas, assumes a cherry-red color. The excess of acid is then inversely
titrated with a standard solution of potassium or sodium hydrate
(page 87) until a permanent blue coloration of the liquid is pro-
duced. From the amount of acid required for the exact neutral-
ization of the quantity of pearlash em})loyed, the amount of pure
potassium carbonate may be calculated: o'le cubic centimeter ot
the normal acid solution corresponding to 0.0692 gram of potas-
sium carbonate ; or, the number of cubic centimeters of the acid
solution, if strictly normal, which is required for the neutraliza-
tion of the above amount of the salt, will indicate at once its per-
centage purity ill potassium carbonate.
If the pearlash contains potassium hydrate in addition to po-
ta.ssium carbonate, which will be indicated by an alkaline reaction
of the solution of the salt after its complete precipitation by
barium chloride and subsequent filtration, the hydrate will also
be neutralized by the acid, and the estimation of the amount of
carbonate would therefore be incorrect. In the latter case, the
amount of potassium hydrate and carbonate may be separately
estimated according to the following method : 100 cubic centi-
472
MANUAL OF CUB MIC
meters of the above aoliilion (correspondLng to 6.9 grama of the
pearlaali) are mixetl with an excess of a solution of barium chlo-
ride, and to the iinfiltered solution, containing the deposited
barium carbonate, normal nitric acid is added from a buretie,
until a dro]) of the mixtiiro no longer produces a brown atein
upon turmeric paper. The liumbcr of oubie centimeters of the
acid solution which are required to produce this reaction cor-
responds to the amount of potassium hydrate in the pearlosh: one
cubic centimeter of the normal nitric acid corresponding lo
0,056 gram of potassium hydrate. Tlie entire mixture, after the
acldilion of a few drops of litmus solution, is then titrated, with
the aid of heat, with an excess of normal nitric acid, until a
cherry-red tint of the liquid is produced, and subsequently io-
versely titrated with a normal alkali until the red tint of tho
liquid is just changed to a ponnanent blue. The number of cubic
centimeters of the normal nitric auid which are required in the
last operation, after the deduction of the normal alkali solution
subsequently em ployed, will correspond to the amount of potassium
carbouate present in the salt: one cubit centimeter of normal nitric
acid corresponding to 0.069 gram of pure potassium carbonate.
If sodium carbonate be also present in the pearlash, the re&ults
of the above methods of estimation will be influenced in proportion
to its amount, and their correctness accordingly impaired. The
estimation of the amount of sodium carbonate may also be quite
readily accomplished by the following method: 10 grams of the
pearlash are dissolved in 10 grams of hoi water, the solution fil-
tered, the filter witli its contents of insoluble matter siubaequenlly
washed with 5 grams of water, and the entire filtrate finally
supersaturated with acetiu acid. Tlie Kohition is then evaporated
up<m the water-bath to dryness, and the residue healed with 40
cubic centimeters of alcohol, of the apec. grav, 0,S30, whereby th«
acetates ofpotassium and sodium pass into solution, and the sal-
phates, chlorides, phosphates, and silicates remain undissolved,
To the solution thus obtained, a solution of 21 grams of tartaric
acid in 20 parts of hot water is added until, after standing for
some hours, no further precipitate of potassium bitartrate is pro-
duced. The mixture is then filtered, and the precipitate, con-
tained upon the filter, washed with alcohol, until a few drops of
the filtrate, after active agitation with a little potassium acetate,
remain perfectly clear. The filtrate is subsequently evaporated
to dryness, and gently ignited; a tew drops of water are then
added, and the operation repeated until, upon ignition, the mass
becomes completely incinerated. The ignited mass is then dis-
solved in water, neutralized with hydrochloric acid, and sgaia
evaporated. The sodium chloride thus obtained is dissolved lu t
small amount of water, a little ammonium carbonate added, and
again evaporated to dryness, in order to remove the iron aud
aluminium, aa also traces of calcium and magnesium which laay
POTASSIUM. 473
be present. The dried residue is then extracted with warm
water, and the solution, wh'ch now contains pure sodium chlo-
ride, filtered, evaporated to dryness, ignited in a covered platinum
crucible, and its weight finally determined. From the weight of
the sodium chloride the amount of anhydrous sodium carbonate
may readily be calculated : 100 parts of the former corresponding
to 90.6 parts of the latter.
When the pearlash contains both potassium and sodium car-
bonates, and a determination of the relative amount of each is
required, an estimation of the amount of carbonic acid contained
in a weighed portion (about 2 grams) of the ignited soluble salt
must be made, as described on page 86. From the total amount of
carbonic acid, the amount corresponding to that of the sodium
carbonate present in the salt may be deducted, when the remain-
der will correspond to the percentage of potassium carbonate, and
should conform with the results of the volumetric estimation.
POTASSn CARBONAS DEPURATUS.
P0TA8SIUM SEU KALIUM CARBONICUM DEPURATUM.
Purified Carbonate of Potassium. Purified Pearlash.
Ger. Gereinigtcs kohlensaiires Kalluin ; Fr. Potasse purifiee ;
Sp. Potasa refinada.
2K,CO,.3H,0; 330.
A white, crystalline, or granular powder, permanent in a dry
atmosphere, but deliquescent in a moist one, and possessing a
strongly alkaline taste and reaction ; when heated, on platinum
wire, in the non-luminous flame, it communicates to the latter a
violet color.
Purified pearlash is soluble in 1 part of water at 15^ C. (59° F.),
and in 0.7 part of boiling water, forming a strongly alkaline solu-
tion which frequently appears slightly turbid, and deposits gradu-
ally a flocculent or gelatinous sediment of silicic acid ; it is insolu-
ble in alcohol. Its aqueous solution is decomposed by acids, with
eflfervescence, yields a white, amorphous precipitate with magne-
sium sulphate, and a white, crystalline one with an excess of tar-
taric acid.
Purified pearlash contains about 80 per cent, of potassium car-
bonate, and not more than 15 to 18 per cent, of water, which latter
is lost by exposure to a red heat.
Examination :
Potassium hydrate is indicated in the solution of the salt, by an
alkaline reaction after its complete precipitation with an excess of
barium chloride, and subsequent filtration ; its amount may be
approximately estimated by agitating a few grams of the salt
with absolute alcohol, filtering the solution, and evaporating the
474 MANUAL OF CHKMICAL ANALYSIS.
filtrate, toirether with the alcohoh'c washings therefrom, to com-
plete ilryness, in a tared porcelain capsule; the weight of the
dried resitlue will indicate approximately the proportion of potas-
sium hydrate contained in the s:ilt.
F'trei'jn Suits. — A small portion of the purified potassium car-
b<^nate is dissolved in an equal weiirht of water, in a test-tube;
the solution shouM be complete and limpid, or nearly so; it is
diluted with an equal volume of water, tiltered, and supersatu-
rated with hydrochloric acid ; a gelatinous precipitate after a time
would indicate sUirlc acvl: the liquid is then tiltered, and part of
the filtrate supersaturated with ammonia-water, when a white tur-
bidity would indicate alumina urn salts: the other part of the fil-
trate is tested with barium chloride for stilphate.
Chloride and phosphaV' may be detected in the diluted solution
of the salt, supersaturated with nitric acid, by testing it in two
portions, with argentic nitrate for chloride, and by su[)ersatura-
tion with ammonia-water, and the subsequent addition of test
magnesium mixture, for phosphate.
SuIfJu'fr and hf/posulph'te are detected in the filtered solution
of the salt, slightly superset urate<l with acetic acid, by adding a
few drops of mucilage of starch, and subsequently two or three
drops of diluted solution of it)dinized potassium iodide; the first
drop of the latter solution should prixluce a blue coloration at
once, whirh will not ix^cur before the addition of several drops, if
the above impurities aro contained in the salt.
Sn'Unh} C'lrf'^tn'tt,: may be detected by a white, crystalline pre-
cipitate, ocenrriiiir at once or after some time, when a hot diluted
solution oi the potassium carbonate is nearly neutralized with
acetie acid, and subsequently tested with potassium antimoniaie.
}ft'taJb'f^ {inpnriti»s are <letected in the tiltered .<olution of the
salt, by <livitling it into two parts, one o{ which is su|>er.satu rated
with hvdrocliloric acid: both are then saturated with hvdrocren
sulphide, when any coloration or }>recipitate in either of the
liquids would iuilicate the presence of foreign metals.
Estimation :
Wat^r. — The percentage of water containe<l in the salt may be
determined by its loss of weight, up«)n ignition in a small porce-
lain crucible, at a red heat.
Pnfassitim <\u'hi,n'tft', — About o irrams of the .^^alt, accurately
weigluHl, and previtnisly deprived of water, by ignition at a strong
heat in a small porcelain crucible, are dissolved in abt)ut 20 cubic
centimeters of wat<*r, in a beaker or small tlask, and a few drops
of litmus solution adileil : the solution having been heated to boil-
ing, a standard >oliition o^ oxalic or sulphuric acid (page 82) is
aUowed to tlow into thi' litpiid from a burette until, with the con-
tinuance of th(^ heat to expi4 the liberateil carbonic acid gas, a
slight exci\<s of acid has been employed, and the liijuid a.'tsumes a
bright cherrv-red lint : the excess of aciil is then inversely titrated
POTASSIUM.
475
with a standard solution of potassium or sodium hydrate (page
87), until the red tint of the liquid is just changed to a permanent
blue. From the number of cubic centimeters of acid solution
required for the exact neutralization of the salt, the amount of
pure potassium carbonate contained therein may be calculated :
one cubic centimeter of the normal acid solution corresponding to
0.0692 gram of anhydrous, or 0.0825 gram of crystallized potas-
sium carbonate, 2KjC03.3H,0.
If alkaline hydrates or sodium carbonate be present in the salt,
the above method of estimation must be modified, as described in
the preceding article, on pages 471 to 473.
Table of the amount of dry Potassium Carbonate contained in solutions
of the salt of different specific gravities.
Temperature 150 C. (59^ F.).
Percent.
of K.CO3.
1
2
8
4
5
6
7
8
»
10
11
12
18
Specific
;| Per c<'nt.
of KjCOa.
1.00914 '
1.01820 '
1.02743 '
I.O8O08
1. 04572 I
l.O.lolS !
1.06454 I
1.07391$ '
1.08337
1.09278 I
1.10258 i
1.11238
1.12219 I
14
15
IG
17
18
19
20
21
22
23
24
25
26
Speelflo
gr.ivit/.
1.13199
1.14179
1.15200
1.16222
1.17243
1 . 1 8265
1.19280
1.20344
1.21402
1.22459
1.23517
1.24575
1.25681
Per cent,
of KjCi),.
Specific i Per cent,
gravity. of KgCOj.
I
I
I
27
28
29
30
31
32
33
34
35
36
37
38
89
1.26787
1.27893
1.28999
1.30105
1.31261
1.32417
1.33573
1.34729
1 . 35885
1.37082
1.38279
1.39476
1.40673
40
41
42
43
44
45
46
47
48
49
50
51
52
Specific
gravit/.
1.41870
1.43104
1.44338
1.45573
1.46S07
1.48041
1.49314
1.50588
1.51861
1.53135
1.54408
1 . 55728
1.57048
POTASSII CARBONAS PURUS.
POTASSIUM SEU KALIUM CARBONICUM PURUM.
Pure Carbonate of Potamum. Salt of Tartar, Potassium Carbonate,
Ger. Eohlensaures Kalinm ; Fr. Carboimtc dc potasse ;
Sp. Carbonato de potasa puro.
K^COj; 138.
A white, deliquescent, granular powder, wholly soluble in an
equal weight of water, forming a limpid alkaline liquid, which
effervesces with acid.s, and gives a wliite, crystalline precipitate
with an excess of tartaric acid. When exposed to a red heat, dry
potassium carbonate loses about 16 per cent, of its weight. One
hundred parts of the dry anhydrous carbonate require for com-
plete neutralization 118 parts of citric, and 108.7 parts of tartaric,
acid.
4T») MASCAL OP CHBmCAL ANALYSIS.
Exftminatifiii :
Bicarhoitat^. — A small portion of the 5«-ilt is dissolved in an
equal weight of water, aided bv dipping the test-tube in hot water;
the solution shou.d be clear and complete, and remain so after
o/.ing: tiie separation of a crystalline deposit would indicate
potassium bicarb >n ate. The presence of the latter will also be
indicated in a solution of one part of the salt in three parts of
wat':-r. by the evolution of carbonic acid g:is upon heating the
s^>Mition to Hailing.
Pur'fi^d Pearlash. — A portion of the above-obtained solution
is slijrhtlv sur»ersatu rated with di!ute«l nitric acid, and allowed to
Stand in a corke<J test-tube for several hours: an ensuing gela-
tinous precipitate would indicate s*lictc nc*J : the solution, after
filtering, if necessary, is then tested in separate portions, with
arjrentic nitrate for c?ihriJe, and with barium nitrate for sulphate^
which impurities would indicate the admixture or substitution of
purified pearlash.
Sfetals. — Another portion of the above-obtained aqueous solu-
tion of the salt is tested with hydrogen sulphide in two test-tubes,
the one after suj)ersatu ration with diluted hydnxihloric acid. An
ensuing dark coloration or precipitate in either of the fluids
would indicate metallic impurities.
Potnsshim Xitrate. — The remainder of the concentrated solu-
tion of the salt is supersaturated with diluted sulphuric acid ; the
clear solution is decanted after a while, and divided into two
parts, one of which is mixed with a little ferrous sulphate and
then transferred, by means of a pipette, upon concentrated sul-
phuric acid in a test-tube (Fig. 140); an ensuing purple or brown
POTASSIUM. 477
coloration, at the junction of the two strata of the liquids, would
indicate nitrDte; the other part is tinged slightly blue with solu-
tion of indigo, strongly acidulated with sulphuric acid, and heated ;
ensuing decoloration would confirm the presence of nitrate.
Nitrites may be detected by mixing a little of the aqueous solu-
tion of the salt with an excess of dilute sulphuric acid, and subse-
quently adding a few drops of a solution of potassium iodide and
a little mucilage of starch; a blue coloration will reveal the pres-
ence of nitrite.
Potassium cyanide may be detected in the solution of the salt,
by the addition of a few drops of a solution of ferrous sulphate
and ferric chloride, gently warming, and subsequently slightly
supersaturating the liquid with hydrochloric acid ; the immediate
or gradual formation of a precipitate of Prussian blue will con-
firm the presence of alkaline cyanide.
Calcium and mafjnesium salts, when present in the form of
carbonates, will remain undissolved when the potassium carbonate
is treated with twenty times its weight of water; they may be
otherwise detected in the aqueous solution, previously neutralized
w^ith hydrochloric ac'd, by the addition of ammonia- water, ammo-
nium chloride, and ammonium oxalate; a white precipitate will
indicate the presence of calcium ; the filtrate from the latter, or
the clear liquid if no precipitate was produced, is then tested with
sodium phosphate, when the formation of a white, crystalline pre-
cipitate will reveal the presence of magnesium.
Sodium salts will be indicated, by their property of imparting
a persistent yellow color to the non-luminous flame; the carbonate
may be specially tested for by supersaturating the aqueous solu-
tion of the salt with acetic acid, evaporating to dryness, and
extracting the residue with absolute alcohol ; the filtered alcoholic
liquid is then evaporated to dryness, the residue dissolved in
water, and a solution of potassium meta-antimoniate added; if
sodium carbonate were present, a white, crystalline precipitate of
sodium meta-antimoniate will be produced.
Estimation :
The estimation of pure potassium carbonate may readily be ac-
complished by the method described under purified pearlash, on
pages 474-475.
The United States Pharmacopoeia directs that to neutralize
3.45 grams of potassium carbonate should require not less than
40.5 cubic centimeters of the volumetric solution of oxalic acid
(corresponding to at least 81 per cent, of pure, anhydrous potas-
sium carbonate).
AL OF CIlBMICAt A5ALT9I8.
Fio. U7.
POTASSII CHLORAS-
POTASSUU SEU KALILM CHLORlCUlt.
Ckloratt pf Potitttium. PvlattivM CU*ntU.
Oer. ChlonaoKs KMlinm; Fr. Cblorate de polusc; Sp. Clonto de potkM.
KCIO,; 122.4.
Colorless, transparent, monoclinic prisms or tables (Fig, 147), of
n pearly lustre, anliydrous, and permnnent in the air, and of a
Bpeo. grav. of 2.36 at 17.5° C. (63.5'' P.);
when tbrown upon burning cbarcoal tlicjr
cieflagrate, as lliej also do more or less
violently when triturated or heated willi
rendily combustible siibslanccti, as aul-
pliur, carbon, ptiospborus, etc. Potassium
chlorate melts at 334° C. (B3S.2'' F.) with-
out decomposition; at 362^ C. {660.6* K.)
it begins lo decompose with the evolu-
tion of oxygen, and at 400^ C. (752*' F.) ■
the entire nmonnt of oxveen (3».2 per
cent, by weight) is liberated, leaving be-
hind a neutral residue of potassium chloride (60.8 per ceiil.),
which ift wholly suluble in water. The aqueous sohilion of this
residue yields a white, crystalline precipitate with a oonoenlraled
solution of sodium bitarlrate, and a while, curdy precipitate,
soluble in ammonia- water, with argentic nitrate. When a little
sulphuric acid is dropjied on the crystals of the chlorate, they
become first yellow and then orange-red; with wmcentrated hYdro-
chloric acid the salt becomes likewise decomposed, with the libera*
tion of chlorine and chlorine dioxide; the latter, in contact with
an excess of acid, becoming subsequently decomposed into chlo-
rine and water.
Potassium chlorate ia soluble in 16,5 parts of water at 15° C.
(.'fD" F.), in 2 parts of boiling water, and in 120 parts of alcohol
of 0.635 spec. grav. Its saturated aqueous solution has a cooling,
saline, slightly acerb taste, and, when mixed with couceulratwl
hydrochloric acid, produces a deep greenish-yellow coloration,
with the evolution of chlorine gas. When a few drops of a con-
centrated solution of potassium chlorate, and subsequently a little
concentrated sulphuric acid, are added to a little of a dilute solu-
tion of aniHnc sulphate, upon a watch-glass, the mixture aasumea
a brilliant deep-violet color. With solution of taruric acid, the
concentrated solution of potassium chlorate give a white granular
precipitate.
ExamlnatioiL :
Potaasium NilraCf. — A little of the powdered salt is heated ia
u porcelain crucible lo a full red heat; the residue, when cool, is
i_
POTASSIUM. 479
dissolved in a few drops of water, and the solution tested with
turmeric-paper; a brown discoloration of the paper would indi-
cate an admixture of potassium nitrate. As a confirmatory test,
a few drops of the solution of the residue may be added to a solu-
tion of mercuric chloride; an ensuing yellow precipitate will
confirm the presence of nitrate.
The presence of nitrate may also readily be detected by first
heating a small portion of the salt, in a test-tube, with about twice
its weight of solid potassium or sodium hydrate, and a little water,
in order to ascertain the absence of ammonium salts, and subse-
quently adding a few iron and zinc filings, and again heating; if
ammonium salts were found to be absent, or have been com-
pletely eliminated by the previous heating with caustic alkali, the
odor of ammonia, developed upon the addition of the zinc and
iron, will confirm the i)resence of nitrate.
Potassium chloride and sulphate are detected in the aqueous
solution, acidulated with a few drops of diluted nitric acid, by the
occurrence of a white precipitate, in the case of the former with
argentic nitrate, of the latter with barium nitrate.
Most commercial potassium chlorate occasions a slight cloudi-
ness with argentic nitrate.
Calcivm salts may be detected in the dilute aqueous solution of
the salt, by a white precipitate upon the addition of a few drops of
a solution of ammonium oxalate.
Sodium chlorate will be indicated in the salt by its property of
imparting a persistent yellow color to the non-luminous flame, as
also by its much greater solubility in water and warm alcohol.
It may be extracted by treating a portion of the salt with boiling
alcohol, filtering, and adding to the filtrate a concentrated solu-
tion of tartaric acid ; the potassium will thereby be precipitated,
and, after its complete deposition, the filtrate may be further
examined for sodium.
Metallic impurities may be detected in the aqueous solution of
the salt, acidulated with hydrochloric acid, by a dark coloration
or precipitate upon saturation with hydrogen sulphide, or, after
neutralization with ammonia-water, bv the addition of ammonium
sulphide.
POTA88II CITRA8.
POTASSIUM SEU KALIUM CITRICUM.
Citrate of Pota»sium, Potassium Citrate,
Ger. Citronensanres Kalium ; Fr. Citrate de potasse ; Sp. Citrato de potaca.
K3CJI,0,+ H,0; 324.
A white, granular powder, or transparent prismatic crystals,
containing one molecule (5.55 per cent.) of water; it is deliques-
480
MANUAL OF CHEMICAL ANALVSTS.
cent upon exposure to the air, odorless, of a slightly cooling and
faintly alknliiie taste, and neutral Ju ite action ujHin litmus. When
moderately heated, the salt loses its water, at a higher tempera-
ture it chars, and at a red heat becomes completely decomposed,
with the evolution of empyreumatic, inllainmable vapors, leaving
a blauk residue, consisting of potassium carbonate and carbon,
which strongly effervesces with acids.
Potassium citrate is soluble in 0,6 part of water at 15^ C. (59°
F.), and is very soluble io boiling water; it is very sparingly
soluble in alcohol. lis aqueous solution yields a white, crystal-
line precipitate upon the addition of a, concentrated solution of
sodium bitartrate; upon the addition of a cold solution of cal-
cium chloride the liquid remains clear, but, upon boiling, a white,
granular precipitate is produced, which redissolves for the most
pari upon cooling.
ExaminatioD ;
Polassitim torlrate will be indicated by the separation of a
white, crystalline precipitate, upon the addition of acetic acid to a
concentrated aqueous solution of the salt.
Carbonates, Sulphates, and Chlorides. — The aqueous solution of
the salt is slightly acidulated with nitric acid, wheu eServescence
will indicate carbonates; the acidulated solution is then subse-
quently tested, in separate portions, with barium chloride for
sulphates and with argentic nitrate for clilorides, when au ensuing
whit« precipitate in either instance will reveal the presence of
such impurities.
Metallic impurities may be detected in an aqueous solution of
the salt, acidulated with hydrochloric acid, by a dark coloration
or precipitate upon saturation with hydrogen sulphide, or, after
supcrsatn ration with ammonia- water, by the addition of ammo-
uium sulphide.
EstlmatloB:
Potassium citrate may bo estimated volu metrically by its con-
version into potassium carbonate, and the neutralization of the
latter by means of a normal or standard acid. 5.4 grams of the
salt are ignited in a porcelain crucible, at a red heat, until ga.set<
cease to be evolved; the soluble matter of tbo residue is then
completely extracted with hot water, the solution tillered into u
beaker or small flask, a few drops of litmus solution added, and a
standard solution of oxalic or sulphuric acid (page 82) allowed to
flow into the liquid from a burette until, after being healed to boil-
ing, in order to completely expel the liberated carbonic acid gas,
the liquid assumes a bright cherry-red tint. The excess of acid is
then inversely titrated with a standard solution of potassium or
sodium hydrate (page 87) until the red tint of the liquid is just
changed to a permanent blue. If the above amount of the salt is
employed, the number of cubic centimeters of normal acid wbicb
POTASSIUM. 481
is required for its neutralization, when multiplied by 2, will rep-
resent without farther calculation its percentage purity. With
the employment of other quantities of the salt than that above
indicated, the calculation may be made with the consideration that
one cubic centimeter of normal acid corresponds to 0.108 gram of
potassium citrate, K^C^Hfij -{• 11^0.
POTASSn CTANIDUM.
POTASSIUM SEU KALIUM CYANATUM.
Cyanide of Potassium, Potassium Cyanide,
Gcr. Cyankalium ; Fr. Cyanure de potassium ; Sp. Cianuro de potasio.
KCN; 65.
White, opaque, amorphous masses, or a white, granular, deli-
quescent powder, having a sharp, somewhat alkaline taste, and a
strongly alkaline reaction. It is odorless when perfectly dry, but
emits the odor of hydrocyanic acid u{)on exposure to a moist
atmosphere, in consequence of the absorption of water and car-
bonic acid gas, and the liberation of hydrogen cyanide.
When exposed to a low red heat, with exclusion of the air, the
salt is readily fusible without decomposition, and, upon slowly
cooling, solidifies in the form of cubical crystals; when heated
with exposure to the air, it absorbs oxygen, and becomes partially
converted into potassium cyanate. It is decomposed by all acids,
with the disengagement of hydrocyanic acid.
Commercial potassium cyanide is soluble in 2 parts of water at
15® C. (59® F.), and in its own weight of boiling water; it is but
sparingly soluble in strong alcohol, but is quite freely soluble ju
boiling diluted alcohol, and crystallizes from the latter solution
upon cooling. The aqueous solution has an alkaline reaction,
exhales the odor of hydrocyanic acid, and becomes gradnallv
decomposed by exposure to the air; upon boiling, it is rapidlV
decomposed, with the evolution of ammonia, and the formation
of potassium formiate. The aqueous solution of potassium cya-
nide yields a white, crystalline precipitate upon the addition of a
concentrated solution of sodium bitartrate ; with argentic nitrate, it
yields a white precipitate, which is soluble in an excess of potas-
sium cyanide or of ammonia- water ; and with a few drops 6f a
solution of a ferrous and ferric salt, and the subsequent addition
of hydrochloric acid in slight excess, a precipitate of Prussian blue
is produced. It produces precipitates in solutions of the salts of
most of the heavy metals, which, however, for the most part, are
soluble in an excess of potassium cyanide, with the formation of
crystallizable double salts.
31
The detection and isolation of potassium cyanide in subjects nf
forensic in veatigation depends upon thecliminaiion of hydrocvanic
acid in contact with stronger acids, and the same method is tliere-
fore to be pursued, and the same precautions observed, as described
in detail under hydrocyanic acid, on pages 161 to 163.
Examination:
Polassinm coThonale, which is nsually present in small amount,
will be indicaied in the aqueous solution of the salt by eft'erves-
cence upon the addition of dilute hydrochloric acid. The acidu-
lated solution thus obtained may subsequently be tested with a
drop of a solution of ferric chloride ; a bine precipitate will indi-
cate /Vrrocyi liiye, a deep blood red coloration, sulpkon/anfde.
EBtimatlon:
Since commercial polasaium cyanide always contains a greater
or less amount of impurities, and as its value depends upon the
percentage amount of pure cyanide, the determination of the latter
becomes necessary, and may be readily accomplished volumetri-
callv by the following method, the principles of which have been
explained on pages 100-101,
0.65 gram of the salt is dissolved iu about 100 cubic eentime-
terB of water, in a beaker, a few drops of a solution of potassium
hydrate added, or sufficient to imparl to the liquid a distinct alka-
line reaction, and subsequently a few drops of a saturated solution
of sodium chloride. A decinormal solution of argentic nitrate
{page 98) is then allowed to flow into the liquid from a burette
until, with constant stirring, a. permanent cloudiness of tiie liquid
is just produced. The number of cubic centimeters of silver solu-
tion which is required to produce this effect, with the employ-
ment of llie above-stated amount of potassium cyanide, when
multiplied by 2, will represent the percentage purity of the salt.
With the employment of other amounts of the sail than that
a^iove stated, the calculation may be made with the consideration
that one cubic centimeter of the decinormal silver solution, in
accordance with the described process, corresponds to 0.013 grain
of pure potassium cyanide.
The United States Pharmacopoeia directs that if 0.65 gram of
poinssium cyanide be dissolved in 12 cubic centimeters of water,
and volumetric solution of argentic nitrate be gradually added,
the precipitate first formed should dissolve on stirring, and a per-
manent precipitate should not appear until at least 45 cubic centi-
meters of the volumetric solution have been used (corresponding
to at least 90 per cent, of pure potassium cyanide).
This iooh is the propcri J __
COOPER MEDICAL COLLIw.-.
SAN FRANCISCO. OAt„
onrf w ™rt to f>e rt-mtn^d fiom t^t
POTASSIUM.
FOTA8SII ET SODII TARTRAS.
POTASSIUM ET SUDRIM TAItTAHK TM. NATRH) - KAI-IUM
TARTARICUM. SODIUM TARTARATUM. TARTARUS NATRO-
MATDS.
Roehellt Salt. Beignelle Salt. Potatiiam nnrf Sodium TnrlraU.
Ot^r. WeinaaurcB Kaiium-Nnlrium ; Fr. Tnrirato de polasie el dc soude ;
S[). Tnrtraio <ie potnsa y sow.
' ' ' * CH(OH)-CO-ONb
Large, colorless, transparent, prismatio crystals, belonging to
the rhombic system, the fauea of which are unei^ually developed ■
(Fig. 14b); tboy contain lour molecules (25,53
per cent.) of water of crystallisation, and are Pio. U8.
slightly efflorescent in dry air.
The salt occurs in commerce generally
ground, na a snow-white powder. When
quickly heated to about 75^ C. (167** F.), il
melts in its water of crvstallizalion, and at
100° C. (212= F.) loses 3 'molecules of water,
the remaining; molecule of water being elimi-
nated at 130° C. {ZGii" F.), at which tempera-
ture the salt begins to decompose ; at a higher
temperature it chars and is decomposed, with
the evolution of inflammable vapors and the
odor of burnt sugar, and, on moderate ignition,
leaves a blackened residue, which consists of a n
sium and sodium carbonates with carbon, and which colors tur-
meric-paper brown, efl'ervesces wiih acids, and Jnipurts a yellow
color to the non-hiniinous flame when heated upon the looped end
of n platinum wire (distinction from potassium tartrate).
Potassium and sodium tartrate is soiublo in 2.5 parts of water
at 15° C. (59° F.), and in much less than its own weight of boil-
ing water, but is insoluble in alcohol; its aquDons solution is
neutral, has a mild, cooling, saline taste, and forms a white, gran-
ular precipitate with acids and with solutions of acidulous salts.
When dissolved in 8 parts of water, and dilute acetic acid is added
to the lic|uid, a white, crystalline precipitate is gradually produced
(distinction from sodium tartrate); with argentic nitrate it yields
a white precipitate, which becomes black on boiltag.
Examination :
A portion of the salt is dissolved in three times its weight of
warm water; the solution should be clear and complete, and
remain so after cooling ; it should not act upon litmus-paper, nor
eftiervesce upon the addition of hydrochloric acid (evidence of the
absence of sodium carbonate wr bicarbonate).
lixlure of poias-
484 HAVTAL or CBBUtCAL ASALT8I8.
Chlorides and tidphaUs may li- deiecteU by a white precipitate
vrhen the diluted eoluCinu of the sail, ftcklulalod witli uttric acid,
u tested in Kparaie purtious, wiiK argentic aitrale for the former,
and with barium nitrale for the Utter. In caee the solutiou Befna-
rates granalar polassium bitartraie upon the addition of the acid,
sufficient hot water is added lo rediasolre the precipitate before
adding the reagent.
rafcMfin talu are detected in the dilated solutioo, by means of
ammonium oxalate.
Ammonitim Malts mar be detected by the odor of ammonia,
when the mlt is heated, in a test-tuW, with a solution of potas-
sium or sodium hydrate, and by the development of white fumea,
when a glass rod, moistened wilh acetic acid, is held over ihe
mouth of the tube.
MftaVic impurities are detected in the concentrated solution of
the salt, acidulated with hydrochloric acid, and filtered, if neoes-
wwy, by a dark coloration or precipitate upon saturation wilh
'lyuToj
hydrogen suljihide, or, after ueutralization with ammonia- water,
by the addition of ammonium sulphide,
CryMtaWzetl potassium and sodium tartrate, being in appearance
somewhat similar to crystallised borax and alum, and tuerofora
liable to incidental mi^^take, mar readily be distinguished from
cither of these substances, in addition to its physical characters,
by its taste, by its neutral reaction^alum be'ng acid, borax alka-
line, and by tfio black alkaline fuse upon incineration, while both
borax and alum swell up to a porous mass, and yield a white or
colurlcNS fuse.
EBtimatioB:
.^.n2.^ grams of the salt are ignited in a porcelain crucible, at a
red heal, until gases cease to be evolved ; the alkaliue residue is
then extracted with warm water, the solution tiltered into a beaker,
a few drops of litmus solution added, and titrated, bv the aid of
heat, wilh a standard solution of oxalic or sulphuric acid (page 82),
aa descnbed nnder potassium carbonate, on page 474. The num-
ber of cubic centimeiers of the normal acid solution which ^s
thus required for the exact neutralization of the li<]uid, when
mnltiplicd by 4, will indicate, without further calculation, the
percentage purity of the salt. By theemployment of other quaD-
tilies of the salt than precisely that above stated, the calculation
may also readily l»e made with the consideration that one cubic
centimeter of the normal acid solution corresj>ODds to 0.141 gram
of pure crystallized potassium and sodium tartrate.
I
POTASSIUM. 485
POTA88II FERROCTANXDUM.
POTASSIUM SEU KALIUM PERROCYANATUM.
FerrocyaniiU of Potassium. Yellow Prusnate of Potassium. Potassium
Ferrocyanide.
Ger. Ferrocyankalium ; Fr. Cyanure de fer et de potassium ;
Sp. Ferrocianuro de potasio.
K,Fe(CN),+3H30; 421.9.
Larpre, transluceat, yellow, tabular crystals, derived from an
octahedron with a square base (Fig. 149) ; they cleave with facility
in a direction parallel to the base of the octa-
hedron, have a peculiar toughness and flexi- ^^^' ^^^•
bility, and the specific gravity 1.83. The
crystals contain three molecules (12.79 per
cent.) of water of crystallization, and undergo
no alteration in pure air at ordinary tempera-
tures, but when heated to 60® C. (140° F.)
they begin to lose their water of crystalliza-
tion, which is completely eliminated at 100° C. (212^ F.), leaving
the anhydrous salt in the form of a white powder ; the latter,
upon exposure to a red heat, is decomposed with the evolution of
nitrogen, leaving a residue consisting of ferric carbide and potas-
sium cyanide. When heated with dilute sulphuric acid, hydro-
cyanic acid is evolved.
Potassium ferrocyanide is soluble in 4 parts of water at 15^ C.
(59° F.), and in 2 parts of boiling water ; it is insoluble in alcohol.
Its aqueous solution has a mild saline taste, gives a white, granu-
lar precipitate witli a saturated solution of sodium bitartrate, and,
when diluted, a blue one with ferric, a brick-red one with cu[)ric,
and a white one with ferrous and with plumbic salts; it is not
acted upon by hydrogen sulphide or ammonium sulphide, by tan-
nic acid, nor by the alkaline hydrates and carbonates. When the
solution is exposed for some time to the action of light, Prussian
blue is deposited, and, by long-continued boiling, with exposure
to the air, ammonia is given off, and the liquid becomes alkaline.
Examination :
Foreign salts are indicated when the potassium ferrocyanide
does not yield a complete and clear solution with four parts of
water.
Carbonate is indicated by effervescence of the concentrated solu-
tion upon the addition of acetic acid, or upon placing fragments
of a crystal in diluted sulphuric acid.
Sulphate is detected, in the diluted solution, acidulated with
nitric acid, by a white turbidity with barium nitrate.
Chloride may be detected, when a mixture of 1 part of the ex-
siccated salt with 3 parts of potassium nitrate (free from chloride)
48G
HASDAL or OUBHICAL ANALYSIS.
hikI 10 parts of anhydrous sodium carbonate ib heated nearW
redness in a porcelain crucible ; when cool, the whole is dissofv)
ill water, the filtered solution supersaturated with nitric aoUM
and tested with argentic nitrate, which will indicate chloride I
a while precipitate.
POTASSII HYDRAS.
Pure Caattie Poiaih. Palana.
Pota»num HgdriiU,
istlquc ;
Lneu trail
KOH; 56.
A white, opaque, granular powder, or, when fused, white, seinit
trau.'^parent plalci or cylindrical sticks, of a fibrous fractura
exposed to the air, it ab.sorbs water and earbonie acid, and grad
uahy deliiyieaces. It. melts below a red heat to a clear oil^ liquid
and volatilizes uuchauged, in the form of white vapors, wliei
more strongly ignited; when introduced into the oou-lumiooui
flame, it imparts to the latter a violet color.
Potassium hydrate is soluble in 0.5 part of water and in 2 parti
of alcohol at 15° C. (50" F.), with the evolution of beat, and ii
slightly soluble in ether ; when the concentrated aqueous solutioa
ia cooled, the hydrate, K0II-t-2II,0, is deposited in transparent|,
colorless, acute rbonibohodral crystals. Its aqueous solution hat'
a soapy feel, a burning, corrosive taste, and a strong alkaline r*
action ; it gives a grayish-brown precipitate with argentic nitratog
soluble in am mom a- water, and precipitates from their solutioiHI
most metallic oxides, several of which are redissolved by an
excess of the potassium hydrate; when dropped into solution o"
tartaric acid, it produces a white, crystalline precipitate, which ii
redissolved by an excess of the alkali; it decomposes ammoniua
halls with the evolution of ammonia.
Examination :
Potassium hydrate must aft'ord a clear and nearly complete
solution when treated with about five times it weight of alcohol;
the insoluble residue will be in proportion to the amount of
foreign salts present.
Sotliitm hydrate, although usually present in small amount, cnaj- ■
be detected when contained in any conwderable proportion by tiutm
following method. A weighed amount of potassium hydrate is-l
dissolved in ten limes its weight of water, the .solution exactljpl
neutralized with Urtaric acid, and subsequently as much tartAriO'l
acid again added as was required fur the neutralization of Uiaf
POTASSIUM. 187
alkali ; the solution is then diluted with alcohol until the separa-
tion of potassium bitartrate no longer ensues, and finally filtered.
The solution, which will contain the sodium in the form of bitar-
trate, is evaporated to dryness, the residue ignited, and the ignited
mass, consisting of sodium carbonate and carbon, dissolved in
water, and filtered. The filtered solution, after neutralization
with nitric acid, will then afford upon evaporation rhombohedral
crystals of sodium nitrate, which impart a yellow color to the
non-luminous flame. The amount of sodium hydrate may also be
quantitatively determined, by the neutralization of a definite
amount of the sodium bitartrate solution with a normal solution
of potassium or sodium hydrate (page 82). The number of cubic
centimeters of normal alkali solution which is required for this
Curpose will be in direct proportion to the amount of sodium
ydrate contained in the solution under examination.
Silicates, as also many foreign salts, will be indicated by a pre-
cipitate, or by the separation of a heavy aqueous layer, when a
solution of the potassium hydrate in two parts of water is dropped
into alcohol.
Carbonate may be detected when portions of a concentrated
aqueous solution of the hydrate are dropped severally into acetic
acid and into lime-water ; effervescence with the acid, and a white
turbidity with the lime-water, would indicate carbonate.
Nitrate is indicated by ensuing decoloration of the liquid when
a little of the aqueous solution which has been mixed with an
excess of dilute sulphuric acid, and tinted blue with one drop of
indigo-solution, is gently heated.
Chloride and sulphate are detected in the diluted solution, super-
saturated with dilute nitric acid, by testing it, in separate por-
tions, with argentic nitrate for chloride, and with barium nitrate
for sulphate.
Aluminium salts and phosphoric acid may be detected in the
diluted solution, after supersatu ration with hydrochloric acid, by
the addition of ammonia- water in slight excess, and after filtering,
if a precipitate be formed, by the subsequent addition of test mag-
nesium mixture; a white, gelatinous precipitate with the ammo-
nia-water would indicate aluminium salts, and a white, crystalline
one with the latter reagent, occurring at once or after several
hours, phosphoric acid.
Metallic impurities are detected by a dark coloration or tur-
bidity of the solution, when saturated with hydrogen sulphide,
and, in another portion of the solution, after previous supersatu-
ration with hydrochloric acid.
Estimation :
2.8 grams of dry potassium hydrate are dissolved in about 20
cub^c centimeters of water, in a beaker, a few drops of litmus
solution added, and a standard solution of oxalic or sulphuric
acid (page 82) allowed to flow into the liquid from a burette,
UAMUAL or OHSHICAL ASAI-TStS.
until the blue liitt of the liquid is just chaugetl u> n pcnnaaent
pink. The iiuinl>er of cubic ceniimet^ni of normal aoicl solu-
tion which is thus required for the exnct neutraliuttion oF ihe
above amount of potassium hydrate, wheu multiplied by 2, will
represent, without further calculation, its peroentage purity.
By the employment of other amounu of the hydrate, the calcula-
tion may readily be made, with the cousideration thst one cubic
ceutimetcr of the normal acid solution corresponds to O.U5t( gram
of iiurc potassium hydrate.
If the potassium hydrate contains carbonate, the above estiioa-
lion will only be strictly correct, when in a weighed nrnuuut of
the hydrate the amount of carbonic acid is deienninetl, as de-
scribed on pages 86-80 ; for 1 part of carbonic acid, '2.o4o parts
of potassium hydrate arc deducted from the found amount ot tbe
latter, and the remainder then caluulated as pure poiaasiuni
hydrate.
For the determination of the strength of aqueous solutions of
potassium hydrate, as based upon the specific gravity of the latter,
see Liquor Potasate, page 4l0.
FOTASBH HTDRAS CR1TDUS.
POTASSIUM SEU KALIUM [lYDRICUM CRUDDM.
Fused, heavy, compact masses, of a stony appearance, fracture,
and hardness, of a soapy feel, burning, corrosive taste, aud a
destructive action on vegetable and animal matters ; its color is
mostly greenish or brownish-gray ; it is deliquescent, and rapidly
absorbs water and carbonic acid. Heated to rodueBs,it fuses, but
remains unchanged; at a very high heat it ia volatile.
Crude pota.sh dissolves, for the most part, in water and in alco-
hol, with evolution of heat, leaving a more or less considerable
residue of impurities; the decauted solution gives a grayish brown
precipitate with argenlie nitrate, soluble upon the addition of
ammonia- water.
The insoluble impurities of crude potash conaisl chiefly ofcar-
bonntes, sulpliales, silicates, chlorides, and ferric and manganic
Ezaininatlon :
In order to ascertain the nature of the impurities, a portion of
the crude potash is triturated and dissolved in twice its weight
of tepid water, and the whole is allowed to subside in a conioal
POTASSIUM. 489
glass vessel ; the clear solution is then mixed with twice its
volume of strong alcohol, and the mixture allowed to stand for
several hours; the solution is then decanted from the precipitate,
as far as practicable, and the latter dissolved in hot water; when
cool, this solution is filtered, and the insoluble residue washed
with a little water, and preserved upon the filter for further
examination. The obtained aqueous solution may be examined
as follows:
Carbonate and silicate are recognized on dropping a little of the
solution into a test-tube containing a mixture of equal parts of
water and concentrated nitric acid; the former will be indicated
by effervescence, the latter by a white, gelatinous turbidity, ensu-
ing at once or after some hours.
Sulphate and chloride may be detected, in separate portions of
the solution, by supersaturating it with nitric acid, and subse-
quently testing with barium nitrate for sulphate, and with argentic
nitrate for chloride.
Sulphite and hyposulphite are indicated by the occurrence of an
insoluble residue, when a portion of the solution is precipitated
with argentic nitrate, and tlie precipitate is treated with ammonia-
water.
Nitrate is detected, in a portion of the solution, after the ad-
dition of an excess of dilute sulphuric acid and one drop of solu-
tion of indigo; the blue tint will disappear upon warming, if
nitrate be present.
Phosphate may be detected by a white, crystalline precipitate,
when the solution is supersaturated with hydrochloric acia, then
mixed with an equal volume of ammonia-water, and subsequently
tested with magnesium sulphate.
Metallic impurities are recognized by a dark coloration or pre-
cipitate, when both the alcoholic solution and the aqueous solu-
tion of the residue from the alcoliolic one are tested separately
with hydrogen sulphide, as also after having been previously
supersaturated with hydrochloric acid.
The residue remaining from the solution in alcohol, and pre-
served upon the filter, is washed with a few drops of alcohol, then
dissolved upon the filter in diluted hydrochloric acid, and subse-
quently neutralized with ammonia water; this solution is then
tested, in separate portions, with ammonium oxalate for calcium^
and with barium chloride and a few drops of hydrochloric acid
for sulphate.
The estimation of crude potash may be accomplished volu-
raetrically by the method described for pure potassium hydrate,
on pages 487-488.
490 MANUAL OF CHEMICAL ANALYSTS.
POTASSn H7P0PH08PHI8.
POTASSIUM 8EU KALIUM HYPOPHOSPHOROSUM.
Hypophosphite of Potassium. Potassium Hypophosphite,
Ger. Unterphospkorigsaures Kaltum ; Fr. Hypophosphite de potasse ;
8p. Hipofdsfito de potasa.
KH,PO,; 104.
White, opaque, crystalline masses, or hexagonal tables, or a
white granular powder, very deliquescent, and neutral in its
action upon litmus; when heated in a perfectly dry test-tube,
the salt first loses adhering moisture, then evolves spontaneously
inflammable hydrogen phosphide, and burns with a bright yellow
flame ; when evaporated to dryness, in contact with nitric acid,
it detonates violently.
Potassium hypophosphite is soluble in 0.6 part of water, and in
7.3 parts of alcohol at 15° C. (59° F.) ; in 0.3 part of boiling water,
and in 3.6 parts of boiling alcohol ; but is insoluble in ether. The
aqueous solution possesses a sharp, saline, and slightly bitter
taste, and yields a white, crystalline precipitate on the addition of
a concentrated solution of sodium bitartrate ; with argentic nitrate
it yields a white precipitate, which rapidly turns brown and
black with the separation of metallic silver; when acidulated
with hydrochloric acid, and added to excess of solution of mer-
curic chloride, it first produces a white precipitate of mercurous
chloride (calomel), and, on further addition, metallic mercury is
separated.
Examination :
Calcium salts will be detected by an ensuing white precipitate
on the addition of ammonium oxalate to an aqueous solution of
the salt.
Carbonates will be detected by effervescence of the solution on
the addition of an acid.
Chlorides and sulphates will be detected in the aqueous solution
of the salt, acidulated with nitric acid, by a white precipitate
when tested, in separate portions, with argentic nitrate and barium
chloride.
Phosphates will be indicated in the aqueous solution of the salt
by the formation of a white crystalline precipitate, either at once
or upon standing, on the addition of test magnesium mixture.
This hool'is thejv'o^
COOPER MEDICAL COI.Ll.C.f
SAN FRANCISCO. CAU
Ovd M not tn },t* r''»/^' '' ^ ''fil ^''^
I \ I , " f I t f ■•'•■'•>• ****
POTASSIUM. 491
POTASSn lODIDUM.
POTASSIUM SEU KALIUM lODATUM.
Iodide of Potassium. Potassium Iodide.
' Gcr. Jodkalium ; Fr. lodure de potassium ; Sp. loduro de potasio.
KI; 165.6.
Colorless, anhydrous, semi-transparent, or opaque crystals,
cubical, or sometimes elongated in form, permanent in dry, but
slightly deliquescent in moist, air, and having a spec. grav. of
2.97. When exposed to heat, potassium iodide decrepitates, and
fuses below a rea heat ; on cooling, it solidifies into a crystalline,
jiearly mass, without loss of weight, except humidity ; at a full
red heat, it is slowly volatilized, without decomposition. When
a few fragments of the salt are heated in concentrated sulphuric
acid, or, in a dry test-tube, with a little potassium bisulphate,
violet-colored vapors of iodine are evolved ; and when dissolved
in a little water, a few drops of chlorine-water added, and the
mixture subsequently shaken with half its volume of chloroform
or carbon bisulphide, these will acquire a purple or violet color.
Potassium iodide is soluble in 0.8 part of water, in 18 parts of
alcohol, of 0.835 spec, grav., and in 40 parts of absolute alcohol at
15^^ C. (59^ P\), in 0.5 part of boiling water, and in 6 parts of
boiling alcohol, and is also very freely soluble in warm anhydrous
glycerin. The aqueous solution possesses a pungent, saline taste,
a neutral or feebly alkaline reaction, and gives, with an excess of
tartaric acid, a white, granular precipitate; with argentic nitrate,
a yellowish one, which is insoluble in diluted nitric acid, and
almost insoluble in ammonia-water, but becomes white with the
latter; and a vermilion-red precipitate with mercuric chloride,
soluble in an excess of either the solution or the reagent ; it gives
a violet-blue color with a little mucilage of starch, upon the sub-
sequent addition of a few drops of chlorine-water (distinction
from potassium bromide and chloride), and a white, crystalline
precipitate with a saturated solution of sodium bitartratc.
Examination :
Water, which may be contained as interstitial moisture in the
crystals, is recognized, and may be quantitatively determined, by
the loss of weight upon drying a known weight of the powdered
salt at 100^ C. (212° F.).
Impurities and Admixtures. — In order to obtain for examina-
tion an average representation of the iodide, several grams of
smaller and larger crystals are selected from the bulk of the salt,
and triturated to agranular powder, part of which may serve for
the following tests : Onegram of it is-dissolved in an equal weight
of water; the solution formed must be. clear and complete, and
remain so after the addition of several times its volume of strong
493 BiSUAL OF CHBSIIOAL AHALYSIS.
or absolute alcohol; an ensuing turbidity or crystalline deposit
would indicate foreign salts (carbouate, sulpbate, iodatc, aitrate);
if tliis precipitate is considerable, it may bu collected upon a filter,
wiiabca witb a few drops of alcohol, and then dissolved in a faw
droiis of warm water; the obtained solution may be tested for
earlionate with turmeric-paper, or by allowing one or two drops
of it to fall into concentrated hydrochloric acid ; a brown colora-
tion of the paper, and eflervescence witb the acid, will indicate
the presence of oarbonate; the reRt of the solution in tiuidulated
with a few drops of hydrochloric acid, and tested for tulphaU
with one drop of barium chloride, and subsequently, for nitrate,
by the addition of a little sulphuric acid and a drop of indigo
solution, and heating.
Potassium, iodnte may be detected in the aqueous solution of
the salt, by adding a few drops of mucilage of starch, and then a,
few drops of a concentrated solution of tartaric acid, insufficifiBt
t" cause a precipitate; if iodate be contained in the salt, a violet
coloration of the liquid will occur at once. Or the aqueous sola-
tion, mised with a few drops of concentrated solution of tartaric
acid, may be shaken witb a little chloroform, which will assume
a red color when iodalc is present.
I«Kiate may also be recognized in potassium iodide by dropping
a crystal of tartaric acid into a strong solution of the iodide in
previously boiled, distilled water, and allowing it to remain nt
rest for several minutes ; if iodate be present, the crystal will be
enveloped after that time in a yellowish-white zone.
Carlonate may be detected by a white turbidity when the
aqueous solution of the potassium iodide is mixed with twice its
volume of lime-water, and will also be indicated by a strongly
alkaliue reaction, when a few fragments of the salt arc ptaoea
upon moistened red litmus paper.
Sulphate may he detected in the diluted solution of the iodide,
previously acidulated with hydrochloric acid, by a white precipi-
tate with barium chloride.
Nitrate may be detected in the aqueous solution, if the salt be
free from iodalfi, by the addition of a few drops of mucilage of
starch, and subsequently adding a little of lliis liquid to a mix-
ture of zinc and dilute hydrochloric acid, in whicn the develop-
ment of hydrogen is actively taking place; if any nitrate be pre-
sent, the liquid will gradually assume a reddish- violet or blue
color. If iodate be present, the presence of nitrate may also be
determined by completely precipitating a solution of the salt with
argentic sulphate, Jiltering, and adding to the filtrate, in a tost-
tube, a concentrated solution of ferrous sulphate, and afterwards
concentrated sulphuric acid, so as to form two layers (Fig. 146,
fi. 476) ; a dark-brown coloration at the line of contact of the two
iquids will then reveal the presence of nitrate.
Chloride and hromide are detected by dissolving 1 gram of the
salt in 10 grams of ammonia-water, and agitating the solutioti
L
POTASSIUM. 493
with a solution of 1.1 grams of argentic nitrate in 20 grams
of water ; the mixture is then filtered, and the filtrate super-
saturated with 8 grams of strong nitric acid ; since ammonia-
water dissolves only traces of argentic iodide, the transparency of
the liquid must be not at all, or only slightly, impaired ; a white
turbidity, subsiding to a precipitate, would indicate the presence
of more than about 0.5 per cent, of chloride or bromide. In order
to distinguish these, the precipitate is collected upon a filter and
washed with a little water, until this ceases to redden blue litmus-
paper ; the filter is then pierced by a glass rod, and the precipi-
tate rinsed into a test tube; after subsidence, the water is, as far
as possible, decanted, and chlorine- water added and agitated with
the precipitate ; since chlorine decomposes argentic bromide, dis-
solving the disengaged bromine with a yellow color, bromide will
be recognized by a more or less deep yellow color of the fluid,
while argentic chloride remains unchanged. When chloroform
or ether is then added to the fluid and agitated, it will absorb the
bromine and the yellow color from the water.
A confirmatory test for the recognition of bromide is, to add to
a solution of the salt an excess of solution of cupric sulphate,
and subsequently so much of a saturated solution of sulphurous
acid as to impart its strong odor to the mixture, and until the
brownish color of the mixture has disapj)eared ; the liquid is
then filtered, a little chloroform added, and subsequently chlo-
rine-water in very slight excess, in order to effect the oxidation
of the sulphurous acid, and the mixture well agitated ; after sub-
sidence has taken place, a yellow color will have been imparted
to the chloroform if bromide is contained in the salt.
Iron and zinc may be detected in the aqueous solution of the
salt by the addition of a few drops of a solution of potassium
ferrocyanide ; a blue coloration will reveal the presence of iron,
and a white precipitate that of zinc.
Estimation :
A quantitative estimation of the purity of potassium iodide
may be made by dissolving 1 gram of the salt in 10 grams of
ammonia-water, and adding to the solution a solution of not less
than 1.1 grams of argentic nitrate in 20 grams of water ; the mix-
ture is then well agitated, filtered, and the precipitate of argentic
iodide well washed with water, and finally dried at 100° C. (212® F.)
until of constant weight. If the potassium iodide was pure,
1.415 grams of argentic iodide should be obtained, or, 100 parts
of argentic iodide correspond to 70.65 parts of potassium iodide.
The estimation of the j)urity of potasvsium iodide may also be
accomplished volumetrically by the following method : This is
based upon the fact that mercuric chloride precipitates from a
solution of potassium iodide, red mercuric iodide, which is soluble
in an excess of a solution of potassium iodide with the formation
of a soluble double salt, and the solution of the latter again yields
494 MANUAL OF chbuical analysis.
upon tlie subsequent addition of mercuric cliloride a prccijiitAte
of mercuric iodide.
2KI + HgCl, - Hfrl, + 2KC1
Hgl, + 2KI - HgKJ,
or 4KI + HgCi, - li-KJ, + '2KCI.
664 271
(5) (2.03)
2.03 grams of mercuric cblnride are dissolved in water to the
mcafure of 100 cubic centimeters, and 5 grams of tbe potasfiium
iodide under examination are likewise dissolved in water to the
measure of 100 cubic centimeters;* 10 cubic centimeters of the po-
tassium iodide solution are then brought into a beaker, which is
placed upon a sheet of white paper, and the above sohition of mer-
curic chloride allowed to flow into the liquid from a burette until,
with constant stirring, a permanent precipitate of mercuric iodide
is just produced. The number of cubic centimeters of the mer-
curic chloride s<ilution which are required to produce this reac-
tion, when multiplied by 10, will represent the percentage amount
of pure potassium iodide contained in the salt. The accuracy of
the result of the estimation by the above methixi is not influettced
by the presence of chloriiie or uf considenible amounts of bromide.
POTA8BII NITRAS.
POTASSIUM SKU KALIUM XITRICUM.
miratc of Potofiu,
Oer. Salpeler
Biiliprlre. Ifttrt. Pol,
KN0,5 101.
I'inm KilraU.
; 8p. Nit rata
Lonji, striated, ais-sided, prismatic crystals, belonging to the
rhombic system (Fig. 150), colorless and transparent, and of a,
spec, grav- of 2.0; or a while, granular ]>owder, pcrmaneut in the
air. It melts at about 340" 0.(642.2" F.) without decom|K)9itioii,
and solidities on cooling to a white, opaque, crystalline mass: at
a red heat, it k decomposed with the evolution of oxygen and
nitrogen gases, and leaving a residue consisting principally of po-
tassium nitrate, oxide, and dioxide, which omits nitrous vapors on
the addition of sulphuric acid. When thrown upon burning coals,
* Tlie rpsiilig nilHlned by iliie metlioii nrt- rcmlcrwl more accnraiu when, in-
McailordiBiiolviiig tlie mercuric clilnride ami puisfieiuiii iodide in wnior, alcobol
nf 17.5 per cenl, liy vohitne is employed. From ilie Tonnula x ^ - — '-^ , in
wliicli « rcjiresMitH llicpercrniAj:e Birciigtli of lUe olcolitil lo be diluted, ilie vol-
ume of bIchIioI mny be cnlciilated wUicli miisl be mlded lo Uif water in order to
obtttin 100 pnrii of aleoliol of IT.B per ceut. by volume.
POTASSICM. 495
it deflagrates with triglit scintillatioua, leaving an alkaline resi-
due, which, when heated u|inn the looped end of a plaliimm-wire,
impnrts a violet color to tlie non-luminous flame.
PotaBsium nitrate is Boliible in 3.8 parts of water F"g. 150,
at 15° C. (59° F.), and in 0.4 part of toiling water;
it is far less soluble in glycerin, and almost insolu-
ble in alcohol ; its aqueous solution is neutral, lias
a cooling, saline taste, and forms a while, granular
precipitate with a concentrated solution of sodium
bitartrate; a few drops of it mixed with a solution
of ferrous sulphate, and carefully placed upon con-
centrated sulphuric acid (Fig. 146, page 476), give
rise to the formation of a dark coloration upon the
line of contact between the two fluids.
ExaminBtion :
Chloride and sulphate are detected in the diluted
solution of the salt, acidulated with nitric acul,
by ensuing white precipitates when tested in two
separate portions, with argentic nitrate for chloride, and with
barium nitrate for sulphate.
Chlorate ia indicated by a yellow coloration, and the evolution
of chlorine, when a concentrated solution of the potassium nitrate
is mixed and gently warmed with an equal volume of concentrated
hydrochlonc acid.
Calcium and ma</nesiiim salts arc detected by a white turbidity
when the diluted sfjlution is warmed with dilute solution of stxHum
carbonate; they may be distinguished by adding a little ammo-
nium chloride and ammonia-water to the dilute solution of the
salt, and testing it, in separate portions, with ammonium oxalate
for calcium, and, after filtration, if necessary, with sodium phos-
phate for magnesium.
Potnseium nitrite may be detected by a violet or blue colora-
tion, when to a solution of the salt a little mucilage of starch, a
few drops of a solution of pure potassium iodide, and subsequently
dilute sulphuric acid are added.
Sodium salts will be indicated by their property of imparting
a persistent yellow color to the non-luminous flame, as also by a
wnite, crystalline precipitate, occurring either at once or after
several hours, when a concentrated cold solution of the salt is
tested with a few drops of solution of potassium antimoniate.
When thus indicated, tlie extent of such n contamination may he
determined by repeatedly extracting a weighed amount of the
powdered salt with boiling alcohol of the spec. grav. 0.890; the
filtered liquid will then leave, upon evaporation, a residue, con-
sisting principally of sodium nitrate with a little potassium
nitrate. The residue is then dissolved in a little water, acidulated
with hydrochloric acid, and the potassium completely precipitated
by the addition of platinic chloride and a little alcohol ; the liquid
is subsequently filtered from the precipitate of ]>otassio-platin;c
496
MANUAL OF CHEMICAL A!?ALT6I6
chloride, the excess of platiriuin remoTed bv Batnration vith
hydrogen sulphide, and, after fihrati<m. evaporat^^ to dryness.
i;rnited at a gentle heat, and the residue finally weighed a? ?oi um
chloridt/: 1(>0 j»arts of which cnrresj;>ond to 145.3 parts of sc»dium
nitrate.
If potassiunn nitrate contains even a few j">er cent, of sodiam
nitrate, it will liave a moist appearance, arising from the deli-
quescent character of the latter salt.
Metallic impurities will be indicated by a dark cc»lora:ioTi or
precipitate, when a solution of the salt, acidulated with hydro-
chloric acid, is tested with hydrogen sulj>hide. and. after filtration,
if necessarv, and neutralization with ammonia- water, bv the sub^
sequent addition of ammonium sulphide.
Estimatioii :
The pro]>er amount of nitric acid contained in the salt may be
conveniently determined by its ignition in a small porcelain cru-
cible, at a red heat, with an equal weight of concentrated sulphuric
acid, until it ceases to lose weight. One gram of the salt, if j.»er-
fectly pure, will thus afford a residue of potassium sulphate,
weighing O.^I^O gram.
TliC determination of the proper amount of p^>tassium in the
salt, when free from s^xlium, may also readily be accomplished, as
follows. A weighed amount (about 5 grams) of the potassium
nitrate contained in a porcelain capsule, is repeatedly evaporated
with a solution <^»f ab<jut *S grams of c»xalic acid to dryness, or
until C'»mp!«.'tely converted into potassium oxalate. Tlie latter is
then, by ignition, converted into rotassium carbonate, which is
dissolved in water, and. after the addition of a few drops of litmus
solution, titrated with a standard solution of oxalic or sulphuric
acid (j»a;re S2), as described under potassium carbonate, on ]>age
474. The calculation may then be made with the consideration
that one cubic centimeter of normal ac d cv»rresponds to O.OOi*
gram '»f potassium carbonate, or, as its equivalent, O.lOl gram of
pure potassium nitrate.
Tahle of the pfrrentdfjf^ $trmgth of solutions of Potassium Nitrate of
different fp^cijic ^rarities.
Teniperaiure 15^ C. (51>- F.).
Per « enl.
Sl'^rjflc
pi»r r<»ut.
bpeciflc
Per cent.
spec flc
of K.No...
gtuv.ty.
uf K.NO .
KraOcy.
i^'K-Nn,
gravity.
1
l.(K»041
8
1.05197
ir.
1.09977
2
1.0128:{
M
1.05861
16
1.10701
3
1.01924
10
1.0C524
17
1.114S6
4
1.02r,0«
11
1.07215
18
1.12150
»
•)
1.0:^207
12
1.07905
19
1.12875
G
1 .o:.870
13
1.08596
SO
1.13599
t
1.04531
14
l.C'9286
21
1.14361
POTASSIUM.
FOTABSn PBRHANGANAS.
POTASSIUM SED KALIUM PEBMANQANICUM SEU
HYPERMA.NOANICUM.
Permanganatt of Potatrium. Potauiam Ptrmanganate.
Oer. UebennangansftUTeB Knlium ; Fr. Permanganate do polasse ;
8p. Permangftnato de piilaaa.
K,Mn,0,i 314.
Slender, dark-purple, prismatic crystals, belonging to the rhom-
bic system (Fig. 151), of a metallic lustre, permanent in the air, and
having a specific grftvity of 2.71 ; they docrepitate
when thrown upon burning coals, or when sud- Fm. 151,
denly hcitted, and when mixed with Bulphur or
phoaphoruB, a mixture is obtained which takes
fire or explodes violently on percussion or by
heating; on exposure to a red lieat, the salt
gives off oxygen, and leaves a black residue of an
alkaline reaction.
Potassium permanganate is soluble, with the ex-
ception of a slight bn>wn residue, in 20 parts of
water at 15° C, (o9^ P".), and in 3 parts of boiling
water; it is insoluble in alcohol, and is slowly de-
composed in contact therewith. Its concentrated
solution has a deep violet-red color, when highly
diluted, a rose color, a sweet, astringent taste, is
neutral, and becomes yellowish-brown when mixed
and heated with alcohol.
Since permanganic acid is readily reduced, the
solution of the salt is decomposed and decolorized
by most organic substances, and by inorganic reducing agents —
e. 'J., sulpbnrous and oxalic acids, hydrogen sulphide, and all
metallic aubsalls. Potassium permanganate is, therefore, a pow-
erful oxidizer, causing more or less violent reactions with many
substances, and the combustion of inflammable bodies.
Ezamlnatiim :
The purity of the salt may readily be determined by the fol-
lowing simple test; 0.314 gram of the potassium permanganate
is dissolved in wajer to the measure of one liter; another solution
is then prepared by dissolving 0.63 gram of pure, crystallized
oxalic acid in water, acidulated with sulphuric acid, to the measure
of a liter ; if tiie potas.sium permanganate is pure, one cubic centi-
meter of the above jiermauganate solution will require for com-
plete decoloration an equal volume, or exactly one cubic centimeter
of the oxalic acid solution, and the amount of the latter, which is
required to produce this reaction, will be, therefore, in direct pro-
portion to the purity of the salt.
4{)S MAVUAL or CHEMICAL ANALTSIB.
Nilra(e and ChlnriiJe. — A portion of the decolorized liquid, as
obtained by the preceding test, ia carefully poured upon a cold
solution of ferrous sutpbnte in strong sulpburia acid, when a dark-
colored zone at the line of contact of the two liquids will indicate
the presence of m'trutt .■ another portion of the decolorized liquid
ie tested with a few drops of a solution of argentic chloride, wnen
a pernianenl white turb.dity or precipitate will reveal the presence
of chlurt'ile.
Sulph'ite may be delected bv boiling an aqueous solution of llie
Fait with an excess of ammonia- water, until all the manganese i.i
precipitated as bydrated ox de; the liquid is then filtered, nnd
the colorless filtrate subsequently tested with barium chloride,
when an ensuing white precipitate will reveal the presence of
sulphate.
The United Stales Pharmacopoeia directs that if 0.786 gram of
the salt be dissolved in 50 cubic centimeters of boibng, distilled
water, and 5 cubic centimeters of sulphuric acid be cautiously
added, the solution so formed should require for complete decolora-
tioti not less than 24.7 uubic centimeters of the volumetric solu-
tion of oxalic acid (corresponding lost least 98.8 percent, of pure
potassium permanganate).
EF0TA8BII eVVPBAa.
POTASSIUM BBC KALIUM SUI.FUItlCUM.
Sulphale of PoUuiium. Polonium Sutpkatt.
On. Bclivefeluiirea Ealiuin ; Fr. Siiirme de potMse ; Sp. Suliilo de
K.SO,; 174.
0
;
Hard, colorless, transparent, sh.ort, six-sided prisms, or pyra-
mids, belonging to the rhombic system (Fig. 152), or a while,
granular powder, anhydrous, and permanent
Fio. 13!. in the air, ;ind having a spec, grav. of 2.(i48;
when beatcd, the crysinlf decrepitate strongly,
and at a strong, red heat iliey fuse, without de-
composition, solidifying again on cooling to a
crystalline mass; at a white beat, thoy are to
a slight extent volatilized. The salt, when
heated on the looped end of a platinum -wire,
imparts a violet color to the non-luminous
Hume.
Potassium sulphate is soluble in Q parts of
water at 15" C. (59° F.), in 4 parts of boiling
water, sparingly soluble in glycerin, and in-
soluble in strong alcohol, nnd solution of poias-
flium hydrate of the spec. grav. 1.35. Its aqueous solution Las a
iline bitter taste, is neutral, and forms white precipitates with
POTASSIUM. 499
tartaric acid or sodium bitartrate, and with solutions of salts of
calcium, barium, or lead.
Exandnation :
Potassium lisnlphate will be indicated by an acid reaction of
the solution of the salt, and also by the loss of weight, when the
salt, previously dried at 110^ C. (230° F.), is heated nearly to
redness in a covered porcelain crucible.
Sodium sulphate is indicated by the property of imparting a
persistent yellow color to the non-luminous flame, and by a greater
degree of solubility in cold water than that above stated ; one
part of the powdered salt, when dissolved in eight parts of boil-
ing water, must, on cooling, give a crystalline deposit ; otherwise
sodium sulphate, or an admixture of more soluble salts, is indi-
cated; in this case the solution may be tested with potassium
metantimoniatc for sodium, and, in another portion, after dilution
with water and acidulation with nitric acid, by jneans of argentic
nitrate for chloride. Nitrate will be detected in the aqueous solu-
tion of the salt, after the addition of a drop of indigo solution and
a little concentrated sulphuric acid, by decoloration of the liquid
upon heating.
Calcium and Mafjnesium Salts.— The aqueous solution of the
salt is tested with ammonium oxalate, when a white precipitate
will reveal the presence of calcium; after the removal of the
latter, if present, by filtration, solution of ammonium chloride,
ammonia-water, and sodium phosphate are added, when the forma-
tion of a white, crystalline precipitate will reveal the presence of
magnesium.
Metallic impurities are detected in the warm aqueous solution,
after acidulation with hydrochloric acid, by a dark coloration or
turbidity upon saturation with hydrogen sulphide, or, after filtra-
tion, if necessary, and neutralization with ammonia-water, by the
addition of ammonium sulphi*de. Potassium ferrocyanide should
cause neither a blue {iron) nor a reddish (cojo/^er) coloration in the
slightly acidulated solution.
POTA88II SULPHIS.
POTASSIUM SEU KALIUM SULFUROSUM.
Sulphite of Potassium, Potassium Sulphite,
Ger. Schwefligsaures Ealium ; Fr. Sulfite de potasse ; 8p. Sulfite de potass.
KSO3 + 2H3O; 194.
Colorless, opaque, obliquely rhombic, octohedral crystals, or a
white, crystalline powder, odorless, and somewhat deliquescent on
exposure to a moist atmosphere ; it contains two molecules (18.55
J 00
MANUAL OF CHBMII
per cent.) of water of eryatallizatioii, which are Jost by drying at
a moderate heat: al a red heat it is decomposed, leaving an alka-
1 ne residue consisting of potassium sulphate, sulphide, and uxidc,
which imparls a brown color to inoistened turmeric paper, and,
on the addition of an auid, develops the odor of hyarugeu sul-
phide.
PdtHssium sulphite is soluble in 4 parts of water al 15° C.
(59° F), and in 6 parts of boiling water, but is very sparingly
I'olubte in aleoho!. The aqueous solution possesses a bitter, saline,
and hulphurouH taste, a slightly alkaline reaction, and yields a
while cryatalliuo precipitnle on the addition of a coti«%ntrated
solution of sodium bilartratc; with argciitie nitrate it yields a
white precipitate, which beeomeM blackened on heating. Oil the
oddition of dilute liydrouhloric or sulphuric acid to the solution
of the salt, sulphur dioxide ia libernlea, which may be recognized
by the odor of burning sulphur, but no turbidity is thereby pro-
duced in the liquid (disiiuction from hyposulphite).
Examination :
f>ul}ihii(e may be detected in the dilute sulut'on of the salt,
strongly acidulated with hydrochloric acid, by a white precipitate
on the addition of barium chloride.
Estimation:
About 0,3 gram of the salt is dissolved in 25 cubic centimeters
of water, in a beaker, a little mucihige of starch added, and sub-
seqiiently a decinormal solution of iodine (page 93) allowed lo
flow into the liquid from a burette until, with couaiant stirring, a
permanent blue coloration of the liquid is just produced. Tlie
number of cubic cenlimclers of iodine solulioo required lo pro-
duce this reaction, when multiplied by the decimal 0.0097, will
represent the amount of pure, crystallized potassium sulphite,
K^O, +211,0, in the quauliiy employed, and therefrom iu per-
ceiitage purity may readily be ealculaied.
The United Stales PharmaeopoBia directs that if 0.185 gram of
the palt be diasulved in 25 cubic centimeters of water, and a little
gelatinized starch added, at least 45 cubic centimeters of the
volumetric solution of iod.ne should be required, until a per-
manent blue lint apiiears after stirring (corresponding to at least
HO per cent, of pure potassium sulphite).
This hook is the pro :u
COOPER MEDICAL COU.,^.
5AN FRANCISCO. OAU
POTASSIUM. 501
POTASSII TARTRAS.
POTASSIUM 8EU KALIUM TARTARICUM.
Tartrate of Potamum. Potassium Tartrate,
Ger. Weinsaures Kalium ; Fr. Tartrate de potasse ; Sp. Tartrate de potasa.
CH(OH)-CO-OK
Colorless, semi-transparent, irregular, six-sided prisms, with
dihedral summits, belonging to the monoclinic system, or a white,
granular powder, of the specific gravity 1.96, and slightly deli-
quescent on exposure to a moist atmosphere. The salt contains
one-half molecule (8.83 per cent.) of water of crystallization;
when moderately heated, it mjlts, and, at a higher temperature,
becomes charred and decomposed, with the evolution of empy-
reumatic vapors having the odor of burnt sugar ; when strongly
ignited at a red heat, it leaves a blackened alkaline residue, con-,
sisting of a mi.xture of carbon and potassium carbonate, which
effervesces with acids, and imparts a violet color to the non-lumi-
nous flame.
Potassium tartrate is soluble in 0.7 part of water at 15'^ C. (59°
F.), and in 0.5 part of boiling water, yielding a neutral solution,
of a mild saline taste; it is but sparingly soluble in alcohol; its
aqueous solution is decomposed by most acids and acidulous salts,
forming, if not too dilute, a white, granular deposit of bitartrate,
and yields with argentic nitrate a white precipitate, which be-
comes blackened on heating; the concentrated solution also pro-
duces with calcium, barium, and lead salts, white precipitates,
which are soluble in dilute nitric acid.
Examination :
Potassium and Sodium Tartrate, — Oiie part of the salt when
shaken with an equal we ght of water must aft'ord a clear and
complete solution; an incomplete solution may ind cate an ad-
mixture of Rochelle salt. Such an admixture will also be indi-
cated by a greater loss of weight on drying the salt at 100° C.
(212° F.), pure Rochelle salt losing at this temperature 19.1 per
cent, of its weight; and may be further ascertained by reducing
a portion of the potassium tartrate, by ignition in a porcelain
crucible, to carbonate, and then testing the res due in the woa-
luminous flame, when a persistent bright-yellow color will reveal
the presence of sodium ; the filtered solution of the residue may
afterwards be tested by mixing it with an equal volume of solu-
tion of potassium metantimoniate; the occurrence of a white,
crystalline deposit, at once or after seVeral hours' standing, would
indicate an adulteration with potassium and^s'odium tartrate.
Bicarbonate^ carbonate^ and bitartrate ^slto recognized in the solu-
502 UADUAL OF OUKMTCAL AKALYSTB.
lion of llio sail, llie two former by efferveaceoce on llie nddition
of an auid, and by an alkaline rcautiua upon turmeriu-paper; ibe
latter by its relatively Bpariiiy solubility in cold water, and by
an acid reaotioo upon blue litinus-paper.
Ammonium galls will be recognized by the development of the
odor of ammonia, when a portion of the salt ia.hcated, in a test-
tube, with H strong solution of potaiisium or sodium hydrate, and
by the development of white fumes, when a glass rod, moistened
with acetio aoid, is held over the mouth of the tube.
Calcinm salla will be indicated in the solution by a white pre-
cipitate on the addition of solution of ammonium oxalate.
Sulphate and chloTtde may be detected in the dilute solution of
tlie khH, when it is slightly aeidulnted with diluted nitric acid,
and then tested, in separate portions, with argeniio nitrate for
ehloride, and with barium nitrate for sulphate.
Metallic impurities are recogniued in the ouneentrated solution
of the sail, after acidulation with hydrochloric acid and subse-
quent filtration, by & dark coloration or turbidity upon saturation
with hydrogen sulphide; or, after filtration, if necessary, by sub-
sequent neutralization with ammouii^water, and the addition of
ammonium sulphide.
Estimation:
2.938 grams of the salt are igniled in a porcelain cruciblu, at a
red heat, until ga.ses cease to be evolved ; the alkaline residue is
then extracted with warm water, the solution filtered into a
beaker, a few drops of litmus solution added, and titrated, with
the aid of a gentle heat, with a standard solution of oxalic or sul-
phuric acid (page 82), as described under potassium carbonate,
on pnge 474. The number of cubic centimeters of normal aciti
Holution which is thus required for the exact neutralization of
the liquid, when multiplied by 4, will indicate, without further
calculation, the percentage purity of thfe salt. By the employ-
ment of other quantities of the salt than precisely that above
stated, the calculation may also readily be made, with the oonaid-
eration that one cubic centimeter of the normal acid solution cor-
responds to 0.117 gram of pure crystallized potassium tartrate.
QniKIDIlTA.
CUINIDrNUM BEU CONCHININUM.
Quinidint, Qaiiiidi'ii, or ConQulnia.
Ger. ChiDiaia (ConclilDiD) ; Fr. Qaluidlne ; 8p, Qulnl^n*.
C„H,.N,0,+ 211,0; 360.
Large, colorless, shining, four-sided prisms, containing 2 mole-
cules (10 per cent.) of water of crystallization, and poattcusing a
QUINIDENA. 503
very bitter taste and a slightly alkaline reaction ; when heated
to 120^ C. (248^ F.), they lose their water of crystallization, and,
when thus deprived of water, melt at 16S° C. (334:.4° F.), to a
colorless liquid, which solidifies in a crystalline form upon cool-
ing ; at a higher temperature they are decomposed, and when
strongly heated on platinum-foil, burn slowly away, leaving no
residue.
Quinidine is soluble in 2000 parts of water at 15° C. (59° F.),
and in 750 parts of boiling water, in 26 parts of alcohol, and 22
parts of ether at 20° C. (6S° F.), and is also soluble in chloroform,
carbon bisulphide, and benzol ; it is freely soluble in water acidu-
lated with sulphuric acid, and the solution displays a blue
fluorescence. It neutralizes the acids, with the formation of
neutral and acid salts, which are mostly well crystallizable.
When exactly neutralized with diluted sulphuric acid, quinidine
yields a solution which affords the same reactions as quinidine
sulphate, and should respond to the tests for quality and purity,
as described under the latter, on pages 503-504.
QUINIDIN2I SULPHAS.
CHINIDINUM SEU CONCHININUM 8ULFURICUM.
Sulphate of Quinidine^ Quinidiay or Conquinia, Quinidine Sulphate,
Qer. ScUwefelsaures Chinidin ; Fr. Sulfate de quinidine ;
Sp. Sulfate de quinidina.
(C^H,,N,0,),H,SO, -h 2 11,0 ; 782.
White, silky, prismatic needles or tufts, permanent in the air,
and containing two molecules (4.6 per cent.) of water of crystalli-
zation, which are completely eliminated at 120^ C. (248° F.);
when strongly heated, they burn slowly away, leaving no residue.
Quinidine sulphate is soluble in 100 parts of water, and in 8
parts of alcohol at 15^ C. (59^ F.); in 7 parts of boiling water,
and very soluble in boiling alcohol; it is freely soluble in acidu-
lated water, and in 20 parts of chloroform at 15^ C. (59° F.), but
is almost insoluble in ether. The aqueous solution is neutral in
its action upon litmus, possesses an intensely bitter taste, and,
when acidulated with sulphuric acid, displays a blue fluorescence;
with barium chloride it yields a white precipitate, insoluble in
hydrochloric or nitric acid, and with chlorine water, followed by
the addition of ammonia- water in slight excess, an emerald-green
coloration is produced ; if the addition of ammonia- water be pre-
ceded by a few drops of a solution of potassium ferrocyanide, the
solution assumes a bright-red color. When to a solution of qui-
nidine sulphate ammonia-water is added, a white precipitate of
504 MASUAL OP CHBMICAL AHALT8I8.
qainidine is produced, which is soluble in a considerable excess
of the reagent, and in about thirty times its weight of ether.
The neutral aqueous s^^lution of quinidine sulphate yields upon
the addition of a concentrated solution of potaf^sium io^lide a white
granular precipitate of quinidine hydriodate, C^TI,^NjO^HI, which
is very sparingly soluble in water and in alcohol.
Eumination : "
Qninine, Cinchonine^ and Cinchonidine, — These asfsociate alka-
loids of quinidine may readily be detecteil by the following sim-
ple test : 0.5 gram of the quinidine sulphate, together with an
equal weight of neutral potassium ioJide, is agitated with 10
cuVjic centimeters of water at about 60® C. (14<)° F.), the mixture
allowed to cool, and stand for an hour, with frequent agitation,
and filtered; to the filtrate one or two drops of ammonia-water
are then adde<l, when not more than a slight turbidity should be
pnxluced: a decided precipitate would reveal the presence of an
undue proportion of the above-mentioned associate alkaloids.
In consequence of the previously existing confusion in the ap-
plication of names, quinidine sulphate is liable to be confounded
with the less valuable alkaloid cinchonidine. The admixture or
substitution of the latter should therefore be the subject of a
sr^ecial test. It may be detected by its sparing solubility in
chloroform, whereas quinidine sulphate is freely soluble in this
liquid, and also by the following test: 0.5 gram of the salt is
agitated for about half a minute with ^U cubic centimeters of
water at 15° C. OV.r- F.), and immediately filtered: to the filtrate
two or three cubic centimeters c>f a saturated solution of }>otas-
siurn and sodium tartrate (Kochellc salt) are added, when, if an}'
considerable proportion of cinchonidine be present, a white, gran-
ular f>rccipiiate of cinchonidine tartrate, (C,gTI„NjO)jC^IIjO^, will
gradually be formed.
FoTHujn AlkdloidsoT Neutral Prhidphs. — An accidental admix-
ture or substitution of foreign alkaloids, such as morphine, bru-
cinc. etc., or of neutral principles, such as salicin, may in most
instances be detected by a coloration with concentrated sulphuric
or nitric acid, whereas pure quinidine sulj)liate dissolves without
color, or with the pnxJuction of but a faint yellowish tint.
Inorfjdnic im/turities may be detected by a non- volatile residue
when a little of the salt is ignited upon platinum-foil; or by
an insoluble residue, when 0.5 gram of the salt is dissolved in a
mixture of o cubic centimeters of chloroform and 2 cubic centi-
meters of absolute alcohol.
QUININA. 505
QUININA.
CHININUM. CHINIUM.
Quinine. Quinia,
Ger. Chinin; Fr. Qainine ; Sp. Quinina.
C^H,,N,0, + 3n,0; 378.
A snow-white, flaky, indistinctly crystalline powder, or minute,
needle-like crystals, containing 3 molecules (14.28 per cent.) of
water of crystallization, efflorescent on exposure to the air, and
possessing an alkaline reaction. It melts at 57° C. (134.6° P\),
and on the water- bath retains about 5.25 per cent, (about 1 mole-
cule) of water of crystallization, which is completely expelled at
125° C. (257° F.); the anhydrous alkaloid then melts at 177° C.
(350.6° F.), dissolves in hot water without previously fusing, and,
on cooling, separates in needles; while the alkaloid, containing
water of crystallization, first fuses in boiling water, and, on cool-
ing, does not crystallize. When strongly heated on platinum-
foil, it becomes cLarred and decomposed, and is finally completely
dissipated.
Quinine is soluble in about 1600 parts of water at 15° C. (59°
F.), in 700 parts of boiling water, in 6 parts of cold, or 2 parts
of boiling, alcohol, in 22.7 parts of ether,* in about 5 parts of
chloroform, and in 200 parts of glycerin ; and is also soluble
in carbon bisulphide, benzol, benzin, and ammonia-water; its
solutions have a bitter taste, and a feebly alkaline reaction, and
neutralize acids, with the formation of crystallizable salts. Qui-
nine is freely soluble in diluted acids, forming solutions which
exhibit an azure-blue fluorescence, caused by a change of re-
frangibility of the invisible chemical rays ; this property is not
displayed, however, by its solution in hydrochloric, hydriodic, or
hydrobromic acids, and docs not appear in such solutions by the
subsequent addition of sulphuric acid; the fluorescence may like-
wise be made to disappear in solutions in which it has previously
been produced, by the addition of the above-named acids, as also
by solutions of chlorides, bromides, and iodides, with the excep-
tion of mercuric chloride and bromide. Concentrated sulphuric
and nitric acids dissolve quinine without color, or with the pro-
duction of but a slight yellowish tint.
Solutions of quinine and its salts are precipitated by the alka-
line hydrates, carbonates, and bicarbonates, by calcium hydrate,
♦ The solubility of quinine in ether differs according to the form of the alka-
loid: requiring less wlien in the anhydrous or amorphous condition, as when
freshly precipitated from its solution in acidulated water by ammonia-water, and
jiirectly shaken with ether, tliau in the crystalline or hydrated form, which it
assumes when the precipitate is allowed to stand for several hours, previous to
the addition of the ether.
506 MASUAL OF CHEMICAL AHALT8IS.
by taniiic aod picric aci«l<, bv p-jtassium ferro^yanide. pota«y5:o-
mereuric i^xiide, i^>din);ced p»i»tas.siuin ioiide. and masi a'.ka'ioidal
reajrcrjts; the j-recipitates with calcium, i:H»ta>>iurn, and Svxiiam
hvdrat^*. and ammouia-waler, are redissolved bv a laree excess
of t}i<; [♦recipitant.
S-^'iiiti'in?; of quinine and its sails, when mixed with ch.orine-
water. and afterward? with an excess of water of ammonia, assume
a bri^'ht emerald-green color (thalleiochin i ; the green color passes
into red uj^/n the subsequent addition of jMitassium fern»cyanide ;
this characteristic reaction is most strikingly exhibited when, to
the s<»lution of quinine in chlorine-water, the solution of potassium
ferrrxryanide is first added, and subsequently the am m«»nia- water.
Wlien a solution of quinine or its salts in aeidu^.ated water is
precipitated with ammonia- water, and the turbid mixture is then
dividtr'd into three portions in as many test-tubes, and these shaken
severally with a little ether, chloroform, and l>enzol, tlie precipi-
tate will be dissolved, and tiie liquids subside into two clear, col-
orless strata in each test-lub»e.
Examination:
The identitv of quinine mav be conclusivelv established bv the
above described physical characters, and its l)ehavior towards re-
agents and sr)lvents ; it is also distinguished from many other alka-
loids and crvstallizable neutral principles, by affording no special
coloration in contact with cold concentrated sulpliuricor nitric acid.
Qiiiiudin*:, diichouhie, and ^'iucltonidtne. — 1 gram of the quinine
is triturated in a mortar with U.o gram of ammoniiim sulphate
and o cubic centimeters of distilled water, and the mixture thor-
oughly dried on the water-bath : the residue (which should he
neutral to lest-paj»er> is agitated with 10 cubic centimeters of dis-
tilled water, this mixture macerated at lo" C. (51i- F.) for half an
hour, tiien filtered, and to o cubic centimeters of the filtrate, in a
test tub*.'. 7 cubic centimeters of ammonia- water, spec. grav. O.MO,
are added, without shaking ; on gently turning the test-tube, tiiere
shouM l>e formed, either at once, or after a short time, a clear liquid ;
an ensuing permanent precipitate would indicate an admixture of
more than about 1 per cent, of cinchonidine and quinidine. and of
more tiiau traces of cinchonine. If the temperature during mace-
ration was 10^ C. (00.>5° v.), 7.5 cubic centimeters of ammonia-
water may be added, and if 17' C. (02.0- ¥.), 8 cubic centimeters
mav be emi^loved.
• • •
Jnorffnuic irnjturitifs may readily Ix? detected by a non-volatile
residue, wIkmi a small portion of the quinine is strongly heated on
platinuni-tbil.
When <lissolve<l in dilute sulj>huric acid, quinine should respond
to the tests of purity for (quinine sulphate, as described under the
latter, on pages 521-523.
quiNiNA. 507
Estimation of the Alkaloids in Cinohona-Barks :
The therapeutical value of the cinchona-barks ia due to the alka-
loids contained in the bark, of which the principal ones are qui-
nine, quinidine, cittchonine, and dnchonidiiie. The estimation of
the commercial value, therefore, depends upon the determination
of the quantity of these alkaloids, and in particular of the first
one, in a known weight of the bark. Of the numerous methods
employed for this purpose, the following ones are simple, expe-
ditious, and reliable:
I. Fliiokiger'B Process :
From a large number of pieces of the bark, small fragment"! are
cut and reduced to a fine powder, so as to represent as nearly as
possible an average specimen of the bark to be examined ; 20
grama of the powder, contained in a porcelain capsule, are moist-
ened with ammonia-water, and, after standing for an hour, mixed
with SOsramsof hot water; it is then allowed to cool, subsequently
intimately mixed with milkoflime(prepared bv triturating 5 grams
of dry caustic lime with 50 grams of water), and the mixture evapo-
rated upon the water-bath until it is uniformly converted into
small, somewhat moist, crumb-like particles. This is
then transferred to a cylindrical glass tube (Fig. lo3), F'o- ^^■
which at .4 is 2.5 centimeters (1 inch) wide, and
from A to 5 16 centimeters (6.4 inches) long. At B
A small brass sieve is inserted, upon which a disk of
filtering pajier is secured by means of a bunch of
l<H>se cotton. The powder having been quite com-
pactly adjusted upon the cotton, it is again covered
at A, as in B, with a little cotton ; the latter having
been previously employed for removing the last
traces of the powdered bark from the capsule. At
JC. a tightly fitting cork is inserted, which is pene-
trated by the tube R, and connected with an inverted
small glass condenser. The lower end of the appa-
ratus, C, is tightly connected by means of a cork
with the flask A", containing about 100 cubic centi-
meters of ether. The flask is then heated by means
of a constant water-bath ; and in the same degree as
the vapors of ether are expelled through I), they
become again condensed in the condenser, drop
through the tube flupon the powder at A, penetrate
the entire column of powder A B, and flow at C,
saturated with alkaloid, into the flask K. To effect / ^ \
the complete exhaustion of the bark by the etlier. / 1«
the operation of displacement should lie continued ^- — -^
for nearly a day, but when once in progress it requires
but little attention. In order to determine whether the bark is
completely exhausted, a few drops of the ether, falling at C, are
collected in a small test-tube, and tested with putassio-meruuric
508 MANUAL OF CHEMICAL ANALYSIS.
icKlide; which should afford no turbidity if the process of extrac-
tion lias been suffieientlv loner continued. When this is accom-
plished, 'M) cuV)ic centimeters of one-tenth normal h\'drochloric
acid (HJti'} grams IICl in 1 liter) are added to the ether in the flask
JC, the ether distilled off, and subsequently so much hydrochloric
acid added as may be required to impart to the liquid an acid
reaction. The liquid is tlien filtered from the separated mixture
of fat, chinovin, and chlorophyll, and, after having become
thoroughly cooled, 40 cubic centimeters of one-tenth normal
wxlium hydrate solution (4 grams XaOH in 1 liter) are added,
and the whole allowed to repose until the precipitate has sub-
sided, and the supernatant liquid has become perfectly clear.
Sfxlium hydrate is then gradually added to the liquid as long
as a precipitate continues to be j>roduced, for which purpose
a solution of the spec. grav. 1.3 is the most serviceable. The
precipitated alkaloids are afterwards collected on a filter, and
gradually washed with a little cold water until a few drops of the
washings, when allowed to flow on the surface of a cold, saturated,
neutral, aqueous solution of quinine sulphate, cease to produce a
turbidity. The drained precipitate, contained on the filter, is then
gently pressed between bibulous paper, and dried by exposure to
tlie air; it may afterwards readily be removed from the paper
without loss, and, after thoroughly drying upon a watch-glass
over sulphuric acid, is finally dried at 100^ C. ^212° F.), and
wcighc(l ; tlic weight of the precipitate, multiplied oy 5, will give
th(; total p(irc('iitag(i of mixed alkaloids in the bark. If it be de-
sired to establish the presence of quinine in the precipitate, a
small portion of it may be dissolved in acidulated water, and sub-
secpuMitly tested with chlorine- water and ammonia, as described
on page oOd.
Separation of the Alkahuls,
When the se))aration and quantitative estimation of the re-
spective alkaloids are required, the following method of De Vrij
may be eniploved. The powdered mixed alkaloids are treated
with ten times their weiglit of ether, and. after agitation, left at
rest till tlu* next day. By this operation the alkaloids are sepa-
rated into two parts, viz., one (A) soluble in ether, and another
(B) insoluble in that liquid. The part soluble in ether contains
the quinine and the amorphous alkaloid, together with traces of
(piinidine, while the insoluble part cr)ntains the cinchonine, cin-
ehonidine, and quinidine. These two parts are separated by
liltration, the insoluble portion washed with a little ether, and the
ethereal solution either directly evaporated, or the ether recov-
ered bv distillation.
*
A, Part Sithihle in Ether, — The ether having been evaporated,
and the residue dried at 100° C. (^212- F.), this may in many
QUININA. 509
cases be practically considered a« consisting simply of quinine.
IC however, the estimation of the quinidine and amorphous alka-
loid is required, the residue is dissolved in sufficient acetic acid
to afford a neutral solution, and an alcoholic solution of potassium
iodide added, which will produce a sandy precipitate of quinidine
hydriodate,* CjoHj^N,0,.HI. One part of this hydriodate, when
dried at 100° C. (212° F.), represents 0.717 part of anhydrous qui-
nidine. To the warmed filtrate from the latter precipitate ammo-
nia-water is added until it ceases to produce a precipitate ; the
mixture is then shaken at once with ether, the ethereal solution
allowed to evaporate, and the residue dried at 100° C. (212° F.).
This residue will consist principally of quinine, accompanied pos-
sibly by amorphous alkaloid and quinamine. In order to exclude
the latter bases, which are always only present in very small
amount, the ethereal residue is dissolved in 10 parts of diluted
alcohol, spec. grav. 0.915, the solution exactly neutralized with
alcoholic sulphuric acid, and as much of the latter afterwards
added as was required for neutralization. To this solution an
alcoholic solution of iodine is carefully added until a precipitate
ceases to be formed. If a considerable amount of quinine is
present, there will appear immediately a black precipitate of
quinine iodo-sulphate or herapathite^ but if the amount of quinine
is only very small, it may happen that no precipitate will be
formed at once, and in the latter case only a small amount of
iodine should be added, and the liquid, after having been well
stirred with a glass rod, is left at rest till the next day. If qui-
nine is really present, it will then be precipitated in the form of
herapathite, which may be collected on a filter, washed with
strong alcohol, and first dried upon bibulous paper and afterwards
at 100° C. (212° F.). One part of the herapathite, when thus
dried, represents, in accordance with the formula (C,qHj^N,Oj)^ +
3HjS0^-f 2HI + 4I, 0.55 part of pure quinine.
To the liquid separated from the herapathite, a few drops of
sulphurous acid are added, whereby the iodo-sulphate of amor-
phous alkaloid is converted into hydriodate, and the reddish-
brown color of the solution disappears. The solution is then
carefully neutralized with sodium hydrate, heated on the water-
bath to expel the alcohol, and a solution of sodium hydrate in
slight excess subsequentlv added, by which the amorphous alka-
loid will be precipitated, including quinamine if present.
B. Part Insolnhle in Ether, — This is converted into neutral
acetate by the addition of a sufficient quantity of acetic acid, and
to the solution potassium and sodium tartrate (Rochelle salt) in
slight excess is subsequently added. After stirring with a glass
♦ If only traces of quinidine be present, ns is usimlly the case, no precipitate
wiU be formed; but simply \%'hitc striee on the surfaces of tbc glass which haTO
come in contact with the glass rod.
510 MANUAL OF CHEMICAL AKALTSIS.
rod, the solution is left at rest' for a day, when, if einchonidine is
present in appreciable quantity, its tartrate will }ye separated is a
crystalline form, while the other tartrates remain dissolved. The
einchonidine tartrate is collected on a filler, washed with a little
cold water, and, after first drying ujx>n bibulous paper, is
finally dried at IM*" C. (212° F.land weighed. One part of cio-
chonidine tartrate represents, in accordance with the formula
(G,on^,0),.C^H^Og, 0.796 part of pure einchonidine.
To the filtrate from the latter precipitate, a solution of poias-
sium ioilide is added, and the whole well stirred with a glass rod.
The quinidine will thus be precipitated as hydriodate. in the fi»rni
of a sandy crystalline powder : it is collected on a filter, washed
with a little cold water, and, after first drying on bibulous [^aj^r,
is finally dried at 100- C. (212*^ F.), and weighed. One part of
this hyd^riodate represents 0.717 part of pure anhydrous quinidine.
The filtrate from the quinidine hydriwlate is finally precipitated
with s(Klium hydrate, whereby the cinchonine is obtained: this
is collected on a filter.- washed with a little cold water, and, after
first drying l)etween bibulous paper, is finally drieii at l(Mj® C.
(212^ P.), and weigheil.
n. Squibb's ProoesB :
To 1.2.') grams (19.29 grains) of well-burnt lime, contained in a
10-centinieter (4inch) capsule, 30 cubic centimeters (1 fluidounce)
of hot water are added, and, when the lime is slaked, the mixture
is stirred, and r> grams (77.10 grains » of the powdered cinchona
are added, the mixture yerv ihorouirhlv stirren, and disrosteJ in a
warm place for a few hours, or oyer night. The mixture is then
dried at a low tem|erature on a water bath, rubbed to p<»wder in
the caj sale, and transferred to a tla>k of Ino cubic centimeters
(8.3 fluid* Minces) capacity, and 2o cubic centimeters iO."^ fluidounce)
of aniylic alcohol added. The tlask is afterward corked, and
digested in a water-bath at a boiling temperature and with fre-
quent, yigoroiis shaking for four hours. It is then allowed to
ccK^l, and ♦»*» cubic centimeters rj tl a idounces) of stronger ether,
spec. gray. 0.72\ added, and again shaken yig^rously and fre-
quently during an hour or more. The li<juiil is now filtereil
through a donV>l«* tilter of 10 centimeters (4 inches) diameter into
a flask of l.')U eubic centimeters (o tluidounces) capacity, and the
residue intnsferred to the tilter. Tiie flask is linsel and the
rinsii.'L's bn>ngljt i*u to the filter with a mixture of 10 yolumes of
amvlic alcol.-*! an«l 4o yolumes of stron«:er ether, and the residue
on the Alter j»erc«»Iate<l with 15 cubic centimeters \0.o fluidounce)
of the same mixture, added dr«.»p by drop from a pi{>eite to the
edges n\' the fi.ter an<l surface of the residue. The residue is
afterward returned to the flask from whence it came, 30 cubic
centimeters 1 1 fluidounce) of the amvlic alcohi^l and ether mix-
ture added, shaken vigorously for i\\K: minutes or more, and the
QUININA. 511
whole returned to the filter, and the residue again percolated with
15 cubic centimeters of the menstruum, applied drop by drop from
a pipette, as before. The filter and residue are now put aside in
order that it may be afterward tested in regard to the degree of
exhaustion.
The ether is now boiled off from the filtrate in the flask by
means of a water-bath, taking great care to avoid the ignition of
the ether vapor, and also to avoid explosive boiling, by having a
long wire in the flask. When boiled down as far as practicable
in the flask, the remainder is transferred to a tared capsule of 10
centimeters (4 inches) diameter, and the evaporation continued on
a water-bath until the contents are reduced to about 6 grams
(92 grains). This is transferred to a flask of 100 cubic centimeters
(3.3 fluidounces) capacity, rinsing the capsule with not more than
4 cubic centimeters (64 minims) of amvlic alcohol, and adding the
same to the contents of the flask. 6 cubic centimeters (96 minims)
of water and 4 cubic centimeters (64 minims) of normal solution
of oxalic acid are then added, and the mixture shaken vigor-
ously and frequently during half an hour. The mixture, while
intimately well mixed, is poured on to a well-wetted double filter
of 12 centimeters (4.75 inches) diameter, and the aqueous solution
filtered from the aniylic alcohol into a tared capsule of 10 cen-
timeters (4 inches) diameter. The filter and contents are washed
with 5 cubic centimeters (80 minims) of water, applied drop by
drop from a pipette to the edges of the filter and surface of the
amvlic alcohol. The amylic alcohol is then poured back into the
flask over the edge of the filter and funnel, rinsing the last por-
tion in with a few drops of water. 10 cubic centimeters (160
minims) of water and 1 cubic centimeter (16 minims) of normal
solution of oxalic acid are now added, again shaken vigorously
for a minute or two, and the whole returned to the wetted filter,
and the aqueous portion filtered ott* into the capsule with the first
portion. The amylic alcohol is again returned to the flask, and
the washings repeated with the same quantities of water and nor-
mal oxalic acid solution. When this has drained through, the
filter and contents are washed with 5 cubic centimeters (80
minims) of waU^r, applied drop by drop from a pipette. The total
filtrate in the capsule is evaporated on a water-bath, at a low tem-
perature, until it is reduced to about 15 grams (241 grains) and
this transferred to a flask of 100 cubic centimeters (3.8 fluidounces)
capacity, rinsing the capsule with 5 cubic centimeters (80 minims)
of water, and adding this to the contents of the flask. 20 cubic
centimeters (0.66 fluidounce) of purified chloroform are now first
added, and then 6.1 cubic centimeters (98 minims) of normal solu-
tion of sodium hydrate, and shaken vigorously for five minutes
or more. While still intimately mixed by the shaking, the mix-
ture is poured upon a filter of 12 centimeters (4.75 inches) diam-
eter, well wetted with water. When the aqueous solution has
512 MANUAL OF CHEMICAL ANALYSIS.
passed through, leaving the chloroform on the filter, the filter and
chloroform are washed with 5 cubic centimeters (80 minims) of
water, applied drop by dron. The chloroform solution is then,
by making a pin-hole in the point of the filter, transferred to
another filter of 10 cenlirnetors (4 inches) diameter, well wetted
with chloroform, and placed over a tared flask of 100 cubic cen-
timeters (3.8 fluidounces) capacity. The watery filter is washed
through into the chloroform-wet filter with 5 cubic centimeters
(80 minims) of purified chloroform, and, when this has passed
through into the flask, the chloroform-wet filter is also washed
with 5 cubic centimeters (80 minims) of chloroform, applied drop
by drop to the edges of the filter. When the whole chloroform
solution of alkaloids is collected in a flask, the chloroform is
boiled oft* to dryness in a water-bath, when the alkaloids will be
left in warty groups of radiating crystals, adhering over the bot-
tom and si^es of the flask. The flask is then placed on its side
in a drying-oven, and dried at 100° C. (212° F.) to a constant
weight. The weight of the contents, multiplied by 20, gives the
percentage of the total alkaloids of the cinchona in an anhydrous
condition, to within 0.1 or 0.2 per cent,, if the process has been
well managed.
Estimation of Quinine,
Into the flask containing the total alkaloids, after these have
been weighed, are placed o grams (78 grains) of glass, which has
been ground up in a mortar to a mixture of coarse and fine
powder, and 5 cubic centimeters (80 minims) of stronger ether
added. The flask is then corked, and shaken vigorously until,
by means of the glass, all the alkaloids have been detached from
the flask and ground up in the j^resence of the ether into fine
particles. In this way the definite quantity of ether which is
large enough to dissolve all the quinine that could possibly be
present, becomes entirely saturated with alkaloids in the propor-
tion of their solubility, and the solution will necessarily embrace
all the very soluble ones as the quinine.
Two test-tubes are now marked at the capacity of 10 cubic
centinaeters (1(30 minims each), and a funnel and filter of 7 centi-
meters (2.8 inehes) diameter placed over one of them. The filter
is well wetted with ether, and the mixture of alkaloids, ether,
and glass poured on to it from the flask. The flask is rinsed out
two or three times on to the filter with fresh ether, the filter then
washed, and the glass percolated with fresh ether, applied drop
by drop from a i)ipette, until the liquid in the test-tube reaches
the 10-cubic centimeter (160-minim) mark. The funnel is then
changed to the other test-tube, and the washing and percolation
with ether continued until the mark on the second test-tube is
QUININA. 51
o
reached by the filtrate. The contents of the two test-tubes are
poured into two small tared capsules, evaporated to a constant
weight, and weighed. The first capsule will contain what may
be called the ether-soluble alkaloids, and if from the weight of
these the weight of the residue in the second capsule be sub-
tracted, the remainder will be the approximate weight of the
quinine extracted from the 5 grams of bark. These weights,
multiplied by 20, will give the percentage of ether-soluble alka-
loids and of quinine.
m. Process of the United States PliarmacopcBia :
1. For Total Alkaloids.
Twenty grams of the cinchona, in very fine powder, and fully
dried at 100° C. (212° F.), are thoroughly mixed with 5 grams of
lime which has previously been made into a milk with 50
cubic centimeters of distilled water, and the mixture completely
dried at a temperature not above 80° C. (176° F.). The dried
mixture is digested with 200 cubic centimeters of alcohol, in a
flask, near the temperature of boiling, for one hour, and, when
cool, the mixture poured upon a filter of about 15 centimeters (6
inches) diameter. The flask is rinsed and the filter washed with
200 cubic centimeters of alcohol, used in several portions, and
allowing the filter to drain after the use of each portion. To the
filtered liquid enough diluted sulphuric acid is added to render
the liquid acid to test-paper, any resulting precipitate (calciuni
sulphate) allowed to subside, the liquid decanted, in portions,
upon a very small filter, and the residue and filter washed with
small portions of alcohol. The filtrate is then distilled or evapo-
rated to expel all the alcohol, allowed to cool, passed through a
small filter, and the latter washed with distilled water slightly
acidulated with diluted sulphuric acid, until the washings are no
longer made turbid by solution of sodium hydrate. To the fil-
tered liquid, concentrated to the volume of about 50 cubic centi-
meters, when nearly cool, enough solution of sodium hydrate is
added to render it strongly alkaline. The precipitate is col-
lected on a wetted filter^ allowed to drain, and washed with
small portions of distilled water (using as little as possible), until
the washings give but a slight turbidity with test solution of
barium chloride, and the filter drained by laying it upon blotting
or filter papers until it is nearly dry.
The precipitate is then carefully detached from the filter, and
transferred to a weighed capsule ; the filter is washed with dis-
tilled water acidulated with diluted sulphuric acid, the filtrate
made alkaline with solution of sodium hydrate, and, if a precipi-
tate results, this is washed on a very small filter, allowed to drain
well, and also transferred to the capsule. The contents of the
latter are now dried at 100° C. (212° F.) to a constant wxight,
33
514 MA5UAL OF CHRMICAL ANALYSIS.
cooled in a desiccator, and we:'ghed. The number of grams, mul-
tiplied by 5, equals the percentage of total alkaloids in the cin-
chona.
2. For Quinine.
To the total alkaloids from 20 grams of cinchona, previously
weighed, distilled water acidulated with diluted sulphuric acid is
added, until the mixture remains for 10 or 15 minutes after diges-
tion just distinctly acid to test-paper. It is then transferred to a
weighed beaker, rinsing with distilled water, and adding of this
enough to make the whole weigh 70 times the weight of the alka-
loids. Solution of sodium hyarate, previously well diluted with
distilled water, is now added, in drops, until the mixture is exactly
neutral to test-paper, digested at 60** C. (140® F.), for 5 minutes,
then cooled to 15° C. (59® F.), and maintained at this temperature
for half an hour. If crystals do not appear in the glass vessel,
the total alkaloids do not contain over 8 per cent, of their weight
of quinine (corresponding to 9 per cent, of crystallized sulphate
of quinine). If crystals appear in the mixture, the latter is passed
through a filter not larger than necessary, prepared by arying
two filter papers of 5 to 9 centimeters (2 to 3.5 inches) diameter,
trimming them to an equal weight, folding them separately, and
placing one within the other so as to make a plain filter four-fold
on each side. When the liquid has drained away, the filter and
contents are washed with distilled water of a temperature of 15®
C. (r)l»^ F.), added in small portions, until the entire filtered liquid
weighs 90 times the weight of the alkaloids taken. The filter is
tlien dried, without siiparating its folds, at 60® C. (140® F.), to a
constant weight, allowed to cool, and the inner filter and contents
weighed, taking the outer filter for a counter-weight. To the
weight of eflloresced quinine sulphate so obtained, 11.5 i>er cent,
of its amount is added (for water of crystallization^ and 0.12 per
cent, of the weight of the entire filtered liquid added (for solubility
of the crystals at 15° C, or 59° F.). The sum in grams, multiplied
by 5, equals 1 he percentage of crystallized quinine sulphate equiva-
lent to the quinine in the cinchona.
IV. Process of the Pharmacopoea Oermanioa :
Twenty grams of the finely powdered bark are repeatedly and
actively agitated with a mixture of 10 grams of ammonia-water,
spec. grav. 0.9f>0, 20 grams of alcohol, spec. grav. 0.S30 to 0.S34,
and 170 grains of ether, s{)ec. grav. 0.724 to 0.728, and, at^er
standing for a day, 120 grams of the liquid are poured offl After
♦he addition of 3 cubic centimeters of normal hydrochloric acid
^containing 6C\b grams HCl in 1 liter), the ether is removed by
distillation or evaporation, and, if necessary, so much hvdrochioric
acid added as is required to acidulate the solution.* This is then
* In consequence of the small amount of liquid obtained after the rvmoTal of
the alcohol and ether, Prof. Fliickiger suggests that the soluii jo be eTapormted
QUININA. 515
filtered, and the cooled liquid mixed with 3.5 cubic centimeters of
normal solution of potassium hydrate (page 87). After the alka-
loids have separated, solution of potassium hydrate is added to
the clear supernatant liquid, until no further precipitate is pro-
duced. The entire precipitate is finally collected upon a filter,
and gradually washed with a little water until the drops of liquid
escaping from the filter, when allowed to fall upon the surface of
a saturated neutral solution of quinine sulphate in cold water, no
longer produce a turbidity. After being allowed to drain, the
alkaloids are gently pressed between bibulous paper, then dried
by exposure to the air sufficiently to admit of bringing them into
a glass capsule, in which they are placed over sulphuric acid, and
finally completely dried in a water-bath.
QUININ^I H7DROBROMA8.
CHININUM 8EU CHINIUM HYDROBROMICUM 8EU
HYDROBROMATUM.
Hydrohromate of Quinine or Quinia, Quinine Hydrohr ornate,
Oer. BromwasscrstofllHiures Chinin ; Fr. Hydrobromate de quinine ;
Sp. Bromhidrato de quinina.
C«n„N,0,.HBr + 2H,0 ; 440.8.
Colorless, lustrous, prismatic, or needle-shaped crystals, con-
taining two molecules (8.16 per cent.) of water of crystallization;
they are permanent in ordinary air, but efflorescent in a warm
atmosphere; when exposed to a moderate heat the salt fuses,
and, when strongly heated, burns slowly away, leaving no residue.
Quinine hydrohromate is soluble in about 16 parts of water,
and in 3 parts of alcohol at 15° C. (59° F.); in 1 part of boiling
water, and in less than 1 part of boiling alcohol ; in 6 parts of
ether, in 12 parts of chloroform, and moderately soluble in glyce-
rine. The aqueous solution possesses a very bitter taste, is neu-
tral in its action upon litmus, and, when acidulated with sulphuric
acid, displays a blue fluorescence; if chlorine- water be added to
the solution, and subsequently ammonia-water in excess, a bright
emerald-green coloration is produced.
The aqueous solution of quinine hydrohromate, if not too dilute,
yields with ammonia-water a white precipitate of quinine, which
is readily dissolved by an excess of the precipitant, or when
to dryness, and the hydrochlorates of the alkaloids again taken up with 80 cubic
centimeters of warm water, or, preferably, to apply originally 80 cubic centi-
meters of decinormal hydrochloric acid, and by distilling on the alcohol and
ether to concentrate the liquid to 30 cubic centimeters In all cases the alcohol
and ether should be completely removed before the addition of the potassa
BoloUon.
6X6
AMt'AL OF CHEMICAL ANALYSIS.
mixed and agitated witli ctlier; with urgeutic nilrate it j'ields a
white precipitate of nrgentic bromide, which, when collected, nod
wnsbed wita a little water, is insoluble ia diluted nitric acid, or
in a solution of ammotiium carbonate.
Examination:
With rererence to its mode of pi^pnration, quinitie brdrobro-
m:iic should be examined for its possible contamination with qui-
nine sulphate, or with barium bromide, by acidulating its aqueous
solution with nitric acid, and subsequently testing, in ticp&rate
jiortions, with barium chloride for tLe former, and witli diluted
sulphuric acid for the latter. If either of these impurities are
found, it will, of course, exclude the presence of the other.
Walfr. — The presence of free water may be ascertained by tlie
determination of ihe loss of weight upon drying 1 gram of the
salt at the temperature of 100' C. (212^ F.) until its weight
remains constant. When dried at this temperature the residue
should weigh not leiiis than 0.918 grain, otherwise an undue per-
centage of water is indicated.
Qumidhif. Oinehonirx, and Cinchonidint. — One and oue-balf
grams of the salt are disst>lved in 15 uiibic centimeters of hot dis-
tilled water, the solution stirred with 0.6 gram of crystallized
sodium sulphate in powder, the mixture maintained at IS" C.
(5fl° F.) for half an hour, and then drained llirough a filter just
ftuflioiently large to contain it until 5 cubic centimeters of filtrate
are obtained. Upon proceeding further, a." directed under ^wi-
nififf, on page 506, the results there stated should be obtained.
The further examiiiation of quinine hydrobromate for other
foreign organic or inorganic substances or alkaloids ia the sRmc
aa described under Quininie i^iilphus, on pages 522, 523.
QUIMIHAI BISULFBAS.
Biit'lpluile of Qui
Ger. SnureB ScUwefclsatirps Cliimn; Fr. Buirnieactde de quinine;
Bp. BiBUlfitto de qulnina.
C„H„N,0,.H,S0.+7H,0; 54H.
Colorless, transparent, prismatic erystala, belonging to the rhom-
bic system, or small needles, efflorescent, and assuming an ojiaque
whiteness on exposure to the air. The salt contains 7 molecules
(22.99 per cent.) of water of crystallization, which are lost by
drying at 100° C. (212° F.); when thus deprived of water, and
healed in a small porcelain capsule, it melts at 135^ C. (275" F.),
B i_
QUININA. 617
and is converted into quinicine bisulphate; fit a higher tempera-
ture, it becomes yellow, then red, and is finally carbonized with
the evolution of reddish vapors ; when strongly heated on plati-
num-foil, it burns slowly away, leaving no residue.
Quinine bisulphate is soluble in about 10 parts of water and in
32 parts of alcohol at 15° C. (59^ F.), and very freely soluble in
boiling water and in boiling alcohol. Its aqueous solution pos-
sesses an intensely bitter taste and an acid reaction, and displays
a vivid blue fluorescence; with barium chloride it gives a white
precipitate, insoluble in hydrochloric acid, and with chlorine-
water followed by the addition of ammonia, a bright emerald-
green color is produced; when ammonia- water is added to the
solution, a precipitate is produced which is readily soluble in an
excess of the precipitant, as also when mixed and agitated with
ether.
If to a solution of 1 part of quinine bisulphate in 20 parts of
acetic acid and 5 parts of alcohol, a few drops of a saturated alco-
holic solution of iodine are added, a precipitate of quinine iodo-
sulphate, (C^H^NPj^-f 3H,S0^-f 2HI-f 41, or herapathite, will be
produced ; this compound forms thin laminar crystals or groups
of stellate needles, of a bright green color and metallic lustre, and
is very sparingly soluble in water and in alcohol.
ExfunmatioQ :
Water. — The presence of free water may be ascertained by the
determination of the loss of weight upon drying 1 gram of the
salt at the temperature of 100° C. (212° F.) until its weight re-
mains constant. When dried at this temperature, the residue of
anhydrous quinine bisulphate so obtained should weigh not less
than 0.77 gram, otherwise an undue percentage of water is indi-
cated.
Quinidine, Cinchonine^ and Cinchonidlne, — One gram of quinine
bisulphate, previously dried at 100° C. (212° F.), is agitated with
8 cubic centimeters of distilled water, the mixture made exactly
neutral to test-paper by the cautious addition of ammonia-water,
and the volume of liquid increased to the measure of 10 cubic
centimeters by the addition of distilled water. The mixture is
then macerated at 15° C. (59° F.) for half an hour, when, upon
proceeding further as directed under Quinina, on page 506, the
results there stated should be obtained.
The further examination of quinine bisulphate for other foreign
organic or inorganic substances or alkaloids is the same as de-
scribed under Quininte Sulphas^ on pages 522, 523.
ANUAL OF CHEMIC
QUININJB HTDROCHI.ORA8.
QUINI^ MCRIAS. CHININUM 9EU CHINIUH HYDROCHLORICGM
8EU HYDROCHLORATUM
Hydroehhrate af Qui
r Quiaia. Quinine Hj/droekloraU.
C^H„N,0,.HC! + 2H,0; 896.4.
White, silky needles, or a cryetalline powder, coniaiiiing two
molecules (9.08 per cent.) of water of cryslallization ; it is perma-
nent at ordinary temperatures, but sHghtlv efflorescent in a warm
atmosphere; w'hen heated to from 100 to'UO'^ C. (212 U> 230" F.)
it loses its water of crystallizution, fuses at a higher temperature,
and, when strnngly heated on platiuum-foil, burns slowly avtiy,
leaving no residue.
Quinine hydrochlorate is soluble in 34 parts of water and in 3
parts of alcohol at 15° C. {59^ F.) ; in 1 part of boiling water, and
very soluble in boiling alcohol; and also soluble in 9 parts of
clili)roform, in tlie latter instance accompanied by the separation
of water; if, however, the salt be previously rendered anhydrous
by gently heating, it requires but its own weight of chloroform
for solution. The salt is also freely soluble in acidulated water,
and in diluted as well as in concentrated acids, without change of
color ; its aqueous solution is neutral, possesses a bitter taste, and,
when sufficiently diluted, displays a slight blue fluorescence on
the addition of dilute sulphuric acid; with chlorine -water, fol-
lowed by the addition of ammonia- water in excess, it aQbrda ft
bright emerald green coloration, and if the ammonia-water is
preceded by the addition of a few drops of a solution of potas-
sium ferrocyanide, a red color is produced; the aqueous solution,
acidulated with nitric acid, yields a white, curdy precipitate with
argentic nitrate, soluble in an excess of ammonia- water, and a
wliite precipitate with ammonia-water, which, however, is dis-
solved by ether, alcohol, chloroform, or benzol, when added and
agitated with the liquid.
Examlnatloa :
Water. — The presence of free water may be ascertained by the
determination of the loss of weight upon drying 1 gram of the
salt at the temperature of 100^ C. (212" F.) until its weight re-
mains constant. When dried at this temperature, the residue
should weigh not less than 0.91 gram, otherwise an undue per-
centage of water is indicated.
Quinidrnf, Vinchonine, and Clnchrynidine. — These associate alka*
loids of quinine may readily be detected by fffsse'a test, as de-
scribed under Qutninw •Sntp/ias, on page 521. In the application
of the test, 0.5 gram of quinine hydrochlorate and 0.25 gram of
QUININA. 519
crystallized sodium sulphate are added to 10 cubic centimeters of
water at 50-60° C. (122-140° F.), contained in a test-tube; the
mixture is well shaken several times, and, after standing for ten
minutes, 5 cubic centimeters of the clear filtered solution are
introduced into a graduated tube (Fig. 154, page 521), 1 cubic
centimeter of ether is added, and subsequently 5 drops of ammo-
nia-water, spec. grav. 0.960. The tube is now closed with a cork,
is agitated gently, and allowed to stand for several hours. If the
ethereal layer is now examined with a lens, it should show no
evidence of crystals ; the separation of crystals being evidence of
the presence of more than traces of the above-mentioned associate
alkaloids.
The detection of an admixture of the above-mentioned alka-
loids may also be accomplished by the following method : 0.3
gram of the quinine hydrochlorate is agitated with 6 cubic centi-
meters of distilled water, the mixture macerated at 15° C. (59°
F.) for half an hour, and filtered ; 4 cubic centimeters of the fil-
trate are then diluted with 100 cubic centimeters of distilled
water, and of the diluted solution 5 cubic centimeters are taken
in a test-tube, and 7 cubic centimeters of ammonia-water, spec,
grav. 0.960, added, without shaking; on gently turning the tube,
closed by the finger, there should be formed, either at once, or
after a short time, a clear liquid; an ensuing turbidity would
indicate an admixture with the above-mentioned associate alka-
loids of quinine.
In consequence of the occasional occurrence of an accidental
admixture or substitution of morphine hydrochlorate, the latter
salt may also be tested for. It may readily be detected in the
aqueous solution of the salt, by agitating it with a few drops of a
solution of iodic acid, when, if morphine be present, iodine will
be liberated, and upon subsequent agitation with a few drops of
chloroform or carbon bisulphide, the characteristic violet color
will be imparted to these liquids. The same reducing action may
also be shown, by adding to the solution of the salt a few drops
of a solution of potassium ferricyanide and ferric chloride, and
subsequently hydrochloric acid in slight excess, when, in the pre-
sence of morphine, a deep-blue coloration or precipitate will be
produced.
The presence of morphine, as also of many other foreign alka-
loids or neutral principles, will likewise be indicated by a red or
dark coloration in contact with concentrated nitric or sulphuric
acid, whereas pure quinine hydrochlorate affords no coloration,
or but a pale yellowish tint is produced.
With reference to the method of its preparation, its aqueous
solution needs, moreover, to be examined for contamination with
quinine sulphate or with barium chloride, by acidulation with
nitric acid, and subsequent testing, in separate portions, with
barium nitrate for the former, and with diluted sulphuric acid
Km, mOcj, iG^j Aemifafe. Bow-whste
■■fi«g oae iBalWr, or grovped in «nH. star-tike tafts ; tbe cry*-
tab *■»'■'■ ■era Bofacalea (14.15 p^ acot.) of vacer of cf7»l-
EartioB, ll«a of vkidi (camapoading }p 9i& par «at.) are lott
tf Umf txpimmrt u> a vans aad 6iy atmaaphere, or OMt* nm£iy
eof aO to tty*C.(m tolWF.XvIvUa Um n-
(4.S per oest.) are dowlj expeOed at s
! of 100 to llo- C. <312 to nV FJ. aiid are ^^
nptdl J abaovbed bf expnore to the vr;
ivc, OTsttDized (jataine salpbatc meh> whiMMt
aad, wbeo Mnm^j beated. beanwieg red, witb tbe
ied£>fa Tapors. beooniag Goalljr, apon igntttoa with
dowi^ bat wbollj diuBJFiaHd.
Qatnine Mlphste » mlabkr ib 740 parts of water and id 09
partx of al«ohol at 15' C. (59*> F.) : in ahoot 30 pan* of faoitiiia
vaier, aiwl in aboQt 3 parts of boiling aloobol ; in 40 parts m
glreeriii, in 1000 parts of chlorolbnB, and rery sparinglj aolabla
in etbar ; it ia very freelj aolable io dilate vt stroog acids, fono*
tw eolorieaa, bitter solntioiu, and its eolntioa in sa]{Aoric neid,
wbeo diloiad, exhibtlB a brigbl bine flnoreacence.
SolittiofHi of qoinine solpoaie are precipitated hj the alkaltae
bjdratea, carboutett, and lacarboDates, br lioke-water, bj tauutt
and picric acidx, bv potaasian ferrocjanic^ and br potasaio-nter-
coric iodide. Tbe precipitates vitt ualciara hydrate and wHb
the alkaline bTdratea are aolable io an abaodanoe of tbe prDoipi>
tant. Its aotntion in dilate hydrochlorio add giTea, apoa ue
addition of a solution nf bariata chloride, a wbJte precipitata of
bariaoi salphaie, tntmlable in nitric or hydrochloric acid^
Like all qaioine Balt«. qoinine palpitate affords an emerald-
green color, when to itB dilute solution cUorine-water, aad
■ab«e<)aently ammonia-water, in slight exeesi^ are addctl ; if tbe
addition of ammonia-water be preceded br a few drope* of a solu-
tion of potaasiam ferrucjanide, a red color will be prodoood.
QITISIKA
521
If, to a solution of 5 parta of quinine aulphnU! in 250 parts of
warm alcohol, 2 parts of dilute sulphuric acid, and snbsequently-
a solution of 2 parta of iodine in 20 parts of alcohol are gradu-
ally added, a precipitate of quinine iodo-aulpliat-e, or keravalhile,
(C;,H„NO,), + 3H,SO, + 2HI + 4I + 8H,0, will he
produced. This compound is almost insoluble in Fi"- IM.
water or cold alcohol, and, when crystallized from
lulling alcohol, forms small laminie, with a green,
melalHc lustre.
Examination!
Water. — An undue proportion of water, with
which the salt may have been moistened for the
jiurpose of increa.sing its weight, may be detected
by determining the loss of weight when dried at
100^ C. (212" F.). One gram of the well-mixed
salt, when dried at this temperature until the
weight remains constant, should afford a residue
weighing not less than 0.838 gram ; a greater loss
of weight will indicate the presence of mure than
8 molecules of water,
Quinidine, C'i'nchonine, and Ct'itchonidine Sul-
phates.— These associale alkaloids of ijuinine may
readily be detected by the application of I/essf'a
test, which is baaed upon the fact thai water at
oO-eO" C. (122-140" F.) dissolves quinine sul-
phate but sparingly, while the sulphates of the
other alkaloids are readily dissolved, and also that
when the cooled solution, after supersaturation
with ammonia- water, is shaken with a quantity
of ether which is sufficient to dissolve all the qui-
nine present, this quantity of ether is not sufficient
to dissolve the other alkaloids if they exceed cer-
tain limits.
For executing this test a simple test-tube of the
size represented in Fig. 154 may bo employed.
The internal diameter of the tube is about 1 centi-
meter, and its height 12 centimeters. It is pro-
vided with tiie marks Ji and C, The space below
Ji (to .4 in the figure) has the capacity of 5 cubic
centimeters, and the space between the lines B
and C the capacity of 1 cubic centimeter. The
application of the test is as follows :
0.5 gram of quinine sulphate and 10 cubic oen- ^^^
timeters of water at 50-60" C. (122-140'^ F.) are '^^ "
ebaken together in a test-tube several times.
After standing for ten minutes, 5 cubic centimeters of the cooled
and clear filtered solution are introduced into the graduated tube,
1 cubic centimeter of ether is added, and subsequently 5 drops of
a-wftter, spec. grav. 0.960, The tube is now closed wilh
K tightly -fitting cork, is agitnted gently, and allowed to stand for
several hours ; if the ethereal layer is now examined with a lens,
it should show no evidence of crystals.
The absence of crystals under the conditions named is evidence
of sufficient purity ; but the salt may still contain 0.25 per oent.
of cinchontne sulphate, 0,5 per cent, of quinidine aulphato, atid
about 1 per ceTit. of cinchonidine or homocinchonidine sulphates.
If these alkaloids are present in larger quantities, crystals will
separate in tlie ethereal layer, which are granular in the case of
homocinchonidine or cinchonidine, and concentrically grouped
needles if cinchonine or quinidine. The two former, homocin-
chonidine and cinchoaidiue, are most likely to be present in com-
mercial quinine sulphate that is not intentionally adulterated,
because of their liability to crystallize out along with the quinine
in the course of manufacture, but they should not be present in
an amount exceeding the above-named limits.
If the above-mentioned associate alkaloids are present in the
free state, they will remain for the most part undissolved wheu
the quinine sulphate is treated with thirty times its weight of
lx>iling water, and will also be indicated by a strong alkaline re-
action of the hot aqueous solution with litmus'paper, whereas
pure quinine sulphate is neutral in its action upon litmus.
Mineral lulmixlnri's are detected by a residue left after igniting
a little of the salt upon platinum-foil, or after dissolving a small
portion of the salt in ten limes its weight of boiling alcohol.
Ammonium sails are recognized by the odor of ammonia, and
by the formation of white vapors from a glass rod moistened with
acetic acid, when held in the orifice of a test-tube, wherein a small
portion of the quinine sulphate is heated with a strong solution
of potassium hydratt.
Chhridea and hydrocJilorates may be recognized in the dilute
solution of the salt in water, acidulated with nitric acid, by a
white, curdy precipitate with argentic nitrate.
SUarw acid may be detected in the above-described alcoholic
solution, by adding an equal volume of water ; the liquid becomes
turbid, but, on warming it gently, by dipping the test-tube in hot
water, it becomes transparent again ; the appearance of an oily
layer on the surftice would indicate the above fatty acid,
Salicin, sH'jir, and mannite may be detected in the solution of
the preceding test, if free from fatty substances, by mixing it, in
a porcelain capsule, with an amount of barium carbonate equal to
that of the quinine sulphate employed, and evaporating the whole
to dryness with constant stirring; the residue is trituratol with
a little water, and transferred upon a moist filter; the obtained
filtrate is evaporated at a gentle heat, upon a watch-glaits, and must
leave no residue, or only a very small one; if a residue remMus,
it is divided, and placed upon two watch-glasses, with one drop
QUIHtNA
523
of water upon eacb, and is again allowed to evaporate at a gentle
heal; then, upon the one glass, a small drop of concentrated sul-
phuric acid 18 allowed to fall from a glass rod or from a small
pipette (Fig, 155); a red color will be
produced if ealicin is present, a black Fio. 155.
one if sugar; mannite remains un-
changed, and may be detected on the
second watch-glass, by a few drops of
alcohol, which dissolve the manniie, and
leave it behind in small, aoiuular crys-
tals upon spontaneous evaporation.
Since quinine sulphate dissolves with-
out apparent change in strong sulphuric
acid, even when gently warmed, tliis
test may be directly applied for the de-
tection of admixtures of sugar, mannite,
or fatty acids, which will produce a black
coloration; a red coloration might be
indicative of the presence of salicin, but,
since many other compounds protluce
a similar reaction, the following addi-
tional test may be employed for salicin :
A small portion of the quinine sul- ■
pbate is dissolved, in a test-tube, in
about ten times its weight of water, acidulated with a few drops
of concentrated hydrochloric acid ; the solution is boiled for a few
minutes, when, if salicin he present, a white turbidity caused by
the formation of saliretin will take place.
QUININiB TANKAB.
CHININUM SEt: CniNIUM TANNtClJM.
Tannatt of Quinint or Qtii'nia. Quinine TannaU.
Ger. Oerbnaures Cliinip ; Fr. Tannate de quinine ; Sp. Tnnato dc quinlDH.
C«H„N,0,{C,.H,.0,)3-|-8H,0; 1-U9.
A yellowish- white, amorphous powder, which, when heated,
becomes brown, fuses, and at a strong heat is wholly dissipated ;
it is only sparingly soluble in cold water, requiring 480 parts of
it, but dissolves in about 50 parts of boiling water, forming a clear
solution, which becomes turbid on cooling; the addition of acids
increases the solubility to some extent; it is also quite sparingly
soluble in boiling alcohol, ether, and chloroform, but quite readily
soluble in warm glycerin; the alcoholic solution, when diluted with
water, displays a alight blue fluorescence. The aqueous solution
524 MANUjtL OF CEIEUICAL ANALYSIS.
of quinine tannate has an astringent, bitter taste, and a feebly
acta reaction ; it is precipitated by metallic salts, and assumes >
bluish-black color upon the addition of a few drops of solution of
ferric chloride. In contact with the alkaline hydrates, quinine
tannate assumes a fine red color, accompanied by the separstioa
of quinine; when treated with chlorine-water and ammonia, it
does not afford directly the characteristic green color which is
produced by mo^t quinine xaUti, but, in coiisequenoe of the tanoio
acid, yields a transient red color.
ExamlnBtioa :
In consequence of the capability of tannic acid of forming »erjf
variable compounds with quinine, according to the proportion or
manner in which it is emploved, an examination of the salt should
be made with reference to the amount of contained quinine, and
its freedom from any appreciable amount of the associate alka-
loids, qiiinidine, cinclionine, and cinchonidine. One gram of the
quinine tannate is intimately mixed with twice its weiglit of caustic
lime and sufficient water t<j form a stiff paste, and the mixture
dried upon the water-bath; the residue is then powdered, repeat-
edly extracted with hi>t chloroform, and the chloroforraio Holulion
evaporated in a tared beaker, dried at 120*^ C. (248° F.), and
weighed. The residue should weigh not less than 0.22 gram. In
order to determine the purity of the alkaloid thus obtained, the
contents of the beaker are dissolved in a little water acidulated
with a few drops of dilute sulphuric acid, filtered if necessary,
and then shaken with 3 to 4 cubic centimeters of ethor, and ammo-
nia water in excess. The two layers of liquid will remain clear
if only quinine is present, while a greater or less turbidity is evi-
denced in the presence of the other alkaloids. The residue from
the chloroformic solution is also adapted to the qualitative deter-
mination of quinine, by dissolving a small portion in chlorine-
water, and subsequently adding a few drops of ammonia- water,
when the cliaracteristic emerald-green coloration will be produced ;
if the addition of ammonia-water be preceded by a few drops of
a' solution of potassium ferrocyanide, it assumes a bright red
color.
Admixtures of Innnic or r/alUc add, sni/ar, mannite, or dextrin
may be recognized by their ready solubility in cold water in com-
parison with that of quinine tannate.
Ularck is detected by a blue color, when one drop of solution
of iodinized potassium iodide is added to a little of the quinine
tannaio shaken with some boiling water, and subsequently allowed
This look 18 the propi:: ,
COOPER MEDICAL COLLMG*.,
SAN FnANCISCO. OAL.
antt ii> not to he rfmo'-d fwrn Mfl
J
QUININA. 525
QXnNIN2l VALSRIANA8.
CHININUM 8EU CHINIUM VALERIANICUM.
Valerianate of Quinine or Quinia, Quinine Valerianate.
Ger. Baldriansaures Chinin ; Fr. Valerianate de qninine ; Sp. Valerianato de
quinina.
C,oH,,N30,.C,H,oO,+H,0; 444.
Thin, colorless, crystalline plates, of a pearly lustre, belonging
to the triclinic system, having a faint odor of valerianic acid,
and containing one molecule (4.04 per cent.) of water of crystalli-
zation; they are permanent in the air, fuse at about 90*^ C.
(194° F.) to a colorless liquid, and lose their water of crystalli-
zation at 100° C. (212° F.), becoming thereby partially decom-
posed and incompletely soluble in water ; when strongly heated,
they are entirely dissipated, emitting white, inflammable vapors.
Quinine valerianate is soluble in about 100 parts of water at
15° C. (59° F.), and in 40 parts of boiling water; in 5 parts of cold,
and 1 part of boiling, alcohol, but only sparingly in ether ; diluted
acids dissolve it freely, and strong sulphuric acid does so without
color, if heat is not applied. The aqueous solution of the salt pos-
sesses a bitter taste, is neutral in its action upon litmus, and, when
acidulated with sulphuric acid, displays a blue fluorescence with the
development of the odor of valerianic acid : with ammonia- water
it vielcts a white precipitate of quinine, which dissolves in a con-
siderable excess of the reagent, as also readily upon agitation with
ether. If chlorine-water be added to the solution, and subse-
quently ammonia-water in slight excess, an emerald-green color
is produced; if the addition of ammonia- water is preceded by a
few drops of a solution of potassium ferrocyanide, it assumes a
bright red color.
EKaminatioQ :
Stearic acid, 8U(/ar, and saliciriATe detected by agitating some of
the quinine valerianate with strong sulphuric acid, in a test-tube;
a black coloration would indicate one or both of the two former ;
a red one, salicin. In the case of a black coloration, a special test
for saliciv has to be made ; a little of the valerianate is agitated
with cold water, the filtrate is then evaporated at a gentle heat
to a small volume, and this is strongly acidulated with a few
drops of ccmcentrated hydrochloric acid, and heated ; a white
turbidity, taking place after a while, would indicate salicin.
Quinine hydrochlorate and sulphate may be detected, in the fil-
tered aqueous solution of the salt, acidulated with a few drops of
nitric acid, by testing portions of it with argentic nitrate for the
former, and with barium nitrate for the latter. They will be in-
dicated by a white precipit4\te with tlie respective reagent.
52d HANDAL op CBBHICAL ANALV8IB.
Zinc Valerianate or Acetate. — The absenw; of thcseor any oiber
mioeral salts, not readily volatilizablc, may be ascertained by ex-
posing the salt tu a red neat, upon platiiiam-foil, whereby iljeur-
ganic matter is completely dissipateil, leaving metallic oxides or
carbonates behind, if such be present; if a residue reraaios which
appears atraw-yellow while hot and white when cold, it may be
examined for zinc oxide by diasolving ii, in a test-tube, in a few
dropti of diluted hydrochioric acid, supersaturating the solution
with ammonia-water, and subseqtienily adding a little ammonium
sulphide ; an ensuing white precipitate will confirm the presence of
RBSORCZHtm.
Hetercin. MeUi-diozgbtntot.
Ger. Beaorciu ; Fr. Rcsorcine ; Sp, Resordna.
C.H,O,= C,H.{0U),; 110.
A crystalline powder, or short, thick prisms of the rhombic
system (Fig. 156), odorless and colorless when perfectly pure, but
on expttsure to the air af«uming a pinkish
color. It melts at 104° C. (219.2° F.), and
f
boils at 271° C. (519.8° F.), but becomes par-
tially volatilized at a nmcb lower tempera-
ture; when heated on platinum-foil, it bums
with a bright Dame, and is finally completely
dissipated.
Resorcin is very readily soluble in water,
alcohol, and ether, hut is insoluble in chloro-
form and carbon bisulphide. Its aqueous
;)lution is neutral in its action on litmus, pos-
sesses an intensely and disagreeably aweet
taste, and assumes a dark violet color on the
addition of ferric chloride, which disappears on the subsequent ad-
dition of ammonia; chlorinated lime also produces a transient
violet coloration. Its solution with ammonia-water by exposure
to the air becomes rose-red, then brown, by evaporation at a
gentle heat, green, finally dark blue, and, on the addition of an
acid, again dark red.
Resorcin reduces an animonincal solution of argentic nitrate and
an alkaline cupric solution on boiling ; upon the addition of bro-
mine-water to its aqueous solution until a permanent turbidity ia
produced, small colorless needles of tribrom resorcin, C,HBr,(OH),
ape separated, which are sparingly soluble in cold water, more
readily in hot water, and freely soluble in alcohol. With acetyl,
benwl, and succinyl chlorides, resorcin combines to form ethe^
8ALICINUM. 527
like compounds, in which the hydrogen atoms of the hydroxy!
are replaced by acetyl, benzoyl, and succinyl groups, as, c. ^.,
C.H/O-CjHjO),, CeH,(0-C.H,-CO)„ etc. When heated with
phthalic anhydride at 195° 0.(383° F.), the phthalein of resorcin,
or fiuorescein^ is produced, as follows :
2C,HeO, + C,H,0^ - C^n„0. + 2H,0.
Resorcin. Phthalic Fluorescein,
anliydride.
From the solution of the melted mass in alcohol it is precipi-
tated in white flakes by water, and crystallizes from alcohol in
small, dark brown, crystalline crusts, which dissolve in ammonia-
water, forming a red solution, and displaying an intense green
fluorescence. From the fluorescein, by the action of bromine,
tetra-brom fluorescein is produced, the potassium salt of which,
eoain^ C^HjKjBr^O,, is remarkable for the rose-red color of its
aqueous solution, accompanied by a green, or, when the solution
is very dilute, yellow fluorescence. By the action of pure nitro-
gen tetroxide on resorcin in ethereal solution, diazo- resorcin is
produced :
3CeH,0, -f N,0, - C„H,oX,0, -f 4H,0.
Resorcin. Diazo-rcsotcin.
The latter forms brown, granular crystals, having a green
metall'c lustre, which are dissolved by alkalies with a magnificent
blue-violet color.
A very characteristic test of resorcin is aftbrded by dissolving
a small portion in fuming sulphuric acid ; an orange-red solution
is formed, which gradually darkens, and changes after a time,
first to greenish-black, and then to pure blue, becoming purple-
red on gently warming.
BALIdNUM.
Salicin,
Ger. Salicin ; Fr. Saliciue ; Sp. Salicina.
C,,H„0,; 286.
Small, colorless, needle-shaped crystals or laminae, of a pearly
lustre, without odor, but having a very bitter taste. When heated
to 198° C. (888.4° F.) they melt to a colorless liquid, which, upon
further heating, becomes yellow, with the development of white
vapors having the odor of saiicylous acid, and becomes finally
carbonized; when strongly heated on platinum-foil they burn
entirely away, leaving no residue.
528 MANUAL OF CHBMICAL AHALTSI8.
Salicin is soluble in 28 parts of water and in 80 parts of alcohol
at 15® C. (59^ F.), in 0.7 part of boiling water, and iu 2 parta of
boiling alcohol, and is quite freely soluble in aqaeons aolatioua of
the alkaline hydrates and in acetic acid, but insoluble in ether
and chloroform. The aqueous solution is neuti^ in its action
upon litmus, possesses a bitter taste, and is pMcipitated by none
of the ordinary reagents.
With cold concentrated sulphuric acid, salicin affords a solution
having a fine red color ; upon the subsequent addition of water
the solution becomes colorless, and deposits a dark red powder,
insoluble in water and in alcohol ; when cautiously heated with
diluted sulphuric or hydrochloric acid, it is decomposed by absorp-
tion of water into glucose and saliyenin:
C„H„0, + H,0 - C.H„0. + C,H,0^
^ y ■ ■ .^ \ ^ •
Salicin. Sallgenin.
The latter is a handsomely crystallizable substance, readily
soluble in hot water, alcohol, and ether, and its aqueous solution
assumes, on the addition of a drop of a solution of ferric chloride,
an indigo-blue color. By long-continued heating with dilute acids,
saligenin is converted, by the elimination of a molecule of water,
into saliretiTiy CyH^O, a white or yellowish, resinous body, which
is insoluble in water, but soluble in concentrated acetic acid, alco-
hol, and ether, and is dissolved by concentrated sulphuric acid with
a red color.
The purity of salicin may be sufficiently determined, in connec-
tion with the above described reactions, by its leaving no residue
upon ignition, and by afl:brding a clear, colorless solution when 1
gram of the salicin is agitated with a mixture of 22 parts of water
and 5 parts of solution of potassium hydrate. It is also distin-
guished from the alkaloids, by its aqueous solution affording no
turbidity or precipitate with tannic or picric acids, potassio-mer-
curie iodide, or an ammoniacal solution of argentic nitrate.
BANTONINUM.
Santonin.
Gcr. Santonin ; Fr. Santonine ; Sp. Santonina.
C,.H„0; 246.
Small, flat, rhombic prisms, transparent, without odor or color,
and of a slightly bitter taste ; they fuse at 170^ C. (838^ F.), and
solidify on cooling to an amorphous mass, which, however, in
contact with a minute quantity of any of its simple solvents,
again assumes the crystalline form ; at a stronger heat, they vola-
tilize in dense, white, irritating, inflammable vapors. ^"hiJ. c?*'-
SANTONINUM. 529
dense in part unaltered on cooling, forming a white crystalline
sublimate ; at a red heat, with free access of air. they burn away
without residue.
Santonin is permanent in the air, and assumes a straw-yellow
color when e^tposed to solar light, without, however, undergoing
any chemical change. When moistened with concentrated sul-
phuric acid, it remains unchanged and colorless for a while (evi-
dence of the absence of salicin, which at once assumes a deep red
color); the mixture does not assume a bluish color upon the addi-
tion of a little powdered potassium bichromate (evidence of tlie
absence of strychnine*), nor does it afford any coloration with
concentrated nitric acid. When a few drops of a mixture con-
sisting of equal volumes of a very dilute solution of ferric chloride
and concentrated sulphuric acid are added to a crystal of santonin,
and the whole gently warmed, a fine red colc>r is developed, which
changes to purple and finally to violet.
Santonin is almost insoluble in cold water, requiring 5000 parts
of the latter for solution, and is not much more freely soluble in
acidulated water or in dilute acids; when agitated with the latter
and filtered, the filtered liquid has only a feebly bitter taste, and
affords no precipitate with tannic acid, potassio-mercuric iodide,
or with trinitrophenol (picric acid), either before or after the addi-
tion of a little solution of sodium acetate (further ev dence of the
absence of salicin, and of cinchonine, and other bitter alkaloids).
Boiling water dissolves j^^th part of santonin. It is, however,
readily soluble in diluted solutions of the alkaline liydrates, but
is reprecif)itated upon supersaturation with an acid, or upon the
addition of acidulous salts.
Santonin is also soluble in 40 parts of cold, and in 3 parts of
boiling, alcohol, in 160 parts of cold, or 42 parts of boiling ether,
in 4 parts of chloroform (distinction from cinchonine, which is
almost insoluble in chloroform), and more or less freely in benzol,
and in essential and fatty oils. The alcoholic solution possesses
an intensely bitter taste, is neutral in its action upon litmus, and
burns with a pale yellow flame (evidence of the absence of an
adulteration with boric acid); it becomes transiently carmine-
red upon the addition of a few drops of a concentrated solution
of potassium hydrate.
Santonin is the anhydride of santoninic acid, C,,Hjj>0^, forming
with the alkalies soluble, and, in part, well crystaliizable salts.
* Santonin and strychnine have some similarity in their appearance, and thin
fact has repeatedly been the cause of incidenlal mistakes and sad accidents.
They may, however, at once be distinguislied, besides their difference in taste,
by the solubiliiy of strychnine in diluted acids, by its insolubility in ether and
in solution of potassium hydrate, and by its reaction with concentrated sul-
phuric acid, in which it dissolves without color, but produces, upon the addi-
tion of a minute crystal of potassium bichromate, a bluish-violet color, which
succewively changes to violet, to red, and finally to yellow.
34
530
MANUAL OP CUBMrCAL ANALTeiB.
From tlio scciiuni sail, l>v the addilion of dilute hydrocliloric acid,
and direct ngilalion wiln elher, llie free santoninic acid may be
obtained : it forniB while, rliomhie tryslals, unalterable by expo-
sure to liglit, nnd sparingly soluble in cold water, but readily
soluble ill alcohol, ami which, at 120^ C. (248° F.). are deconi-
posfd into sanionin and water. The same decomposition lakes
plaoc upon the addition of sutplmric acid to llie aqueous aolatiim
uf the »alT, or when the latter is warmed with dilute hydrochloric
iieid.
The purity of santonin may, in roost itiKtances, be sufficiently
determined by the above described physical characters, and its
deportment with the simple 8olvcnl8, An admixture of alearic
iiet'il, or olhcr cryotallizable fatty acids, may be detected by their
lower fusing po ntw, and by the production of a greatiy stain, when
a little uf the santonin is warmed upon a piece of glazed paper at
a temperature nut exceeding 100° C (212° F.).
EODU ACETAS.
SODIUM SEU NATimiM ACETICUM.
Arelalt of Soilium. Sodium ArelaU.
Ger. ErelgFHum Nxlriuni ; Fr. Ac^intc dc lioiide; 8p. Acetnto dc n>u.
NuC,H,O,+ SH,0; 13fi.
Large, colorless, transparent, monoclinic prisms (Fig. 157), con-
taining three molecules (3(1.70 per cent.) of water of cryKtnllizitliou;
they are efflorescent in a dry, warm almos-
FiQ. l«. pliere.liquefy at 7.'i*'C.(lfi7-F.). and lose their
^^^^^ Wilier of crystallization lU 128° C. (2.i3.4° F.\
^^^^^^^^^ leaving the anhydrous salt as a white powder.
I^^^^^^^B The anhydrous salt melts at about 3W C.
Ej^HI^^^^H (572'' P.), without decompoRition, and solidilie*
l^^^^fl^^^l on cooling in a ervatailine form; at tempera-
r ^^^^^^^1 turcB above 315^ C, (ottU" F.) it is decomposed,
I ^^^^^^^^H with the evolution of empyreumalic, inflam-
I ^B^^^^^^^l tnalile fumes, leavingablack residuBof carbon
I ^H^^^^^^^P '^^^ Fo<linm car^Hinatc, which imparts to iho
^K^^^^^^^r flame a yellow color, changes moistened red lit-
1 ^^^^^^^^^ mus-pa]>er to blue, and eflervesces with acids.
^^^^^^ ISodium acetate is soluble in S parts of water
and in 30 parts of alcohol at 16" C. (59^ F.),
nnd in 1 part of boiling water and 2 pans of bmling uJcohnI; its
aqueous solution is neutral or nearly so, has a cooling, salinu tiute,
is not precipitated when dropped into strung alcohol, nur when
mixed with a diluted solution of so<lium carbonate, ur with a
SODIUM. 581
concentrated solution of sodium bitartrate ; it assumes a red color
upon the addition of a few drops of solution of a ferric salt,
evolves the vapor of acetic acid, when warmed with concentrated
sulphuric acid, and that of acetic ether, when heated with a mix-
ture of alcohol and sulphuric acid.
Examination :
Sodium chloride and sulphate are detected, in the solution of
sodium acetate, acidulated with a few drops of diluted nitric acid,
by testing it, in separate portions, with argentic nitrate and barium
nitrate; a white precipitate with the first reagent would indicate
chloride^ and with the second one, sulphate.
Carbonates^ silica^ and alkaline earths may be detected by dis-
solving a portion of the salt in water acidulated with hydrochloric
acid; effervescence will indicate carbonates; upon evaporating
the resulting solution to dryness, and treating the residue with
water, the silica will remain undissolved; and the solution, after
filtration, and the addition of sodium carbonate in slight excess,
will yield a white precipitate if alkaline earths be present.
Organic impurities will be indicated by a dark coloration when
a little of the salt is strewn upon colorless concentrated sulphuric
acid.
Metallic impurities may be detected in the aqueous solution ot
the salt, acidulated with hydrochloric acid, by a dark coloration
or precipitate upon saturation with hydrogen sulphide, or, after
neutralization with ammonia water, by the addition of ammonium
sulphide.
Estimation:
About 5 grams of the dry but uneflloresced crystals of the salt
are accurately weighed and ignited at a strong heat, in a porcelain
crucible, until inflammable vapors cease to be evolved; the resi-
due is then dissolved in water, and the solution, contained in a
beaker, after the addition of a few drops of solution of litmus, is
titrated w^ith a standard solution of oxalic or sulphuric acid (page
82) until, with the ap|)lication of a gentle heat to effect the com-
plete removal of the d.sengaged carbonic acid gas, a slight excess
of ac d has been employed, and the liquid assumes a brii»ht
cherry-red color. The excess of acid is then inversely titrated
with a standard alkali solution (page 87) until a decided blue
coloration of the liquid is just produced, when the number of
cubic centimeters of alkali solution, subtracted from that of the
acid first employed, will give the amount of the latter required
for the exact neutralization of the salt. One cubic centimeter of
the normal acid solution corresponding to 0.058 gram of sodium
carbonate, or, as its equivalent, 0.186 gram of crystallized sodium
acetate, the latter decimal, multiplied by the number of cubic
centimeters of normal ac d solution employed for neutralizat on,
will represent the amount of pure sodium acetate in the quan-
tity under estimation.
MANCAL OF CHIiMICAL ANALYSIS.
By tlie einploymeiit of fl.8 grams of crystalliaed sodium ■<»-
Ute, and a strictly normal Bolution of oxalic or sulphuric acid.
the number of cubic centimeters of acid required for the exact
neuirnlization of the salt after the above trealment, when multi-
plied by 2, will represent without further calculation the percent-
age pui-ily of the salt under examination.
b
SODII ARBENIAS.
BoniUM SEU NATRIUM AUSENTCUM.
Amenialeef Sodium. Sodium ArtfnMe.
Out. ArKPiiBaureeNRlrliiin ; Fr. Arffniate de somlc; Sp, Ars^nralo tie um.
NaHAsO^-t-THp; 311.9.
Cfjlorlc.^f, trati!i)inrcnt. mrinoclinic prisms (Fig, 158), containing
even molecules* (-10.38 per i.'«nt.) of wnH'r of crystallization;
tliey effloresce slightly in » dry atmos-
>io. 1.18. phere, and, when gently heated, lose f>
8nio!(!Cule3 (28.84 ]'er cent.) of water, be-
coming converted iiito a white powder,
whicli still contains two molecules (ll.i>t
per cent.) of water ; these, however, arc
expelled at 148° C. (21)9.4^ F.). when the
sail fu-scs.
t>od.um ameniate is soluble in 4 parts of
water at 15"' C. (59^ F.), but is very gpar-
injily soluble in cold alcohol : it is very
freely soluble in boiling water, and in HO
I arts iif boilingalcohol, Itp aqueous solu-
ti(m piisaesfies a mild, feebly saline taste,
and a si ghtlv alknl ne rcactioti : it gives
white prec pilales with barium and calcium salts, and with mag
ne.-iiiim and zinc sulphates, and a brick-red one with argentfc
nitrate, all of which are soluble in nitric acid ; it sufters no im-
mediate alteration by hydrogen sulphide, either n its alkaline
solution or when this is acidulated with acids; the latter mix-
lure, however, liecomes turbid upon warming, separating while
sulphur first, and subsequently yellow arsenic trisulphide. Fused
upon charcoal, before the blow-pipe, sodium arseniale gives the
garlic-liko odor of arsenic, and imparts a yellow color to the
flame ; heated, in a narrow tube, with a little potassium cyanide,
it forms a metallic mirror.
* WlicD crystallized Trom a ciild tolnlion, the islt cnntiiinB IS mnlfcntnnr
wnter of crysinllisiaiimi, bui rrndily low* H uinlccnlfs of HBier si ordlnnry i«ni-
pitralurpR. t>i-cnniingc<iiivi-rlril. witliout ch tinge or Inrm. into ft salt nflbe Above
compnaition.
soDitM^ 638
SODII BBNZOAS.
SODIUM SEU NATRIUM BENZOICUM.
Bemoate of Sodium, Sodium Bemoate.
6er. Benzoesaares Natrium ; Fr. Benzoate de soude ; Sp. Benzoato de sosa.
NaC,H,0,4- H,0 « C,H,-CO-ONa + H,0 ; 162.
Colorless, needle-shaped crystals, or a white, semi-crystalline
j)owder, containing one molecule (11.11 per cent.) of water of
crystallizatioQ, and efflorescent on exposure to the air. The salt
is odorless, or possesses but a faint odor of benzoin ; on being
heated, it first melts, with the evolution of irritating, inflammable
vapors, then chars, and finally leaves a blackened residue of an
alkaline reaction, which effervesces with acids and imparts an
intense yellow color to the non-luminous flame.
Sodium benzoate is soluble in 1.8 parts of water and in 45 parts
of alcohol at 15^ C. (59^ F.), in 1.8 parts of boiling water, and in
20 parts of boiling alcohol. The aqueous solution possesses a
sweetly astringent taste, and is neutral in its action upon litmus;
on the addition of a few drops of a dilute solution of ferric chloride,
a flesh-colored precipitate of basic ferric benzoate is produced,
and with hydrochloric acid it yields a crystalline precipitate of
benzoic acid, which, upon subsequent agitation with ether or
chloroform, becomes readily dissolved.
Examination :
Sulphates and chlorides may readily be detected in the diluted
aqueous solution of the salt, acidulated with nitric acid, by testing
it, in separate portions, with barium chloride for the former, and
with argentic nitrate for the latter; a white precipitate with
either of these reagents, insoluble in nitric acid, will reveal the
presence of such impurities.
Chloro-benzoic acid may be detected by the addition of hydro-
chloric acid to a concentrated solution of the salt, washing the
precipitated benzoic acid thoroughly with water, and subse-
quently heating a small portion of it, together with a little re-
cently ignited and moistened cupric oxide, on the looped end of
a platinum wire in the non-luminous flame; if a green or bluish-
green color is imparted to the oxi<le, the presence of chloro-bea-
zbic acid will be indicated.
The presence of the latter impurity, in case other chlorides are
absent, may also be detected by mixing 1 gram of the salt with a
few drops of a solution of sodium hydrate, allowing the mixture
to dry slowly, and subsequently igniting; the residual mass is
then extracted with water, filtered, and the filtrate, after super-
saturation with nitric acid, tested with argentic nitrate, when a
white, curdy precipitate will indicate an admixture or substitution
of sodium chloro-benzoate.
534 MANUAL OP CHBMICAL ANALYSIS.
Orfjanic impurities will in many instances be indicated by a
dark coloration when a little of the salt is added to concentrated
sulphuric acid; the mixture may subsequently be diluted with
twice its volume of water, a small crystal of potassium bichro-
mate added, and gently heated, when neither a green color nor
the development of the odor of bitter almi)nd8 should be pro-
duced ; in the latter case the presence of c.nnamic acid will be
indicated.
SODn BICARBONAS.
SODIUM SEU NATRIUM BICARBOXICUM.
BlcnrhonaU of Sodium. Sodium Bicarbonate.
Ger. Dopp<*lt koblenAaurcs Natrium ; Fr. Bicarbonate de soude ;
Sp. Bi carbon ato de sosa.
NaHCO,; 8i.
White, opaque masses, or crystalline crusts, consisting of mono-
clinic tables, or a snow-white powder, permanent in dry air, and
having the specific gravity 2.22. When heated to 100^ C. (212**
F.), the salt rapidly loses water and carbonic acid gas, amounting
to 36.9 per cent, of its weight, and leaves a strongly alkaline
residue of normal sodium carbonate, which melts at a red heat:
2NaIlC0, = Na,CO,-hII,0-f CO,.
Sodium bicarbonate is soluble in 11.3 parts of water at 15^ C.
(50° F.), and is insoluble in alcohol. The solution possesses a
mild alkaline taste and reaction, but docs not change the color of
turmeric paper; when heated, etlervescence takes place, and at
the boiling-point of the solution tlie salt is completely converte<l
into normal sodium carbonate, NajC()3. Solution of sodium V)i-
carbonatc afibrds no precipitate u[)on the admixture of a concen-
trated solution of sodium bitartrate, of tartaric acid, or of mag-
nesium sulphate.
Examination :
Noritml sodium rarhrmate will be indicated by a strongly alka-
line reaction of tlie salt to test-paper, and may be recognized in
the cohl aqueous solution by the |)roduciion of a white precipi-
tate on the addition of a solution of nia^nes urn sulphate, as also
by the following simple tests. 2 grams of the salt are dissolved
with as little a^ntation as possible, in a closed vessel, in 30 parts
of cold water, and the solution added at once to o grams of a cold
solution of 1 part of mercuric chloride in 20 [)arts of water; after
standing for three minutes, only a sliglit white turbidity should
liave occurred; a redd.sh-brown turbidity or a reddish deposit
will indicate the presence of more than 4 per cent, of normal car-
bouate. By the employment of G grams of tlie mercuric chloride
SODIUM. 535
solution, the occurrence of a reddish brown turbidity within
three minutes will indicate 3 per cent., with 6.5 grams, 2 per
cent., with 7 grams, 1 per cent., and with 7.5 grams, 0.16 per
cent, respectively of normal sodium carbonate. To insure the
accuracy of the above test, however, the absence of sodium chlo-
ride must be previously established, as the latter has the property
of dissolving the red mercuric oxychloride, aud its precipitation
would thereby be prevented.
Another method for determinin^ic the presence of normal car-
bonate in bicarbonate depends upon the conversion of calomel in
a concentrated solution of sodium carbonate into black mercurous
oxide, whereas it is not aft'ected by a solution of bicarbonate.
About 0.5 gram of calomel, 1 gram of the sodium bicarbonate,
and 1.5 grams of water are mixed, in a test-tube, and the mixture
well agitated for one minute; if the bicarbonate be free from
normal carbonate, the calomel will remain white, even after
standmg for twenty-four hours, whereas, with an admixture of
0.25 per cent, of carbonate, a slight grayish coating will be ob-
served within about twenty minutes, with 0.5 per cent, of car-
bonate it will appear gray within fifteen minutes, and with one
per cent, will become whitish-gray in a few minutes, and gradu-
ally increase in intensity of color.
Sodium chloruk and sulphate are detected in the solut on of the
salt, when supersaturated with diluted nitric acid, by testing it in
separate portions, with argentic nitrate for chloride, and with
barium nitrate for sulphate.
Sodium sulphite and hj/ posnlphi te (thiosulphfite) may be detected
in the aqueous solution of tlie salt, supersaturated with sulphuric
acid, by warming with a little potassium bichromate, when a
green coloration will be produced. The hyposulphite may also
be specially tested for, by supersaturating the solution of bicar-
bonate with acetic acid, and subsequently adding a little solution
of argentic nitrate; a white precipitate, gradually changing to
brown, will indicate hyposulphite: if chlorides also be present,
the resulting precipitate may be digested with ammonia- water,
when the argentic chloride will become dissolved, leaving brown
argentic sulphide if hyposulphite were present.
Ammanium salts may be detected by the odor of ammonia,
when a little of the salt is heated, in a test-tubi, with a concen-
trated solution of potassium hydrate, and by the formation of
white fumes, when a glass 'rod, moistened with acetic acid, is held
over the mouth of the tube.
Calcium and Matjnesium SaVs, — A small portion of the salt is
dissolved in diluted acetic acid, and subsequently tested with
ammonium oxalate, wlien a white precipitate will reveal the
presence oi calcium; to the filtrate, ammonium chloride, ammonia-
water, in slight excess, and solution of ammonium phosphate are
hehical analysis.
llien successively added, when the formation of a white, nrystal-
line precipitate will indicate maijne»ium.
Silica, MHallic Impurities, etc. — A Email portion of the salt is
dissolved in nn excess of diluted hydrochloric acid, the solution
evaporated to dryness, and the dry mass treated with water a^idu-
lilted with hydrochloric acid; a white insoluble residue will indi-
cate silica. The acid solution is then tested for metals, copper,
iron, atuminium. etc., by saturating with hydrogen sulphide, and,
lifter filtration, if necessary, by auperaatu ration with ammonia-
water, and the addition of ammonium sulphide ; a dark coloration
or a precipitate with these reagents would indicate one or iho
other of the above-mentioned impurities, which may be further
examined as to its nature by the methods of systematic analysis,
UK described on pages 51 to 59.
Estimation :
One hundred parts of sodium bicarbonate require for exact neu-
tralization 88.33 parts of citric, or 89,29 parts of tartaric, acid.
The quantitative estimation of the «alt may, however, be more
conveniently and accurately accomplished by ignitintf a weighed
portion, and dcleruiining its loss of weight, which, if the sail be
}niro, will amount to 36.9 per cent. The residue may then be
dissolved in water, and the amount of pure sodiutu carbonate
estimated volumctrically by means of a standard solution of oxalic
or sulphuric acid (page 82), as described under sodium carbonate,
on page 545; one cubic centimeter of the normal acid corre-
sponding to 0.053 gram of anhydrous sodium carbonate, or. as ilB
equivalent, 0.084 gram of s>>dium bicarbonate. If desired, the
accuracy of the result of ihc above e.sliination may be verified by
determining the ftmnunl of carbonic acid contained in a weighed
[lortion of the salt, as dcBcril>ed on page HG ; 100 parts of carbon
dioxide, COy corresponding to 190.9 parts of pure sodium bicar-
bonate.
The U.S. Pharmacoi>ceia directs that to neutralize 4.2 grams of
sodium bicarbonate should require not less than 49.5 cubiu oeuli-
meters of the volumetric solution of oxalic acid, and to nculraliKe
the same amount of the commercial salt, should require not less
than 47.5 cubic centimeters of the volumetric solution of oxalic
acid ; corres|)onding, in the first instance, to at least 99 per cent,,
and, in the second instance, to at least 95 per cent,, of pure
sodium bicarVjuatc,
L
This hook is thepropvr-^,
COOPER MEDICAL COa:-.C
SAN FRANCtSCO. OAL
an<i M not fn he ■mmtn-'d J) nnt ih.
A
SODIUM. 587
SODII BISXHiPHIS.
SODIUM SEU NATRIUM BI8ULFUR08UM.
Bisulphite of Sodium. Sodium Bisulphite. Acid Sodium Sulphite,
Ger. Doppelt scbwefli^sanres Natrium ; Fr. Bisulfite de soude ;
Sp. Bisulfito de sosa.
NaHS03; 104.
Small, opaque, prismatic crystals, having the odor of sulphurous
acid, an unpleasant, sulphurous taste, and an acid reaction. On
exposure to the air, the salt readily loses sulphur dioxide, and
becomes converted into sodium sulphate ; when strongly heated,
it decrepitates, and is resolved into sulphur and sodium sulphate ;
and when introduced, on a platinum-wire, into the non-luminous
flame, it imparts to the latter a persistent yellow color.
Sodium bisulphite is soluble in 4 parts of water and in 72 parts
of alcohol at 15" C. (59° F.), in 2 parts of boiling water and in 41)
parts of boiling alcohol. If hydrochloric acid be added to the
aqueous solution of the salt, it is decomposed, with the evolution
of vapors of sulphur dioxide, but without the separation of sul-
phur (distinction from hyposulphite).
Examination :
The dilute aqueous solution of the salt, acidulated with hydro-
chloric acid, should not aftbrd more than a slight cloudiness upon
the addition of a few drops of solution of barium chloride; a
white precipitate would indicate the presence of an undue amount
of sulphate.
Estimation :
About 0.2 gram of the salt is dissolved in a small portion of
water, in a beaker, a little mucilage of starch added, and subse-
quently a deci normal solution of iodine (page 93) allowed to flow
into the liquid from a burette until, with constant stirring, a per-
manent blue tint is just produced. One cubic centimeter of the
decinormal iodine solution corresponding to 0.0052 gram of sodium
bisulphite, NaHSOj, the number of cubic centimeters of iodine
solution required to produce this reaction will indicate, by simple
calculation, the amount of the pure salt in the specimen under
examination.
The United States Pharmacopoeia directs that if 0.26 gram of
the salt be dissolved in 10 cubic centimeters of water, and a little
gelatinized starch added, at least 45 cubic centimeters of the
volumetric solution of iodine should be required before a per-
manent blue tint appears after stirring (corresponding to at least
90 per cent, of pure sodium bisulphite).
•
UANllAt OF CUKMICAL I
BODn BORAS.
SODIUM 3EU NATRIUM BORICUM SEU BIBdHICUM.
Borate o\
n Pjfroborate.
1 of Sodium. Barai. Sodium Boratt. Sodiat
Ger. Borax ; Fr. Bnr»lc ilo Honde ; Sp Bcirnto de wim.
Na,B,O,+ 10H,O; 382.
Co]orIe88, transparent, hard, monocline prisms (Fig. 159), liar-
ing a specific gravity of I.7'i, and contaioing 10 molecules (47.12
[Mir cent.) oF water of cryatallizalion ; they
Fio. 1j9. afe ordinarily permanent, but slightly efllo-
rcsccnt in dry and warm air; when heated,
they undergo aqueous fusion with inlunie-
Hi.'.eiice and the eliininaliou of the water of
crystallization, and form a white porous
mass, which fuses at a red heat into a glass,
which is a powerful solvent for the metallic
oxides, forming colored fluxes. When pow-
dered borax is mixed in a porcelain cap-
sule with dilntod sulphuric acid and snbse-
r|uently with alcohol, and the mixture
ignited, the alcohol burns with a greenish
flame.
Borax is soluble in 18 jiarts of water at
15" C. (59° F.), in half its weight of boiling water, and, al 80" C.
(176° F.), in its own weight of glycerin, but insoluble in alcohol ;
its aqueous solution has an alkaline, sweetish taste, and an alka-
line reaction upon litmus and especially upon turmeric pa)ier; it
forms precipitates of insoluble or sparingly soluble borates with
the solniions of must earthy and metallic salts, and acta upon salts
of gold, silver, mercurv, and others, almost like potassium hydrate,
precipitating their oxides.
When added to mucilage of gum-arabic or Iceland-moss, or to
other similar vegetable mucilages, solution of borax thickens
them considerably, unless they contain an addition of grajte or
cane- sugar.
Ezaminatf on ;
A portion of ihe powdered borax, when dissolved in twenty
times its weight of warm water, should yield a complete and clenr
solution, remaiuing so after cooling; this solution may serve for
the following tests;
Sodium carbonalt is indicated by effervescence, or the rise of
gas-bubbles, when a portion of the solution is added to oonoen-
trated hydrochloric acid.
Calcium awA aluminiwn aalta (ii\nm) m\\ be indicated by a white
precipitate with solution of sodium carbonate. The presence of
alum may further bo contirined, when tested with ammoniam
SODIUM. 539
sulphide, by the production of a white precipitate of aluminium
hydrate, soluble in a solution of potassium hydrate.
Chloride and sulphate may be detected in the fiolution, after
dilution with three times its volume of water and acidulation with
dilute nitric acid, by the formation of white precipitates when
tested, in separate portions, with argentic nitrate for chloride, and
with barium nitrate for sulphate.
Phosphate may be detected by a white granular precipitate, upon
the addition of test magnesium mixture.
In order to ascertain the absence ©f arsenic acid or an arseniate,
which would aftbrd the same reaction with test magnesium mix-
ture, the precipitate may be collected, washed, and dried, and then
tested by heating a portion of it, mixed with a little exsccated
sodium carbonate, upon charcoal, and another portion, with a little
potassium cyanide, in a narrow glass tube; a garlic-like odor in
the first test, and a metallic mirror in the second, would indicate
an incidental contamination with an arseniate.
The presence of phosphate may also be definitely determined
by heating the solution of borax with a solution of ammonium
molybdate, acidulated with nitric acid, when a yellow, crystalline
precipitate of ammonium phospho- molybdate will be produced.
Nitrate will be indicated in the solution, strongly acidulated
with sulphuric acid, and tinged slightly blue with indigo solution,
by ensuing decoloration upon heating.
Metallic impurities may be detected in the solution of the salt,
acidulated with a few drops of hydrochloric acid, by a coloration
or •turbidity upon saturation with hydrogen sulphide, or, after
filtration, if necessary, and supersaturation with ammonia-water,
by the addition of ammonium sulphide.
SODII BROMIDUM.
SODIUM SEU NATRIUM BROMATUM.
Bromide of Sodium, Sodium Bromide,
Ger. Bromnatrium ; Fr. Brdmure de sodium ; 8p. Bromuro de sodio.
NaBr; 102.8.
Small, colorless or white, anhydrous, cubical crystals, or a crys-
tallioe powder, permanent in dry air. On exposure to a dull-red
heat, the salt melts without losing weight, and, at a full red heat,
it is slowly volatilized without decomposition. A fragment of the
salt imparts an intense yellow color to the non-luminous flame.
Sodium bromide is soluble in 1.2 parts of water and in 13 parts
of alcohol, at 15° C. (59° F.), in 0.5 part of boiling water, and in 11
parts of boiling alcohol. The aqueous solution possesses a saline.
540
MANUAL OF CHEUIOAL AN
faintly bitter taste, and a neutral or slightly alkaline reaction;
with argentic nitrate it yields a yellowish -white, curdy preoipi>
tute of argentic bniniide, which is insoluble in nitric acid, but
soluble in a Urge excess of ammonia -water (distinction from
argentic iodide); when dropped into a very dilute solution of
mercuric chloride, no reaction takes place (additional distinction
from sodium iodide), nor does it afford any precipitate ou the
addition of a concentrated solution of tartaric acid or sotlium
bitarlrate (distinction from potassium bromide).
Sodium bromide may also J)e distinguished from the iodide by
adding to the solution a little mucilage of starch, and sub.'veq uently
a few drops of chlorine-water; the solution of the bromide be-
comes yellow or yellowish-bruwn, wliilc that of the iodide assrimes
& deep blue color. If carbon disuiphidc be piured upon a solu-
tion of the salt, then chlorine- water added, drop bv drop, and the
whole agitated, the disulphide should acfjuire a yellow or yellow-
ish-brown color, without a violet tint,
ExaminatloD :
Moislurt, which may be contained in the crystals, as well as in
the granular form of tlie salt, is recognized, and may be quantita-
tively determined by ascertaining the loss of weight upon drying
St 100° C. (21*2" F.).
Sodium cfirlxinale will be indicated by a strongly alkaline reac-
tion, when a few frnRmenis of the salt are placed upon moistened
red litmus-paper, and may be recognized by the occurrence of a
white turbidity, when a little of the concentrated solution of the
salt is added to liine-waler.
SulpktUfs may be detected, in the dilute aqueous solution,
acidulated with a few drops of nitric acid, by a white precipitate
on the addition of a few drops of solution of barium nitrate or
chloride.
Bromnte is detected by placing a little of the powdered salt
upon a piece of while porcelain, and subsequently adding on©
drop of dilute sulphuric acid ; a yellow coloration of the moisl-
ened surface of the salt, or the developed odor of bromine, will
reveal the presence of bromate. The jiresence of the latter, in aa
aqueous solution of the salt, may also be detected by the libera-
tion of bromine upcm tlie addition of a few drops of dilute sul-
phuric acid, imparting a yellow color, whiisli, upon subsequent
agitation of the solution with a few drops of uarbou bisulphide,
will be absorbed by the latter.
Ghioridea may be detected, in the solution of the salt, bj com-
pletely precipitating it with argentic nitrate, digesting the washed
and still moist precipitate for some time with a cold, saturated
solution of ammonium carbonate, subsequently liltoring, and
supersaturating the filtrate with nitric acid; the production of a
white, curdy precipitate will reveal the presence of chloride.
The presence of smaller amounts of chloride, and less than that
^
SODIUM. 541
admitted in the officinal salt, may be detected H.'4 follows. 5 grams
of the powdered and well-driea salt, together with 6 grains of
pare powdered putaBsimn bichromate, are introduced into a small
flask, and lo grams of concentrated sulphuric acid are added.
The mixture is then submitted to distillation at a gentle heat, and
the distillate collected in a receiver or flask, containing a small
quantity of uminonia-water {¥ g. KiO). Bromine distils over, and
Pi I'. 100.
is dissolved by the ammonia water without color; but, if chlo-
rides are present, chloro-chromic anhydride, CrO,Clj, is produced,
distils over, and forms amtnoninm cliromate, wliicli imparls n
vellowish color to the distillate; by subsequently healing the
latter with a little hydrochloric acid and alcoiiol. the bright green
color of the chromic salt will be produced.
If sodium chloride i>r other salts are indicated by the above tests,
the extent of such nn jidmixnire may be apjiniximatelvartcertained
by preparing a solution i)f 1 gram of the dry. cryjtallized salt iji
about 10 timcH its weight of water, acidulated with a few drops of
diluted nitric acid, and completely precipitating it with a solution
of argentic nitrate: the pn'ci|)itate is collccieil upon a moist, tare<l
iilter, is washed, dried, iind, when comjdeioly dry. weighed. If
the salt was pure so<liiim bromide, the obtained argoniic bromide
should weigh l.>(24 grams; if it contained sodium or [mtassium
chloride, the weight will lie greater in proportion to the amount of
the admixture, since their molecular weights are lower; 1 gram
of sodium chloride, fur instance, would give2.4."> grams of argentic-
chloride.
The same test may also be employed to indicate the purity ft'
the bromide, by ascertaining the quantity of argentic nitrate
UANDAL 07 CIIEUICA
required to enmplelely precipilJite a Uefirite weight of sodium
bromide; I gram of wbicli requires l.fio grams of argenlic nitruie
for iirecijiitaiioD.
Nitratfa may readily be detected, if the salt be free from bro-
maie, by an enduing iiileiiso yellow coloration, when a solution of
a few fragments of the powdered salt in twenty times tlieir weight
of dilute sulphuric acia is heated to boiling. In the presence of
brornate, nitrates will be indicated by the development of the
odor of ammonia, when the suit, together with an equal weight
of iron and zinc filings, and solid potassium or sodium hydrate,
is gently heated, in a test-tube, with an equal volume of water.
If, however, ammonium salts be originally present as an ad-
mixture, the ammonia must first be completely expelled, by beat-
ing a portion of the salt with a strong solution of potassium
hydrate, after which the iron and zinc filings may be added, amt
tlie lesl subsequently performed for nitrates, as above described.
Estimatioa :
The eatimation of sodium bromide, or the amount of chloride
which may l>e contained therein, is most readily accomplished
volumciriuiilly. Two grams of sodium bromide, previously ra-
duccd to powder and carefully dried, arc d.ssolved in water to
the measure of 100 cubic centimeters. 10 cubic centimeters of
this solution, corresponding to 0.2 gram of sodium bromide, arc
then brought into a beaker, diluted with about 50 cubic centi-
meters of water, and, after the addition of a few dro]j8 of a solu-
tion of potassium chromate, a decinormnl solution of argentic
nitrate (page 9t>)is allowed lo flow into the liquid from a burette'
until, with constant stirring, a permanent reddish- brown colora-
tion is produced. If the salt is pure sodium bromide, 19.4 cubio
centimeters of the silver solution will be required to produou this
eSect, as containing OA'i gram of argentic nitrate, which corre-
sponds to 0.2 gram of sodium bromide, according to the equation
AgNO, : NaBr — 0,33 : 0.^. If the salt was pure sodium chloride,
170 103
34.18 cubic centimeters of the silver solution would be required
for its complete precipitation, in accordance with a similar pro-
portion; the difference in the amount of silver solution, required
lor 0.2 gram of the two salts, would therefore l>e 34.18 — ltf.4 «
14.78 cubic centimeters; from which it follows, that for each
0.1478 cubic centimeter of silver solution required in excess nf
19.4 cubio centimeters, in order to efl'ect complete precipitation, 1
per cent, of sodium chloride will be represented, as "^j^* — 0.147S.
It IS evident that the presence of sodium iodide, or otiier alkaline
chlorides or bromides, would influence the result in proportion to
the extent of the admixture.
The United Slates I'liarmacopueia directs that if 3 grams<^
the well-dried salt be dissolved in distilled water to ih<
SODIUM. 548
of 100 cubic centimeters, and 10 cubic centimeters of this solu-
tion be treated with a few drops of lest-solution of potassium bi-
ohrotnate, and then volumetric solution of argentic nitrate be
added, not more than 29.8 cubic centimeters of the latter should
be consumed before the red color ceases to disappear on stirring
(indicating the absence of more than 3 per cent, of chloride).
aODII CARBOHA8.
80niUM SEU NATRIUM CARBONICUM.
Carbonate of Sodium. Sodium Carbonnte.
Gcr. Eolilensaures N&triuni ; Fr. Cnrbonatc At soudc ; Sp, Carbonnto de torn.
Nn,CO, + 10H,O; 286.
Large, colorleps, trnnsparent, nionoclinic prisms (F g. Ifil),
having the specific gravity 1.440, and coDlaining 10 molecules
(62.85 per cent.) of water of crystallization ; they
eiBorcsce in dry air, losing readily 5 molecules Ffo. lOl-
of water, and falling into a while powder, whicli,
when heated to about 45^ C. (113" F.), sufters a
further loss of water, and is converted into a
salt of the composition Na,CO,+ Il,0 (.SV/(
Carlonas f'xsiccolus); thclaltcr salt, when heat-
ed to about 80" C.(176- F.), loses the remaining
molecule of water, and becomes anhydrous.
The crystals, when heated, undergo aqueous
fusion a"t 34° C. (93.2° F.), and, after the eviipo-
ration of the water, the anhydrous salt fuses at
a red heat, without undergoing further change.
Crystallized sodium carbonate is pohihlc in
1.6 parts of water at 15° G. (59° F.), and in 0.25
part of boiling water; or in other words, 100 parts of water dis-
solve, at 14° C. (57.2° F.). 60.4 parts, at 30- C. (06.8°) 833 parts,
and at 104° C. = 219.2° F. (the boiling point of the saturated
solution), 445 part?:, of crystallized sodium carbonate.* The salt
is insoluble in alcohol. Its aqueous .solution has a strong alka-
line taste and reaction; dropped into solution of tartaric acid, it
produces no precipitation ; it elfervcsccs with acids and acidulous
saltis and decomposes the soluble salts of the earthy and heavy
inetals, forming, with most of them, insoluble or sparingly soluble
* Bodiam carlionate, villi ten mnl^'Ciilce <tf nntrr nf cryslalll^Aiinti, is nllcrf-d
in iti «»lniion. M iiinr llip iHiilinjr.pdinl. inio n Mil wlih nnly one mnWiilp of
wnler of cryitalliMlioii, whicli is Wm 9i)lul)tf. und gives rise in ihe no'imnly In
tbe Milnblliiy of sodium cHrlmnnic. A aiiuiliir iasinnce IB met willi in sodium
■Dlpliiie and seTerH] oihcr wills.
644
UANL'Al. OP CHEMICAL
oarbonalcs or hydrates. The salt iiii|iarta an iiiicnse yellow color
to the non-luminous flame.
Examination :
Sodium hijdrntf is indicated in the solution of llie salt bv an
alkaline reaotion after complete precipitation with a slight exoew
of barium chloride, and subsequent (iltration; it maybe approxi-
mately estimated by agitating a fnw grams of the salt wilt abso-
lute alcohol, filtering the solution, and evaporatinj? the 5ltralv,
together with the alcoholic washings therefrom, to complete dry-
ness in a tared porcelain capsule ; the weight of the dried residue
will indicate approximately the amount of sodium hydrate con-
tained in the salt.
Chloride and sulphate are readily detected in the solution of the
salt, slightly an porfiatu rated with nitric acid, by testing it, in sepa-
rate portions, with argentic nitrate for the former and with barium
nitrate for the latter; a white precipitate in either case will re-
veal the presence of such impurities.
iSodium sulphide will be indicated by a black precipitate, wlicn
a solution of the salt is tested with ]ilumbio acetate or argentic
nitrate, and may also be recogniwd hy the development of the
odor of hydrogen sulphide upon the addition of a little hydro-
chloric acid.
Sodium sulphite and hyposulphite (thinsulphatc) may be deiecl«d
in the aqueous solution of the salt, 8n|K!rsatu rated with sulphuric
acid, by warming with a little riotass urn bichromate, when a
green coloration will be produced. The hyposulphite may ftl*»
be speciallv tested for, by supersaturating the solution of ihe car-
bonate Willi acetic acid, and subsequently adding a few drops of
solution of argentic nitrate; a white precipitate, cradnally changing
to brown, will indicate hyposulphite ; if chloritles ulsu be present,
the resulting precipitate may bo digested with ammonia- water,
when the argentic chhiride will become dissolved, leaving brown
argentic sulphide if hyposulphite were present,
Sodixim sulphocynnide and fermcynnide will be detected in the
solution of tlie salt, slightly su|MTsaturaled with hydiiHih loric
acid, by the addition of a few drojis of solution of ferric chloride;
a blood-red coloration Will indicate sulphocyanide. a blue colora-
tion or precipitate, the presence of ferrocyanide,
Calcium and Afai/nesium Saltt.^A small portion of the salt is
dissolved in acetic acid, and subsequently tested with ammoiiiiim
oxalate, when a white precipitate will reveal the presence of cal-
cium ; to the filtrate, ammonium chloride, ammonia-water, in slight
excQSH, and solution of ammonium phosphate are then suooee-
sively added, when the formation of a white, crystalline preoipi-
tate will indicate maynesivm.
Silica, Iron, and Altiminii. — A small portion of the salt is di*^
solved in an excess of dilnied liydri>chloric acid, the sohition
evaporated to dryness, and the dry mass treated with water aciilu-
SODIUM. 545
lated with hydrochloric acid ; a white insoluble residue will indi-
cate silica. The slightly acid solution may then be tested for iron
by the addition of a few drops of solution of potassium ferro-
cyanide, and, after supersaturation with ammonia-water, an
ensuing white, flocculent precipitate will indicate the presence of
alumina.
Arsenic. — A small quantity of the crystallized salt is dissolved
in about four times its weight of water, the solution is slightly
supersaturated with hydrochloric acid, filtered, if necessary, and
then warmed to about 60 to 70^ C. (140 to 158^ F.) ; while still
warm, hydrogen sulphide is allowed to pass into the solution until
it is nearly cooled, the flask is then corked, and allowed to stand
for twelve hours, when a flocculent, yellow precipitate would indi-
cate the presence of arseniate.
Estimatioii:
One hundred parts of crystallized sodium carbonate require for
exact saturation 48.95 parts of citric, or 52.44 parts of tartaric,
acid. Tlie quantitative estimation of the salt may, however, be
more conveniently and accurately accomplished volumetrically,
as follows. 26.5 grams of the crystallized salt are dissolved in
water to the measure of 500 cubic centimeters. Of this solution,
after the insoluble impurities have subsided and the liquid has
become perfectly clear, 100 cubic centimeters (corresponding to
5.3 grams of anhydrous sodium carbonate)are brought into abeakcr
or small flask, and a few drops of litmus solution are added. A
standard solution of oxalic or sulphuric acid (page 82) is then
allowed to flow into the liquid from a burette, until an excess of
the acid has been employed, and the liquid, after being heated to
boiling, in order to completely expel the liberated carbonic acid
gas, assumes a cherry-red color. The excess of acid is then in-
versely titrated with a standard alkali solution (page 87) until a
permanant blue coloration of the liquid is produced. From the
amount of acid required for the exact neutralization of the solu-
tion of sodium carbonate employed, the amount of the pure salt
contained therein may be calculated: one cubic centimeter of the
normal acid solution corresponding to 0.053 gram of anhydrous,
or 0.143 gram of crystallized sodium carbonate.
If desired, the accuracy of the above result may be verified by
determining the amount of carbonic acid contained in the salt,
according to the method described on page 86, from whicli the
equivalent amount of anhydrous or crystallized salt may readily
be calculated : 100 parts of carbon dioxide corresponding to 240.91
Earts of anhydrous, or 650 parts of crystallized, sodium car-
onate.
The United States Pharmacopoeia directs that to neutralize
7.15 grams of sodium carbonate should require not less than 49
cubic centimeters of the volumetric solution of oxalic acid (cor-
responding to at least 98 per cent, of pure, crystallized sodium
35
546
MANUAL OF CHEMICAL ANALYSIS.
carbonate; and to neutralize 2.65 grams of dried sodium car-
bonate {Sodii Carlonas Eocsivcatns) should require not less than
36.3 cubic centimeters of the volumetric solution of oxalic acid
(corresponding to at least 72.0 per cent, of anhydrous sodium
carbonate).
Table of the amount of cryslaUhed and anhydrous Sodlvm Carhonatf
contained in 100 parts of the solution of the salt of different specific
gravities (Schiff),
Specific
Per cenf. of
Percent, of
Specific
Per cent, of
Percent, of
gravity.
>'a..C(>3-fl0H..0.
Na..COs.
0.370
gravliy.
1.1085
.\a«rO;.-flOH..O.
26
Nb^COj.
1.0088
1
9.6:^5
l.<070
2
0.741
1.1076
27
10.005
1.0114
3
1.112
1.1117
28
10.376
i.oms
4 !
1.482
1.1 irs
29
10.746
1.0192
5
1.858
1.1200
;;o
11.118
1.0231
6
2.228
1.1242
81
11.48H
1.0270
7
ii.594
1.1284
82
ll,8r,9
1.0800
8
2.165
1.1326
88
13.230
1.0848
9
8.885
l.i;J68
84
12. ore
1.0388
10
8. 106
1.1410
85
12.971
1 . 0428
11
4.076
1.1452
86
18.841
1.0468
13
4.447
1.1494
37
18.713
1.0508
18
4.817
l.ir86
88
14.083
1.0548
14
5.188
1.1578
89
14.458
1.0588
15
5.r58
1.1620
40
14.824
1.0628
16
5.929
1.1662
41
15.195
1.0IJ68
17
6.299
1.1704
42
15.566
1.0708
IS
6.670
1.17^6
48
15.936
1.07^S
19
7.041
1 . 1 7S8
44
16.:i07
1 . 07S0
20.
7.412
I.l8:i8
45
16.677
1 08;;0
21
7.782
1.1 S78
46
17.048
1 0871
22
8.158
1.1916
47
17.418
1 0012
28
8.528
1.1959
48
17.789
i.oor.3
24
H.S94
j.i:ro2
49
18.159
1.0994
25
9. £64
1.2045
no
18.580
80DII CHLORAS.
SODIUM 8EU NATIUUM ClILORICUM.
Chlorate of Sodium. Alodium Chlorate.
Ger. Clilorsuurcs Natrium ; Fr. Chlorate do soiule ; Sp. Cloralo de sosa.
NaClO,; 100.4.
Colorless, transparent crystals of the regular system, j)reseniing
the form of a cul)e with dodecahedral and tetrahedral surfaces
(Kig. 1<I*2), and deviating the plane of jiolarization either to the
right ((/), or to the left (//). They are anhydnnis, and permanent
in dry air; when thrown upon burning cluircoal they deflagrate,
and when triturated or heated with readily oxidizable or combus-
SODIUM. S47
tible substflnces, sucli as sugar, sulphur, etc., a more or less violent
explosion eiiBuea. On being licated the salt meits, and afterwnnln
gives oft' oxygen, leaving finally, when strongly heated, a neutral
residue of sodium chloride, amounting to 'A'SS ]>er cent, of its
Fig. 103.
weight, and completely soUible in water; this residue imparts an
intense yellow color to llie n(m-!umiiions flame, and its aqueous
uolution yields with argentic nitrate a white, curdy precipitate,
insoluble in nitric acid, but readily soluble in ainmunia-water.
Sodium chlorate is soluble in 1.1 parts of water and in 40 partM
of alcohol at 15° C. (59° F.), in 0.5 part of boiling water, and in
43 parts of boiling alcohol. Its aqueous solnlion posstRses a cool-
ing, saline taste, and is neutral in its action iiponlilmus; when
mixed with concentrated liydruchloric acid, a dee}' greenish-yellow
color is jtroduced, and the i>dor of chlorine is evulvcd.
Ezamiiiatlini ;
Potassium chforale, when present as an admixture or substitu-
tion, will remain principally undissolved when the salt is treated
with three times its weight of cold water, and may be detected
in the saturated aqueous solution of the salt, by the formation
of a white, crystalline [)recipilate on t lie addition of aconcentratetl
solution of tartaric acid or sodium bitartrate.
Nitrates may be delected by first heating a portion of the salt,
ID a test-tube, with abimt twice its weight of si>lid potassium or
sodium hydrate, and a little water, in order to ascertain the ab-
sence of ammonium salts, and subsequently adding a few iron and
zinc filings, and again healing; if amnionium sitlts were found to
be absent, or, if present, have Iwen completely eliminated by
the previous heating with caustic alkali, the odor of ammonia,
developed upon the addition of the zinc and iron, will confirm the
presence of nitrates.
ChloriiUs and sulji/iates are delected in the aqueous solution of
the salt, acidulated with nitric acid, by white precipitates, when
tested with argentic nitrate for the former, and witii barium chlo-
ride for the latter.
Calcium sails may be detected in the dilute aqueous solution of
548 MANUAL OF CHEMICAL ANALYSIS.
the salt, by an ensuing white precipitate on the addition of a few
drops of solution of ammonium oxalate.
Metallic impurities will be recognized in the aqueous solution of
the salt, acidulated with hydrochloric acid, by a dark coloration
or precipitate upon saturation with hydrogen sulphide, or, after
filtration, if necessary, and neutralization with ammonia-water,
by the subsequent addition of ammonium sulphide.
80DII CHLORIDUM.
SODIUM BED NATRIUM CHLORATUM.
Chloride of Sodium, Common Salt. Sodium Chloride.
Gcr. Cblornatrium, Kochsalz ; Fr. Cblorure de sodium ; 8p. Cloruro de sodia
NaCl; 58.4.
Anhydrous, colorless, transparent, cubical crystals, often agglo-
merated into hollow, quadrangular pyramids, or a white, granular
powder, having a spec. grav. of 2.15 ; the salt is permanent in the
air, but slightly deliquescent when containing traces of magnesium
and calcium chlorides. When exposed to heat, sodium chloride
decrepitates, from the presence of interstitial moisture, melts at a
red heat, and volatilizes with partial decomposition at a high
temperature. It imparls a yellow color to the flame, and evolves
vapors of hydrochloric acid, when heated with strong sulphuric
acid.
Sodium chloride is almost equally soluble in water at all tem-
peratures: 100 parts of water dissolve at 0^ C. (32° F.) 35.52
parts, at 14° C. (57.2° F.) 35.87 parts, at 25° C. (77° F.) 36.13
parts, at 40° C. (104^ F.) 3().()4 i)arts, at «0° C. (176° F.) 38.22
parts, at 100° 0.(212^ F.) 39.61 i)arts, and at 110^ C. (230° F.),
the boiling-point of the saturated solution, 40.35 parts, ot the salt;
it is also soluble in glycerin, but not perceptibly soluble in abso-
lute alcohol, in ether, or in chloroform, but its solubility in alco-
hol increases with the quantity of water contained therein. Its
aqueous solution is neutral, and remains colorless upon the ad-
dition of chlorine-water (distinction from the alkaline bromides
and iodides); it forms white precipitates with the solutions of
those metallic salts whose chlorides are quite or almost insoluble
in water — for instance, with the salts of silver, bismuth, and lead,
and with the subsalts of mercury.
Examination :
Wott'r. — The amount of water, which may be present as inter-
stitial moisture, is readily determined by drying a small portion
of the salt at 150° C. (302° F.) until its weight remains constant.
Potassium chloride will be indicated in the concentrated aque-
ous solution of the salt, from which a portion of the sodium chlo-
80DIVH. 549
ride has been separated by crystallization, by the formation of a
yellow crystalline precipitate with an excess of solution of plati-
num chloride, and the subsequent addition of one-fifth of its
volume of alenhol; with the employment of a weighed quantity
of the salt, the precipitate of potassio-platinic chloride thus ob-
tained, after washing upon a filter wilh a mixture of alcohol and
ether, and drying at 1U0° C. {212" F.) until of constant weight,
may be finally weiglied, and therefrom the amount of potassium
chloride onlculated : 100 parts of potassio platinic uhloride, K,PtClg,
oorreapondinp to 30.50 parts of potassium chloride.
Xil7-ates. — To a little of the solution of the salt, contained in a
test-tube, a drop of solution of indigo is added, so as to impart to
the liquid a bluish tint, subsequently a few drops of concentrated
sulphuric acid, and the mixture gently heated ; if nitrates be pres-
ent, decoloration of the liquid will ensue.
A confirmatory and still more sensitive test is to dip a bright
zinc rod into a t«st-tube, or to suspend it in a small beaker
(Fig. 163), containing a little di-
luted sulphuric acid, to which a F'o. 163.
few drops of a solution of pure po-
tassium iodide, a little mucilage of
starch, and subsequently twice the
volume of the liquid of a solution
of the salt, has been adde<1 ; if nitrate
be present, a bluish coloration, ema-
nating from the zinc, will be pro-
duced in the liquid.
Iodides and Bromides. — A portion of the finely powdered salt
is digested with about ten times its weight of warm alcohol, and
the liquid, after being allowed lo cool, is filtered, and evaporated
to dryness at a gentle heat. The residue lliua oblaiued is dis-
solved in a little water, a little mucilage of starch added, and
subsequently chlorine-water, drop by drop, the liquid being gently
stirred with a glass rod. The presence of even minute traces of
iodide will cause a bluish coloration of the fluid ; when iodide alone
is present, the blue color will gradually become purple u]>on the
continued addition of the chlorine-water, and decrease, until it
finally disappears; but, when bromide also is present, the blue
color will not change to purple, but become successively brownish,
then orange, and finally yellow.
Alkaline and earth;/ sulphates are recognized in the dilute solu-
tion, acidulated with hydrochloric acid, by a white precipitate
with barium chloride.
Mat/nesium and calf-inm chlorides arc detected in tlie solution of
sodium chloride bv a wliite turbidity taking place upon the addi-
tion of a diluted solution of s<Kiium carbonate. They may be
distinguished and separaled from each other by adding to a solu-
tion of the salt, ammonium chloride, ammonia-water, and solution
550 MANUAL OF CHEMICAL ANALYSIS.
uf ammonium oxalate, when an ensuing white precipitate will
indicate calcium; the liquid is then filtered, and to tlie filtrate a
solution of ammonium or sodium phosphate is added, when the
formation of a white, crystalline precipitate will reveal the presence
of magnesium.
Metallic impurities may be detected by the occurrence of a dark
coloration or precipitate, when the solution of the salt, acidulated
with hydrochloric acid, is saturated with hydrogen sulphide, or,
after filtration, if necessary, and neutralization with ammonia-
water, by the subsequent addition of ammonium sulphide.
Estimation :
One gram of the powdered and dried salt yields, when com-
pletely precipitated by argentic nitrate, 2.450 grams of argentic
chloride. Its purity, when free from other chlorides, may also
be conveniently and accurately determined volumetrically, by dis-
solving 0.2 gram of the powdered and dried salt, in a beaker, in
about 20 cubic centimeters of water, and, after the addition of a
few d-rops of a solution of potassium chromate, allowing a deci-
normal solution of argentic nitrate (page 98) to flow into the liquid
from a burette until, with constant stirring, the red coloration of
argentic chromate remains permanent. The number of cubic cen-
timeters of the silver solution required to produce this effect,
when multiplied by the decimal 0.00584, will represent the
amount of pure sodium chloride in the quantity under estimation.
By the employment of exactly 0.292 gram of the salt, and ]»ro-
c.ecding as above, the number of cubic centimeters of the silver
solution re(|uircd to eft'ect complete precipitation, when multiplied
by 2, will indicate at once the percentage amount of pure sodium
cliloride.
SODII HYDRAS.
SODA. SODIUM SP:U NATRIUM IIYDHICUM. NATRIUM
CAUSTICUM.
CauHtie Soda. Soda. Sodium Hydrate,
(icr. Nutrinmhydroxyd, Aetzimtron ; Fr. Sonde causliquc; Sp. Sosa caustica.
NaOII; 40.
Hard, white, fusible masses, in flat, tabular fragments or sticks,
oF a fibrous fracture, or a coarse, white j>owder; it is very deli-
(jucscent in moist air, but afterwards becomes dry in consequence
of the absorption of carbonic acid gas, and the formation of sodium
carbonate. It melts below a red heat to a clear, oily liquid, and
at a strong red heat it is slowly volatilized unchanged. Heated
upon the looped end of a platinum-wire, it imparts to the non-
luminous flame an intense yellow color.
SODIUM. 551
Sodium hydrate is soluble in 1.7 parts of water at 15° C. (50° F.),
and iu 0.8 part of boiling water, with the evolution of lieat, and
is also freely soluble in alcohol; wlicn the concentrated aqueous
solution is cooled to— 8° 0.(17.(5^ F.), the hydrate, 2NaOH + 7H,0,
is deposited in large, transparent, monoclinic tables, which melt
at 6° C. (42.8^ F.). The solutions of sodium hydrate are highly
alkaline and caustic, and act destructively upon animal tissues;
when dropped into a diluted solution of plumbic acetate, it causes
a white turbidity, which disappears again upon continued addi-
tion of the caustic solution, without leavin<]^ a black residue (evi-
dence of the absence of sodium sulphide). When the concentrated
aqueous solution is dropped into strong alcohol, no precipitate
should take place, as its appearance would indicate the presence
of sodium carbonate, sulphate, chloride, or other salts, less soluble
in alcohol.
Sodium hydrate may readily be distinguished from ):>otassium
hydrate, by dropping concentrated solutions of the salts into solu-
tion of tartaric acid, care being taken that the acid reaction of the
solution predominates; sodium hydrate will yield no precipitate
unless containing potassium hydrate to a considerable extent,
while potassium hydrate forms a white, granular precipitate.
Examination :
Sodium carbonate may be detected in the solution of the hydrate
by effervescence, or by the formation of gas-l)ubV)les, o\\ the addi-
tion of a little acetic acid, and bv the occurrence of a white tur-
bidity upon the admixture of an equal volume of lime-water with
the aqueous soluticm of the hydrate.
Chloride and sulphate arc detected in the dilut<3d solution, super-
saturated with diluted nitric acid, by ensuing white precipitates
when tested, in separate portions, with argentic nitrate for the
former, and with barium nitrate for the latter.
Nitrate may be detected in the solution, supersaturated and
strongly acidulated with sulphuric acid, by the addition of a drop
of indigo solution, and gently heating ; if nitrate be present, de-
coloration of the liquid will ensue.
Cyanide may be detected in the dilute solution of the salt, after
the addition of a few drops of a solution of a ferrous and a ferric
salt, and subsequent sujjcrsatu ration with hydrochloric acid, by
the formation of a i)recipitate of Prussian blue.
Silica and aluminium salts may be detected by suj)ersatu-
rating the dilute solution of sodium hydrate with an excess of
nitric acid, and subsequently evaporating to dryness; the residue
is treated with warm water, and should be wholly soluble; an
insoluble residue would indicate silica ; the solution is filtered,
and the filtrate tested with ammonia- water, when the forma-
tion of a white, gelatinous precipitate would indicate aluminium
salts.
Metallic impurities are detected by a dark coloration or turbidity
552 MANUAL OF CHEMICAL ANALYSIS.
of the solution, when saturated with hydrogen sulphide, and, in
another portion of the solution, after previous supersaturacion
with hydrochloric acid.
Estimatioii:
2 grams of the dry sodium hydrate are dissolved in about 20
cubic centimeters of water, in a beaker, a few drops of litmus
solution added, and a standard solution of oxalic or sulphuric acid
(page 82) allowed to flow into the liquid from a burette until, with
constant stirring, the blue tint of the liquid is just changed to a
permanent pink. The number of cubic centimeters of normal acid
solution thus required for the exact neutralization of the above
amount of sodium hydrate, when multiplied by 2, will represent,
without further calculation, its percentage purity. By the employ-
ment of other amounts of the hydrate, the calculation may readily
be made, with the consideration that one cubic centimeter of the
normal acid solution corresponds to 0.04 gram of pure sodium
hvdrale.
If the sodium hydrate contains carbonate, the above estimation
will only be strictly correct when, in a weighed amount of the
hvdrate, the amount of carbonic acid contained therein is deter-
mined, as described on page 86: for 1 part of carbonic acid, 1.818
parts of sodium hydrate are deducted from the found amount of
the latter, and the remainder then calculated as pure sodium
hydrate.
The United States Pharmacopajia directs that to neutralize 2
grams of soda should require not less than 45 cubic centimeters
of the volumetric solution of oxalic acid (corresponding to at least
90 per cent, of absolute sodium hydrate).
For the determination of the strength of aqueous solutions of
sodium hydrate, as based upon the specific gravity of the latter,
see Liquor Sodiv^ p-'^gc 418.
SODII HYPOPHOSPHIS.
SODIUM SEU NATRIUM HYPOPIIOSPHOROSUM.
Ilypojilumphite of Sodium. Sodium Ilypophonphite.
Ger. Unterphosphorigsaiires Natrium ; Fr. llypophosphite de soudc ;
Sp. Hipolosfilo de sosa.
NaII,PO,-fII,0; 106.
Small, colorless, transparent, rectangular tables, of a pearly lus-
tre, or a white, granular ))owder, containing one molecule (17 per
cent.) of water of crystallization, and deliquescent on exposure to
the air. When heated in a dry test-tube, the salt first loses its
water of crystallization, and afterwards evolves spontaneously
infhunmable hydrogen phosphide, burning with a bright light; a
SODIUM. 553
residue of sodium pyrophosphate, containing traces of red amor-
phous phosphorus, is left bcnind, which imparts an intense yellow-
color to the non-luminous flame.
Sodium hypophosphite is soluble in 1 part of water, and in 30
parts of alcohol at 15° C. (59° F.), in 0.12 part of boiling water,
and in 1 part of boiling alcohol (distinction from barium and cal-
cium hypophosphites and sodium phosphate, which are insoluble
in alcohol); it is insoluble in pure ether. Its aqueous solution
has a sweetish, saline taste, a slightly alkaline reaction, and is
gradually oxidized on exposure, especially when warm ; it affords,
when much diluted, a white ])recipitatc with argentic nitrate,
which quickly turns brown, and is converted into metallic silver:
when acidulated with hydrochloric acid and added to an excess of
solution of mercuric chloride, it first produces a white precipitate
of mercurous chloride (calomel), and, on further addition, metallic
mercury is separated.
Examination :
Carbonates may be detected in the aqueous solution of the salt
by eftervescence on the addition of an acid, and by the production
of a white precipitate when added to lime-water.
Soluble phosphates and ])hosphites will be indicated in the aque-
ous solution by a white precipitate on the addition of a few drops
of solution of calcium chloride; the presence of phosphates may
also be recognized by adding to- the solution a little test mag-
nesium mixture, when a white, crystalline precipitate will be
produced.
Sulphates and chlorides may be detected in the aqueous solu-
tion, acidulated with nitric acid, by testing it, in separate portions,
with barium chloride for the former, and with argtMitic nitrate for
the latter; a white precipitate in either instance will reveal the
presence of such impurities.
Calciinn and Potassium Salts, — The former will be indicated by
a white preci])itate on the addition of a fe.w drops of solution ot
ammonium oxalate, and the latter by a white, crystalline precipi-
tate on the addition of a concentrated solution of tartaric acid or
sodium bitartrate.
Metallic lynpurities may be detected in the solution of the salt,
acidulated with hydrochloric acid, by a dark coloration or a j^rc-
cipitate with hydrogen sul|>hide: or, after filtration, if necessary,
and supersaturation with ammonia-water, by the addition of am-
monium sulphide.
MANUAL OF CIlEMtCAL ANALYSIS.
SODII BTPOSULFHIS.
SODIUM SEU NATRIUM HYPOSULFUROSUM SEU
SUBSULFUHO?'UM SEU THIOSULFURICUM.
HgpotiilphUt •>/ Siidiiim. Sodiaiu ITypoiiilphiU. Sodinia Thiotulphaia.'
tier. Uulerscliwpfliiisnnre9 Niilriiini, Tliinscliwpfplsaiirpg Sntriiira; Fr. Uypo-
siilliiede soude; Sp. Uipnsuilito An iwisa.
N!.,S,0, + 51I,0 - S0,^g^-' + 5n,0 ; 24S.
Lnrtrc. colorless, transparent, monocHiiic prisms or tables (Fig.
Ki-l), having tlie s]n.'citic gravity 1.73G, and containing five mole-
tuleri {Sll.S per cent.) of water of crystalliza-
Fio. IGI. tion ; tliey arc |X"rmanent at ordinary tern-
fl>cr.iture.s, but cfilorcsceot in dry and warm
air; wlicii quickly heatod to about 48'' C.
(11S.4°F.), the salt melts in its water of crys-
tallizjktion, and, after becoming efflitrepced by
eX|^K>siirc to a gentle heat, and subsequently
heating to H>0° C. {%V2° F.), the entire
ainonnt of water of crystallization is cx-
jiclled ; at a higher temperature it is decom-
|nised, with the cvohituni i>f vapors of sul-
phurous acid andsul)iliur, wl^ich take fire, and
imrn away, leaving bohiud a reddish-yellow
residue of ni-uiral sodium suljihate, cuntaiuing a little sulphide.
Si.i!iuui hvposulpliiic is soluble in l.--| pans of water at l."i° G.
(.')'.i° F.). and in half its weiglit of boiliug water, in the latter c:ise
attended liv ]>arlial deeorujM>silion of the salt ; it is also soluble
in oil of inrpeiitine, ami causes the odor of the latter to disap-
pear, but is ins,.]ul.ie in aleohol. The aipieuus s^hition has a
CDuHng and afterward a bitter taste, and a ieebly alkaline reac-
lifui: on ex[»>sure to ihe air, it is -.aadually dueorupo.-ied. the
hypi'sulphile being (.■nuverloil into suljiliur and .•ioitiurn sulphite,
which latter salt, on exposure of the s.);ali.>u to the air. is further
dceoniposed int.. sulphur and so-lium sulphate; when dropped
into diluted liydroehlorie, nitric, or sulphuric acid, solution of
siilium hyposulphite gradually heeouies turbid, sulphur being
precipitated, :tiid sulphurous acid diseiigawd.
With solul.ou ol harLiini cldoridc. a cone Titrated solution of
sodium hyposulnhitc forms a white prc.-ipitatc, wliich dissolves,
• SincT til.' dinciivry of tlii' ncul ll.Sd., tlif ;t|>|.Hl!itioii ol
SODIUM. 555
however, upon sufficient dilution with water (evidence of the
absence of sodium sulphate); when dropped into a dilute solution
of argentic nitrate, a white precipitate h formed, which soon be-
comes yellow, and finally black ; when, however, on the other hand,
the argentic solution is dropped into the solution of sodium hypo-
sulphite, the ensuing white precipitate of argentic hyposulphite is
redissolved upon agitation, and the solution remains clear as long
as sodium hyposulphite is in excess. With solution of ferric
chloride, a transient violet coloration is produced, with the for-
mation of sodium tetrathionate, while the ferric salt becomes re-
duced to the ferrous state :
Fe,Cl,+2Na,SA = 2FeCI,-hNa,S,0, + 2NaCl.
When iodine, either alone or dissolved in alcohol, is added to
solution of sodium hyposulphite, it is immediately decolorized,
sodium iodide and tetrathionate being formed:
2Na,S,0,.5ir,0 4- I, = 2XaI -h Na,S,0. + 1011,0.
V / .
(248) (120.G)
This reaction takes ])lace in the |>roportion, ai)proximately, of
one part (126 G) of iodine to two parts (24S) of crystallized sodium
hyposulphite; a solution in these i)roportions dissolves iodine
readily, with a brown color, but it is decolorized again upon the
restoration of the above proportions by the addition of sodium
hyposulphite.
Solution of sodium hyi>osulphite is a solvent for several
otherwise insoluble compounds, as argentic oxide, argentic iodide,
bromide, and chloride, plumbic iodide, plumbic and calcium sul-
phates, etc.
Examination :
Sodium sulphate is detected by the occurrence of a white ))re-
cipitate, when a solution of 1 part of the salt in 80 parts of water
is tested with barium nitrate.
Sodium carhonate is indicated by elfervesccnce, when a concen-
trated solution of the salt is dropped into diluted acetic or hydro-
chloric acid.
Chloride mav be. detected bv fusin<^ the salt with twice its
weight of pure potassium nitrate, dissolving the fused mass in
water, and, after acidulating with nitric acid, testing with ar-
gentic nitrate; a white curdy precipitate will reveal the presence
of chloride.
Sodium sulphide will be indicated in the aqueous solution of
the salt by the formation of a white precipitate with zinc acetate,
a black precipitate with an ammoniacal solution of argentic ni-
trate, and a violet-red coloration on the addition of sodium nitro-
prusside.
556 MANUAL OF CHEMICAL ANALYSIS.
Sodium sulphite will be indicated by its more sparing solu-
bility in water, and may be recognized in the aqueous solution
by the production of a brown-red color with sodium nitro-prus-
side; if sodium sulphide is also present, the latter must first be
removed by precipitation with zinc acetate before the application
of the above test.
Calcium salts may be detected in the aqueous solution of the
salt by the formation of a white precipitate when tested with
ammonium oxalate.
EBtimation :
The estimation of the salt may be readily and accurately ac-
complished volu metrically by the following process, which is
based upon its property of combining with iodine, with the for-
mation of sodium iodide and tetrathionate, as above described.
1 gram of crystallized sodium hyposulphite is dissolved, in a
beaker, in 10 cubic centimeters of water, a little mucilage of
starch is then added, and subsequently a decinormal solution of
iodine (page 03) allowed to flow into the liquid from a burette
until, with constant stirring, a permanent blue tint is produced.
If the salt is perfectly pure, 40.32 cubic centimeters of the iodine
solution will be thus required ; if a smaller amount of the iodine
solution effects a blue coloration of the liquid, the salt is impure,
and the calculation may readily be made witli the consideration
that 1 cubic centimeter of the decinormal iodine solution corre-
sponds to 0.0248 gram of pure crystallized sodium hyposulphite,
NajSjOj-f 511^0. If the salt should have been found to contain
sodium sulj>hide as an impurity, the latter must first be removed
from the solution by precipitation with zinc acetate, and filtered,
before being subjected to estimation with the solution of iodine.
The United States Pharmacopoiia directs that a solution of 2
grams of the salt in 10 grams of water, agitated for a short time
with 1 gram of iodine, should yield a colorless liquid, with at
most only a faint, white opalescence (corresponding to about 93
per cent, of pure sodium hyposulphite).
SODII lODIDUM.
SODIUM SEU NATRIUM lODATUM.
Iodide of Sodium. Sodium Iodide.
Ger. Jodnatrium ; Fr. lodure de sodium ; Sp. loduro de sodio.
Nal; 149.(1.
A white, granular powder, or minute, colorless, cubical crys-
tals, anhydrous when crystallized at temperatures above 40® C.
(104° F.), or monoclinic prisms, containing two molecules (19.35
SODIUM. 557
per cent.) of water of crystallization, when crystallized at ordi-
nary temperatures. The salt is deliquescent on exposure to the
air, and in a moist atmosphere becomes gradually decomposed,
with the liberation of iodine and absorption of carbonic acid, ac-
quiring thereby a reddish color; when exposed to heat, the salt
fuses with the liberation of iodine and absorption of oxygen, and
at a full red heat it is slowly volatilized. When a little of the
salt is heated, in a test-tube, either in concentrated sulphuric acid,
Of with a little potassium bisulphate, violet-coloreci vapors of
icAline are evolved ; and when dissolved in a little water, a few
drops of chlorine-water added, and the mixture subsecjuently
shaken with a little chloroform or carbon bisulphide, a fine pur-
ple or violet color will be imparted to the latter. A fragment of
the salt, when heated upon the looped end of a platinum-wire in
the non-luminous flame, imparts to the latter an intense yellow
color.
Sodium iodide is soluble in 0.6 part of water and in 1.8 parts
of alcohol at 15® C. (59° F.), in 0.3 j^art of boiling water and in
1.4 parts of boiling alcohol, and is also freely soluble in glycerin.
The aqueous solution ])ossesses a saline, slightly bitter taste, and
a neutral or feebly alkaline reaction ; it gives no precipitate with
tartaric acid, with sodium bitartrate, or with sodium carbonate,
but forms a yellowish one with argentic nitrate, insoluble in
diluted nitric acid or ammonia- water, and a vermilion- red one
with mercuric chloride, soluble in an excess of either reagent.
Examination :
Impurities and admixtures, less soluble in alcohol, are indicated
b}' a white turbidity or granular deposit, when a saturated aque-
ous solution of the salt is dropped into an excess of strong
alcohol.
Potassium salts are indicated by a white, crystalline precipitate
in the concentrated aqueous solution, when added to a strong
solution of sodium bitartrate.
Chloride and bromide may be detected by dissolving 1 gram of
the salt in 10 cubic centimeters of ammonia water, and ajiitatino:
the solution with a solution of 1.2 grams of argentic nitrate in 20
cubic centimeters of water; the mixture is then filtered, and the
filtrate supersaturated with 7 cubic centimeters of concentrated
nitric acid, when no immediate cloudiness of the liquid should be
produced; a white turbidity or precipitate would indicate the
rresence of more than about 0.5 per cent, of chloride or bromide,
f a ])recipitate is formed, it may be collected u])on a filter,
washed, and subsequently transferred to a test-tube, and agitated
with chlorine-water; if argentic chloride, it remains unchanged;
if bromide, the chlorine-water will assume a yellowish or reddish
color, which, on agitation with chloroform, will be transferred to
the latter.
Carlonate may be detected, in the aqueous solution, by a white
558
MANUAL OF CHEMICAL ANALYSIS.
turbidity when mixed with twice or thrice its volume of lime-
water, and will also be indicated by a strongly alkaline reaction,
when a few fragments of the salt are placed upon moistened red
litmus-paper.
Sxdphate may be detected in the diluted solution of the iodide,
previously acidulated with hydrochloric acid, by a white precipi-
tate with barium chloride.
lodate may be detected in the aqueous solution of the salt, by
adding a few drops of mucilage of starch, and then a few drons
of a concentrated solution of tartaric acid ; if iodate be present, a
violet or bluish coloration will ensue. Or, the aqueous solution,
mixed with a few drops of a concentrated solution of tartaric
acid, mav be agitated with a little chloroform or carbon bisul-
])hide, when the latter will assume a red or violet color if iodate
be present.
fsodinm nitrate may be detected in the aqueous solution, if the
salt be free from iodate, by the addition of a few drops of muci-
lage of starch, and subsequently adding a little of this liquid to a
mixture of zinc and diluted hydrochloric acid, in which the de-
velopment of hydrogen is actively taking place; if any nitrate ho
present, the liquid will gradually assume a reddish-violet or blue
Fio. 105.
color. If iodate be present, the presence of nitrate may also l>e
determined bv completely prcci|)itating a solution of the salt with
argentic sulphate, liltoriug, and adding to the tiltrate, in a test-
tube, a concentrated solution of ferrous sulphate, and afterwards
concentrated sulphuric acid, so as to form two layers (Fig. 1(>5):
a dark-l)rown coloration at tiie line of contact of the two liquids
will reveal the presiMice of nitrate.
SODIUM. 559
Estimation:
A quantitative estimation of the purity of sodium ioilide may
be made by dissolving 1 gram of the salt in 10 grams of ammo-
nia-water, ai:d adding to the solution a solution of argentic nitrate
until a precipitate ceases to be produced ; the j)recipitate of argen-
tic iodide is then collected upon a filter, well washed with water,
and finally drie<l at 100° C. (212' F.) until of constant weight. It
the sodium iodide is pure, l.oOO grams of argentic i<xlide should
be obtained, or 100 parts of argentic iodide e(>rrespond to 68.8J^
parts of s(Klium iodide.
The estimation of the purity of sodium iodide may also be
accomplished vol u metrically by the follo\ying method. This is
based upon the fact that mercuric chloride precipitates from a
solution of sodium iodide, red mercuric iodide, which is soluble
in an excess of a solution of sodium iodide with the formation of
a soluble double salt, and the solution of the latter again yields
upon the addition of mercuric chloride a j^recipitate of mercuric
iodide :
2NaI -f HgCl, = Hgl, H- 2NaCl,
llcil^ + 2NaI = llgNaJ,, or
4NaI + IlgCl, = IlgNa^I, + 2NaCl.
5^)8.4 271
(5) (2.20)
2.26 grams of mercuric chloride are dissolved in water to the
measure of 100 cubic centimeters, and o grams of the sodium
iodide under examination are likewise dissolved in water to the
measure of 100 cubic centimeters.^ 10 cubic centimeters of the
sodium iodide solution are then brought into a beaker, which is
placed upon a sheet of white paper, and to the solution is added,
from a burette, the above solution of mercuric chloride until, with
constant stirring, a permanent precipitate of mercuric iodide is
just produced. The number of cubic centimeters of the mer-
curic chloride solution required to produce this reaction, when
multiplied by 10, will re])resent the percentage amount of pure
sodium iodide contained in the salt. The accuracv of the result
of the estimation by the above method is not influenced by
the presence of chloride or of considerable amounts of bromide.
* The results attained by this nictliocl are rnnrlcred more accurate, when.
instead of dissolving the mercuric chloride and sodium iodide in water, alcohol
17 *! 100
of 17.5 per cent, by volume is employed. From the formula x = - ' ' - ,in
n
which n represents the percentai^e strenjjth of the alcohol to be diluted, tho
volume of alcohol may be calculated which must be added to the water in order
to obtain 100 parts of alcohol of IT.Ti per cent, by volume.
560 UANDAL OF CBBHICAL ANALTSIS.
SODII NITRA8.
SODIUM 8EU KATRIUM NITHICUM.
Nitrate of Sodium. Chili Saltpetre. Sodium A'ilratt.
Gcr. SalpctcraaiircB Xatriuiu ; Fr. Azotnle de goude ; Sp, Kitrato de fOM.
KaNO,; Ho.
Anhydrous, colorless, transparent, obtuse-rhombohedral crys-
tals of the hexagonal system (Pig, 166), having a specific gravity
of 2.26; they are deliquescent in damp
Fio. 166. air, and generally of a moist appearance.
^--.^ The salt melts at 312" 0. (594^ F.) with-
^j^" 7^ out decomposition, but, on further heating,
rf^ ^^ becomesdecomposed, with the evolution of
^^. ^^^^^k oxygen, and leaves a residue which emits
^^^^^^^^^^ nitrous vapors on the addition of sulphuric
^^^^^^^ acid; when thrown upon burning coals,
^^^ the salt deHagrales, altiiough not so vio*
lentty as putas-sium nitrate, and imparts
an intense yellow color to tne non-lutuinuus flame.
Sodium nitrate is soluble in 1.5 parts of water at 15° C. (59°
¥.), and in 0,6 part of boiling water; it is but sparingly soluble
in cold alcohol, but sohibJc in 40 parts of boiling alcohol. The
aqueous (solution has a, sharp, cooling, saline, and slightly bitter
taste, and is neutral in ils action upon litmus; when heated with
potasKiiim chluriJe or carbonate, it is decomposed, with the forma-
tion of potassium nitrate and siMlium chloride or carbonate.
Its concenlrated solution may readily be distinguished from
that of poiassiuin nitrate by not being acted upon by a solution
of KCKiium bitnrtrate, which gives a white, granular precipitate
witii polas,-iinrn nitrate.
Exammatlon :
Cfttoriiks and sul/iliates are detected in the diluted solution,
after acidulatiim with diluted nitric acid, by while precipitates
when tested, in wparate portions, with argentic nitrate for chlo-
ride, and with bariuin nitrate for sulphate.
.SKiium Iinlide ami loil'ite.-^To a solution of the salt a few drops
of iin aqueous solution of hydrogen sulpliide are added, then a
little iiincilage of starch, and finally a few drops of chlorine-
water allowed to flow upon the surface <if the liquid ; if either
iodide or iodatc is present, a blue zone will appear at the line of
contact of the two liquids. If iodide and iodaie are simultane-
ously present, the .solution of the salt will also afford, on the simple
addition of a few drops of diluted sulphuric acid, a yellow or
brow ni.sh -yellow color, due to the elimination of free iodine, which,
upim agitation with a little carbon bisulphide, will impart to the
latter a violct-rcd color.
SODIUM. 561
lodate may be specially tested for, if desired, by dissolving a little
of the salt in ten times its weight of water, acidulated with diluted
sulphuric acid, adding to the solution a few drops of mucilage of
starch, and subsequently a strip of pure metallic zinc; if iodate be
present, a violet or bluish coloration of the liquid will be produced.
Calcium and maf/nesium salts are indicated in the warm solution
of the salt by a white turbidity on the addition of a solution of
sodium carbonate ; they may be distinguished by adding a little
ammonium chloride and ammonia- water to the dilute solution of
the salt, and testing it with ammonium oxalate for calcium, and,
after filtration, if necessary, by the addition of sodium phosphate
for magnesium.
Metallic impurities will be indicated by a dark coloration or
precipitate, when a solution of the salt, acidulated with hydro-
chloric acid, is saturated with hydrogen sulphide, or after filtra-
tion, if necessary, and neutralization with ammonia- water, by the
subsequent addition of ammonium sulphide.
The proper amount of nitric acid contained in the salt may
readily be determined by igniting it, at a red heat, in a small
porcelain crucible, with an equal weight of concentrated sulphuric
acid, until it ceases to lose weight. One grain of the salt, if per-
fectly pure, will thus afford a residue of sodium sulphate, weigh-
ing 0.835 gram. The determination of the proper amount of
sodium in the salt, when free from potassium, may also readily be
accomplished as follows. About 5 grams of the dry sodium
nitrate, contained in a porcelain capsule, are repeatedly evaporated
with a solution of about 8 grams of oxalic acid to dryness, until
completely converted into sodium oxalate. The latter is then, by
ignition, converted into sodium carbonate, which is dissolved in
water, and, after the addition of a few drops of litmus solution,
titrated with a standard solution of oxalic or sulphuric acid (page
82), as described under sodium carbonate, on page 545. The cal-
culation may then be made with the consideration that one cubic
centimeter of normal acid corresponds to 0.053 gram of sodium
carbonate, or, as its equivalent, 0.085 gram of pure sodium nitrate.
80DII PH08PHA8.
SODIUM 8EU NATRIUM PII09PH0RICUM.
Phosphate of Sodium, Tribanic Sodium Phosphate. Di-iodium Hydrogen
Orttiophotiphate.
Qer. Phospborsanres Natrium ; Fr. Phosphate de Boude ; 8p. Fosfato de sosa.
Na,nP0,+ 12H,0; 358.
Large, colorless, transparent, monoclinic prisms (Fig. 167), con-
taining 12 molecules (60.3 per cent.) of water of crystallization;
3tf
5«2
MASnAL OP CBMICAt ASlLTStS.
tVr rcadilr pffliKCMe aim) bttcomc i
^
; opaqm
•>n expamre to the air, Icvtng ihcrebj, at
coniintm lemperatDnes, 5 molecnles CiH.l per
cent.) of water, and become convened tnUi
a salt iif the curoposition N'a,HP0,+7H,0,
whidi msT also hr obtained fincn Folatiom
of the iirainary silt, in a crv^^tnlline fonn,
at teniperatun^ above ;*3° C. {91.4° F.); on
OBlinocd beating to Hlt>- 0. (212° F.), l)i«
(tall loses the enlire atnoaot (rtO.S per cent.)
of water of rrvstallizalion. When heAled
toab.Kji -10- C".(1"H° F.i,sodiam pho^bate
fimt undergoes aqueons fusion, and after-
ward melu at a red hirat into a limpid gUaa
of sodiam pTn>ph»sphate, which become*
opai{uc nn cooling.
Sodiiiffl phoMphate is aoIoWe in 9 parts of water at 15° C
(59^ F.), and in 2 parts of hi)iling wnter, bdt \» insoluble in alcu-
Itol. Ita B>>tution has u «ooIiit;r, saline taste, a rnintly alkaline reao-
tioQ, afl'ordfl no cfFerTesucence upon the iiddition of an acid, and
^vc8 with 9olQiion of argentic nitrate, a hright-vellow precipitate,
mliible in both ammonia- water and niiric acicf ; the ainmooiacal
nalntion remsinH nnclianged, when the tesi-mbc. wherein it is con-
tAinei], ift immersed in boiling water (distinction from the simitar
argentic amenile, whose ammooiacal solntion deposits metallic sil-
ver upon the walls of the test-tube upon warminid;). With len
magnesium mixture, sodium phosphate givL-s a white cryntalUoo
precipitate, insoluble in an excess of the sail as w>;ll as of the
reagent,
bandnation :
Sodium c'lrl'mnle is detected by effervescence, upon t)ic addition
of li ydr"x;hlori<) aciil to the concentrated solution of the salt,
Sulpiiatts and ehtori/len are delected in tiie diluted solntion,
fltrongly acidulated with nitric acid, when tented in separate por-
tions, with barium chloride for sulphate, and with ar^ntio nitrate
for chloride.
Cataum and ma'piesittm sails will be indicated in the soluticm
by H white precipitate on the addition of ammnnia-water. They
may be dii^tinguislied, by adding to the solution of the salt « few
drops of u solution of amtnoiitum oxalate, when H white precipi-
tate will indicate calcium, and, after filtrntion, if necessary, and
the addition of ammonia-water, an ensuing while, urystHlline pre-
cipitate will reveal the presence of magnesium.
Metnllie Imjiuritie*.— Ahout 20 grains of llie salt are dissolved
in the requisite quantity of water, a few drops of hydrfHihloric
acid added, and the solntitui, after being heated to boiling, is satu-
rated with hydrogen sulpliide; the Husk is tlien oorked and
allowed to stand in a warm place foriiboul twelve houm. A yet-
SODIUM.
563
4AiW
low precipitate would indicate arsenic, a dark one, the presence of
other metallic impurities. The solution, after filtration, if neces-
sary, may be neutralized with ammonia-water, and tested with
ammonium sulphide, when an ensuing dark coloration or precipi-
tate will likewise reveal the presence of metallic impurities.
As a conlirmatory test, or if the presence of other metals
requires a s[)ecial test for arsenic, about lo grams of the sodium
phosphate are dissolved in a little more than an equal weight of
pure, concentrated hydrochloric acid in a wide test tube, the solu-
tion being effected by dipping the tube into hot water and by
agitation; a strip or roll of bright copper-foil is then completely
immersed in the liquid, the tube again dipped into boiling water,
and allowed to stand therein for half an hour. The copper must
remain bright ; a grayish or grayish-black coating of the copper
would be evidence of the presence of arsenic.
Another simple test for arsenic consists in dissolving a little of
the salt in dilute sulphuric acid, in a test-tube, adding thereto a
few fragments of pure metallic zinc, and placing over the mouth
of the tube a disk of white bibulous paper, previously moistened
with a drop of solution of argentic nitrate (Fig. 168);
if arsenic be present, a dark metallic stain will be pro- Fio. 108.
duced upon the paper.
Estimation :
The purity of sodium phosphate may be quantita-
tively determined by dissolving 1 gram of the salt in
about ten times its weight of water, and adding to the
solution test magnesium mixture, until a precipitate
ceases to be produced ; the mixture is then allowed to
stand for several hours, the precipitate collected upon
a filter, washed with a mixture of one part of ammonia-
water and three parts of water, and, after being allowed
to dry, is brought into a weighed porcelain crucible,
and strongly ignited at a red heat. If the salt be pure,
the residue of magnesium pyrophosphate thus obtained
will weigh 0.81 gram, or 100 parts of magnesium pyro-
phosphate correspond to 822.52 parts of crystallized
8t)dium phosphate, NnJTPO^+ 12H,0.
The purity of the salt, in the absence of other sodium
salts, may Jils4> be determined by the estimation of the
amount of contained sixlium. O.o gram o( the salt is
dissolved in a little water, a solution of plumbic acetate
added until a precipitate cejises to be pnKluced, and
sabsequently filtered; the filtrate is then saturated
with hydrogen sulphide, filtered from the precipitate
of plumbic sulphide, and, after acidulation with hvdro-
chloric acid, evaporated to dryness on the water- bath. The residue
of sodium chloride is then brought into a weighed porcelain cru-
cible, dried first at about 110° C. (230° R), and finally gently
564 MANUAL OF CHBMfCAL A9ALT8T8.
ignited, and weighed. From the weight of the residne thus
obtained the amount of phosphate may be calculated: 100 parts
of sodium chloride corresponding to 305.98 parts of crystallized
sodium phosphate, Na,HP0^-Hl2H,0.
80DII PTR0PH08PHA8.
80DIUM 8EU NATRIUM PYROPHOSPHORICUM.
Pyrophoitphate of Sodium. Sodium Pyro' or TetrapkotphaU.
Ger. PyropbosphorMaures NAtrinm ; Fr. Pyrophosphate de soade ;
8p. Pin)fo«fato de sosa.
Na.P^O.+lOHP; 446.
Colorless, transparent, brilliant, monoclinic prisms, or a white
granular powder, containing ten molecules (40.36 per cent.) of
water of crystallization, and permanent in the air ; when exposed
to heat, the salt gives oft' its water of crystallization, without pre-
viously undergoing aqueous fusion (distinction from sodium pnos*
phate), fuses at a higher tem):>erature, and, on cooling, concretes
to a crystalline semi-transparent mass.
Sodium pyrophosphate is soluble in 12 pnrts of water at 15° C.
(oO-' F.), and in l.l parts of boiling water, but is insoluble in
alcohol. Its aqueous solution possesses a saline taste and an
alkaline reaction ; it yields with a slight excess of a neutral solu-
tion of argentic nitrate a white precipitate of argentic pyrophos-
phate, and the filtrate therefrom is neutral in its action upon test-
paper (additional distinction from sodium phosphate).
The solution of sodium pyrophosphate remains unchanged upon
boiling, but if heated after the addition of a little nitric acid, it is
gradually converted into the tribasic phosphate, and then affords
the reactions of the latter, as described on page 562.
Examination :
Sodium phosphate will be indicated, when heated in a small
glass tube, by the fusion of the salt previous to the elimination
of the water; and also by the formation of a yellow precipitate
with a neutral solution of argentic nitrate.
(■arlonafe is detected in the solution of the salt, bv effervescence
upon the addition of a little hydrochloric acid.
Sulphate and chloride may be detected in the diluted solution,
. after strongly acidulating with nitric acid, by white precipitates
when tested in separate portions, with barium nitrate or chloride
for the former, and with argentic nitrate for the latter.
Helallic imj)urities are detected in the warm aqueous solution,
acidulated with hydrochloric acid, by saturation with hydrogen
sulphide, and, after filtration, if necessary, and subsequent neu-
tralization with ammonia; water, by a dark coloration or precipi-
tate with ammonium sulphide.
SODIUM. 565
80DII 8ALICTLA8.
SODIUM 8EU NATRIUM SALICYLICUM.
Salicylate of Sodium, Sodium Salicylate,
Ger. Salicylsaures Natrium ; Fr. Salicylate de soude ; Sp. Salicilato de sosa.
2NaC,H,0,+ H,0 - 2C,n,<g^^_Qjf^+H,0; 338.
Small, white, crystalline plates, with a |)early lustre, or a crys-
talline powder, permanent in the air, and containing, for two
molecules of the salt, one molecule (5.32 per cent.) of water of
crystallization. When strongly heated, the salt becomes decom-
posed, with the evolution of inflammable vapors, and leaves a
residue of sodium carbonate, amounting to between 30 and 81
per cent, of its original weight; this residue possesses a strongly
alkaline reaction, effervesces with acids, and imparts an intense
yellow color to the non-luminous flame.
Sodium salicylate is soluble in 1.5 parts of water and in 6 parts
of alcohol at 15*^ C. (59® F.), and very soluble in boiling water
and boiling alcohol ; it is also freely soluble in glycerin, but very
sparingly soluble in ether. The aqueous solution possesses a sweet-
ish, saline, mildly alkaline taste, and a slight alkaline reaction,
and affords a reddish-brown precipitate on the addition of a solu-
tion of ferric chloride. When the aqueous solution of the salt is
supersaturated with hydrochloric or sulphuric acid, a voluminous
wnite precipitate of salicylic acid is produced, which is readily
soluble in boiling water. crystallizing out upon cooling; it is also
freely soluble in ether, and assumes an intense violet color on the
addition of a few drops of a solution of ferric chloride.
Examination :
The aqueous solution of sodium salicylate should be colorless
and odorless, and its transparency should not be disturbed by the
addition of an equal volume of alcohol.
Carbonates may be recognized in the solution of the salt by
effervescence on the addition of dilute hydrochloric acid.
Chlorides and sulphates may be detected in a solution of 1 part
of the salt in a mixture of 50 parts of alcohol and 25 parts of
water, acidulated with nitric acid, and filtered, by testing it, in
separate portions, with argentic nitrate for chlorides, and with
barium chloride or nitrate for sulphates.
Organic impurities will be indicated by a brown or blackish
coloration, when 1 j)art of the salt is agitated with about 15 parts
of cold concentrated sulphuric acid.
This hook is the proiyevi j
COOPER MEDICAL COLLXO^.
SAN FRANCISCO. GAL
o.vd i> not to he remor^ from i^^ti
566 MANUAL OF CHBMICAL ANALYSIS.
80DII 8ANTONINA8.
SODIUM 8EU NATRIUM 8ANT0NINICUM,
SantoninaU of Sodium. Sodium SantoninaU.
Qer. SantoniDBaureB Nalrium ; Pr. Santoninate de soude ; 8p. Santdninato
de 8<)8a.
2NaC,,H,,0,4-7H,0; 698.
Colorless, transparent, tabular crystals, belonging to the rhom-
bic system, which by exposure to sunlight slowly acquire a yel-
lowish color; they contain, for 2 molecules of the salt, 7 molecules
(18.05 percent.) of water of crystallization, and effloresce slightly
on the surface on exposure to dry air. AVhen heated to 1(H)® C.
(212® F.), the salt loses its water of crystallization, and melts at
142° C. (287.6-' F.), assuming thereby a tine red color, without,
however, undergoing decomposition; at a higher temperature it
chars, with the evolution of inflammable vapors, which burn with
a very smoky flame, and finally leaves a strongly alkaline residue,
which imparts an intense yellow color to the non-luminous flame.
Sodium santoninate is soluble in 8 parts of water and in 12 parts
of alcohol at 15^ C. (59° F.), in 0.5 part of boiling water and in 8.4
parts of boiling alcohol. The aqueous solution possesses a mildly
saline, slightly bitter taste, and a feebly alkaline reaction ; with
diluted acids it yields a white, crystalline precipitate of santoninic
acid, which, however, becomes rapidly converted into santonin, is
readily dissolved by agitation with chloroform or ether, and yields,
with an alcoholic solution of potassium hydrate, a scarlet-red liquid,
which gradually becomes colorless.
Examination :
The cold a(iueous solution of sodium santoninate should be
colorless, should not effervesce on the addition of acids, and should
attbrd no turbidity when mixed with an equal volume of alcohol.
Alkaline earths may be detected in a solution of 1 part of the
salt in 20 parts of water, by a white turbidity or precipitate on
the addition of a solution of sodium carbonate.
Sul/)hatt.'s and chlorides may be detected by dissolving a little of
the salt in an equal weight of warm water, subsequently adding
diluted nitric acid until a precipitate ceases to \>c produced, and,
after titration, testing the liquid, in separate portions, with barium
chloride for sulphates, and with argentic nitrate for chlorides.
Alkaloids^ wliich, by accident, have occasionally been found to
occur in santonin, may be sought for in sodium santoninate by
testing the acidulated aqueous solution of the salt with potassio-
mercuric iodide, iodinized potassium iodide, picric or tannic acids;
no turbidity or precipitate should be produced by either of these
reagents.
SODIUM. 507
80DII SULPHAS.
SODIUM SEU NATRIUM SULPURICUM.
Sulphate of Sodium, Olauber^s Salt. Sodium Sulphate.
Ger. SchwefeUaures Natrium, Qlaul>er8alz ; Fr. Sulfate de soude ; Sp. Sulfato
de sosa.
Na,SO,+ 10H,O; 322.
Large, colorless, transparent, monoclinic prisms (Fig. 169),
having the specific gravity of 1.481, and containing ten molecules
(55.9 per cent.) of water of crystallization ;
they effloresce rapidly on exposure to the air, Fio. 109.
losing all the water of crystallization, and
crumbling to a white powder. When heated
to 33® C. (91.4*^ F.), the salt undergoes aque-
ous fusion, and at a higher temperature loses
its water of crystallization, leaving an an-
hydrous residue, which melts at a red heat
without decomposition. A fragment of the salt imparts an intense
yellow color to the non-luminous flame.
Sodium sulphate is verv soluble in water: 100 parts of water
at 0® C. (32^^ F.) dissolve ''12.17 parts, at 18° C. (64.4^ F.) 48.28
parts, at 25® C. (77® F.) 99.48 parts, and at 33® C. (91.4® F.) 322.12
parts, of the crystallized salt; above that temperature the salt
passes into the anhydrous state, in which it is less soluble, and the
solution then separates the anhydrous salt in the form of small
rhombic octohedrons. The solution saturated at 33® C. (91.4® F.)
affords no crystals upon cooling to the ordinary temperature, but
remains supersaturated; if, however, a fragment of the crystal-
lized salt be added to the solution, it immediately solidifies, accom-
panied by a considerable rise of temperature. The supersaturated
w)lution apparently contains a salt with 7 molecules of water of
crystallization.
Sodium sulphate is also soluble in glycerin, but is insoluble in
alcohol. The aqueous solution of the salt possesses a saline and
feebly bitter taste, is neutral, remains unaltered with sodium car-
bonate as well as with sodium bitartrate, and gives a granular
white precipitate with lime-water, and a copious white one with
solutions of both barium and lead salts, which latter precipitates
are insoluble in diluted acids.
If 1 gram of crystallized sodium sulphate be dissolved in a
little water, the solution acidulated with hydrochloric acid, and
completely precipitated by barium chloride, a precipitate of barium
sulphate is produced, which, when collected u{)on a filter, washed,
dried, and ignited, should weigh 0.723 gram.
Examination :
A solution of one part of the crystallized salt in four parts of
568 MANUAL OF CHIiUICAL ANALYSIS.
water, tested with bhie and with red litmua-paper, should noi
change the color of cither.
Chloride may be delected in the diluted solution, acidulated
with nitric acid, by a white turbidity or precipitate with argentic
nitrate.
Carbanalfi may be detected in the solution of the salt by eB'er-
vescence on the add.tion of an acid.
Ammonium nd/ihale may be recognized by the odor as well as
by the rise of white vapors, when a little of the triturated salt is
heated in a strong solution of potassium hydrate, and a glass rod,
moistened with acetic acid, is held in the orifice of the test-tube.
Ma'jnesitim and calcium sails are detected in the solution by a
white precipitate with sodium carbonate; a reddish or brownish
appearance of the precipitate would inilicate metallic impurities
(iron and manganese); the presence of manifnrifse suits may be
confirmed by a brown precipitate upon the addition of a solution
of chlorinated lime to the solution of the sodium sulphate, that of
iron by a blue turbidity, when the solution of tho salt is acidulatod
with hydrochloric acid and tested with potassium ferrocyaoide.
Metals may further be delected in the diluted solution by add-
ing a little ammonium sulphide, and allowing the mixture to
stand for a few hours; a white turbidity would indi-
Fio. 170. ijate j,'^ and a brownish -blank one. copper; a gre«n-
ish-black one would confirm the presence of iron, and
a pale-reddish one, that at manganese.
If a test for arsenic is required, about 2 grams of the
crystallized sodium sulphate are dissolved in au equal
weight of warm waicr in a wide test-tube ; an amount
of concentrated hydrochloric acid equal to about tan
times the weight of the salt is then added, and a atrip
or roll of bright copper-foil completely immersed in
the fluid ; the tube is then dipped into boiling water
and allowed to stand in the water for half an hour. The
copper must remain bright; a grayish-black costing
would indicate arsenic. The presence of arsenic may
also readily be determined by adding to a solutiou of
the salt, in a test-tube, a strong solution of potassium
hydrate, subsequently a few fragments of pure metal-
lic zinc, and placing over the mouth of the tube a cap
of bibulous pajier moistened with a drop of a solution
of argentic nitrate (Fig. 170), aud gently beating; if
arsenic be present, a dark metallic stain will be pro-
duced on the paper.
iSulphite and hyposulphile may be detected in a solu-
tion of one part of the salt in three parts of water, by
mixing it, in a test-tube, with one-fchird of its volume of
concentrated hydrochloric acid, and heating it gently with a few
fragmenu of granular zinc; the presence of c.ther of the above salts
SODIUM. 569
will give rise to the formation of hydrogen sulphide, which may be
recognized by placing a small bunch of cotton, moistened with solu-
tion of plumbic acetate, in the orifice of the tube, or by closing it
with bibulous ]:>aper moistened with the plumbic solution (Fig. 170).
A black coloration of the cotton or a dark stain upon the paper
would indicate the presence of either or both of the above salts.
SODII SULPHIS.
SODIUM SEU NATRIUM 8ULFUR0SUM.
Sulphite of Sodium, Sodium Sulphite.
Ger. Schwefligsaures Natrium ; Fr. Sulfite de soude ; Sp. Sulflto de Bosa.
Na^SOa + TH^O; 252.
Colorless, transparent, monoclinic prisms, containing seven mole-
cules (50 per cent.) of water of crystallization ; on exposure to the
air, they effloresce somewhat, and the salt is gradually converted
into sulphate, emitting a feeble odor of sulphur dioxide. This
liability to decomposition is retarded, and the salt made more per-
manent, by exsiccating it at a gentle lieat, when it undergoes aque-
ous fusion, loses its water of crystallization, and becomes white.
It is this granular form in which sixlium sulphite is now frequently
met with. When this salt is exposed to a strong red heat, it fuses
to a dirty yellowish mass, consisting of sodium sulphate and sul-
phide; these may be separated by extracting the cold residue
with strong alcohol, which dissolves the sulphide, but not the
sulphate.
Crystallized sodium sulphite is soluble in 4 parts of water at
16° C. (59^ F.), and in 0.9 part of boiling water, but only spar-
ingly in alcohol; its aqueous solution has a feeble alkaline reac-
tion, and becomes turbid upon heating, but transparent again on
cooling; on exposure of the solution to the air, the sulphite is
gradually converted into sulphate with the separation of sulphur,
as it is also by treatment with oxidizing agents, such as chlorine,
hypochlorous acid, nitrous acid, etc. When acidulated, solution
of sodium sulphite acts as a powerful reducing agent ; it emit5
sulphur dioxide upon the addition of strong acids, slowly when
cold, freely on warming, and, in the latter instance, with the sepa-
ration of sulphur; when this test is i)erformed with hydrochloric
or sulphuric acid, and with the addition of a little zinc, hydrogen
sulphide is evolved. With barium chloride or nitrate, solution
of sodium sulphite forms white precipitates, soluble in diluted
hydrochloric acid.
Examination:
Sodium sulphate may be detected in a solution of 1 part of the
salt in 100 parts of water, strongly acidulated with hydrochloric
570 MANUAL OF CHBMICAL ANALYSIS.
acid, by a white precipitate oa the addition of a few drops of solu-
tion of barium chloride.
Estimation:
About 0.5 gram of the salt is dissolved in a small portion of
water, a little mucilage of starch added, and subsequently a deci-
normal solution of iodine (page 93) allowed to flow into the liquid
from a burette until, with constant stirring, a ^)ermanent blue
coloration of the liquid is just produced. The number of cubic
centimeters of iodine solution, which are required to produce this
reliction, when multiplied by the decimal 0.0126, will represent
the amount of pure, crystallized sodium sulphite in the specimen
under examination, and therefrom its percentage purity may readily
be calculated.
The United States Pharmacopoeia directs that if 0.63 gram of
the salt be dissolved in 25 cubic centimeters of water, and a little
gelatinized starch added, at least 45 cubic centimeters of the volu-
metric solution of iodine should be required, before a permanent
blue tint appears after stirring (corresponding to at least 90 per
cent, of pure sodium sulphite).
80DII SULPHOCARBOLAS.
SODIUM 8EU NATRIUM 8ULF0CARB0LICUM 8EU
8ULF0PHEN0LICUM.
Sulphocarholate of Sodium, Sodium Sulphocarholate or SulphophenolaU.
Ger. Plienolsulfosaures Natrium ; Fr. Sulfocarbolate de soode ;
Sp. Sulfocarbdlato de sosa.
NaC JI,.SO, + 2 H,0 = '^o^^^XsO^-O^^ + 2 H.0 ; 232.
Colorless, transparent, rhombic prisms, containing two mole-
cules (lo.ol per cent.) of water of crystallization, and permanent
in the air. When heated to 100^ C.^(212° F.), the salt loses its
water of crystallization, and becomes converted into a white pow-
der ; at a higher temperature it is decomposed, with the evolution
of inflammable vapors, having the odor of phen()l (carbolic acid),
and leaving a white residue, amounting to S6 per cent, of the
original weight ; if this residue be dissolved in water, the solution
filtered, acidulated with hydrochloric acid, and tested with a few
drops of solution of barium chloride, a white precipitate of barium
sulphate will be produced, insoluble in nitric or hydrochloric
acid. A fragment of the salt, when heated in the non-luminous
flame, imparts to the latter an intense yellow color.
Sodium sulphocarholate is soluble in 5 parts of water and in
132 parts of alcohol at 15^ C. (59^ F.), in 0.7 part of boiling water
BPIRITUS. 571
and in 10 parts of boiling alcohol. The aqueous solution pos-
sesses a cooling, saline, slightly bitter taste, and is neutral in its
action upon litmus; it yields, even when highly diluted, a deep
violet color on the addition of a few drops of a solution of ferric
chloride.
Examination:
Sulphate may be detected in a solution of 1 ])art of the salt in
100 parts of water by an immediate white turbidity or precipitate
on the addition of a solution of barium chloride.
Baritim and calcium salts may be detected in the aqueous solu-
tion, when tested in separate portions, with magnesium sulphate
for the former, and with ammonium oxalate for the latter.
Metallic impurities will be indicated in the solution of the salt,
either before or after acidulation with hydrochloric acid, by a
turbidity or precipitate when saturated with hydrogen sulphide;
the occurrence of a white precipitate with the latter reagent in
the neutral solution of the salt would indicate the presence of zinc.
BPIRITUS 2ITHBRI8 NITR08I.
SPIRITUS NITROSO-^THEREUS. SPIRITUS NITRI DULCIS.
Spirit of Nitrou9 Ether. Sweet Spirit of Nitre. Alcoholic Solution of
Ethyl Nitrite.
Oer. Versusster Salpeterj^eist ; Fr. Ether azoteux alcoolisc ;
Kp. Enpfritu dc iiitro dulcc.
A colorless or pale-yellow, volatile liquid, of a fragrant, ethe-
real odor, and sharp, aromatic, sweetish taste ; its spec. grav. is
0.823 to 0.825 U. S. Pharm. (0.845 Brit. Pharm., and 0.840-0.850
Pharm. Germ.), and it should contain between 4 and 5 percent, of
ethyl nitrite. It is inflammable, reddens blue litmus-paper not
at all or only faintly, and assumes a dark color up(m the addition
of a few drops of a solution of ferrous chloride or sulphate.
When added to a dilute solution of potassium iodide, to which a
few drops of d.lute sulphuric acid and a little mucilage of starch
have previously been added, a blue ct)loration will be produced.
Spirit of nitrous ether is miscible with water, alcohol, chloro-
form, ether, carbon bisulphide, benzol, and essential and fatty
oils. A portion of the spirit, in a test-tube half filled with it,
plunged into water heated to 68^ C. (145.4^ F.), and held there
until it has acquired that temperature, will boil distinctly on the
addition of a few small pieces of glass.
Examination :
Aldehyde is indicated by a brown coloration of the spirit when
agitated in a test-tube with a few fragments of fused potassium
hydrate.
572
HANDAL OF CHBHICAL AMALTSIS.
Acids, — Spirit of nitrous ether containing so much of free acid
us to have a pcrceptihle sour taste and an acid reaction upon blue
litmus-paper, and to cause tbe rise of gas-biibbles from a few
crystals of potassium bicarbonate when dropped into it, cannot be
considered admissible for medicinal use.
£lhyl chloride may be detected by burning away a small quan-
tity of the spirit upon a Httle water in a porcelain capsule, and
by subsequently testing the water, after acidutation with a few
drops of nitric acid, with a few drops of solution of argentic ni-
trate ; the occurrence of a white turbidity would indicate the
presence of ethyl chloriile,
Methylic Alcohol. — About 30 cubic centimeters of the spirit are
shaken with 2 to 3 grams of anhydrous (exsiccated) potassium
carbonate; after subsiding, the supernatant spirit is decanted;
about 15 cubic centimeters of this dehydrated spirit is introduced
into a small flask, or a test-tube of a proper size (Fig. 171), 10
Fio. 171.
gramsof anhydrous caluum chloride in powder are added, and, after
thoroughly mixing, the flask is connected with a bent glass tube or
a condenser, and is tlien placed in a water-bath for distillation ; this
distillation iwconliniicd until about 5 cubic centimeters of distillate
have been obtained. The tcst-lubi- is then removed from the water-
bath, and, wlieii cool, 5 cubic centimeters of water arc added, and
the distillation once more resumed until a little more than 2 cubiu
centimeters of distillate are obtained. The latter distillate is mixed
with 15 cubic centimeters of water, wherein 2 grams of potassium
bichromate and 30 drops of concentrated sulphur.cacid have been
dissolved. After having allowed the mixture to stand for a quarter
of an hour, it also is submitted to distillation, until 15 cubic cen-
timeters of distillate are obtained; to this 2 grams of crystallized
.•iodium carbonate are added, in a porcelain capsule, and the whole
8PIRITU8. 578
evaporated to half its volume ; it is then slightly supersaturated
with acetic acid, filtered into a test-tube, and about 30 drops ot
solution of argentic nitrate added, and the whole gently boiled for
about two minutes. If the spirit is free from methylic alcohol,
the solution darkens, and often assumes transiently a purplish
tinge, but continues quite transparent, and the test-tube, after
being rinsed out and filled with water, appears clean. But, if
the spirit contains even traces of methylic alcohol, the liquid
becomes at first brown, then almost black and opaque, and a film
of silver is deposited on the tube, which api)ears brown by trans-
mitted light. When only 3 to 4 per cent, of methylic alcohol is
present, the film is sufficiently thick to form a brilliant metallic
mirror.
Estimation of the Quantity of Ethyl Nitrite :
Ten grams of the spirit of nitrous ether are digested in a strong
glass-stoppered vial for about half an hour, on the water- bath,
with about three times its volume of an alcoholic solution of pure
potassium hydrate. The ethereal odor will then have disappeared,
and the contents of the vial are transferred to a beaker, a little
water added, and gently heated on the water-bath until the alco-
hol has evaporated. The remaining solution is then diluted to
the measure of about 200 cubic centimeters, acidulated with
dilute sulphuric acid, and a decinormal solution of potassium per-
manganate (page 89) allowed to flow into the liquid from a burette
until, with constant stirring, the red color imparted to the liquid
ceases to be discharged within a few minutes.
The exact strength of the potassium permanganate solution
having been previously determined by means of metallic iron, as
described on page 89, the amount of potassium permanganate,
expressed in grams, contained in the volume of the solution em-
ployed, may readily he calculated; this number, when multiplied
by 1.18, will represent the amount of pure ethyl nitrite in 10
grams of the spirit, and requires simply to be multiplied by 10 in
order to express the percentage.
The reactions involved in the above operation may be repre-
sented by the following equations:
(a) 5C,H.-NO,+5KOII = 5C,H,-OII-i-oKNO,
375
(^) 5KNO,+3II,SO,+K,Mn,0=5KNO,-hK,SO,-h2MnSO,+3U,0.
*- _ J •
Y
316
Therefore ||f =1.18, and accordingly a:K,Mn30,Xl.l8=a;C,K,-NO,
The United States Pharmacopoeia directs that if 10 grams of
spirit of nitrous ether be macerated with 1.5 grams of potassium
hydrate for twelve hours, with occasional agitation, the mixture
then diluted in a beaker with an equal volume of water, and set
574
MIAL OP CHBHICAL ANALYSIS.
aHide until the odor of alcohol has disappeared, then slightly acidu-
lated with diluted sulphuric acid, and a solution of 0,835 gram of
potassium percnanganate gradually added, the color of the whole
of this sohitiou should be discharged (corresjjonding to the pres-
piice of at least 4 ]>er cent, of pure ethyl nitrite).
STRTCBNIIIA.
STRYCHNINUM. STRYCHNIUM.
Oer. 8tryclii
Hri/cha{nt. Blrsehnia.
n ; Fr. Strychnine ; Sp. EsrTicninB.
C„Q.,N,0,: 334.
Small, brilliant, octaiiedral crystals, or four-sided prisms of the
rhombic system, colorless and transparent, or a white, crystalline
powder, pennunciit in the air. When the crystals are very care-
i'liily heated, in small amount, they melt without decom position,
and tnay also to a slight extent be sublimed ; when heated upon
])latinuin-f(>il, tlicy spread over the foil like melted resin and
lK;ci)medec.;mjKised, leaving a charred residue, which, at a stronger
iiciit, is wholly dissipated (evidence of the absence of fixed ad-
mixtures).
Strychnine is soluble in 6700 parts of water and in 110 parts of
alcohol at U>° 0. (i"i!t° F.); in 2500 parts of boiling water and i[i
VI parts .)f liiiiliiiii alcohol. It is also soluble in *> |mris of chloro-
form, 170 parts of benzol, 185 parts of
Fir,. 172. amy lie alcohol, 300 parts of glycerin, and
485 parts of carbon bisulphide, but is
almost insoluble in ether, absolute alci>-
hoi, and petroleum bcnzin ; dilute acidn
dissolve it freely and without color. The
saturated alcoholic or aqueous solution
possesses an alkaline reaction and an
intensely bitter taste, which is atill per-
ciiptibic when diluted to such an extent
that 700,000 parts of the solution con-
tain but 1 part of the alkaloid.
When a few drops of cold concen
trated nitric acid are added, by means ol'
a glass rod or a .tniall pipette (Fig. 172),
to a little strychnine, or its .sails, on a
watch-glass or porcelain plate, it dis-
solves without any color, or with only a
pale-greenish or yellow tint (distinction
irom brucine and morphine, and their
8TRYCHNINA. 575
salts, which give intensely red solutions). Strong sulphuric acid
also dissolves strychnine and its salts without color (distinction
from brucine, veratrine, and salicin, which yield red or purple
colorations); but, when a minute fragment of a crystal or one
drop of a solution of potassium bichromate or permanganate is
added, the solution assumes at once a deep-violet or blue color,
which successively changes from violet to red, and linally to green
or yellow.*
When a cold, saturated alcoholic solution of strychnine is mixed
with about an equal volume of an alcoholic solution of ammonium
sulphide, and the mixture is allowed to stand for twelve hours, long,
brilliant, orange- red needles arc formed, having the composition
(C,.H„NjO,),S^II„ which are insoluble in water, alcohol, ether,
ana carbon bisul|)hide, and are decolorized and decomposed when
treated with concentrated sulphuric acid, with the formation of
strychnine sulphate, and of an oily compound of a penetrating
odor, which, in c(mtact with water, is resolved into sulphur and
hydrogen sulphide. Strychnine only is known to produce this
reaction.
When a little strvchnino is ajritated with a small amount of
warm water, insuflRcient to dissolve it. it will dissolve readily upon
the subsequent addition of a few drops of diluted sulphuric acid;
this solution, wiien tested in separate portions, will yield ])recipi-
tates with tannic acid, with potassio-mercuric iodide, and with
iodinized potassium icxlide; it will remain unaltered with potas-
sium bicarb<mate (distinction from the cinchona alkaloids), but it
will yield a white ])rccipitate with the alkaline hydrates, insoluble
in an excess of the precipitant (further distinction from mor-
phine), and also but sparingly soluble when agitated with ether,
out readily soluble in chloroform.
Examiiiation :
Incidental or fraudulent admixtures of other alkaloids arc recog-
nized by the above-described characteristics and reactions of
strychnine.
Brucine and anlicm are indicated by a red coloration with either
concentrated nitric or sulphuric acid.
Brucine may also be recognized by its ready solubility in abso-
lute alcohol (wherein strychnine is almost insoluble), and by the
reaction of its solution in nitric acid with stannous chloride or
ammonium sulphide (page 283). While pure strychnine affords
a pale-green or yellowish solution with strong nitric acid, this will
appear more or less red, if brucine be present, and will assume,
after the addition of a little water and evaporation of the excess
of acid, a deep violet color upon the subsequent addition of solu-
* Only aniline nnd its snits nre known to nfford, with the sflme reagent, a
similar reaction, ^vhich, however, is less of n violet and more of a blue tint
throngbout, and >\hich does not app<ar immediately.
576 MANUAL OF CHEMICAL ANALYSIS.
tion of stannous chloride, or ammonium sulphide ; if the latter
reagent has been employed, a white turbidity from the separation
of sulphur may occur.
Santonin is recognized by its insolubility in dilute acids, and
by its property of assuming a lemon -yellow color when the sam-
ple, covered with a sheet of thin white paper, is exposed to solar
light for one or two days.
Cinchona alkaloids may be detected by a white precipitate, when
a solution of the strychnine in dilute sulphuric acid is tested with
solution of potassium bicarbonate.
Cinchonine may also be recognized by its insolubility in chloro-
form, remaining behind when a little powdered strychnine is
exhausted with that solvent; its identity may then be ascertained
by its properties, described on page 316.
For the separation of strychnine from other alkaloids with which
it may be associated, or from complex organic mixtures, advan-
tage may be taken of the sparing solubility of the crystalline
chromate or picrate, as precipitated by a solution of potassium
bichromate or picric acid, or the method described on page 108
may be employed. The chromate is specially adapted for obtain-
ing its most characteristic reaction, which is produced by simple
contact of the latter salt with a few drops of concentrated sulphu-
ric acid. The picrate, although a yellow salt, forms a colorless
solution with concentrated sulphuric acid, and is likewise admira-
bly adapted for obtaining the reaction with potassium bichromate.
8TR7CHNIN21 NITRA8.
STRYCHNINUM SEU 8TRYCHNIUM NITRICUM.
If Urate of Strychnine or Strychnia, Strychnine Nitrate,
Ger. Salpetcrsaures Strychnin; Fr. Azotate de strychnine ;
Sp. Nilralo de estricnina.
C„H„N,0,.nN03; 897.
Colorless, transparent, flexible needles, of a silky lustre, perma-
nent in the air. When gently heated on platinum-foil they assume
at first a yellowish color, and, at a higher temperature, deflagrate
slightly, leaving a carbonaceous residue, which, at a red heat, is
wholly dissipated (evidence of the absence of fixed admixtures).
Strychnine nitrate is soluble in 90 parts of water and in 70
parts of alcohol at 15® C. (59^ F.), in 3 parts of boiling water and
5 parts of boiling alcohol, but insoluble in ether and carbon bisul-
phide. Its solutions are neutral, and have an intensely bitter taste.
They yield, on the addition of solution of potassium hydrate, a white
STRYCUNINA. 577
precipitate of strychnine, which is insoluble in an excess of the
precipitant.
Strychnine nitrat^j answers to all the reactions of strychnine,
and may be recognized by the characteristic coloration with strong
sulphuric acid and potassium bichromate or permanganate, as
described on page 575. In distinction from strychnine, it is fur-
thermore specially cliaracterized by heating a crystal of the salt, or
a little of tlie solution with concentrated hydrochloric acid, to boil-
ing, when a bright red color is produced. The evidence of being
a nitrate is not readily obtained by the direct application of the
ordinary tests, and in performing this reaction the strychnine
should first be precipitated from the solution of the salt by the
addition of a slight excess of potassium or sodium hydrate; the
filtrate may then be tested by supersaturating it with hydrochloric
acid, adding a drop of solution of indigo, and heating to boiling,
when decoloration of the liquid will ensue ; or, to the filtrate, con-
centrated sulphuric acid, in slight excess, may be added, and sub-
sequently a saturated solution of ferrous sulphate allowed to flow
upon the surface of the liquid by means of a pipette, so as to form
two layers (Fig. 173) ; a dark-brown coloration will take place at
the junction of the two liquids.
Fio. 178.
The methods for testing the purity of strychnine nitrate are the
same as described with strychnine on pages 575, 576. It needs
only to be added that the salt should not emit ammoniacal odors,
when heated with a strong solution of potassium h3'drate, nor,
upon heating with the latter, should it cause the rise of white
vapors, when a glass rod, moistened with acetic acid, is held over
the orifice of the test-tube.
37
578 MANUAL OF CHBMICAL ANALYSIS.
8TKYCIIMNUM SKU STKVCHNIUM 8ULFURICUM.
Sulphate of Strychnitie or Strychnia, Strychnine Sulphate.
Ger. Bchwefelsaures Strj'chnin ; Fr. Sulfate de strychnine ; Sp. Salfato
de estricnina.
(C„n„N,0,),.H^0,4- 6H,0 ; 874.
Fine, colorless, and transparent prismatic crystals, containing
six molecules (12.24 per cent.) of water of crystallization, and
slightly efflorescent on exposure to dry air. When heated to
about 18»0° C. (tJOo® F.) they lose the water of crystallization,
without previously fusing; at a higher temperature they become
charred and decomposed, and, at a red heat, they burn away with-
out residue (evidence of the absence of fixed admixtures).
Strychnine sulphate is soluble in 42 parts of water and in 60
j)arts of alcohol at 15° C. (59° F.), in 2 parts of boiling water and
in 2 parts of boiling alcohol. It is also soluble in 26 parts of
glycerin, but is insoluble in ether. Its solutions are intensely
bitter; tlieir de])ortment with reagents answers to that of strych-
nine, and they also affc^rd the characteristic reaction with sul-
phuric acid and potassium bichromate or permanganate; the
evidence of being a sulphate may be obtained by the white pre-
cipitate, insoluble in hydrochloric acid, which barium nitrate
yields with a solution of strychnine sulphate in dilute nitric acid.
The solution of the salt yields on the addition of solution of potas-
sium hydrate a white precipitate of strychnine, which is insoluble
in an excess of the precipitant. When heated with solution of
potassium hydrate, the salt should not emit ammoniacal odors,
nor should it cause the rise of white vapors when a glass rod,
moistened with acetic acid, is held over the orifice of the test-
tul)e.
Tlie iniritv of the salt may be ascertained bv the same tests as
described with pure strychnine, on pages 575, 576.
SULPHUR PR2BCIPITATUM.
LAC SULFURIS.
Precipitated Sulpliur, Lac Sulphur,
(tor. Gefiillter Scbwcfol, Scbwefclmilch ; Fr. Soufre pr^cipitd;
Sp. Azufre precipitado.
S; 82.
A fine, slightly coherent powder, of a pale yellowish or grayish
color, without taste or smell, and free Irom grittiness, consisting,
when seen under the mierosco{)e, of minute, opaque globules,
without any admixture of crystalline matter. When thrown
SULPHUR. 579
upon burning coal, or heated in an open vessel, precipitated sul-
pnur first emits a little hydrogen sulphide, then fuses, and burns
wholly away at a stronger heat.
Precipitated sulphur is insoluble in the common solvents, but
is readily and wholly soluble in carbon bisulphide, and in strong,
boiling solutions of potassium and sodium hydrates, and also more
or less in benzol, in hot oil of turpentine, and other essential and
fatty oils.
Examination :
Fixed admixtures are indicated by a white ash or a non-volatile
residue when a small portion of the sulphur is strongly heated in
an open porcelain crucible.
Calcium Sulphate, — A small portion of the sulphur is triturated
with about ten times its weight of tepid water, and the mixture
agitated for a few minutes until cold, when it is filtered; the fil-
trate must not act upon test-paper, as an acid reaction would
indicate long exposure to the air; nor must it leave any residue
upon evaporation upon a watch-glass, which would indicate either
insufficient washing, or an admixture of a soluble fixed compound ;
a white precipitate of the filtrate, when tested with ammonium
oxalate in one portion, and with a few drops of nitric acid and
barium nitrate in another portion, would indicate calcium sul-
phate.
Earthy Carbonates or Pfiosphates.— When the sulphur leaves a
residue on incineration, or oii solution in carbon bisulphide, a
small portion of it is digested for several hours, with occasional
agitation, with about ten times its weight of a mixture consisting
of equal parts of concentrated hydrochloric acid and water; effer-
vescence upon the addition of the acid would indicate the presence
of carbonates. The mixture is then filtered, and one portion of
the filtrate supersaturated with stxlium carbonate; an ensuing
white precipitate would indicate the presence of the above ad-
mixtures; the other portion is heate<l with a few drops of solution
of ammonium molybdate; a yellow coloration of the liquid, and,
after a while, a yellow crystalline deposit, would indicate j)hos-
phates (if the sulphur be free from arsenic).
Any admixture, except jyowdered resin or pitch, which are recog-
nized by a sooty flame when ignited, and V)y their solubility in
strong alcohol or ether, may be quantitativel}' determined by re-
maining undissolved upon digesting a known quantity of the
sulphur with carbon bisulphide, or, when calcium sulphate is the
onl}' admixture, by complete incineration of a weighed quantity
of the sulphur in a tared porcelain crucible; the weight of the
remaining anhydrous calcium sulphate, with one-fourth thereof
added to compensate for the loss of the water of crystallization,
gives the amount of crystalline calcium sulphate present in the
quantity of sulphur under examination.
Arsenic may be detected by triturating a portion of the sulphur
580
MANUAL OF CHEMICAL ANALYSIS
with about ten times its weight of ammonia-water or a saturated
solution of ammonium carbonate, and subsequently digesting the
mixture in a corked test-tube, for about one hour, with occasional
agitation ; the liquid is then filtered, and a portion of the filtrate
supersaturated with hydrochloric acid ; the formation of a yellow
f)recipitate, either at once or upon subsequent saturation of the
iquid with hydrogen sulphide, would indicate arsenic; the rest
of the filtrate is evaporated to dryness in a small porcelain cap-
sule; if a residue remains, it is detached by triturating it with a
little powdered magnesite, or pumice-stone, a little potassium
cyanide is then added, and the mixture, after being introduced
into a reduction-tube (Fig. 174), is first gently heated in order
Fig. 174.
to expel moisture, which may be removed by means of a strip of
bibulous paper, and the contents of the tube subsequently strongly
heated; whereupon, the formation of a metallic mirror and the
evolution of a garlic-like odor would further indicate arsenic.
An admixture of starch may be recognized by examination of
the precipitated sulphur under the microscope, or by boiling a
small portion of it with about ten times its weight of water, and
testing the cooled liquid with one drop of solution of iodinis^ed
potassium iodide. The occurrence of a blue coloration would show
such an adulteration.
SULPHUR. 581
SULPHUR 8UBLIMATUM.
FLORES SULFURIS.
Sublimed Sulphur. Flowers of SiilpJiur.
Ger. Sublimirter Schwofel, Schwefelblumeu ; Fr. Soufre sublime ;
Sp. Azufre sublimado.
S; 32.
A gritty, yellow, tasteless, and odorless powder, consisting,
when seen under the microscope, of a mixture of minute, smooth
§ lobules, and of rhombic-octahedral crystals. When heated in a
ry tube, sulphur fuses at 115° C. (239° F.), forming an amber-
colored fluid, which, when heated to from 220 to 250° C. (428 to
482° F.), becomes more and more thick and tenacious, and as-
sumes a deep brownish-red color; at a temperature approabhing
the boiling-point,. 448° C. (818° F.), it becomes thin and liquid
again, and volatilizes in colorless vapors, which condense on cool-
ing; when heated with free access of air, sulphur takes fire at
about 270^ C. (518° F.), and slowly burns away with a pale-blue
flame, forming sulphurous-acid gas.
Sublimed sulphur is insoluble in water, and almost insoluble
in alcohol and in ether; it dissolves to some extent in chloro-
form, and for the most part in carbon bisulphide,* in benzol, and
in warm or boiling essential and fatty oils; it is wholly soluble
in a hot concentrated solution of potassium or sodium hydrate.
Commercial sublimed sulphur has generally an acid reaction
upon moist test-paper, and contains traces of oxygen acids of sul-
pnur, occasionally also of selenium, and frequently of sulphides
of arsenic, all which impurities have to be eliminated from such
sulphur as is intended for medicinal use (Sulphur lotum, Sul-
phur depuratum) ; this is effected by digesting the crude sub-
limed sulphur for a few days with very dilute ammonia- water, or
with a solution of ammonium carbonate, and by subsequent tho-
rough washing with water, and drying.
lamination :
Washed sulphur should not redden moist blue litmus-paper,
nor aflect the color of water which has been slightly blued with
litmus- tincture, when agitated with a little of the sulphur. Warm
* Both the amorphous (spec. grav. 1.95) and the monoelinic (spec. grav.
1.96, fasing-point 120o C, 2480 P.) modifications of sulphur are almost insolu-
ble in carbon bisulphide, wliile tlie rhombic form (spec. grav. 2.05, fusing-
point 1150 C, 2390 P.) is readily soluble therein. Both the former varieties
pass into the rhombic form, slowly at ordinary temperatures, and more rapidly
at higher ones. Therefore, the older sublimed sulphur is, the more soluble it
is in carbon bisulphide.
There are, however, minor varieties of both the amorphous and the crystal-
line modifications of sulphur, which appear to differ in their deportment with
solvents, and thereby also to alter the solubility of sublimed sulphur in carbon
bisulphide.
582 MANUAL OF CHBMICAL ANALYSIS.
water, when rubbed with the sulphur in a mortar, should yield a
filtrate which leaves no residue upon evaporation on platinum-foil
or on a watch-glass.
Mineral and fixed admixtures are recognized by a non- volatile
residue, either upon complete dissipation of the sulphur in a por-
celain crucible, or upon diss<^lving a small portion of the sulphur
in a strong boiling solution of pc^tassium or sodium hydrate.
Arsenic may be detected b^' digesting the sublimed sulphur for
several hours, with about four times its weight of a concentrated
solution of ammonium carbonate. This dissolves only the arsenic
sulphides or arsenious acid ; the former may be recognized by a
yellow precipitate, either at once or after a while, when a portion
of the filtrate is supersaturated with hydrochloric acid, and by a
yellow res due upon evaporation of the filtrate on a water-bath,
as also by the formation of a metallic mirror when this residue is
heated in a dry reduction-tube with potassium cyanide (Fig. 174,
page 580); the arsenic present in the form of arsenious acid may
oe detected in a portion of the above obtained acid filtrate by the
formation of a yellow precipitate upon saturation with hydrogen
sulphide.
Selenium may be detected by heating to boiling a mixture con-
sisting of about two parts of the sulphur, and a solution of one
part of potassium cyanide in twenty parts of water; when cool,
this mixture is filtered, and the filtrate sup<^rsatu rated with con-
centrated hydrochloric ucid — taking care not to inhale the vapors
of the evolved hvdrocvanic acid ; the solution is allowed to stand
in a (K)rked vial for about twentv-four hours. A reddish tur-
bidity or deposit would indicate selenium. If the sulphur con-
tains arsenic sulphides, they will give rise to the simultaneous
fbrniatioii of a yellow precipitate, which, however, will appear
more or less reddish in hue when selenium is contained in the
sulphur.
Another metliod consists in digesting the sulphur with a neu-
tral, saturated solution of potassium sulphite; the liquid is then
filtered, and subsecjuently supersaturated with hydrochloric acid,
when, if selenium be jjresent, a ilocculeut precipitate of a reddish
color will be produced. The precipitate, after drying, may be fur-
ther tested for its identity, if required, by the development of the
characteristic and exceo<.lingly unpleasant odor upon heating.
This hook is the prcypertj
COOPER MEDICAL COLLXG^,
SAN FRANCISCO. OAL.
arid is not to lie rernm^^d from th
V
9
THYMOL. t58
SULPHURIS lODIDUM.
SULFUR lODIDUM. SULFUR lODATUM.
Iodide of Sulphur, Sulphur Iodide.
Ger. Jodschwefel ; Fr. lodure de soufre ; Sp. loduro de azufre.
A grayish-black solid, usually occurring in pieces of a radiated
crystalline appearance externally, and having the characteristic
odor of iodine, a slightly acid taste, and a faintly acid reaction.
Sulphur iodide is an unstable compound, and is readily decom-
posed; on exposure to the air it gradually loses iodine; it is also
decomposed by boiling water with the volatilization of the iodine,
and, when heated in the air, the iodine passes off in vapor, and is
wholly expelled, leaving a residue of sulphur, which burns away
at a strong heat with a pale blue flame.
Sulphur iodide is insoluble in water, but this takes up a trace
of iodine ; it is soluble in carbon bisulphide and also in about 60
parts of glycerin ; alcohol and ether, as well as strong solutions of
potassium iodide, or of potassium hydrate, deprive it completely
of the iodine, leaving the sulphur behind : in this way, sulphur
iodide may be examined, by exhausting 50 parts of it with alco-
hol, when only 10 parts of sulphur should remain behind; and,
when this is divided into two portions, one of them should burn
away at a strong heat, with the odor of sulphurous acid, and the
other must be completely soluble in carbon bisulphide.
TH7MOL.
THYMOLUM.
Thymol, MethyUpropyl-pJienol.
Ger. Thymol ; Fr. Thymol ; Sp. Timol.
C,,n,,0 = CeH,(C,II,; 150.
\0H
Large, transparent, colorless crystals, belonging to the hexago-
nal system, having an aromatic thyme-like odor, a pungent,
aromatic taste, and neutral in their action npon litmus. In the
crvstalline condition thymol has the specific gravity of 1.028, but,
when liquefied, it is lighter than water and swims upon the sur-
face; it melts at from 50 to 52^ C. (122 to 125.6^ F.), remaining
liquid at lower temperatures, and boils at from 228 to 230^ C.
(442.4 to 446° F.); at the temperature of the water-bath, or
when heated on platinum-foil, it is rapidly volatilized, leaving no
residue.
584 MANUAL OF CHEMICAL ANALYSIS.
Thymol is soluble in about 1200 parts of water at 15^ C.
(59° F.), and in 900 parts of boiling water; in 1.5 parts of alcohol,
in 120 parts of glycerin, and very freely soluble in ether, chloro-
form, carbon bisulphide, benzol, benzin, glacial acetic acid, the
fixed and volatile oils, and solutions of potassium and sodium
hydrate, especially upon warming; it forms a colorless, syrupy
liquid when triturated with an equal weight of camphor. The
aqueous and alcoholic solutions are neutral in their action upon
litmus, and afford no coloration on the addition of a few drops of
solution of ferric chloride (distinction from and absence of car-
bolic acid).
If thymol be dissolved in about half its weight of glacial acetic
acid, an equal volume of sulphuric acid subsequently added, and
the mixture gently warmed, a beautiful reddish -violet color is
produced, which is very permanent, and is not destroyed by an
excess of acid or by boiling.
When fused thymol is gradually mixed with an equal volume
of concentrated sulphuric acid, and the mixture maintained at
a temperature of 60^ C. (140° F.) for about one hour, it solidi-
fies on cooling to a crystalline mass of thyniol-sulphonic acid,
f SO,H
I OH
CgHj -i pTT . If this be dissolved in water, and the solution sub-
i^A ... . ,
sequently poured into ten times its volume of water, and digested
with an excess of lead or barium carbonate, and filtered, the fil-
trate will assume, on the addition of a trace of ferric chloride, a
beautiful violet-blue color.
VERATRINA.
VERATRINUM. VEHATRIUM.
Veratrine. Ver atria.
Ger. Veratrin ; Fr. Veratrine ; Sp. Veratrina.
A white or grayish-white, coherent powder, or, more rarely,
minute, efllorescent, prismatic crystals, without smell, but exciting
violent sneezing when admitted into the nostrils. Heated upon
platinum-foil, veratrine fuses into a yellow liquid, which, on cool-
ing, solidifies to a transparent yellow mass; at a stronger heat, it
is charred, and burns wholly away.
Veratrine is soluble in 3 parts of alcohol at 15° C. (59^ F.), and
more freely in boiling alcohol ; also soluble in 6 parts of ether, 2
parts of chloroform, 96 parts of glycerin, and 56 parts of olive
oil; it is almost insoluble in cold, and very sparingly soluble in
boiling, water, requiring of the latter 1560 parts for solution, but
II
VERATRINA. 585
imparts to it an acrid taste and a feebly alkaline reaction ; dilute
aoids dissolve it freely with the formation of mostly uncrystal-
lizable, gum-like salts. The solution in diluted acids has a per-
sistent acrid, though not bitter, taste, causing a sensation of tin-
gling, with numbness of the tongue. It gives a white precipitate
with tannic acid and with pot assio- mere uric iodide, a brown one
with iodinizcd solution of potnssium iodide, and a white one with
the alkaline hydrates, soluble in a large excess of the precipitant,
and more readily in alcohol, ether, and chloroform.
Concentrated sulphuric acid dissolves veratrine with a yellow
color, which successively becomes orange, purple, and deep red or
violet; gentle heat accelerates this reaction, and, if to the freshly
repared acid solution a few dro]>s of bromine-water be added, the
iquid assumes at once a purple-red color. On triturating vera-
trine with sulphuric acid in a glass mortar, the yellow or yellow-
ish-red solution exhibits, in reflected light, a fine greenish-yellow
fluorescence, which becomes more intense on adding more sul-
phuric acid. If a little cane-sugar be strewn upon the surface of
the solution of veratrine in concentrated sulphuric acid, or if the
alkaloid, previously triturated with about five times its weight of
cane-sugar, be brought into concentrated sulphuric acid, the mix-
ture assumes successively a yellowish, then a green, and finally a
beautiful blue color, afterwards slowly changing to red and gray.
Concentrated hydrochloric acid dissolves veratrine in the cold
without coloration, but, upon gently heating, the solution assumes
a permanent dark red color. Concentrated nitric acid does not
eftect any coloration with veratrine ; nor does concentrated sul-
phuric acid, when diluted with one-third its bulk of water, produce
any coloration, unless heated.
When heated with caustic alkalies, veratrine is resolved into a
new base, ven'ne, C^II^^NOg, and dimethyUprotocatechuic or veralric
r /OCII3 ^
acirf, c,H,,o, - (Cen3focn, |.
V \COOH 7
Examination :
Mineral or other insolMe admix'urps may readily be detected
by their insolubility in chloroform and in alcohol, or by leaving
a non-volatile residue when heated upon platinum-foil.
Foreifjn alkaloids may in many instances be detected by their
greater solubility in hot water, and may subsequently be recog-
nized in the solution by means of the appropriate reagents.
Brucine remains undissolved when digested with ether ;* it may
also be confirmed or recognized by dissolving a little of the ve-
ratrine in concentrated nitric acid, diluted with an equal part of
water; veratrine yields a colorless solution, which, however, will
♦ The solubility of commercial veratrine in ether varies, some kinds being
less readily soluble, and the crystalliae more so than the amorphous.
586 MANUAL OF CHSMICAL ANALYSIS.
appear red when bracine is present ; the red solution changes to
yellow upon heating, and, by the subsequent addition of a few
drops of a solution of stannous chloride or ammonium sulphide, a
violet color will be produced. None of these color reactions will
take place with pure veratrine.
For the separation of veratrine from other alkaloids, or from
complex organic mixtures with which it may be associated, see
page 108.
ZINCI ACETA8.
ZINCUM ACETICUM.
Acetate of Zinc. Zinc Acetate,
Ger. Essigsaurcs Zinkoxyd ; Fr. Acetate de zinc ; Sp. Acetato de zinc.
Zn(C,H,0,),-f3H,0; 236.9.
Colorless, translucent, six-sided tablets or scales, belonging to
the monoclinic system, of a pearly, unctuous lustre, flexible, and
with a faint odor of acetic acid, which is freely evolved when the
crystals arc treated with sulphuric acid; they contain three
molecules (22.88 per cent.) of water of crystallization, and are
ordinarily permanent in the air, but efflorescent in air that is dry
and warm. When heated upon charcoal, before the blow-pipe,
zinc acetate undergoes aqueous fusion, solidifies again, after the
evaporation of the water of crystallization, and emits vapors of
acetic acid, and the products of decomposition of the latter;
finally zinc oxide is left behind, which is yellow while hot, and
white when cold. When this residue is moistened with one drop
of solution of cobaltous nitrate, and heated to redness, it will
apj>ear green, after cooling.
Zinc acetate is soluble in 8 parts of water and in 30 parts of
alcohol at 15° C. (59^ F.); in 1.5 parts of boiling water and ia
3 parts of boiling alcohol. The a(i[ueous solution has an astrin-
gent, metallic taste, and a slightly acid reaction ; it gives a white
precipitate of zinc sulphide with hydrogen sulphide or ammo-
nium sul})liide, and a white precipitate of zinc ferrocyauidi* with
potassium ferrocyanide ; it also forms white precipitates with the
alkaline hydrates and carbonates, of which those with the hy-
drates, and with ammonium carbonate, are redissolved by an
excess of the precipitant, but these solutions are precipitated
again, by boiling, if not too concentrated.
Solution of zinc acetate acquires a red color, upon the addition
of a few drops of a dilute solution of a ferric salt.
Examination :
If a solution of one part of the salt in ten parts of water be
ziNCUM. 587
completely precipitated by hydrogen sulphide, and filtered, the
filtrate should leave no residue upon evaporation.
Metallic impurities will be indicated by a dark coloration or a
precipitate, when a solution of the salt, acidulated with hydro-
chloric acid, is saturated with hydrogen sulphide.
Iron, aluminium^ and alkaline earths will be indicated in the
solution of the salt by a brownish coloration or an insoluble pre-
cipitate upon the addition of an excess of solution of ammonium
carbonate; if to the clear filtrate a white precipitate be pro-
duced upon the subsequent addition of a few drops of solution of
sodium phosphate, mac/nesium salts will be indicated.
Alkaline salts may be recognized by a strongly alkaline reaction,
when a small portion of the salt is completely reduced upon char-
coal, before the blow-pipe, and the residue tested with moist blue
litmus-paper; or, a solution of the salt is completely precipitated
by ammonium sulphide and filtered ; the filtrate evaporated to
dryness, and subsequently ignited ; a fixed residue, having a
strongly alkaline reaction, will indicate the above-mentioned
impurity.
ZINCI BROMIDUM.
ZINCUM BROMATUM.
Bromide of Zinc, Zine Bromide,
Ger. Bromzink ; Fr. Bromure de zinc ; Sp. Bromuro de zinc.
ZnBr,; 224.5.
A white, or nearly white, granular j)owder, very deliquescent,
having a sharp saline and metallic taste, and neutral in its action
upon litmus. When strongly heated, it fuses, and, at a higher
temperature, may be sublimed in the form of white, prismatic
needles.
Zinc bromide is very freely soluble in water and in alcohol.
Its aqueous solution yields white precipitates with potassium
ferrocyanide and ammonium sulphide, and a yellowish-white one
with argentic nitrate, soluble in a large excess of ammonia-water ;
it also forms white precipitates with the alkaline hydrates and
carbonates, of which those with the hydrates, and with ammo-
nium carbonate, are redissolved by an excess of the precipitant,
but these solutions are precipitated again, by boiling, if not too
concentrated. If to the solution a few drops of carbon bisulphide
be added, and subsequently chlorine- water, drop by drop, and the
mixture agitated, the carbon bisulphide will assume a yellowish
or brownish-red color.
One gram of the dry salt, when completely precipitated by
588 MANUAL 07 CHBXICAL ANALYSIS.
argentic nitrate, yielda a precipitate of argentic bromide, which,
when washed and dried, should weigh 1.67 grams.
Ezaminatioii :
Metallic impurities will be indicated in the solution of the salt,
acidulated with hydrochloric acid, by a dark coloration or a pre-
cipitate upon saturation with hydrogen sulphide.
/ron, aluminium, and alkaline earths will be indicated in the
solution of the salt by a brownish coloration or an insoluble pre-
cipitate upon the addition of solution of ammonium carbonate in
excess; if to the clear filtrate a white precipitate be produced
upon the subsequent addition of a few drops of solution of sodium
pnosphate, maf/nesium salts will be indicated.
Alkalies and alkaline earths may be recognized by completely
precipitating a solution of the salt with ammonium sulphide,
filtering, evaporating the filtrate to dryness, and subsequently
igniting; a fixed residue, having a strongly alkaline reaction to
test-paper, will reveal the above-mentioned impurities.
ZINCI CARBONAS PRACIPITATUS.
ZINCUM CARBONICUM PR^CIPITATUM.
Precipitated Carbonate of Zine. Precipitated Zinc Carbonate.
Ger. Basisch kohlensaurcs Zinkoxyd ; Fr. Carbonate de zinc ; Sp. Carbonato
de zinc.
2(ZnC03) + 3Zn(0n), ; 546.5.
An impalpable white powder, permanent in the air, and without
odor or taste. When strongly heated in a small porcelain cru-
cible, or when heated on charcoal before the blow-pipe, it loses
water and carbonic acid gas, and leaves a residue of zinc oxide,
which is yellow while hot and white when cold.
Precipitated zinc carbonate is insoluble in both water and alco-
hol, but dissolves readily in acetic and the dilute mineral acids,
with the liberation of carbonic acid gas. When the salt, in slight
excess, is digested with dilute hydrochloric acid, and the solution
subsequently filtered, the filtrate should afford the reactions and
corres})ond to the tests of purity described under zinc chloride, on
pages 5S9, 590 ; when digested with a small amount of water, and
iiltered, the filtrate should leave no residue on evaporation, indi-
cating the absence of soluble sails.
This hoolc is the jyropt,-> ,
COOPER MEDICAL COLLING..
SAN FRANCISCO. CAL.
and is not fo he r^mor^d j]om (ht*
U "f^
1 1
ZTNCUM. 589
ZINCI CHLORIDUM.
ZINCUM CHLORATUM. ZINCUM MURIATICUM.
Chloride of Zinc, Zinc Chloride.
Ger. Chlorzink ; Fr. Chlorure de zinc ; Sp. Cloruro de zinc.
ZnCl,; 135.7.
A colorless, coherent, granular powder, or colorless, opaque rods
or fragments, very deliquescent and caustic. When heated to
about 115° C. (239° F.), zinc chloride fuses to a clear liquid, which,
on cooling, congeals to a white or grayish-white mass; at a higher
temperature it volatilizes with partial decomposition, emitting
dense white vapors, which condense on cooling in the form of
needle-shaped crystals, and leaving behind a slight residue, which
is yellow while hot and white when cold.
Zinc chloride is soluble in water, glycerin, alcohol, and ether,
giving more or less turbid, and slightly acid, solutions, which,
however, become clear upon the addition of hydrochloric acid ;
the aqueous solution yields white precipitates with potassium
ferrocyanide, ammonium sulphide, and with the alkaline hydrates
and carbonates, of which those with the alkaline hydrates and
ammonium carbonate are readily soluble in an excess of the pre-
cipitant; the latter solutions may be again precipitated either by
hydrogen sulphide or by boiling. The solution of zinc chloride,
acidulated with nitric acid, yields, when diluted with water, a
curdy white precipitate with argentic nitrate, soluble in ammcmia-
water, and it occasions white precipitates with liquids containing
albumen or gluten.
One gram of the dried salt, when completely precipitated with
argentic nitrate, yields a precipitate of argentic chloride, which,
when washed ana dried, should weigh 2.11 grams.
Examination :
Metallic impurities (arsenic, cadmium, copper, lead) may be de-
tected in the solution of the salt, acidulated with hydrochloric
acid, by a dark coloration or a precipitate upon saturation with
hydrogen sulphide. If a black precipitate is produced, it may
indicate either lead or copper ; these may be distinguished by the
addition of ammonia-water in excess to a little of the original
solution, when a blue coloration of the liquid will reveal the pres-
ence of copper. If a yellow precipitate is produced in the acidu-
lated solution by hydrogen sulphide, it will indicate either arsenic
or cadmium ; these may be distinguished or separated from each
other by digesting the precipitate with ammonium sulphide, in
which arsenious sulphide is soluble ; or, a small portion of the
zinc chloride, dissolved in concentrated hydrochloric acid, is heated
to boiling with a few drops of solution of stannous chloride or a
fragment of pure tin-foil, when an ensuing brown precipitate will
590 MANUAL OF CHEMICAL ANALYSIS.
reveal the presence of arsenic. The presence of cadmiunn will
likewise be further indicated in a solution of the salt by the addi-
tion of potassium or sodium hydrate in excess, in which the
precipitated cadmium hydrate is insoluble.
Oilchjrii and Mafjnesium Chlorides^ Alkalies and their Salts, — A
solution of the salt is completely precipitated by ammonium sul-
phide, filtered, and the filtrate tested with ammonium oxalate;
a white precipitate will reveal the presence of calcinm: the fil-
trate from the latter, if present, is subsequently tested with ammo-
nium j)hosphate, when an ensuing white crystalline precipitate
will indicate magnesium. The final filtrate from the preceding
test, when evaporated to dryness, and ignited at a gentle heat,
should leave no residue, otherwise an admixture of alkalies or
their salts will be indicated.
Ammonium chloride (ammonio-zinc chloride) may be detected
by an ammoniacal odor, and by white vapors when a glass rod,
moistened with acetic acid, is held in the orifice of the test-tube,
wherein a small portion of the salt is heated with a strong solu-
tion of potassium hydrate.
tSulfthate may be recognized in the diluted solution, acidulated
with hydrochloric acid, by an ensuing white precipitate on test-
ing with barium chloride.
ZINCI lODIDUM.
ZINCUM lODATUM.
Iodide of Zine. Zinc Iodide.
Oct. Jodzlnk ; Fr. lodure de zinc ; Sp. loduro de zinc.
Znl,; 318.1.
A white, or nearly white, granular powder, which, when ex-
posed to the air, first absorbs water and deliquesces, and after-
wards takes up oxygen with the liberation of iodine. When
strongly heated, it readily fuses to a colorless liquid, and, at a
higher temperature, sublimes in the form of quadratic prisms or
needles.
Zinc iodide is very freely soluble in both water and alcohol,
yielding solutions which j>ossess a sharp saline and metallic taste
and an acid reaction. The aqueous solution yields white precipi-
tates with potassium ferroeyanide, ammonium sulphide, and the
alkaline hydrates and carbonates, of which those with the alka-
line hydrates and ammonium carbonate are readily soluble in an
excess of the precipitant; the latter solutions may again be pre-
cipitated by hydrogen sulphide or by boiling. The aqueous solu-
tion also yields a yellow j)recipitate with solution of plumbic ace-
tate, and a red one with mercuric chloride; the latter precipitate
being soluble in an excess of the precij)itant. If to a solution of
ZINCUM. 591
the salt a little chlorine-water be added, and the mixture subse-
quently agitated with a few drops of chloroform or carbon bisul-
phide, the latter will acquire a reddish or violet color.
One gram of the dried salt, when completely precipitated by
argentic nitrate, yields a precipitate of argentic iodide, which,
when washed and dried at 100° C. (212° F!), should weigh 1.47
grams.
Examination :
Zinc or amrnonivm chlorides (ammonio-zinc chloride) may be
detected by completely precipitating a solution of the salt with
argentic nitrate, collecting the precipitate on a filter, and, after
washing with water, digesting it with ammonia- water ; the mix-
ture is then filtered, and the filtrate supersaturated with nitric
acid, when an ensuing white precipitate will reveal the presence
of chloride.
Metallic and other imjmrities may be detected by the same tests
and method of examination, as described under zinc chloride, ou
pages 589, 590.
ZINCI OXIDUM.
ZINCUM OXYDATUM. FLORES ZINCI.
Oxide of Zinc, Zinc Oxide.
Ger. Zinkoxyd, Zinkwciss; Fr. Oxyde de zinc ; Sp. Oxido de zinc.
ZnO; 80.9.
A soft, white powder, having occasionally a pale yellowish tint,
inodorous and tasteless, and not becoming discolored in contact
with hydrogen sulphide. When heated in a dry tube or a porce-
lain crucible, it neither fuses nor volatilizes, but assumes a lemon-
yellow color, which disappears again on cooling; when the oxide
18 subsequently heated with a mixture of equal parts of acetic
acid and water, it dissolves wholly and without effervescence.
When moistened with one drop of solution of cobaltous nitrate,
and heated in the flame of the blow-pipe, zinc oxide assumes a
green color.
Zinc oxide is insoluble in water, glycerin, and alcohol, but solu-
ble in diluted acids, forming colorless solutions, which, with the
exception of the solution in acetic acid, arc not affected by hydro-
gen sulphide, and the latter solution should afford with this
reagent a purely white precipitate ; the neutral solutions, with
the exception of the acetate, are only incompletely precipitated
by hydrogen sulphide, but completely by ammonium sulphide;
when alkaline, they are wholly precipitated by both reagents.
The solutions of zinc oxide form white precipitates with the alka-
line hydrates and carbonates, of which those with the former, and
592 MANUAL OP CHEMICAL ANALYSIS.
with ammonium carbonate, are soluble in an excess of the precipi-
tant, but they are re precipitated from these solutions, if not too
concentrated, by boiling. Zinc oxide is, therefore, soluble in con-
centrated solutions of the alkaline hydrates (when free from car-
bonates), and of ammonium carbonate.
Zinc oxide absorbs carbonic acid slowly from the atmosphere.
Examination :
Sulphates and Chlorides, — A small portion of the zinc oxide is
agitated for a few minutes with about ten times its weight of boil-
ing water, and subsequently filtered; a few drops of the filtrate,
evaporated upon platinum-foil, should leave no residue; nor
should the filtrate, after the addition of a few drops of nitric acid,
give any reaction with barium nitrate or with argentic nitrate.
Carbonate^ Sulphates and Phosphates of the Alkaline- JEarths, and
Alumina. — The oxide left on the filter in the preceding test is dis-
solved, with the aid of heat, in a small amount of acetic acid diluted
with an equal volume of water; effervescence would indicate car-
honates^ and an insoluble residue, calcium or barium sulphates (zinc
oxide prepared in the dry way generally leaves a small gray resi-
due, consisting of minute particles of metallic zinc, readily soluble
in hydrochloric or nitric acid); the solution is filtered, if neces-
sary, and is then supersaturated with ammonia- water ; the ensuing
white turbidity must disappear upon the addition of an excess of
the reagent; a permanent turbidity would indicate earthy phos-
jthates or alumina.
Metallic Impurities (copper, lead, arsenic, and cadmium). — A
portion of the zinc oxide is dissolved in dilute hydrochloric acid,
the solution dihited with a little water, and subsequently satu-
rated with hydrogen sulphide ; an ensuing black precipitate
would indicate cither copper or lea;/. The former will have been
indicated in the preceding test by a blue coloration of the liquid
u[)on supersaturating the acid solution of the oxide with ammo-
nia-water; it may also be detected in the dilute acid solution by
a brown coloration on the addition of a few drops of solution of
potassium fcrrocyanide. Lead may be specially tested for, if
required, by dissolving a small portion of the zinc oxide in 10
times its weight of warm diluted acetic acid, and to the clear
solution subsequently adding a few drops of solution of potassium
iodide ; an ensuing yellow coloration or precipitate would reveal
the presence of lead.
If a yellow precipitate has been produced in the acid solution
by hydrogen sulphide, it will indicate either arsenic or cadmium.
These may be distinguished as follows : The precipitate is col-
lected on a filter, washed with water, and digested wiih a concen-
trated solution (;f ammonium carbonate; arsenious sulphide is
thereby dissolved, and may be confirmed by the application of
Fleitmann's test, as described on pages 36, 37, or, if the solution
ziNCUM. 593
be not too dilute, it may be reprccipitated by subsequent super.
saturation with liydrocliloric acid. Cadmium sulphide is insolu-
ble in ammonium carbon-
Bte, and may be recognized F'o. 173.
by a red-brown coating of
the coal, when heated with
& little ex.siccated sodium
carbonate upon cliareoal be-
fore the blow-pipe (Fig.
175).
Am a confirmatory test
for arsenic, or to detect a
minute quantity of it, a
small portion of the oxide
may be dissolved in about
ten times its weight of con-
centrated hydrochloric acid, and, after the addition of a few
drops of concentrated solution of stannous chloride or a fragment
of pure tin-foil, heated to boiling; a brown turbidity would con-
firm the presence of arsenic.
Iron, Cakium, and Afa'jne.iivrn. — The acid solution, after satu-
ration with hydrogen sulphide, as described in the preceding test,
is neutralized with ammonia-water, and completely precipitated
by ammonium sulphide; a purely white precipitate should ensue;
a black coloration would indicate iron. The filtrate from the
latter precipitate is heated to boiling, filtered, and the filtrate
tested with ammonium oxalate, when a white precipitate will
reveal the presence of calcium; the filtrate from the latter pre-
cipitate is subsequently tested with ammonium phosphate, when
a white, crystalline precipitate will indicate viat/nesium.
ZmCl PBOSPHIDITH.
ZINCUM PHOSPHORATUM.
Phonphidt It/ Zinc. Zinc Pkotphide.
Ger. PLoepliorzink ; Fr. Pbospbiire <ie linc ; Sp. Fosfido de zinc.
Zn,P,; 25G.7.
A grayish powder, or minutely crvstalline, friable fragments,
having a bright, metallic, bismuth-like lustre. It possesses a
faint odor, and the taste of phosphorus, and is permanent in the
air. When strongly heated, with exclusion of air, zinc phosphide
fuses and is completely volatili»jd ; if heated with access of air it
is principally converted into zinc phosphate.
Zinc phosphide is insoluble in water or alcohol, but is readily
594 HAXCAL OF CHEMICAL AKALTSIS.
and completely soluble in dilute bydrochloric and siilpharic
aci(U. witli the evuiution of sjMjntaneou.eJr iutl.imma1il« hydrogen
jib'^jjliide. When difisolve'l in dilute bydrochluric acid, with the
enrjpJovnient uf a siigbt excess of the salt, filtered, and &ub^-
quently heated to ex[je] the hydruyen phosphide, a solution is
obtained wbicli yields white precipitates with poiassium ferro-
cyanide. nrnmotiium sulphide, and with the alkaline hydrates
and carbonates; of these, the precipitates produced by the alka-
line hydrates and amnionium carbonate are readily eoloble in an
excess of the precipitant.
Examfnatioa :
Zi-iiC jihosphiite, traces of which are usuallv contained in the
phosphide, may be extracted by digestion with a cold .«olution of
ammonium chloride, and may subsequently be recognized by an
ensuing white crystalline precipitate on the addition of ammonia-
water and solution of magnesium sulphate.
MelalUr nud other impurities may be detected in the solution of
zinc phosphide in diluted hydrochloric acid by the same tests
and methixls of examination an described under Zinc Chloride, on
pages 5y!l, 590.
zmci snXiFHAS-
ZIN'CCM SCLFURICUM.
Sutpfiiite of Zinc. While Viln'ot. Zine Salphtile.
Off. ScliwcfelsHures Zinkoird. Weisaer Vitriol ; Fr. Sulfate de rinc;
Sp. Slllfato de ziiic.
ZnS0^+7H,0; 2»6.9.
Colorless, trnnspart-nt rhombic prisms (Figs, 176 and 177) or
iL'it'ular needles, containing 7 molecules {43.>'U per cent.) of water
0
of crystallization, and efflorescing slowly on exposure to the air.
When heated at 100° C. {2X2" F.) they lose 6 molecules (37.6 per
cent.) of water, the remaining molecule of water being eliminated
zrNCUM. 595
only at a temperature of from 230 to 240° C. (446 to 464° F.);
at a stronger heat, the salt is decomposed, sulphur dioxide and
oxygen being evolved, while a basic salt remains behind ; at a
white heat, it is completely decomposed, leaving a residue of zinc
oxide, which, when moistened with one drop of solution of co-
baltous nitrate, and heated again to redness, assumes a green color
(magnesium sulphate, when similarly treated, gives a reddish
coloration, alum a blue one).
Zinc sulphate is readilv soluble in water, 100 parts of which
dissolve at 10° C. (50° F.)^138 parts, at 20^ C. (68° F.) 161.5 parts,
and at 100° C. (212° F.) 653.5 parts, of the crystallized salt; it
is soluble in about 3 parts of glycerin, and in an excess of the
solutions of the alkaline hydrates, but it is little soluble in strong,
and not at all in absolute, alcohol ; the aqueous solution reddens
blue litmus- paper and has a metallic styptic taste, remains color-
less with solution of tannic acid, and gives a copious white pre-
cipitate with highly diluted solution of barium chloride. Its
deportment with reagents is the same as described under Zinc
Oxide, on pages 591, 592.
Examination :
Mttallic Impurities, — A C(mcentrated solution of zinc sulphate
is slightly acidulated with a few drops of diluted hydrochloric
acid, and subsequently saturated with hydrogen sulphide ; no tur-
bidity or coloration should ensue ; a dark or yellowish coloration or
precipitate would indicate copper^ lead^ cadmium^ or arsenic. The
filtered liquid, upon subsequent supersaturation with ammonia-
water, should yield a perfectly white precipitate ; a dark coloration
would indicate the presence of iron.
The same test may serve to distinguish at once magnesium sul-
phate from zinc sulphate ; these substances, being isomorphous
and of a similar appearance, arc liable to be taken one for the
other: solution of magnesium sulphate is not acted upon by
hydrogen sulphide, ammonium sulphide, or potassium ferrocv-
anidc, and the precipitate produced by solutions of potassium or
sodium hydrate are insoluble in an excess of the precipitant.
Magnesium and aluminium sulphates are further indicated by
the following tests: To a solution of the zinc sulphate a little
ammonium chloride is added, and subsequently ammonia- water
in considerable excess ; the precipitate tlrst formed should become
completely dissolved; an insoluble flocculent precipitate would
indicate aluminium. The filtered liquid is subsequently tested
with ammonium phosphate, when the immediate or gradual forma-
tion of a white, crystalline precipitate will indicate magnesium.
Potassium and sodium sulphates may be detected by adding to
a solution of the zinc sulphate a solution of plumbic acetate until
a precipitate ceases to be produced, filtering, and subsequently
completely precipitating the zinc and excess of lead by hydrogen
sulphide; the filtered liquid upon evaporation to dryness should
696 MANUAL OF CHEMICAL ANALYSIS.
leave no residue ; a noii- volatile residue, imparting a brown color
to moistened turmeric paper, would indicate the above-mentioned
impurities.
Ammoninm salts may be recognized by the odor of ammonia,
and by the development of white fumes, when a glass rod, moist-
ened with acetic acid, is held over the orifice of the test tube in
which a little zinc sulphate has been heated with a strong solu-
tion of potassium hydrate.
('hlorkUs may be detected in a dilute solution of the salt, acidu-
lated with nitric acid, by a white precipitate on the addition of
solution of argentic nitrate.
Nitrates may be detected by ensuing decoloration of the liquid,
when a solution of the salt, tinted with a drop of indigo solution.
Fig. 178.
is gently heated with a few drops of concentrated sulphuric acid;
or, a crystal uf ferrous sulphate is dissolved in a solution of the
salt, and the liquid carefully poured upon a little concentrated
sulphuric acid, in a test-tube, so as to form two layers (Fig. 178);
a violet or brown coloration at the line of contact of the two
liquids will reveal the presence of nitrates.
^i^ 'bool is the jyroiH ,
COOPEit MEDICAL COLL:- ...
SAN rRANCJSCO. OAL
ziNcuM. 597
ZINCI SULPHOCARBOLAS.
ZINCUM 8ULF0CARB0LICUM. ZINCUM SULFOPHENYLICUM.
S^lphocarbolats or Sulphophenylaie of Zinc. Zinc Sulphocarbolate,
Ger. PhenoUulfosaures Zinkoxyd ; Fr. Sulfocarbolate de zinc ;
Sp. Sulfocarbolato de zinc.
Zn(C,H,.0H.S03), + 8H,0 ; 554.9.
Colorless, transparent, rhombic prisms or plates, or a white,
crystalline powder, odorless, or possessing but a slight odor of
phenol, and readily efflorescing on exposure to dry air. The salt
contains 8 molecules (26 per cent.) of water of crystallization,
which are expelled at a temperature of 130^ C. (266° F.); when
more strongly heated, the salt is decomposed, with the liberation
of sulphur dioxide and phenol, and leaving a residue of carbon
and zinc sulphate, which, at a strong red heat, is completely con-
verted into zinc oxide.
Zinc sulphocarbolate is soluble in 2 parts of water and 5 parts
of alcohol at 15° C. (59^ F.), yielding slightly acid solutions,
which, when diluted, aflbrd a deep violet color on the addition of
a few drops of solution of ferric chloride, and a white precipitate
upon saturation with hydrogen sulphide ; it also yields white
precipitates with* potassium ferrocyanide, ammonium sulphide,
and with the alkaline hvdrates and carbonates, of which those
with the alkaline hvdrates and ammonium carbonate are readily
soluble in an excess of the precipitant.
One hundred parts of the salt, when strongly ignited at a red
heat, leave a residue of zinc oxide, weighing 14..58 parts.
Examination :
Zinc sulphate may be detected by the incomplete solubility of
the salt in alcohol, or by the occurrence of a turbidity or precipi-
tate when a concentrated aqueous solution of the salt is dropped
into alcohol, as also by the formation of a white precipitate wlien
the dilute aqueous solution of the salt is tested with barium
chloride.
Metallic impurities may be detected by a dark coloration or a
precipitate when the aqueous solution of the salt, acidulated with
nydrochloric acid, is saturated with hydrogen sulphide.
Salts of the Alkalies and Alkaline- Earths, — A portion of the salt
is dissolved in ten times its weight of water, and to the solution
ammonia- water in slight excess is added, until the precipitate at
first produced is redissolved ; an incomj)lete solution would indi-
cate the presence of a Z?^?7?m?'?^m and mafjnesium. The clear liquid
is subsequently saturated with hydrogen sulphide until the zinc
has become completely precipitated, filtered, and the filtrate tested
with ammonium carbonate: a* white precipitate would indicate
barium or calcium; the filtrate from the latter precipitate, should
598 MANUAL OF CHEMICAL ANALYSIS.
such have been produced, is evaporated to dryness, and subse-
quently ignited in a small porcelain crucible, when a non-volatile
residue will indicate salts of the alkalies.
ZINCI VALERIAN AS.
ZINCUM VALERIANICUM.
Valerianate of Zinc, Zinc Valerianate,
Ger. BaldriansauresZinkoxyd ; Fr. Valerianate dezmc; Sp. Valerianato de zinc.
Zn(C.H,0,), -f H,0 ; 284.9.
White, pearly, lamellar crystals, or a white, scaly, crystalline
powder, permanent in the air, somewhat unctuous to the touch,
and with a feeble odor of valerianic acid. It contains 1 molecule
(6.3 per cent.) of water of crystallization, which is eliminated at a
temperature of 100° C. (212° F.), and is not again absorbed by
subsequent exposure to the air; at a higher temperature (about
146° C. =» 284° F.) the salt fuses, with partial decomposition, to
a clear, thick liquid, and solidifies again upon cooling in a crystal-
line form ; when strongly heated, it evolves white, inflammable
vapors, leaving a residue of zinc oxide, which, when moistened
with a <lrop of a solution of cobaltous nitrate, and reheated to
redness, becomes green.
Zinc valerianate is soluble in 100 parts of water and in 40 parts
of alcohol at lo*^ C. (59° F.), and is also soluble in glycerin, and
in an excess of ammonia-water, bat only sparingly in ether or
chloroform. Its solutions redden blue litmus-paper, and become
turbid upon gently warming, but clear again on cooling; by pro-
longed boilinti, an insoluble basic salt is deposited, having the
eomi)osition Zn(C,HgOj)2-f 2Zn(0n)j. The salt is also readily
soluble in diluted acids, but with decomposition, and consequent
turbidity from the elimination of the valerianic acid, which grad-
ually collects as an oily stratum upon the surface of the aqueous
solution; an addition of ammonia- water at first increases the tur-
bidity, but, when added in excess, forms a clear solution, which
yields a white precii)itate with ammonium sulphide.
The (lei)ortinent of solutions of zinc valerianate with reagents,
after the elimination of the acid by hydrochloric or sulphuric
acid, is the same as described under Zinc Oxide, on pages 591, 592.
One gram of the salt, when moistened with nitric acid, evapo-
rated to dryness, and ignited at a red heat, should leave a residue
of zinc oxide weighing 0.283 gram : or, when the anhydrous salt
has been em|)loyed, the residue should weigh 0.303 gram.
Examination \
Zinc (icHatc may be detected by agitating a little of the tritu-
rated zinc valerianate, in a test-tube, with about four times its
weight of cold water, and adding to the filtrate one or two drops
of ferric chloride; the liquid, if necesaary, is filtered again, aod
must appear almost colorless; a reddish tint would indicate acetic
auid.
Tartaric and Oxalic Acids. — The undinsolved valerianate of the
preceding test is rinsed tliniugh the broken fiUcr into a test-tube,
and is agitated with a sufficient quantity of am monia- water ; a
ootnplete solution must take place, which should retain its trans-
parency on tlie addition of a few drops of solution of calcium
chloritfc; a white turbidity or precipitate would indicate the
above-mentioned acids or their res|)ective salts.
Zitic hnlyrate may be detected by the occurrence of a turbidity
or precipitate when a cold, concentrated solution of the salt is
mixed with a concentrated solution of cnpric acetate; or, about
5 grams of the salt arc triturated, and added, in a small flask, to
a mixture consisting of 10 grams of concentrated sulphuric acid
and 10 grams of water ; the mixture is submitted to distillation at
a gentle heat {Fig. 1711), iinti! about 2 grams of distillate are ob-
tained ; this is agitated with a little concentrated solution of cuprio
acetate, which should not immediately affect the transparency of
the liquid, but it forms, after a while, oily drops of anhydrous
cupric valerianate, which, after from 5 to 20 minutes, pass into a
greenish-blue crystalline deposit of hydrated cupric valerianate.
If, however, the salt consists mainly or wholly of butyratc, the
transparency of the liquid would at once be impaired by the
formation of a crystalline precijutato.
The presence of butyratc, if the amount be not too small, will
likewise be indicated by dissolving the salt in the smallest pos-
sible amount of warm, absolute alcohol, saturating with hydrogen
sulphide, and, after filtration, allowing the filtrate to evaporate
Spontaneously; if the residual acid consists of ordinary butyric
600 MANUAL OF CHEMICAL ANALYSIS.
•
acid, it will be miscible in all proportions with water, whereas
valerianic acid requires 25 parts of water for solution.
Boric acid may be detected by triturating a little of the salt
with a few drops of alcohol, and by igniting and burning the mix-
ture, with stirring; a green coloration of the flame, especially
toward the termination of the ignition, would indicate boric acid.
Sulphates and chlorides may be detected in the aqueous solution
of the salt by acidulating with nitric acid, heating, in order to
expel the liberated valerianic acid, and subsequently testing the
liltered liquid, in separate portions, with barium chloride for sul-
phates, and with argentic nitrate for chlorides ; a white precipitate
in either instance would reveal the presence of such impurities.
Salts of the Alkalies and Alkaline Earths, — A portion of the salt
• is agitated with a sufficient quantity of ammonia- water to form a
complete solution; an insoluble residue would indicate aluminium
or maynesium. The ammoniacal liquid is subsequently com-
pletely precipitated by hydrogen sulphide or ammonium sulphide,
filtered, and the filtrate tested with ammonium carbonate; an
ensuing white precipitate would indicate barium or calcium; the
filtrate from the latter precipitate, if such has been produced, is
evaporated to dryness, and subsequently ignited in a small porce-
lain crucible, when a non- volatile residue will indicate salts of the
alkalies.
This hooh is fkepropenj ^
COOPER MEDICAL COLLXG...
SAN FRANCISCO. GAL.
avfl if^ not to he r^nnor^d from tht>
'•',«•
TABLES AND INDEX.
TABLES.
TABLE OF ELEMENTARY BODIES. WITEl THEIR SYMBOLS
AND ATOMIC WEIGHTS.
Sym-
1
Atomic
i
1
, Sym-
Atomic
Name.
bol.
Weight.
^ Name. bd.
1
1 Weight.
1
Aluminium . . . .
. Al
27
Molybdenum . . Mo
9o.;3
Antimony . . . .
. Sb
120
■ Nickel . .
. Ni
r)8
Arsenic ....
. As
74.9
Niobium .
Nb
94
Barium
. Ba
13G.8
Nitro;;en.
N
14
Beryllium (Glucinum^
)| Be
9
1 Osmium .
'. Os
198.5
Bismuth ....
. Hi
210
Oxvjren . .
. 0
IG
Boron ....
. B
11
1 " *•'
Palladium
. ' Pd
105.7
Brominti ....
. Br
79.8
' Phos[)horus
. 1 P
31
Cadmium . . .
. Cd
111.8
Platinum
. , Pt
194.4
Caesium . . . . .
. i Cs
132.G
Potassium
. ;k
39
Calcium ....
. ! Ca
40
1 Khodium
. ' Rh
104.1
Carbon
.'C
12
Rubidium
1
. 1 Rb
85.3
Cerium . . . . .
. ' Ce
141
Ruthenium
Ru
104.2
Chlorine
CI
3.3.4
iScandium
Sc
44
Chromium- . . . .
. Cr
r>2.4
Selenium
. 1 Se
78.8
Cobalt
. 1 Co
ri8.9
Silicon . .
Si
28
Copper
. Cu
63.2
Silver. .
. Ag
107.7
Didvmium . . . .
. Di
144.G|
j Sodium . .
. i Na
23
Erbium . . . . ,
ig:>.9,
Strontium
Sr
87.4
Fluorine
, Fl
19
Sulphur . .
S
32
Gallium
. G
G8.8
Tantalum
p
182
Gold
Au
19G.2
Tellurium
l^e
128
Hydrogen . . . .
II
1
Thallium .
Tl
203.7
Indium
ilu
113.4 .
Thorium . .
Th
233
Iodine
i I
12G.G;
' Tin . . .
, I Sn
117.7
Iridium
. 1 Ir
192.7
' Titanium
. Ti
48
Iron
Fe
5.'>.9 '
Tungsten
W
183.G
Lanthanum . . . .
La
138..>
Uranium . .
. ! U
238.5
Lead
Pb
20G.r>
; Vanadium
V
51.3
Lithium
1 Li
7
1 Ytterbium
i Yb
172.7
Magnesium . . . .
1 M-
24
1 Yttrium . .
■ !>'
89.8
Manganese . . . .
Mu
r>4
1 Zinc . . .
, Zn
64.9
Mercury
Ilg
199.7
i
1 Zirconium .
1
' Zr
1
90
TABLE OP THERMOMETRIC EQUIVALENTS
Acconliog to Ihc Centigrade aD<l Fahrenheit Scales.
... ..u.
c«..
jr.hf.
' c«..
F.h.
Cut.
F.hr.
40 — 4it,0
+ 19
+.8.«
+T
+lfi?.6
+ 138
+=.s..
W :i«.3
17
n2.fi
73
103.4
139
304.3
■J8 aa.i
18
04.4
74.
16.1.2
ISO
206.0
i(7 34,6
19
60.3
7.'>
107.0
131
267.8
3(1 :K.8
20
0>i.0
70
108. 8
133
309.6
J5 :ii.O
21
011.8
77
170.6
133
271.4
34 211.2
28
71 G
78
173.4
134
273.2
33 27.4
23
73.4
79
m.2
135
27.1.0
33 a».o
34
7'>.3
80
170.0
136
276.8
31 aa.8
2.-,
77.0
81
177.8
137
278. S
10 K.O
20
78.8
82
179.6
133
280.4
2» L'0.3
37
80.0
83
181.4
139
283.8
28 1H.4
33
83.4
84
183.2
140
284.0
ST 16.6
39
84.2
8.1
IW.O
141
285.8
36 14.8
30
86.0
86
1M.8
143
387.«
S5 I».0
31
87.8
p7
las.fl
143
289.4
34 11.3
33
89.6
88
190.4
144
391.3
S:l 0.4
3»
91.4
811
193.2
I4o
293.0
33 7.U
34
93.3
00
194.0
146
294.8
31 5. a
35
05.0
91
19-1.8
147
2»».6
30 4.0
30
m.H
93
197.6
148
298.4
11 3.3
37
9S.6
93
199.4
149
300.3
IS 0.4
33
100.4
94
301 3
150
302.0
T + 1.4
102.3
9.1
203.0
151
303.8
0 3.3
40
104.0
96
204.8
1.53
305,8
i:. .-..0
10.V8
97
300. G
153
807.4
U OS
42
107.0
98
SO-*. 4
1.54
309.3
;i S.ti
ii
10!t.4
119
310.3
155
311.0
l- 11'- 4
44
111.2
100
313.0
l.->6
313.8
11 13.3
4.-.
li:!-0
101
313.8
I.-.7
314 6
10 U.O
4S
114.8
3l.i.O
1.18
316.4
0 1.-..8
47
110.6
io5
217.4
1.19
318.2
S 1T,G
1W.4
104
219.3
100
330.0
49
130. -•
HI.-.
331.0
101
331.8
li J 1.3
Tyl
I.MJ
103
323.6
3:W.2
33S.0
339.8
341.6
343.4
341.3
347.0
348.8
3.10.6
313.4
3.14.2
TABLES.
605
T.
\BLE OF
Fahr.
THERMOMETRIC
1
1 Cent. Fahr.
r- O !
EQUIVALENTS
Cent. Fahr.
O O
Cent.
inufd.
Cent.
Fnhr.
O
O
O
o
+184
+363.2
. +221
+429.8
+258
+496.4
+295
+563.0
185
365.0
1 223
1 1
431.6
259
498.2
296
564.8
18G
306.8
' 223
433.4
260
500.0
297
566.0
187
368.6
224
435.2
261
501.8
298
568.4
188
370.4
225
437.0
263
503.6
299
570.2
189
372.3
! 226
438.8
263
505.4
300
572.0
190
374.0
. 227
440.6
264
507.2
301
573.8
191
375.8
238
442.4
205
509.0
302
575.6
192
377.6
' 229
444.3
266
510.8
303
577.4
193
379.4
230
446.0
267
512.6
304
579.2
194
381.3
■ 231
447.8
2ViS
514.4 !
305
581.0
195
;^83.0
232
449.6
269
516.2 !
306
582.8
196
384.8
233
451.4
270
518.0
307
584.6
197
386.6
1 234
453.2
271
519.8
308
586.4
198
388.4
1 235
455.0
273
621.6
309
588.2
199
390.3
236
456.8
27:^
523.4
310
590.0
200
392.0
, 237
458.6
274
525.2
311
591.8
201
393.8
288
460.4
275
527.0
312
593.6
203
395.6
1 239
462.2
276
528.8
313
595.4
203
397.4
. 240
464.0
277
530.6
314
597.2
204
399.2
241
405.8
278
632.4
315
599.0
205
401.0
243
467.6
279
534.3
316
600.8
206
403.8
! 24:j
469.4
2b0
536.0
317
602.6
207
404.6
1 244
471.2
281
537.8
318
604.4
208
406.4
' 245
473.0
2h2
539 . 6
319
606.2
209
408.3
246
474.8
2K3
541.4
320
608.0
210
410.0
247
476.6
2H4
543.3
330
626.0
211
411.8
248
47H.4
285
545.0
340
644.0
213
413.6
249
480.2
286
546 . 8
350
662.0
213
415.4
250
482.0
2H7
548.6
360
680.0
214
417.2
251
483.8
288
550.4
370
698.0
215
419.0
253
485.6
289
552.2
380
716.0
216
420.8
253
487.4
21)0
554.0
390
734.0
217
423.6
254
489.2
291
555 . 8
400
752.0
218
424.4
1 255
491 0
292
557.6
410
770.0
219
426.3
. 256
492.8
293
559.4
420
788.0
220
428.0
. 257
I
494.6
294
561.2
430
806.0
Formula for converting df green of the Centigrade »en1e into tho»e of
Fahrenheit (D representing the degree to be converted).
If above the freezine point of water, 32^ F. (0^ C.)
D
X 9 + 82.
If below freezinpj, but above ^-' F. ( — 17.77^ C.) 32 (P X oY
If below Oo F. (—17.770 C.) — /^ o^— 32-
\ 5 X 9/
Formula for converting degreen of the Fahrenheit ncale into tho*e of Centigrade.
If above the freezing point of water, 32^ F. (OO C.) '-^—32) ^ ^
If below freezing, but above 0^ F. (—17.77 C.) — !?^~1^^ v 5
If below 00 F. (— 17.770 C.)
_^l>+32)^-
9 -^^'
606
TABLES.
TABLE FOR CONVERTING METRIC MEASURES OF CAPACITY
INTO UNITED STATES FLUID MEASURES.
Cubic
centu
Minimd.
Cubic
reiiii-
1 1
Fluid Fluid Minims.
Cubic
centi-
Fluid
Fluid
Minims
meters.
meters.
0.65
ounces, dr'
bms.
meters.
ounces.
dr*bms.
0.01
0.16
. .
10.55
46
4
26.40
0.02
0.32
0.70
11.36
47
4
42.60
0.03
0.49
0,75
12.17
48
4
58.80
0.04
0.65
0.80
12.98
49
5
16.00
0.05
0.81
0.85
13.80
1 50
^
5
81.80
O.OC
0.97
0.90
.. , 14.61
60
2
• •
14.40
0.07
1.14
0.95
.. 1 15.42
70
2
2
56.40
0.08
1.30
: 1
16.23
80
2
5
86.60
0.09
1.46
' 2
32.46
00
8
21.00
0.10
1.62
. 3 i .
48.69
! 100
8
8
3 60
0.11
1.79
4
1 4.80
110
8
5
46.20
0.12
1.95
5
• 1
1 , 21.00
120
4
• .
28.20
0.18
2.11
6
1
1 37.20 '
i 180
4
3
8.40
0.14
2.27
7
. 1
1 53.40 i
140
4
5
52.80
0.15
2.43
8
i
2 9.60 ;
150
5
• •
35.40
0.16
2.60
9
2 25.80
160
5
3
18.00
0.17
2.76
10
1
2 42.60
170
5
6
0.18
2.92
11
'
2 58.88
180
6
• •
40.20
0.19
8.08
12
:
8 15.06
: 190
6
8
24.60
0.20
8.25
13
8 81.29 :
200
6
6
7.20
0.21
8.41
14
. 1
8 ; 57.40
225
7
4
52.85
0.22
8.57
15
1
4 13.60
250
8
8
30.00
0.23
3.74
16
4 19.80
275
9
2
24.65
0.24
3.90
17
4 86.00
800
10
1
10.80
0.25
4.06
18
4 52.20
325
10
7
56.40
0.26
4.22
19
1
5 8.40
850
11
6
42.60
0.27
4.39
1 20
^
5 24.60
375
12
5
28.20
0.28
4 . 55
' 21
5 40.83
400
13
4
14.40
0.29
4.71
, 22
5 57.06
425
14
8
0.30
4.87
i 23
6 13.29
450
15
1
46.20
0.31
5.03
' 24
6 29.40
i 475
16
• •
31.80
0.32
5.19
25
6 45.60 1
500
16
7
18.00
0.33
5.30
20
7 1.80 '
525
17
6
3.60
0.34
5 . 52
27 , .
7 18.00
550
18
4
49.80
0.35
5 . 08
28 ' .
7 1 34.20
575
19
8
35.40
0.30
5.84
29
7 50.40
600
20
2
■ 21.60
0.37
6.01
30
i
1
4.80
; 625
21
1
17.20
0.38
6.17
31
1
1
21.03
; 650
21
7
53.40
0.39
6 . 33
32 1
37.26
675
22
6
49.00
0.40
6.49
33 1
4
53.49
, 700
23
5
25.20
0.41
6 . 65
34 I
1 9.00
725
24
4
10.80
0.42
0.81
35 1
1 25 . 80
750
25
2
57.00
0.43
6.98
30 I
1 42.00
775
26
1
42.60
0.44
7.14
37 1
1 58.20
800
27
0
28.80
0.45
7.30
38 1
2 14.40
825
27
7
14.40
0.46
7.46
39 1
2 30.00
850
28
6
0.60
0.47
7.63
40 1
2 49.20 ;
; 875
29
4
46.20
0.48
7.79
41 1
3 j 5.43
900
30
8
32.40
0.49
7.95 ,
42 1
3 21.06
925
81
2
18.00
0.50
8.12
43 1
3 1 87.89
950
82
1
4.20
0.55
8.93
44 : 1
8 1 54.00
975
82
7
49.80
0.60
9.74
' 45
1
4 10.20 1
1000
83
6
86.00
TABLES.
607
TABLE FOR CONVERTING UNITED STATES FLUID MEASURES
INTO METRIC MEASURES OF CAPACITY.
Cubic
Fluid Cubic
Fluid
Cubic
nims.
centimeters. ainimH. diKchmii. ceDtimetern.
OaDCOK.
centimeten
1
0.06 i
18 .. 2.64
3
88.07
2
0.12 ' 4
U .. 2.71
! 4
: 118.24
8
0.18 <
15 .. 2.77 ,
5
, 147.81
4
0.25 ^
16 .. ' 2.88 '
0
177.39
5
0.81 ' ^
17 .. 2.89
7
200.90
6
0.87 i ^
18 .1 2.95
! 8
230.53
7
0.43 !
19 1 .. ! 3.01
1 9
206.10
8
0.49
•)0 .. ! 3.08 ,
10
, 295.68
9
0.55 ,
'>5 .. 3.39 ,
11
825.25
10
0.62 (
W .. 3.70 '
12
, 354.82
11
0.68 i
)5 .. 4.01 i
13
384.40
12
0.74
rO .. 4.31 :
14
418.97
13
0.80
?5 .. 4.62
15
' 448.54
14
0.80 i
JO .. 4.93
10
473.11
15
0.92
^5 .. 5.24
17
502.69
10
0.99 1
)0 .. 5.54
18
582.26
17
1.05 J
)5 .. 5.85
19
561.93
18
1.11 1<
X) .. 6.16
20
, 591.50
19
1.17 1
10 .. 0.78
21
; 621.08
20
1.23 It
30 .. 7.39 .
22
650.65
21
' 1.29
3 11.09 !
23
! 680.22
22
, 1.30
4 14.79 ,
24
; 709.80
28
1.42 ,
5 18.48
, 25
; 789.87
24
' 1.48
0 22.18
20
1 768.94
25
1.54
7 25.88 ;
27
1 798.51
26
1.00
8 29.57 1
28
828.09
27
1.00 '
9 33.27 ,
29
857.66
28
1.7:^
10 80.97 ;
80
, 887.23
29
1.79
11 ' 40.00
81
916.80
80
1.85
12 44.80 :
82
' 946.88
81
1.91 ;
13 48.00
40
: 1188.00
82
1.97
1 14 51.75
45
1880.81
83
2.03 ■
15 55.45 i
4«
1419.58
84
2.10 '
10 59.10 '
50
1478.74
85
2.10 i
17 02.85 1
55
, 1626.55
86
2.22 1
18 00.54 i
00
, 1774.46
87
2.28
19 70.24 ,
04
1 1892.75
88
2.34
i 20 73.94
80
2866.00
89
2.40
21 77.03
90
2839.11
40
2.46
; 22 81.33
112
! 8312.22
41
2.52
23 85.08
128
1 3785.51
42
2.58
1 250
1 7571.02
608
TABLES.
TABLE FOR CONVERTING METRIC WEIGHTS INTO TROY
WEIGHTS.
Grains.
Exnct
• e(|uiva-
leiiti* ill
grainti.
i
Approximate eqiitva
in Troy weighiH
lenta
«
a
6
i ! -
s ®
1
a
S
C5
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
0.2
0.3
0.4
0.5
0.0
0.7
0.8
0.9
1.0
2.0
8.0
4.0
5.0
CO
7.0
8.0
9.0
10.0
11.0
0.1543
0.3080
0.4630
0.6173
0.7717
0.9260
I
1.0803'
1.2347
1.3890
1 . 543
3.086
4.630
6.173
7.716
9 . 259
10.803
12.340
13.889
15.432
30 . 865
40.297
61.729
77.162
92 . 594
108.026
123.459
138.891
154.323
169.756
1
1
1
1
2
2
2
o
1
2
1
2
1
2
i
\
6
TJ
tV
I
0
17
1
li
3
4J
Oi
7J
9}
10 J
14
15i
10!
CI
M
in
135
8
31
14i
\ I
Exact
equiva-
Orams. lenttf in \
grains, j
12.0 ! 185.188
13.0 200.621
14.0 216.058
15.0 231.485
16.0 246.918
17.0 I 262.350
18.0 277.782*
19.0 ; 293.215
20.0 308.647
21.0 324.079
22.0 ; 339.512
23.0 354.944
24.0 370.376;
25.0 885.809
26.0 ; 401.241
27.0 ' 416.673
28.0 , 432.106
29.0 I 447.538
30.0 462.970
31.0 478.403
32.0 I 493.835
40.0 617.294
45.0 694.456
50.0 , 771.617
60.0 925.941
70.0 1080.264
80.0 1234.588
90.0 |1388.911
100.0 1543.235
Approximate equivalents
in Tnijr weights.
m.
a
0
C
1
1
1
1
1
2
2
2
3
2 ! 3
8
8
8
4
4
4
4
5
5
5
5
6
6
6
6
7
I
I
3
4
7
2
4
7
1
1
1
2
» •
1
1
2
» •
1
1
2
> •
1
2
2
» •
1
2
2
1
o
a
s
5i
3.
16
\\\
8r'<r
3}
17}
13J
8f
191
15
lOf
5|
11
16;
12 A
7i
3
181
18J
17 A
10}
*
6
1
4
9
31
ITiis hook is iheproiKt j
COOPER MEDICAL COLLI^G^t
SAN FRANCJSCO. CAL.
€tnd is not to he rfmf»»^'il fhtni the
TABLES.
609
TABLE FOR COXVERTIXG TROY WEIGHTS INTO METRIC
WEIGHTS.
(iruliiH. (iram*«.
Gr.iiiiH.
(IruiDH.
(iraiii*«.
Gram**.
OralQH.
(tramH.
I
0.0018
30
1.94 4
59
3.833 \
88
5.703
3
0.1296
31
2.009
60
3.888
1
89
1
' 5 . 766
3
0.1944
1
33
3.073 '
61
3.953
90
; 5.831
4
0.2593
33
2.138 '
63
4.017
91
5.896
5
0.3340 [
34
3.303 '
63
4.0S3
93
5.961
0
0.3SS8
35
3.36S ;
64
4.147
93
6.036
7
0.4536
36
3.333 '
65
4.311
94
6.090
8
' 0.5184
37
3.397 1
60
4.376
95
6.155
0
0..-)S32 '
3S
3.463 1
67
4.341
96
6.330
10
0.6480
:<9
3.537
68
4.406
97
6.385
11
0.7130
40
3.593 ■
69
4.471
98
6.350
12
0.77T6
41
3.656 'i
70
4.531 1
99
6.414
13
O.H434 "
13
3.731 1
1
71
4.600
100
6.479
14
0.9073 '
43
3.786 ;'
73
4.665
130
7.776
15
0,973
44
3.851
73
4 . 730
150
9.719
16
1.037 ,
45
3.916
74
4.795
180
11.664
17
1.103 ,.
46
3.9S0 ■
75
4.859 '
, 200
13.958
IS
1.166 i'
47
3.045
1
7r»
4.934
340
15.552
19
1.331
4S
3.110
77
4.9S9
300
19.440
20
1.396
49
3.175
78
5.054
360
33.338
21
1.361 ,
50
3.334
79
5.118 !
400
35.930
22
1 1.436 ,
1 '
51
3.304 '
SO
5.183
480
31.103
23
1.490
53
3.369
81
5.348
500
33.396
24
': 1 . 555
53
3.434
83
5.313
600
38.875
25
1.630 i
54
3.499
1
83
5.378
1
700
45.354
36
' 1.6S5 ,
3.564 ;
84
5.443
800
51.833
27
i 1.749 1
56
3 63S
H5
5 . 507
900
58.313
28
■ I.S14 1
1
57
3.693 .
86
5.573
960
63.307
29
1.869 .
58
3 . 758 i
87
5 . 637
1000
64.793
39
This hook is the p'oy' ■ .
COOPER MEDICAL COLL..:..
SAN FnANOISCO. OAL.
/■ • I ■ f ■ . • ' '
}i •
(The Latin naiiios aro in Itaties.)
ACETATE of ammonium, solution
897
copper, 320
ethyl. 204
iron, solution of, 399
lead. 452
morphine, 432
potassium, 4G0
sodium, 530
zinc, 5St)
Acetic acid, 122
ether, 204
Aeetum. 117
plumbicum^ 407
Acid, acetic, 122
arsenious, 120
benzoic, 135
benzol-carhonic, 135
boracic, 137
boric, 137
carbolic, 139
chromic, 142
chrysophanic, 312
citric, 144
gallic, 147
hippuric, 136
hydriodic, 148
hydrobromic, 150
hydrochloric, 153
hydrocyanic, 159
hydrosulphuric (as reagent), 37
hypophosphorous. 103
isopropyl-acetic, 197
lactic, 164
metaphosphoric, 174
muriatic. 153
nitric, 165
oleic, 171
ortho-boric, 137
ortho-oxybenz»»ic, 181
ortho-phosphoric, 174
ozalic. 172
phenic. 139
phenyl-formic, 135
phosphoric, 174
of, Acid —
picric (as reagent), 29
I salicylic, 181
I succinic, 182
sulphuric, 184
sulphurous. 190
tannic. 192
tartaric, 195
valerianic, 197
Acids, examination for. 61
volumetric estimation of, S6
Aeitlum nreticnm, 122
amenkoium^ 126
arnenioKum^ 126
htmoieum^ 135
bnrieitm, 1 37
carhoticHTH^ 139
chromicum^ 142
cilricum^ 144
ffoliiCUM, 147
hifdriodicHM^ 148
hf/(irohromicum^ 150
ht/droch/oricum^ 153
hi/drorifitnienm^ 1 59
hf/pophoxphorosuut, 163
Itirticnm^ 164
tfiHriatJrnm, 153
nitrieum^ 165
olrirftiH, 171
oUinicNm, 171
ozalicum^ 172
phenyhcum, 139
phoKphoricum^ 174
salirtflitmny 181
succinicum, 182
gul/uricum, 184
iulfurosum^ 190
fatinictim, 192
tartnricum^ 1 95
vaUrOinicum, 1 97
AronHina, 109, 200
Arortilinum, 200
.Krujo, 328
.£ther, '2()\
aceticiu^ 204
«U2
INDEX.
Albumen (:is reageui), 30
Alcohol. -JO*;
anivlic, 210
et hylic. 'JiMl
phenyl ic. 1*50
Alcohi'l itJinfUcnm, 210
fu/nin'f^ 301
AlRurolh's pow.ler. 236, 30K
AlktiiieH, Tolumetric ei«timation of, 80
Alk:»loiils, 102
Alk.'inef-pnper. 42
Aimun()<4. ethereal oil of, 440
writer of bitter. 240
Aloin. 21'.
Altiinum, 211
Alum. 212
iron, :^.40
Alumeu. 212
A hi mi nit hydrata^ 214
Aliimihii ^t Amrtoni* .S»///»ArM, 212
// Pt.tntsu ^'«////|!M, 212
Ih/dnLH, 214
SulphiiM, 210
Aluminium hvdnite, 214
sulphate, 21(;
Afu„nnium fit/dnitwitf 214
ituifntum^ 2HJ
Ammonia, solution of, 245
water. 24')
Ammoniatetl cuprie sulphate, 382
ferric rliloriile, *i44
n>er(Mirv. m'.*0
>*uljih:ite of coj'per. 332
A turn- -n 'I Af'f'ih.*^ /.''/'i'/T, 'J'W
ii-nzo 's. 217
lin.iuifiniH. 217
t\,, .'.',„■/.*. 221
t':il<.ri-iii^n, ■_'2->
St ri'. 22«i
/V.'..7.A /'. 227
Su't.^'tiy. 22»<
r'f/^r/ i^./v 22'*
Aii'm<'ni"-('i«'"t'.l»' of iron. 344
ru|ri«' >nlphate. 3:;2
■ \\-y\ iv* chi'ni'l**. 341
-ft-rric citrate. ''4'>
-IVrrii* xiilphate. 340
-lenie tartrate, '-W^'t
-meriMiric c*hlori>le. 3'iO
Aninoninni .u'ctnte. solution of, 3!'7
bt'n2'>:ito, 217
bnnni'le, 217
ivirboiiate, 221
cl.l..ri.le. 223
hytlrate. solution of, 24'^
ici.li.lo. 22'»
molyl»vlatt' (as rengeut). 31
nitrate, 22»i
oxa'ate (as reagent). 31
pho>phale, 227
Ammonium —
>e>.f|ui-carbonnte, 221
sulphate. 228
r>ulphy(lrate (as reap:eiit). o1
f<ulphide (as reagent), 31
valerianate, 22'.»
Ammonium ftf-nzoicHm, 217
hromntum. 217
carh'ifiicum^ 221
rhloratum, 223
j'rrratum, 344
iodnttim. 220
;« M rinticum, 223
martiaOtm^ 844
/litrirum, 22*5
puoyphoricum^ 227
valfnunirum, 221*
.4wv/ Mtrif, 230
Anivl nitrite. 23!»
Amtfifffher nitroiiu, 230
Amylic alcohol, 210
A my hum nitrofum^ 230
Analysis, volumetric, 70
Anhyiiride, chromic, 142
Aniline sulphate (as reagent). 31
Antimoniate of potassium (as reagent), 40
.\iitimonic sulphi«ie. 240
Aniimonii Chforidi, Liquor. 307
<r Poiagfii Tirtrax^ 232
Ox ilium, 2 -5
Oijf fulphuretum^ 242
^u.'phi'iuni, 237
iinriintinfum, 240
S'i.'j'/fir turn. 237
Aniiinoniifus chloride, solution of. 3fC
oxi'le, 23o
oxvchloride, 23n
oxy- sulphide, 242
sulphide, 237
trioxide. 235
A'<t>m'-fiihm tt po*ii*fium tortarirum^ 232
ox'/ddfum^ 230
fulfuratum aurautiucum^ 240
ni'jrnm. 2-7
ruf.^nm. 242
yuiftiT'itum, 242
iuUirirum, 232
Antimony, butter of, 307
cliloriile, si>lution of, 307
oxide of. 23'>
oxy-rhlori.le of, 23r,
oxy->ulphi«le of. 237
penta-ulphide of, 240
>ulphi.ie of. 237
trioxide. 235
trisulpbide of. 237
Apomorpfiin:* Ih/drochhraf, 245
\pomorphine hydrochlorate. 245
A/"-vi..r/rfiifium hi/dro^hloricum^ 245
A'jit 1 Ammomar, 245
Ami/(jd>ili€ nmarx, 240
Cuicix. 300
INDEX.
6i:{
Aqua —
Cfihri 251
DettiUaln, 2r)4
Arg^nti Cftnnidnm^ "ioO
lodidum, 257
Nitnti', 258
Ozidum, 2<)1
Argentic cyanide, 25G
iodide, 257
nitras, 258
volumetric solution of, f'8
oxide, 2GI
sulphate (as reaj^ent), IJI
Argeutum cf/anatitm^ 256
iodatum^ 257
nilricumy 258
oxjf datum, 201
Arseniate of iron, ^{30
sodium. 5'i2
Arsenic, white, I2<>
deteotiun in wall-paper nnd fahricH,
i:i4
estimation in forensic invo!iti<;:ition,
l:{2
test for, Bettendorrs, 1:^,0
Fleitmnnn'.-?. 'MS
Mar-sh'M, :J3, 120
Reinsch'H, 121)
tri bromide, 202
triiodido, 203
Arsenicum alhum^ 120
bromatnm^ 202
iodatum^ 203
Arsenii Bromidum^ 202
lodidum, 203
ArRenious acid, 120
bromide, 2()2
iodide, 203
Arsenite of potasniuni, solution of. 410
Atomic weiphts of elementary bodies, 003
Atrophia, ion, 203
Atrophia' Sufphas^ 205
Atropine sulphate, 205
Atropinnm, 100, 203
ttul/uricum, 2(i5
Auri a Sodh Chloridum, 200
Auric chloride (as reagent), 31
Auro'Natrhtm chloratum, 200
BARBAL0IN.211
iiuric chloride, 208
hydrate (as reagent), 31
nitrate (as reagent), 31
Haru Chloridum, 208
Bnryta murialica, 268
Jian/um chloratum, 208
liases, examination for, 40
Basic birtinuthoiiH carbonate, 273
Ditrate, 270
valerianate, 277
feirous carbonate, 300
Basic —
mercuric sulphate, 380
plumbic carbonate, 453
Beer, estimation of glycerin iu, 372
Bonding of gbisn tubes, 25
Benzine, 32, 200
lUnzhinm, 200
Beiizoate of ammonium, 217
litiiium, 415
sodium, 533
Benzoic acid, 135
Bettendorfs teat for arsenic, 130
Biborate of sodium, 358
Bicarbonate of potassium, 402
sodium, 534
Bichloride of mercury, 373
Bichromate of potassium. 4(>4
Hiniodide of mercury, 370
Bismuth and ammonium citrate, 272
carbonate. 273
nitrate, 270
valerianate, 277
tiixmuthi rt Ammonh Citni.t, 272
Stihcarhonti^f, 273
St/hnitra», 270
Valertana.'<, 377
Bismuthous carbonate, 273
nitrate, 270
valerianate, 277
Jiixmiilum carhonicnm, 27'»
(I (immonh/m rhn'rum, 272
nitrirumy 270
valeriunicitm. 277
liisulphate of quinine, 510
Bi«4ulphide of carbon, 301
BiHul|ihite of sodium. 537
Bisulpliuret of carbon. 301
Bitartrate of potassium. 405
Bitter-almond oil, ethereal, 440
water. 240
Bliick oxide of manganese, 42({
r>leachin<: powder, 20r)
Blue, Brussirtu, 350
vitriol, 330
Bohlig's reagent, 30
Boiling point, determination of, 23
Boracic acid. 137
Borate of sodium. 538
Borax, 538
Bread, detection of alum in. 214
Bromide of amnioaium, 217
arsenic, 2t)2
calcium, 287
lithium. 410
potas>ium, 407
botiium. 530
l>roniine, 270
water (as reagent), 32
lirttviinium^ 270
Urn mum, 270
lirucma, 109, 282
Brucine, 100, '1^2
614
INDEX.
Brucinnm, 100, 282
Burettes, 73
Butyl-chloral hydrnte, 308
Uiiij/lO'Chlorahtvi hydralum, 308
Jiuhjnun andmonii, 246
flADMIJ lodidum, 284
^ Su/pfntit, li8r)
CadmiuTn iodiile, 1284
Bulphate, "JSi")
Cttdminm indatum, 284
gvl/tiricum^ 285
Caffeinii, 2H<>
Cntfeine, 280
Calcaria carbonira pnedj/ifata^ 280
rhlnratd, 2Ut)
hhpochhrosa^ 200
phoitphorica, 294
Calcii /irot.'iiiuniy 287
Oirhnnas, 289
Chfondum, 290
I/i/pophoMphis, 292
ladidum, 29;i
AiV/Mor, 8t)9
P/iosphan, 294
Cnlciitcd inaj^nesia, 421
Calcium hmviatum, 287
caihonicuin, 289
chhtratum, 290
ht/ptfr/iforo.sum, 29(i
hii/i'plii>^j>lioroisuvi^ 292
ioiiiium, 29o
pln'>i)hi>ricum, 29 4
sulfur (I mm, 299
ralcinin liruinide. 287
cailtonute, 289
chlnrlde, 290
hvjux-hlorite, 29r.
Iivpopho^pliite, 292
i.Mli.lo. 29:;
orthopliK.Mphnte, 2!»4
pliosj.h.Ue, 294
Milplrilv (MS reagenl'i, '^2
Bulj.lii.le, 299
Caltuncl. :^.7-)
6'<//x i'/ilnrafit. 29(>
chh.nn.ita, 290
i^ulfurata. 299
CamplMM-, niiniohromide of. .*'iOO
(\im/i/i(ii (J jniitKibrtunatii, I>()0
(' iTH'-siiMjir, volumetric ebliiiiatioii of, 9S
CantliMii.liii, 197, ."^(M)
Cfint/i(irtilinu'u, o()(l
CupJif funrtuinn. 'MW
(\irholic Meid. i;'>9
Carhon )>i-ulpliide, 301
biMiIpliuiet of, 3(M
Curftoiiatp <if ainnionium, 221
bi^tnutli, 27;J
rnlciuio. 289
iron. oOU
! Carbonate —
! iron, hacchnrated, 340
i lead. 453
! lithium, 417
I magnesium, 422
putassiium, crude, 470
I pure. 475
}»urified, 478
, sodium. 543
zinc. 58.^
' Carhotni JUifulphidum^ 301
I Cari/onfum nnlfuratum^ 301
, Caustic potash, 48tj
Hoda. 5'')0
' Ontimeter, 79
Ctrii Oiahs, 303
' Cerium oxalate. 303
Cerium oxnlalum, 303
Ceruftfa, A5'i
Chalk, precipitftted, 289
Chili saltpetre, 500
Chinidiuum^ 502
Jtuf/uricum^ 503]
C/iiuinum, ^05
Chinium. 505
biMilturiatm, 510
J'tTrocilricum, 348
hjfdrobrom atum^ 515
/if/drobmmicum, 515
hi,drochloratum^ 518
hudrochluricum^ 618
sulfurinnn. 520
aridum, 510
tannicvm, 523
Viihrianirum^ 525
Chinoidin, 30 J
C/iitioidiHum^ J J 04
Chloral. .';0.')
alcoholate. 300
hydrate, 305
Cb/oni/i //tfdra.t, 305
Chii'mlum bufi/licum, 308
bi/dri/tum, 305
Chlorate of pota!»»ium, 47S
sodium, 540
Chloridi' of ammonium, 223
aniinionv. solution of, 397
barium. 20S
caleium, 1!90
gold and sodium, 2f't0
iron, 3 II
platinum (as reagent), 40
Hodinm. 548
tin (is reagent), 41
zinc, 5>»9
(Milorinated lime, 290
Chlorine water, 251
rhlorotorm, o08
( '}dnri>i\>rviitim^ 308
Ohromic aiid, 142
(Miromium trioxitle, 142
('hry.'^arohin. 312
Chn/iarobinam. 312
Chrynoplinnic nciil. Sl^
Ciiichonn linrliB, entimntion
607
Cine linn in, 1116
valpUnte, 3IT
CmchoHiilinn. :il»
Cinehoniiimir Sulphat, 314
CincbonMiiie. 3]:t
Citrate of bismuth, 2T0
mill ninmoDlaiD, ^
Itou, 3J3
solulian nf. 4()S
soliKion uf, 40.i
iin'l strychnine, 341)
lilLiiiiii, 41!)
poliiKKiura, 4T9
Citriciii-iJ. HI
CluuilinGM, IK
Cobnltou!! nitrnle (ns rpnaptid. 3
Caahinenl (us itiiliciitnr), TH
CD^fio, 3ltl
CodciDe, 109. 31B
Ciitleinum. HIH
tli/nBo, ■Hfd
C'ltTcine. ■!»>■,
Colfhieina, :i-.'rj
Coiohicine, 107. S'JO
ColcMeinum. HM
Cuoimuu hhIi, r>48
Cmehminnm, TiO-J
tulfurieam, SOS
Conin, liJ-2
Conline! 3^2
Canquliiinu. &02
Cupper, iicetnle nf, '.VIS
Niii iiio-sulphute of, ax-i
oiiile .,r. :i-l'j
Cubic crhlinirter. ill
Oxidrnn, ZiH
Su/plia; ho
Cuprio ncelnte, 328
DxiUe. ■■i-29
EuJplmtr. UO
silTcr, -IM
I
DECANTAKDS, IR
Ueterniinnlion of boiling-point. iS
mFllii>f;-pnint. 23
Diammrinio-hycltic phoMpbritc -*J7
UiRitiiline. 107, 3:i4
PiifiMiniiM. X:H
Iiinirro-^ulpliiileerirDii (ns re.igeni), 32
Diiftilleil wnler. 2r,4
Dinitlpbiile ororbon, 301
Uryii.gprecipiUl<s, il
oxii!
Ktlijli.: n
te of, 3JS
c of, 330
^pA]!RIC^, ciiimlnnlio
' FehliiiK's solution
F'rri Atrliilir. Liquor, ll
Macchuralu; 341)
616
INDEX.
Chloridum, ?A\
Citras. 84 H
solution of, 402
ef Animonn Chhridum, ZAA
el A mm on it Citr/m^ IrJ-jT)
ef Amiiionu Sulphag^ 34^)
el Affit/ionii Torfra^, S4G
ef I^ctaffii Tartra*, '■>47
el Quinititr Citrax, 34 S
solution of, 84S
et Strychninn- Cifraa, 340
ferrocpamdvtH. 350
Hypophofphin, 352
lodvlnm^ 3o2
Lad 09 ^ 353
Ozaia/t, 355
Oxidum hjfdratum^ 356
Perchloridutn^ 34 1
Pernitrattf^ Liquor^ 404
Ptroxidum hydralum, 356
Pho)fj)ha»^ 357
Pyrophoitphas, 35^
^/ 6o(/// Citrate 859
Suhcarhonoi^ 360
Sulvhas, 361
Sidphalix^ Liquor, 405
Valerianae, 'MVS
Ferric acetate, solution of, 399
arKeniate, 339
chloriile, 341
citrate, 343
solution of, 402
dinitrosulpbi'h' (i^ re.ngent), '12
ferrocvmrule, ooU
hyirate, •)5r)
liy[>o|>lioi?phile, 352
nitiuto, solution of. 404
pyroj»ln)sph!itc, 359
sulphate, solution of, 4(J5
vnleriannte, 303
Fen icy'H»i«lp of potasj^ium (as reagent
Ferrocyanide of iron, 350
of p()t."is!*iuui. 4S5
Ferroso-ferric nrseniate, 339
Ferrous carhotuite. 340
saccbarated, 340
iodide, 3 5 J
lactate, 353
(•xalate. 355
sulpliate, 3«J1
Per rum, 304
orKfnicum, I '39
carhotinnm. oliO
forcfioratutn, 340
chloridum, 341
cilricum, 343
ammonia I urn, 345
et atnmontum rhtnroium, 344
el ammonium ciirirum. 345
el ammonium eul/urirum, 346
et ammonium tartartrum^ 346
,J0
Ferrum^
et ehininum eifrintm, 848
et potatiium tartancumf 347
et ttrychninum citricum^ 349
ffrrocyanatum, 350
hypophot'phorotum, 352
iodatum, 352
laeticum, 353
oxy datum hydricum fufeum, 856
oxifdulato-oxydatumpho4phorieum,Z^'t
p/iofphoricum, 857
put v(ra turn, 305
pyropho^phorieum, 359
cwm natrio citricOy 359
reductum, 368
tegqui-rhloratum^ 841
euhcarbonicum, 360
t^uljuiicum, 3t)l
ttirtaricum ammoniatum, 846
voUrianicum^ 363
Filtrntion, 18
Fleitmnnn's test for nrsenic, 36
Float. EnlmanuN,' 74
Floret benzoes, 135
ful/urif, 581
Wwrt, 591
Flour, detection of alum in, 214
Flowers of sulphur, 681
Fluid measures, conversion of United
States, into metric, 606
Fusel oil, 210
GALLIC acid, 147
Gelatin (as renpent), 33
Gelatinized Srtarch (as reagent), 41
Glacial acetic acid, 122
phosphoric acid, 174
GIa>s tubing, bending of, 25
Glauber's salt, 507
Glucose, volumetric estimation of, 97
Glycerin, 370
(i/yn rina. 370
(t/yrinnum, 370
Glycocoll, 13<»
Golden sulphur. 240
Grape- sugar, volumetric estimation of, 97
Green i<»di»le of mercury, 381
Guaiacol, 325
Guaranine, 286
H
EPAR euffuris, 459
Ilydrargyri Jhchh'ridum, 378
Chloridum rorrotivum, 378
w/fr, 875
Cyanidum, 378
Jodidufn Tubrum, 879
viride, 381
• Oxidum flarum. 882
rubmm, 382
Perchloridum, 878
INDEX.
617
Uydrarguri —
Suhchloridiim^ 376
Syftfulphan JiavuSf 386
Hydrargjtrum, 388
aviidato-hichlorutum, 890
amnioniatum hichloraUim, 300
hichlomtum, 373
biiodafutfi, 37*J
chloratum, 375
corrosivHtn sulilimatuTH^ 373
cynnatfnn, M78
iodatum, 381
Tuhrum, 371)
nitricum oxifdulatum^ 385
oztjdtitHin flavum^ 38-
rnhrum^ 382
prncipilatum alfjum, 300
itulfurntnm rtibrum^ 38r»
« w //m r «> M /// ^/f / r 1/ w*, 23 •)
Il^'dr.itc of alumiiiiuni. 214
niiimoniuni, solution of, 24')
biiriuin (ii8 reageiit), 31
cnlcium, solution of, 300
chloral. 305
oxide of iron, 350
potns!*iuin, 480
Kodiuni, 412
Ifytlriodic ncid, 148
Hjdrobromrtte of quinine, 515
Hydrobroinic acid, 150
llydrochiorato of npomorphine, 245
morphine. 433
quinine, 518
Ilydrochluric acid, 153
Hydrocyanic acid, 150
detection in forensic research. 1
ebtimation of, in ethereal oil
bitter almonds, 443
Hydrogen (nasjcent), 33
sulphide, 37
water of (as reagent), 38
sulphuretted (as reagent), 3S
Jlyoscifaniiux Sulphas^ 302
Hyoecyanune sulphate, 302
Jlt/oscifattiinum mljuricum^ 302
Hypochlorite of calcium, 20(i
Hypophosphite of calcium, 202
iron, 252
lime, 202
potassium, 400
sodium, 552
Hypophosphorous acid, 163
Hyposulphite of sodium, 564
61
of
' Iodide of —
iron, 352
lead, 455
mercury, green, 370
red. 381
potassium, 401
silver, 257
sodium, 550
sulphur, 583
zinc, 500
Iodine, 303
water (as reagent), 80
lodinizcd potassium ludide (as reagent),
30
lodinuniy 303
Iodoform, 302
lodoformiunif 392
Iron, 304
acetate of, solution of, 399
alum, 340
and ammonium chloride, 844
and ammonium citrate, 345
and ammonium sulphate, 34()
and ammonium tartrate, 340
and potassium tartrate, 347
and quinine citrate, 348
and strychnine citrate^ 349
arseniate of. .339
carbonate of, 340
chloride of. 341
citrate of, 343
ferrocyanide of, 350
hydrated oxide of, 356
hypophosphite of, 852
iodide of, 352
lactate of, 353
nitrate of, solution of, 404
oxalate of, 355
phosphate of, 857
powdered, 305
pyrophosphate of, 357
with sodium citrate, 350
saccharated carbonate of, 840
subcarbonate of, 300
sulphate of, 301
valerianate of, 803
K
1
NDIGO solution (as reagent), 30
Iodide of amnu ninm, 225
arsenic, 203
cadmium, 281
calcium, 293
AIJUM itceticvm, 460
hicarbonicum^ 402
bichromicunty 404
bidtrlaricum, 405
bromalum, 407
carbotiicum crudum, 470
depuratum, 473
puruniy 475
causticum^ 48t>
chioricuniy 478
chromicum rubrum, 462
cyanatum^ 481
/eiroryanaluvif 485
618
INDEX.
Kalium —
hypenniui'j'inicum^ 407
hypophosplinrosum^ 4^0
iodtifNjn, 401
nUricuntf 4l»4
gulfuricum^ 408
$ulfuro9um^ 490
tartaricum, 501
K^nncs rninertiif, 242
Kreoxofum, 'U-i
T ACsuI/urh, 57H
■*-' Ljic sulphur, 678
Lactate of iron, 535
Luetic ncid, 104
Lactose, volumetric estimation of, 07
Lend, acetate of, 452
carbonate of, 453
iodide of, 455
nitrate of, 450
oxide of, 4. ''^7
red oxide of, 458
bubacetate of, solution of, 407
t«ugar of. 452
wliiip, 453
Lime, carbonate of, 289
chlorinated, 200
hypnpho^*phite of, 202
icdi.le of, 203
phosphate of, 294
water, MOO
Liquor Afnm>>ni:i„ 245
Ainmnnil tinltttixy 307
1(1 tint id, 245
Dz'.tuiii, 240
Aiithuonii rhloridi, •VJ'i
Calcs, WW
r/iluri, 251
J'\rii ac'tici^ 300
chlnrati, 40 1
chloridi, 401
cttrntis, 4(»2
it (Juiniuiv cifrafi.*, 403
e( Qiiiiiatyr riiraiis, 403
nt>rnti.\ 404
jiermtratix, 404
.yi Mjiilrlilorati, 401
yii'i'iiriri oJffthUl^ 40.')
f-i/ffj/iiiH.f^ 405
IIi/'har>ji/ri mfrafix, 4(Mi
rui'rc I iijri/dafi, \{U\
oxi/iiultiti. 3^5
Kill a (I r.^i niro.fi, 410
riiit.>firi, 40H
yittrii C'i»/>(iri, 412
/iffp'ir/i/nro.si, 414
/'<>///.•>.'. 4ns
I'oliiy^u iiTfrniti,'*^ 410
hudrntts^y 4 OH
.Sc/./.v, 412
' Liquor Sod.r —
chlorafiff 414
' chlorinattr, 414
S^»//i hytiratif, 4 1 2
I .SViA/i chlorati, 307
Liter flasks and jars, 71
; Litharge, 457
Lithnryt/nim^ 457
LitUii iiemoax^ 415
Brum ilium, 410
Carbonate 417
07r<M, 410
Salicylag, 420
Lithium henzoate, 415
bromide, 4 Hi
carbonate, 417
citrate, 410
H.I 1 icy late. 420
[jthium btnzoicum^AXb
bromatum^ 410
carbonicum^ 417
eilncum, 419
sal ici/ lieu m^ 42U
Litmus papers, 42
solution of (as reagent), 4]
Lunar caubtic, 258
MAGNEr^lA, 421
calcined. 421
Magnesia alba, 422
carbonica, 422
M.«;^7, 421
MayufKn Carbonax^ 422
(U ill inn, 421
SfflphdK^ 423
Suf/'biji, 420
Magnesium carbonate, 422
mixture (as reagent), 39
oxide, 421
Hulphatc, 423
hulphite. 42r)
Mai/n(si\im ctirbimicum, 422
ori/diitum, 421
.•^tdjuncum, 423
nuljHrosnm^ 420
Manganesic, black oxiJc of, 420
di()xi<!o of, 420
MniHjani Ojidiim nigrum^ 420
Su/jdiUfi, 120
Mai)g:iiious snlpliate. 420
Manipimnn hj/'rroi.tjdii(um, 42*»
C'Xudatum U'lfiium, 420
ifullurirum, 420
Melting point, determination of. 23
Meiciir-aiiimoiiium chloride, 300
.Mercuric chloritje, 373
cyaiiide. .'178
iciilitle, 37".'
with potassium iodide (as re-
agent I, 40
nitrate, solution of, 406
INDEX.
619
Mercuric —
oxide, 882
oxychloi-ide (as rengent), 89
siiiphide, 88G
Mrrcurivn dulcis^ 375
Mercurous chloride, 376
iodide, 381
nitrate. 385
Mercury, 388
ammoniated, 300
nmmouio-chloride of, 390
binioilide of, 379
cytiiiide of, 378
oxide of. 382
perchloiide of. 373
pernitrnte, solution of, 406
proioiodide of, 881
subchloride of, 379
Rubiiitnite of, 885
sulphide of, 230
Meta-dioxy benzol, 526
Metu-phosphoric acid, 174
Methenyl iodide, 392
Methyl propyl-phenol, 583
Methyl- theobromine, 286
Metric measures of capacity, conversion
into United States fluid measures,
(>06
weights, conversion into troy weights,
tiU8
Mild chloride of mercury, 375
Milk, sugar of, volumetric estimation of,97
of sulphur, 578
Mineral kermes, 242
Minium, 458
Molybdate of sodium (as reagent), 41
Monobromated camphor, 300
Morphia, 111,430
Morphina, 430
Morpfiinif Aretas, 432
Ui/drochhraSy 433
MuriuK, 433
Sulphas. 434
Morphine, 111,430
acetate. 432
estimation of, in opium. 485
in tincture of opium, 439
hydrochloraie, 433
sulphate, 434
Morpliium^ 430
acftictm, 432
hydrochloricurn^ 433
sulfuricum^ 434
Mucilage of starch (as reagent), 41
Muriatic acid, 153
Mustard, ethereal oil of, 443
NARCEINE, 111
Narcotine, 1 10
Nataloin, 211
Natrio kalium tartaricum, 483
Natrium aceticum. 530
arsenicum^ 532
bfnzoiatm^ 538
htborimmy 538
bicarhonirum^ 534
bisul/urosum, 537
bromatum^ 539
carbonicuTii, 543
cansticum^ 550
chloratum, 548
chlorirum^ 546
ht/dricum, 550
hi/pop hosp ho roium^ 552
hj/posul/uroaitmj 554
iodatum^ 55r>
nitricum^ 560
phosphoricum, 561
pyrophosphorirum^ 564
saUrylicum^ 505
santoninicum^ 566
subsul/uronum^ 554
gul/ocarbolicum, 570
iulfophenolicum^ 570
su/furicumj 667
sul/urosum^ 569
Neesler'M reagent, 40
Neutralization, volumetric analysis by, 80
NicotinOf 439
Nicotine, 109, 439
Nicotinum, 439
Nitrate of ammonium, 226
bismuth, 276
iron, solution of, 404
lead, 456
mercury, 385, 406
potassium, 494
silver, 258
sodium, 560
strychnine, 576
Nitre. 491
sweet spirit of, 571
Nitric acid, 165
Nitrite of amyl, 230
OIL of bitter almonds, 440
mustard, 443
Oleic acid, 171
Oleum amygdalse. irlhcrrum^ 410
siitapis iPfherfum, 443
Opalescence, 18
Opium, morphiometric assay of, 436
Ortho-oxybenzoic acid, 181
Orlho-plio.<phoric acid, 174
Oxalate of cerium, 303
iron, 355
Oxalic acid, 172
standard solution of. 82
Oxidation, volumetric analysis by, 88
Oxide of antimony, 235
copper, 329
iron, 356
620
INDEX.
Oxide of —
lead, 457
magnesium, 421
manganese, 420
mercury, »382
silver, 201
zinc, 501
Oxychloride of mercury (as reagent),
Oxy-propionic acid, 104
PAPAVERINE, 110
Paper, alkanet, 42
litmus, 42
plumbic acetate, 42
turmeric, 42
Pearlash, 470
purified, 473
Penrasulpbide of antimony, 240
Percliloride of iron, :^41
solution of, 401
of mercury, 373
Permanganate of potassium, 497
Pernitrate of iron, solution of. 404
mercury, solution of, 400
Peroxyliydrate of iron, 360
Persulphate of iron, solution of, 405
Petroleum ether, 209
Phenic acid, 139
Phenolphtalein (as indicator), 78
Phenylio alcohol, 139
Phosphate of ammonium, 227
calcium. 294
iron, JS57
lime, 294
sodiiun, 501
Phosphide of zinc. 59o
Phosphoric acid, 174
Phosphorous salt (as reagent), 39
Phosphorus y 445
J*hiisosti(finiiUf Salin/las, 449
Physosligujine, 110
salicyl;ite of, 449
Physostiguiinwn .sal(ci//f'-i(/n, 419
Picrotoxin, 107, 449
J*icro(oxmuin, 449
I'llocarpinii Ili/drorhloras, 451
Pilocar[)iMe hyirochlorate, 451
Pilocarpinwn ht/drorhlorirttm, 451
Pijjf'rina^ 451
Pi peri ne, 451
Pipettes, 71
Platinic chloride (a« reagent), 40
Plumhi Acftas, 452
Carhonas, 453
lodidum, 455
JVitnis, 450
Ozidiim, 457
riihnaii^ 458
Subaretafis, Liquor, 407
Subcarhonas, 453
Plumbic acetate, 452
39
Plumbic — •
carbonate, 453
iodide, 455
monoxide, 457
nitrate, 450
plumbate, 458
subacetate, solution of, 407
subcarbonate, 453
Plumbum acftirum^ 452
carbonicum, 453
iodatum, 455
mtricum, 450
oxy datum fuxcum, 457
rubrum, 458
Potash, crude, 470
pure. 475
purified, 473
Potassa, 480
solution of, 408
sulphurata, 459
Polassii Aretag, 400
Bicarbonate 402
Birhromas, 404
Bilartras, 405
Bromidum, 407
Carbonas crudus, 470
depuratm^ 473
purus, 475
Chloras, 478
Ci/amdum^ 481
Ferroeyanidum^ 485
Hydras crudus^ 488
purus, 480
Ilypophosphis, 490
lodidum, 491
Nitras, 494
Per many anas, 497
(t Sodii Tartras, 483
Sulphas, 498
Sulphidum, 459
Su/phis, 499
Sulphureium, 459
Tartras, 501
Potassioantimouious tartrate, 232
Potassio-ferric tartrate, 347
Potassiu-mercuric iodide (as reagent), 40
Potassium acetate, 400
and sodium tartrate, 483
antinioniate (as reagent), 40
arsenite, solution of, 410
bicarbonate, 402
bichromate, 4ti4
standard solution of, 91
bitartrate, 404
bromide, 407
carbonate, crude, 470
pure. 475
purified, 473
chlorate, 478
cyanide, 481
ferricyanide (as reagent), 40
ferrocyanide, 486
INDEX.
621
Potassium —
liycirnte, 486
standard solution of, 87
hypophoMphite, 490
iodide, 491
mercuric iodide (as reagent), 40
nitrate, 494
permanganate, 497
standard solution of, 89
prussiate, 485
sulphate, 498
sulphide, 459
sulphite. 499
sulphuret, 459
sulpho-cyanide (as reagent), 41
tartrate, 001
Precipitated carbonate of lime, 289
carbonate of zinc, 588
oxide of mercury, 3H2
phosfih.ite of lime, 294
sulphur, 578
Precipitates, 19, 22
Precipitation, 18
volumetric estimation by, 98
Preliminary examination, 44
Prussic acid, 159
Pyroborate of sodium, 538
Pyrolusite, 420
l*yrophosphato of iron, 359
in scales, 359
with citrate of sodium, 359
of sodium, 564
QUICKSILVER, 388
Quinia, 505
Quinidia, 502
Quinifiina, 502
Quinidinas Sulphas^ 503
Quinidine, 502
sulphate, 503
Qiiinina, 505
Quininff Bisulphas^ 516
I/t/drobromas, 515
Hydrochloraa^ 518
Muriiis^ 518
Sulphnn, 520
Tannas, 523
Vft ler tanas , 525
Quinine, 505
blsulphate. 516
ferric citrate, 348
hydrobroraate, 515
hydrochlorate, 518
muriate, 518
sulphate, 520
tannate, 523
valerianate, 525
Quinoidine, 304
Quinoidinumy 304
REAGENTS and reactions, 26
for alkaloids, 103
Red iodide of mercury, 379
oxide of lead, 458
of mercury, 382
precipitate, 382
sulphide of mercury, 386
Reduction, volumetric analysis by, 88
Reinsch's test for arsenic, 129
Removing precipitates, 20
Resorcin, 526
Resorcinum^ 526
Rochelle salt, 483
SACCHARATED carbonate of iron, 340
Saccharose, volumetric estimation of,
98
Sal timmoniaeum, 223
tartaric 475
Salicin, 527
Salicinumt 527
Salicylate of lithium. 420
physostigmine, 449
sodium, 565
Salicylic acid, 181
Salt, common, 548
of tartar, 475
Saltpetre, 490
Chili, 660
Santonin, 528
Santoninate of sodium, 566
Santoninufny 528
Seignette salt, 483
Sesqtii-carbonate of ammonium, 221
Silver, cyanide of, 256
iodide of, 257
nitrate of, 258
oxide of, 261
Socaloin, 212
Soda, 550
solution of, 412
Soda-lime (as reagent), 41
Sodii Acetas, 530
Arsenitix, 532
Benzoat, 633
BirarhonaSf 534
liiaulphis^ 537
Boran^ 538
Bromiduniy 589
Cdrbonas, 543
Chloras, 546
Chloridum, 648
Hffdras^ 550
Ht/pophofphi9^ 552
JJi/posulphUf 554
lodiduniy 666
Nilraa, 560
/*ho*pha8j 661
Phosphite 561
Pifrophosphas^ 664
Salieylatj 665
622
INDEX.
Santomna», 56C
Sufphas^ .">i)7
Sulphis, 5G0
SuiphocarbolnSf 570
Sodium AcetAte, 530
arseiiinte, 532
beiizoate, 538
bicarbonate, 534
bromide, 530
carbonate, 543
chlorate, 546
chlor-aumte, 266
chloride, 548
hjdrato, 550
solution of, 412
hypochlorite, 414
hypopbosphite, 552
hyposulphite, 554
standard solution of, 94
iodide, 556
molybdate (as reagent), 41
nitrate, 560
phosphate, 561
phosphite, 561
pyrophosphate, 564
salicylate, 565
santoninate. 566
sulphate, 567
sulphite, 569
gulphocarbolute, 570
tetraph'i-sphrite. 564
thiosulphite, 554
Sodiwii tart'iratmn, 5i:*3
Solution, 17
ulcoholic, of ammonia. 246
of ethyl nitrite, 571
Ammonium ucetate, 397
liy 'Irate, 245
antimonious chloride, 3'J7
calcium hydrate, 3'j'.»
chlorido of iron. 401
chlorinated soda, 414
chlorine. 2')1
citrate of iron. 402
and quinine. 403
Fehling's iw-i rea^jent), 32
ferric acel ite. 3'.»y
chloride. 4<»1
citrate. 402
and '{tiiniue citrate, 403
nitrate. 4<)4
sulphite, 405
indigo ' a?* reajjent), 30
litnui-? iX-i reapeiit , 41
mercuric nitrate, 406
mereurous nitrate, ;;85
pernitrate of iron, 404
of mercury, 406
persulphate of iron, 405
pota'isa, 40S
potassium arsenite, 410
Solation —
potassium hydrate, 408
soda, 412
sodium hydrate, 412
hypochlorite, 414
solid bodies, 48
subacetate of lead, 407
triplumbic acetate. 407
Spirit of Mindereras, 397
of nitrous ether, 571
SpirituM, 206
JEtheriM nitroMt^ 571
Ammoniif 246
Nitri dulcit, oil
nitroso-acthernu, 571
Staunoos chloride (as reagent;, 41
Stihii chlorati. Liquor^ 397
Stibium oxydatum^ 235
tul/uratum aurantiacum, 240
niffrum^ 287
ruheum, 242
Strychnia, 574
Strychnina, 574
Strychninie Xitras^ 570
Sulphate 578
Strychnine, 109, 574
ferric citrate, 349
nitrate of, 576
sulphate of, 578
Stn/rhnium, 574
ferrO'CHrimm^ 349
nifricum, 576
ful/urirum, 57 S
Subacetate of copper, 328
lead, 407
Subcarbonate of bismuth, 273
lead. 453
Subchloride of mercury. 375
Sublimed sulphur. 5**1
Subnitrate of bismuth, 276
mercury. 385
Subsulphate of mercury, 386
Succinic acid, 182
Sugar of lead. 452
Suj^ars. volumetric estimation of. 96
Sulphate of aluminium, 216
ammonium. 228
atropine, 265
ca*lmium, 285
cinchonidioe. 314
cinchonine. 317
conquinine, 503
copper. 330
hyoscyamine, 392
iron. 361
and ammonium, 346
magnesium, 423
manganese. 429
mercury, 38»l
morphine, 434
potassium, 408
quinidine, 503
INDEX.
623
Sulphate of —
quinine, 520
Bodiuni, 0G7
Rlrychnine, 678
zinc, 594
Sulphide pf aotimonj, 237
hydrogen, 37
mercury, 386
potassium, 459
Sulphite of magnesium, 426
potasisium, 499
sodium, 569
Sulphocarbolate of sodium, 570
line, 597
Sulphocynnide of potassium (as reagent),
41
Sulphophenylate of sodium, 570
line, 597
Sulphur, flowers of, 581
golden, 240
iodide of, 583
precipitated, 578
sublimed, 581
Sulphur auratum antimoniif 240 #
depuratwn, 581
iodatum^ 58o
tot urn, 581
prit'cipitafwn, 578
Hublimatum, 581
Sulphurated nntiraony, 242
lime, 299
potassa, 459
Sulphuret of potassium, 459
Sulphuretted hydrogen, 87
Sulphuric acid, 184
Sulphurous acid, 190
Sweet spirit of nitre, 571
iSyrupua Ferri iodidi^ 353
T ANNATE of quinine, 523
Tannic acid, 192
Tannin, 192
Tartar, cream of, 465
emetic, 232
Tartarated antimony, 232
Tartaric acid, 195
Tartarus depuratus^ 465
witronatus^ 483
stibiatus, 232
Tartrate of antimony and potassium, 232
iron and ammonium, 346
and potassium, 347
potassium, 501
and antimony, 232
and sodium, 483
Teriodide of formyl, 392
Tersulphate of iron, solution of, 405
Test, Hettendorf's, for arsenic, 130
Fleitmann's, for arsenic, 36
Marsh's, for arsenic, 33, 129
Keiusch's, foe arsenic, 129
Test-papers, 41
Test- solutions, 29
Tests, chemical, 48
Thebaine. 110
Theine, 286
Thermometric tables, 604
Thiosulphate of sodium, 554
Thymol, 583
Thymolum, 583
Tincture of opium, morphiometric assay
of. 439
Triatomic propenyl alcohol, 370
Tribasic ammonium phosphate, 227
calcium phosphate, 294
sodium phosphate, 561
Triplumbic tetroxide, 458
Trisulphide of antimony, 237
Troy weights, 79
conversion of, into metric weight9,608
Turbidity, 18
Turmeric paper, 42
solution (as reagent), 42
Turpethum minerale^ 386
VALERIANATE of ammonium, 229
bismuth, 277
iron, 363
quinine, 525
zinc, 598
Valerianic acid, 197
Veratria, 584
Veratrina, 584
Veratrine, 109, 584
Verdigris, 328
Vermilion, 886
Vinegar, 117
Vitriol, blue, 330
white, 594
Volatile oil of bitter nlmonds, 440
mustard, 443
Volumetric analysis, 30
WALL-PAPER, examination for arse-
nic, 134
Washing bottle, 19
precipitates, 19
Water, bromine (as reagent), 32
chlorine, 251
distilled, 254
lime, 399
of ammonia, 245
of bitter almonds, 249
Weighing, precipitates, 22
Weights, conversion of metric into troy,
608
conversion of troy into metric, 609
table of atomic, 603
White arsenic, 126
lead. 453
precipitate, 390
624
INDEX.
White-
vitriol, 504
Wine, estimation of jflycerin in, 372
Wood- tar creusote, 324
YELLOW iodi.ie of mercury, 381
oxi<ie of mercury, 382
prusHi.ite of potassium, 486
Hubsulphate of mercury, 386
z
INC ncetate, 580
bromide. 587
carbonate. 588
chloride, 589
iodide, 500
oxide, 501
phosphide, 503
sulpiiate, 504
sulphocarbolate, 597
sulphophenylate, 597
valeriauate, 598
Zinci Acetas^ 686
liromidum, 587
Carbonax prupcipilaluSf 588
Chloridum, 589
lodidum^ 500
(fxidum, 591
]*/ioxphidum^ 593
Sulphas, 504
Sfilphocarbolas^ 597
Sulphophcnylas, 597
Vahrianas, 508
Zincnm aceticum, 586
hromatum^ 587
carhonicum, 588
chloralnm^ 689
todnturHy 590
oxi/daium, 601
phosphoratum^ 503
fulfoearbolicum,, 597
sulfophenylicum, 697
xul/uricum, 604
vaUrianicum, 698
2%w JooJt t5 the prop:
COOPER MEDICAL COI.L. : _•
SAN FRANCISCO. GAL.
Ofr/f/ ?V» not fo he tv'#i'» ^i /* • :?. ^ -^
1 1
THE END.
HENRY O. LEA'S SON & OO.'S
(LATS HBNBT C. LEA)
MEDICAL AND SURGICAL
:pxjiBiLjiOwA.Tioisrs.
In asking the attention of the profession to the works advert ined in the following
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PROSPECTUS FOR 1883.
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Henut C. Lfa's Son & Co.'a Pcblicatiohb— { 7Ae Medirnl Sm
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TUE AMERICAN JOURNAL OF THE MEDICAL SCIE5CES.,
Edited by I. MINIS HAYS. A.M., M.D.,
>-EH THRXK HUNURKD OCTAVO rAQKS, rUU.T ILLOflTIUTBR,
oingihe sixty-fonrlb consecutive year of the pulilkftlionorihe AiiMMAl
r*U ibe pulilithen annotince. with no little pride, (tiat its proejiects of continoM
IS and attractiveness never were farigbler. Heing the cnly periodical in iM
Henry C. Lba'b Son & Co.'a Pubi.icatiosb— (^m. Jonrn. Med. ScL). S
English language ciipnble of presenting extensive und elnborale HrliuleH — tho rorm
ill which the most importnnl tJIscoveriPB Imve always heeii comnraQit-ated to Ibe pro-
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During 1883 Tqe Jourkai, will couliaiie to present those Teatures which have long
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Mbdical SaiGNCRB, which, being a classified and arranged condeneation of important
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Thesubamptionprii^ctothe Amkmcan JoDHNALur theMkdicai. SciRlfCRB hsa
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or Medical Sciknoe: Con-
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luKJ'.I'l>'"'H>"<<7i Sargi-rT, 0 bel« trie ■. Medici 1
the AeeEDlunlitiD »fid BljmaloBJ «r
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<ed, aod irr; greatl; Hod-
ighlj Re
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Cloth. SA SO ^
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Utcd forihe wurh hu enabled him.lnnptliti
atie, unlit at length it has iKilnad Ibe poi"'
T the lanfrnage is spoken.
Ion of the present edition Co maintain t hit •D''^^
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t. Hunib»>liIlioii
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oblalnel.— firUli* Med J-urw.Oct.ai, ISTt.
fjoblyn (richard d.), m.d
■"a dictionary of tue terms used in medicine and-
TltK COLLATERAL PCIEKCBS. Beiised, with nnmerout idditloni, by Iilxp n^ia.
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ffOD \YELL [O. F.). F.E.A.3.. frr.
A DICTIONARY OF SCIENCE: Comprising Astronomy, Chev
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Henm C. Lka's Son de Co.'s Prm.icATioss— (^m. Joum. Jtfi-tl. Si^'.). 8
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and impartiality, and will contain elaborate reviews of new wnrks and topics of tbe
day, and unmernns analytical and bibliographical notices by competent wril«r«.
Then follows tbe QoARTRni.T SDlMAitr Of Improvexektb avd Discovkbieb IH ths
Mkdicai. Scibhcbb. which, being a clasaiflud and arranged condeoeation of importjiut
articles appearing in the chief medieai journals of the world, furnishes a compact
digest of medical progress abroad and at home.
Thu subscriptiou prlee to ihu Amkhican Journal ur tiik Mkdical Scirkcbs has
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I
I
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Henbt C. Lba'8 Son & Co. 'a Publioatiokb — (^Anatomtf};
rawfngB bf ^H
• AnTaoRaad ^
/IR^r IBEyRD. F.R-S..
ANATOMY. PESCRirriVE AND SURGICAL. The Drawfnga by ^
a. V. CiRTBR, H.D..iiDdDr.WisTiitraTT. Ths DiaHetiaDijoinllyb; th« AnTaoaa^ '
Dr. Ci>T«K. With an I Dtrod notion OD OcnerAl Aaiitamj nnd Daielopnianl bf T.
iIi>i.Hi«, HA-SiirgiDD to Si Scorge'i Hnspi.,-!], A New An)Prlc*D. from th* Eigbtfa
KDlirgcd and Impro^gd London Edllion . To wbloh \t nddad the Sacnnd Anerlpmn ffaiQ tb*
InMrt EnglUh Kdilion of ■' LtKDUinss. Mipicii, jmd 6iiiieit.'AL." by Ldtiicb UutnuK.
F.R C.S ,aiilliar of "UDtDm Osteolagj." •' A.Miinu»l of Disisi-tioDi," otc. In oq*
m>gDi<l°>otiiopgrial dbIsto YDlamg of 9D.1 pkgee, with ill lugs tod tUbnralccnErv-
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The kuthor bu undesTorBd inlbiiwork to cover a niurc (itendcjirsngeoliaojMiEthHil Uaui-
umatj in tba ardinktr teit-books, bj glTiDg nut onlj I be details neoMMrjfortbc atadent. bat
■Uiitba appllciitianaf thoiedeUiUin (brprBcIiccoI'mediginssndiiirgcrjr, tbutrpadsriag it botb
• gaid* r«r tbdoBrner and an admirablo woikofTerfrfDcc for tbe Mti« practUionet Tba tv-
rnriOK* tof a ipeoial featnre in tbc work, many ef lh»m being tbe liic of natnre, neail; all
original, and baviag Ibe namei of tbe Farioni pirl.^ prinlvd on the body of th«eut, in place of
llsareiorrererenDe.iiithdegcHpli'ins at tbe root. Tbayiba*' forin acaniplele.i.nd iplendid aerial,
whiab will graatly aisiitthe iiodtDtin obtaining n cleur idea uf A □atom}', and will alio (arrate
refreah the memory of thoae nho may find in tbe Fiigmciei of praotieetheaeoesilCjrof rcoalllBB
the datoili of ibe dliMcling room. Combining, aa it doea. a onnplel* Atlas of Anatomy, irllb
A tboroBghlieatiaeon ajKlHm:ili(i, datnriptive and applied Anatom)'. th« work wilt b* [ooodM
great atriioe loull physiciant who reaeivetladentiin ihsir oAaei, relieving both prMcptor and
pupil of moob labor in laying tbe groand work of a thorough medioul edaealioa.
To Ibe preaant edilion bna been appended tb> rroenl xnrk by Ibe diilinguitbed anatoniat,
Mr, Luther Hnlden — "Landinarha. Hedieal and Surgionl"— whiob givu in a clear, oondeaaed
and tyalemalia way. all rbe information by whiob Ibe praetiiioner onn determine fri>m tba ea*
ternalanrfaeeorihe body tbe poailion of internal pnrU. Thnaoomplete, tbe work, it iabtllered,
will rnrniah all tbe aaaiataneethntenn be rendered by typeimd illualralion in aDBl'iioical ttndr,
Nolwilhalanding (he Increaae of aiie, amootiling In ovar lOD pageeand ST illantratiou. 1 1 will
be kept, aa beretofDre, at ■ piioa rendaring It one of tb* cfaeapeet Workc alar oSared to lh«
Am^rinan profeaiion.
annpUi* treiilH arallibis lo amivtlean iiBileniB, ' elflil edtlinae itiMafh wkiat II liaa paaiad, vaali'
■aaioiar. (boal all llial eaa be laanbl oa geaetBl I addlllaa of Huldi-a'i ■'Laldmarkt" irlll nakaltal
and •peelal aaaiony. irblla lii Irexnenl of aaih llndlapaaHble to Iha prastiiloDai of Bedlda* nM
ngloa.rroia ■ aargleal polal gf .lew, la the lain, snrgeryax II )i*- Beea herelorDrela Ibealadaal. «i
abloeetlualiTHr Ilnld*a,la all ihal will beei-ee- rafardt eomiilateaeaa, eaat rtf rerereaea, atinUi
tUI lo Ibem la praellee.-Okfo IT'dleul Bir^rdir I haiulr agd oheapa«», 11 hat ao rlral. It* itC
a•w^*lt'*°'l'''Sf■"^^^"«mIaB hV'a'Vear(ji'''"fT-— ^^
TTOLDUN (LUTHER). F.R.C.S..
LANDMARKS. MRDICAL AND SURGICAL. So.roml American.
from tbe Latett Reriaed Engliab Edition, with addiliuna by W. W. KiKi. U.D., Pnifea.
aor of Arliatio Anatomy In the Pen nry I can in Academy of th* Pine Aria, formerly l,aa.
turer od Anatomy in tbe Philadelphia School of Anatomy. In one bandaoaa Urns.
Tolome, at about MO ptgea. Cloth, tl.OI). (Jihi Rtvif.l
Lad palpable, of iba bojy, w
lad phyaiologieal faeta u ij
0 Mra il by b<
tJJUlTH IBENRra.). M.D.. aiiH flORNER [ WILLIAM B.),M.D.,
AN ANATOMICAL ATLAS; Illustrative of Ihe Structure of Ui«
Haman Body. In one voin ma. large imperial sola to, oloth, with abonl (Ix bnadred
MLLAHTH STCDBHT'S OOIDK TO BDROIGIL, HafjTSaORHrSnAKDBOOBOr ASAIMMT A»
._ ._ ..... .p„p,,|,j| fUYsiOLOOr. SeemidBdUI. " "
CLELl
'lib eairaTlafa oa | rsyalltmo Tal,,wlllil90w<iodagl> CI*(b,»lN.
"•■ ci"ii,«» laoasKiiB BPBf;i*L*ii»Toin asd Binob-
rHB DT8SBCTI0B — - --•-■■-■ - -
Hkhki C. IiEA'8 Son k Co.'b Poni.iCATio.is — (Analomtf).
A hLES (H.ARRIS0.\'). M D.
ASYSTEMOFDUMAX ANATOMY: INCr.miNO ITS MRDICAL
an.l gurgiTi>R>)D(i«n«. yorlha tTi»nrPriiDmii>ii«ri»nd Slndentanr Hedtcioc With iiii
InltoduDtorjChkptsrnnlliilnloc} B;E. 0. eaiKKRPRAKii. M D .Op^tbarninlociittotbs
PfalU. Hoop In »iir inrgt mil h^xiiliiDine qoftrtn thIudic nr ihaiit (tfld dDnbli-Dnlamiiad
puKHH, widi 3S0 illa'tnttinni on lOU Itthoicrnpliio pliiei mnn; uf whii'b or* in aolun,
itnd about 1^0 BDRtaiinga in tb« t«il. In lix Stallort, riub in ■ porifglia. S<«tJon I.
lliaTOLflST tJ«ii fiN</y). SniioB II. Bokvb Ai>n Joibtb (JhiI Rh^«). SeclioD III.
Mkbci,n« «xd Fascia U-u Rmdy). eteMSa IV. Autikibi, Vbihb akd LvHrflATica
[Ktartf Rtadit) Btotlon V. Nektqdb BmtBB (/. i>n<»). Smlioc VI Oboans or
SkBIB, O? Dlfl»»tl011 ASD GlBlTU-tlBUAItT OrSAIIB ( (" J"""). Fill!' ftt McUon,
SS iO. For m/* Ay iMiteriplivn ou/y.
iqulrtmnnU nt tb* itndcnc und lb* pr»-li(i<in(r of mtdielnr
link ta DFrdnil. iiiBiinuah m no trfitita, u Ikr M ba known,
iriptifiiirih* lubjcot. BijattionLla prexnlBliDnotaash annLoi
rbtitialud
Ma*pl*bla eiprepilon of tbs pp«Banl ttnls nf th« tcianca of a
ttait cnn ba ninda apptienblc In lh« medloBi iirt. nnd wbieta
porlmiD'. whUaoinlttiDKnulbingorTctlua WallniHl niiilici
for axiftcnec in a ouuntry wbera mntt anrgaani nra f^anan
faw ganaral pTADlitiuiKn irhn bB>>( no InlaTeiil in ■argary.
Among olbar mattarj. Iha book will be fnnnd Id Buniati
ing
oiltiai
Olion
praianting ■ ti
anndia in Urina : oblcb will
iiU«mv; ahlrh Hill skdIuJc ni
liU tbni ambtao* all ut •nrgixal Im"
la, — irn»ld nppear In hara an ainuw
] prBOttlionata, and wbar* iham an
an rlobornte d»(er<p(lnii nf tha tia-
I of tba darptr
tba dulgn of
>adTi>[Bppliad*a>i<taif
PBDpli'dlailit
B all prMtdlBi j aiiiijaaL Tba depi
a ^t,UiW,"j o«i'i,'i.'«riro«'Vb'r»n"
Mliaalnl aaija inllxoa a>< oiade ollb iiw
Tbialadoiatir aLUiil
t»l>»ri»,b]r(i<i
• rwUbll Tha Ilia-
a b'KaHoaa. nt Iba !!•■. of ib* t>rt»aa eF.aa.. aou '. imlaU I. lb. •Tc^itf oaiil* -I It* aa.lt«l ul.i-
l'jqn*llag(si»«.wblrtlllBalr«ialln"liWKlllailoouf I ulaa akId iho.a iI IbenKaiAllaf >giiaui. la r>'l.
lloa us lb* Bubo aad Julala aha*. <io Morr paga ><■■!- on •rBlaj irlileh Ihay m-j aafar h«a
••Mt8e».ri>T. Alias', vide I«itbIb( ■iid)adltl.t.i. ib.i'iKkl tafur, ai* •» -.11 p.—nnd fnr lli.lr wa-
atlrailou or Biaiailal. anbtiia»lB|i ay Ita ti-rt hrh- ' udarailua. ti l> a iratk iiblcb l> dsailaad t> ba
Ba». Tka pUia* an bianlirui •p>tlai>a' of wmlc iha bail of lia klaH la aar lAOfa*^ — JTiiKniJ
Ipl-LIS lOEOROR fiyEH)
DEMONSTRATIONS OF ANATOMY; llHiig a Oiiirto lo Uio
ladg* of tha ilnainn Bodj b; Disaeslton. Uy (IliiMinB Vinitii Etr.tia. Ginarllna I
nf Anatonj tn Unlvpnti; Collaga. Londnn. rrom ibv Rithth and I(-Ttfa<l LoO'
tlun. In ana vary handiiama ubUvd •olumi of orar Tail engai, itiih 7*9 lllna
Cloth, un I laatbar, >&.».
Ibrsaub algbl ad
ItriLSON lERASHaS) F.U
^'^A SYSTEM OF HUMAN J
t-HiMv.itai.ina" """
ANATOMY, General and Speulal. Etitied
if Anil Burglflnl AnataiDjin tha Uadkal Col-
iind ninrtj.isvan angradnga on wood In
rer dgO pagai. Olotb, II , laathat. ti.
Hbnkt C. Lka'b Som & Oo.'a Pcbuoaiioms — {Phtftiotoyt/}.
fkALTON (JOHN C),
M.D..
nyHoliinltiHuCalUgtaf PhgtUUmtajid Surptonjt, /fna r»r*,**,
A TRKATISK ON HUMAN PHYSIOLOGY. Designed for the n
oretDdcntrsiidPriKitUiaDtraofllcdisin*, 5cT<nlhBdltioa. (horaagbljravitrdud rrwi
tan. In one vrr; bciotiriilogtaTn Tolnnir, of 732 pngcf, oilb SSS biiatiltll ragrKiian
OD wood. Chilb, %b Oil; tealber. CSDO; yttj "ittnAtomt hsIF RuHii, niHd hind*, SA &0.
(./h.i RuiJy.)
Tb> rfpulnllun whiok tbin work bu aeqnited. ae n gnmpaet nod eontrnicnt lammar; of th*
tDiut idTinred tnaditiun of bninsii phfti^o;;, rinden il on]; ne««iiiry lo aUiM thai Ibf kk.
Iher bai •Midntroilj labored M render Iba pment edilion wwlhj a oenttnuaac* of lh< nr . _
ftiiDr Becardfil la previoai iunoi, and Ibil tyttj oara ba« baen baaluwed lipnn lb* t/pngrapbU ■
cal axttallvn totnakall, ai barelofuia, Dneoftbe hnndiomeel ptoduetiuni oFlha A "
Tlieniill<»rPiuf.D*ll(.B'>iMI busk, till •lu.'D L tiauar aud moia ■Itrar'ITe ll|bl *<
!ro™,*M- ■
rtAHPBNTKH [ WILLIAM B.), M. It., F.K.S., F.O.S., F.L.S..
*^ Rtffl^rartnOMfTtuii of lumttem. Me
PRINCIPLES OFHUMANPHYSIOLOOY;Eiliti;(!l>yHFNBVPowB»,|
M.B. Loiid..F B.C.G.. R«am<u(ria Halarul Sciani-ei, Univer^itj of Oxford. A S*w I
Amaricaofiom the Gigbth Revised and Enlarged EDgliab Edition, iritb Nolo and Addl-I
tioni.bjFBiic II O. Smith, U.D., ProrcasorDl tbelnstitaKtcf UadiciD*iD thaUnivai.
«it7 af FvnBffUanii. ato. [noaa verj larga aBdhaDdtDmcoolavoTolatB«,of lOSUpkfat,
wlih two plates and 3T.taDg«. on wood. Cloth, $6 SO; Itatber, |ll&0; balf HnaaJB, fT.
• daJliblfi
ThL. Kilboak of pkjilalonr bai a)vi , _^
gml taioflM. lb* olair dHaripiiun, lb* —ikU
iDode ul wrlilnt. lb* baudMma black-fnitBd wm#.'M
auAlj. TliaHihMBowraMha . . . _
ttrofWluB.— C'fftai'ii Mwditat and ttur^uit Jtm^
uliofall, l'alliowb»j« raacaor Bhrdolofjr, upot
l'bV°l*>t'r.rM7fa*bt a"b«*fur* gibarogTr' Tb°a
■a (tub ail 1 1 lea. la lOBalnmloi. weaaaclTaoamt.
work on pbjralalsVj-ta •isFlaDcaigi ibat.lalkernir-
ail Hl-e ollb* word, la tba prodnctliB of* ptallOHi-
• ntruveDu* pliyt1a1ufl>t.brae|1illl ap at roll*
(• aoild baaipaelad. If »l doited, la Iba lUadatd
»( osi k>o«i.t«of
Il vllt daHrrailTf m
•■bjeet at
It ^n^albluf^Bl
aBtij'ba
aabl*sl.pnKHUr nttalB a( Iba fulDiw of loftraii
II irllleonrn.aDd naU'alanrdvf Iha awaiw*
nbkb II 0111 Ibm ba ftnnct •latwL— £>■•«*■
U itatlacuMiid xlltar, Hr.IIaBn P<
IB adiUnbivBiadaUulatntaddniM. _
"- ■- -It "•! ' li II iiTiiiaiil alBBtka 9
Ivi KsfliibadllloB.— .V. r "-" ■— -■ ■-- •— ■
ta:.^
EoiUtb
il-V.. L
kiiFMIarx'-Pby- ' tMatj—nOm
JPOSTER (MICHAEL). M.D., F.S.S..
P Ptc/ttnr nf FKjfsMogy in Oam^Hint f7nf«cni(fp. Bnelamit.
TEXT-BOOK OF PHYSIOLOGY. Second Aniei
MlIad.Kitb SalcniiTt Notri and Addlli
itralor of Eaparipieiilal Therapaulicp il
BIB. in one n.nnfome rojal ]2dio. volume uf about lOOC
Clulfa. %3 2h - ie.tbar, (3 -.b. {JmU It.ntd.-i
Il I. a [>l.a.l.| .111
nf»U>;>»afblr.gl.<
Vb^lt anptr p>a»B bx'iba'rbtt o(Tbaeaaia»- ] nm nadar*
Uaa~tlb*>nt Unmcaa adittai *)lblB alwali.. d.^Ulna^nli
BKialb. I. lU p»-Bl .bap., Iba work .III b. Jb^^i"!^,
loiitdibaraaxlilr«pW<bail>aa>,iM>Bi.di.r— ' P''?""'"(7«a»
IB Bh*>1»loiT baTlBc ba«B dilT Boileed bi
Anarr»a >i!t<,i-Miit. Ir«*r<l. SaT. td, IHI.
•d lilu»U<''ib*apporlUBiit i« re*lHi
nalorial added lulbotmof Ibtrornai
p*flBia*ial pbTduIofj tall loi.
CiBPERTIK'l PSIZI BSSAT O
I pbTtlali^nlbao Ibl
I ■adalBiplaUItt ■'-
[
Hknbt C. Lu's Son & Oo.'b Publioationh — ( Chemistry). 9
A TTFIELD [JOBS}. Fh.D..
CHKMISTRV, GENERAL. MEDICAL AND I'lURMACEUTICALi
TDelnclinglh>CbeBiUlrynftb>t;,8.PhirtD<u-oriaU. A Hungalor Ihea.oiTuI Frloelplx
aftheScUncr.ftndtbtlrAppUruIiov Id Medicine >iidPb«rmgicf . Eigbtb Edition, rtviitd
b;th«aiitb0r. In noe hrni'lnouie royitl l3aio, TQlamc otTO] pagai, wilb 87)llaitrBtiDn*.
Cloth, SIttO; If atbcr, 13 DO.
!*"!A
ft 4***lnpBnM at ■
a.iuii-i pc.av,!'— , naB >ii. llUM »»pllaaltaja ot ]
humlnttj lo vl>»Biur II !• »ui'e»ljr BHaxarr
9t ■• (o iar Ibat II uhlbllt ebanliirr la lu pn-
SBl idTiscad aUla.— OdttrisHKIt JMIobI Ifntt.
iprll. iBTd-
Th> papaUrllT *)>kli ihLi <rafk bo anJoTtd la
trloalolhaarliliml .nd i-lui ril.D<vi,l[l(ii sf|b«
'dauaii.ied
»blehrr>l(hti>mta
Iha daiBonxrillna of Iha Ulan daTalnpiaaa'li erl afals ilia pkanauapaU »id Itx "flalaal ptap
cbtaUarpilaelplai, (ad llia lila"! appJIsnltoBi of tlaaa: and ba liC'iallBoallr pullUf Iba natta
ardnoni lahgr oe Iba raTlaloa. aad tba ailait ofi vblcb aub lactlo* laproddad. Thna (ba tlsi
QEEENE {Wn.LTAM IT.). M.Ti..
A MANUAL OF MEDICAL CHEMISTRY.
Bimad npfln Bflwm.iB't M*4ia*l Chaniclry. In ana ro'
Kltb It lllaitrBtiont. Claih. II ^i. [Jutt Iuu*d.\
KortheTTsenrStiicIonts.
.1 12iDo. Tatnm* of 810 pagat.
nfglpiraul— PAda irtil.aiHlSMry, Fharmaev. Itt^iVO.
'llSt.IS».
ELEMENTARY QUANTITATIVE ANALYSIS. TiansUt^d with
notfi and addiliont by Eds^r ¥ Shitu, Pb.D . A»iatnn( Pror. «t Chemiair; in tha
Tnwna ScienliBa Scboiil. DniT. <if Pannn. In aoe bandsDma rojivl llino. Tolniae, of )I4
pigta, wilh 3fi llluiilCBtioni. Clotb, tl 00-
b.bir'h
la lb* a
I vf aStmlttry, Osi. I
"K
if ApT>lltA Ihtmlttrt in Ik> Hu/tal CoUtst of B^rtanfitr Irttimd.tla.
A MANUALOF QUALITATIVE ANALYSIS. FiomtlioSixlli Lon-
doo SdltloD. In one buidioma rDjBl 12mo. Toluma, with iliaitrBtiuD*. {Pttparins-t
fiEMSEN [IRA].. V.D.. Ph.D..
PRINCI PLES OP THEORETICAL CH KMISTRY, with 8|>e<-ial reference
la Iba ConaUtutlan of CbMolcal Oompnntida. Sew Edition, [o ana bBDdaoaia rujal
ISmo. TDiane o( Bbont tit ptgtt. (Fttparing.)
INTBOPrCTlON TO PRACTIC*
o'eocFTLiNSsopoRaAHii
[.SBMAHR'E I
OOir, Tram
L OF CBBHICAL PBTHIOl,-
SiNaY C. Lea's Son & Co.'a Publicatioets — (Ckemiatrjf\
pV)W,\'ES 'GEORGE), Ph.D.
A MANUAl, OF ELKMEN
l>rkeli«]. Reil>rd
Xil
of Ch.iiiiHrj,'
i^n Kdilfl t
R
«r
otipkr". "iih
IM
• Kur
H, laorMOk isd
'«■
v%
IMI> >r> IMM.*
ri'to'"'.''/."
•InplTABl
Hh.,«rt.„.-
ENTARY CHEMISTRY; Theoretical and
hjllelHT WlTTt, B A..F H.S.,sathDriir-'ADi«tieB-
' AmsrksD, trom lh> Tvsinb sod EnUrgtd Loodoa
mnoKa, H.D. In an* Ur^r roTt^l Itmo. valan*.
ini and > colotad plate. Clolli. tl 7S ; leatliBt, %S U-
/iium.nf pk..m., tat- ■^'^
1(M> '
illIlOX
. Tt»I>o'>t t.! oln
I IBU-l pl»c« » ■ ii«l.bi«.k, and ibt •!<
I
CHEMISTHY, INOUOANIC AND ORGANIC.
r Eitition. In i
IDIIIuilraUatia. (f f*- 1
riLOWKSi FRANK). fl-.SV,,
/■^«t../..«
AN ELEMENTARY TREATISE OK PRACTIC 4L CHEMISTIirl
AND Qt'ALlTAnVK ISORflAHIC ANALYSIS, Spocbrij adapl*!) for Ok In t
l.a)<arilori» of HohD«l> and Cnllcgtr and bj Bcginntro. StooBd AiB*ri«»s Troia ti
Third and RtvUad Bngli>>> Ediliurt. lo ona Tcr^ biiid>au* rojal ISoia. tdIdbb tfl
ST2 pngef, with 47 Ulaitratlom, Clotb. t1 iO. iJmi Uiutd.)
epW1»IlT'«"ni>'*'""l'*oi>»>''llnU<'lMliMiouln ' linuDia -ofajtri will md Ihi Ubl" »r- *•' /'''■kI
(bMj >■
I
.klii*>'>4'~l<l'il1at<>.b<lM>'l*»0 ' '
St."'
«d wIEti Iha naakpaialiun | 44 sal Ttnfinbrr to bnT4 qi*l vltb a ha«h ^fjl
TTOFFMANN [FRED.). A.M.. pOW'FR (FREH. B.). FhJ>..
■*-* Ph.D.and -* prnf ../ AftI Cliin UFMl.fJM.iffnii
A MANUAL OF CHEMICAL ANALYSIS. i
nfMBd
i>»] Cbtii
uiJ tbtii
T and QuulKj,
tl»n>. Far th* tif ■ uf PhiiTin«ii[«t>. Pbvt
iind PharnMaulUal «nd Madfcal Siudin
anlargad. la one lory bBodsonn nolBTc
fJEKMANN[L.l
EXPERIMENTAL PHARMACOLOGY.
for DtUrmiolniE lh« Phj'InlnylmJ Aoliona of Droit*, iran.i,
p*rini»ifln, nnd wILb oiOrialiroaddKlnTia, bj FoBinT Mikoa Phi'
nf PbjmliH in tha ltniv»t#t(y of PpatiiiTivii.ii.. In n-n hand
wilb 33 UiuliBlioiii. Clolb, 11 Ut. (Jait Snuif i
fnlly lllaftnted. {Ntarip KtaJp )
A Handbook of MMhortsI
h Iha
-. I>.«"
mhar
f
Hknrt C. Lsa's 80s & Co. '8 Publications — ( Phar., Mai. Mrd,, elc). 1 1
PARRISH (BDWARD).
A TREATISE ON PHARMACY. Deaigned as a TtsUBook for the
Sludent, »nd ai a QuIdB fur tbi Pb jslnitn aad PharmMaotlct. With mmf FaMniil* >d>I
PrcMriptioni. F«urlh Bditinn, tboraugbl; rcvisid, b; THOKi« S. VfiuHASD. In on*
hnndiomoOBUTO Tolom* of VSi pH«. with J80 lllnstrUioDi ; dloth, ti it ; laUbar, SB 6*1
batf RdisIb, tT
P^rhnp- use of tha mb.i liBrorUol, ir ocl ll.* iha publkirllli 111 th« iDiitnrixiporlaBrcof lit ■■-
■■uai >«|>iirli»l bxi-l DP" I pftrmtir irhlcb he Ibor, toil pacta up* anat Ibf irnn* fnn ilith olnt*
■PpHfad Id Ida EDflltb liati»(i Ima •n-sitt'il hlonil.— £anrf, Pkai-M .rifiiraaJ, Oct. IT, 1(171
fr.'iB lliatrapiailaBln pr*.^ -P.crl.li-. Pb.c- Ttas wnrlim«lH»Bllypf»,lUiil. add Im lbaf»M
S"f^ -J .r' r„.''T°J' » ."u". . .' .it. Vll iiiBcllofbalBsra»d«bl.imlliii«c«.iH..»bll.llfi^
•'ir 1 c bM.rmai «*^" l««l i« lii rliBfc i«c«"i-lrUil7«la«ilB«oli«PMr6r Th* wbala oorli
'»."u'D"M'''d\"loB*f"^al<'fu-'?.'.Uelo^ lunar— Jfad.Pr«»o»dC<rmi(or.iB«.lJ.' 87*.
QRIFFITH {R. EGLESFIELD). M.D.
A UNIVERSAL PORMFLARYiConUining the Methode of Prepar-
ing mnd AdmliiiiteriiigOIIein>t«.iidDtbBr H«<lla)tt«a. ThaoWiftdnpladtDPh^slBiBrt and
PbBfinBcciieMi. Tb<rdI!dlt<an.eanirDl1jr«Ti»dBii()naBfapnlnrEad,bj Jdiib M Maiici,
Pbar.D., PrnhaararMkl«rikMadiBalDlbe PbiladalpbU CoUtfaorPbBrmBcT. Tnondirp
BodhandiomaaotiiOTolum* otuboul BOO pagM. Clolh, $i M , lenLher. $i SO.
A mnra esnplal. [iirmDlnrrlban ItUla lli ptrK ' mltlad 10 mtinurT I17 ttatj iliidaDi of nrdlclBa.
aot rurm Ilia plmrinacl-i >ir pbT.iciliiii esald taardi) Aa n baiplo pbraloUB. It will bn touiti loialn.hla,
fbo'g'cop'iBiidiLiio'aB'l'HVlDH' Ka'c"orvhi>' | — nr J«rrfo<>f>rcaW(l(ait.r. Ja]r.lST4.
STTLLF lALFREP). *./>.. LLD.
Pr''f''>-"<r Th.^ntid Frarlii-uf il»IMvti,l\' Vnlrt^Ht^Hj Fmniyl^iila
THERAPEUTICS ANDMATERIA MEDICA ; a Systematic Treatise
on (be Aelion Bod Viet of M«dlciBBl Aeentu, including tbeir Daiflrlptiua Bnd Hlitnrjr
Fonrth Edition, raTiiedkndsnlBrgeil. Intwolargtisd hnndaDmrootHfOTOlDnetaf abODt
Snoepngaa. Cloth. ttO; laatbar, tlS; bBlf RofiiB, ralisd liindi. SIB.
III. 4ad naltrli madlea fur rar>r>B», li. t»a.1u rirm.tl'n farltai ph^'IcKp. Th* edUlus bufuca a.
llia*sb>BitlaBnrr»FnariHl<lliiBii.lbiHalbar)iBaUld 1 «/ P«<in>aay. Fab ICTK.
Iha priifanUD gndrr raBawH nhllgatlnt*, hr Itaa w* sbb baldly BrtnKlhBl II baa a rtTBl !■ tlii
laaatiifa vark'nBiaiiaatlyaaFlilamanKl >>» bbj .,"J„j'S,Jfl°j||,J„, hi,"ar1.a, BBd w. wn'.'i m-Im *i
T'hVmUh»Vl«"I!™i*ThSsitwV%'»«iV.^^^^^ ' * "'"• '" "" "'■'■'•'•■■• "'""» ■ ""•■ '"'''••'■ »•
w.TirB«-j.tii"td«o^i"t."°n'bi;flw^^
pARQVnARS!ON [UnnERT]. M.n..
A GUIDE TO THERAPEUTICS AND MATERIA MEDIOA. Third
Ameriann Bdition. ■preliiMrrinlMd by tbe Antbor. Bnlaritad avdadnptrd tothr T. R.
PharmaBapipiii. B* FaiHK Woodbitiit. H.D. In odb van hundietn* lima. Tnlnm* ot
bU pagsa. Clnlb. (I !B- (J"-* R«rf« )
FnoH TKH FniTon'a pRirinx to thi Taiitn Bnmon.
The prriBnt TOlnma ia an intalliEant aflnrt to prcacnt. In mndarnts ODinparii, rui<b wall-dijcaatnt
raeli ennfarninjt tba plijaialaglial and tbaraprniinal nolion nf fmadiei B> ars ranannnbly piinb-
Itabad np 1" IW preianl lima. Bjr a eonnnianl airJin^araant tba BftrranpfindlBir BlTatrla nt aanh
Brliole in hanllh and dItaB» •» praaantod in pnrallal rolamnf, nat only roidarintr rrraranEo
aaaler. haL nlan lnpra»[n( iha flifipa tnora alroncly upon ths mind ot tha raidar. Tb« imtbor
pranrlptiana. in dafcrBnea M tha ilamanda of Mianliaa nrnfraaa nnd onirormllT of ob»ar»ation.
A ready rafafaoeo IbMb of Poiiona hna bam planad at Ibe and of tha bnok, and in tha lait IWalf
tha t«ti of the prominent poiaonn hn» baan Inaarlail It in bopad Ihnt tba very aararul reviilDn
■nd itddltiona that ban bean made <n tha wr>rl( Cwhioii bars insrenaad iU 5i>e nanrly ono-third)
hara nriinnrilnnallT Incraaaed Ita yaloe to Iba atHdanl
■ -' "— ' - ■—-■ - ■'■'-' --"■' • ■"- it.tV .b"Bld b
iVnb'wbo u>a'*Bl{7»^aihe h"".* TNaanhlV-
b»aBllf>i11y tt— ■•- — -
y praelleal ahBfaatar liia«b»T wit
'•••of anpramloB la both ilia plly<!oi
a Ittt (kal II l> rally Bbraol irl
IS IlEKsr C. Lka'b Som A Od.'b Pubuoatioeis — (Mat.Med.aHd Therap.). ^
tJTlLLi [ALFRED). M.n..LL.P..and \fAlSCH (JOHN M.). Pkar.t/..
O praf af T\t'\ra and Pratileiu/ Ifdlelf ■i**- t^:/. a/Mat MtU. anil Bat Im PkiJo.
and of Clliual Xtd. in nniv.uf Pa. n«ll.Fhirmii<y,iltt» tflhi Amm-Man
THE NATIONAL DISPENSATOHT : CoiilaininE the Nnlara] History.
Cfasmiitrj. Pbtrmaej, Aetionr Bud Ven nf HwlicinH. iosluding (hoH tfooniittd ia
tb* PharmAcoptriar of lh> Unllad Btntea, llrest Britain and aitniunj, with soair-
DDf tshraocm lo the Pranoli Codci, Stcood B'litiuD. thorauehly caTiMd, iiilh namvraBi
■dditloni. In nnt icr; handnomr nsinfn FolDm* of 1893 paCH.wilb S3B llJiiflrMic--
Rilra aloth, (0 75 ; Itatbar, raiiad banda, IT 60 f hnit Biuwlii, ralaed band* mi o;
bark, <S 39. (ATgw Aui/y)
In the reoent rni noun cement of the United Statkb PnABUACocaiA of 1880, ft 1&>t '
IB given nf ne<F iiiaieriul Inserted, sdiI of the 102 items aniler the head of Kkw IXivoa,^ |
Oils AMD ExTBAcra. all are in the Nationai. Disprnsatory exceptJng 6, wtile of tbs
Fi.viD Extracts quite a large proportion is included. Bedsides embracing practically
the whole Umtkd States Pharxacopieia the Natiokal Dispinsatobt contain* n long
li«t t>r unoDBcinal drags And preparations, and aUo selections Trom the recpTit Oernian
and Frenuli PhurniHcopceias. Purchasers will therefore find thai the Nationai. Dm-
fKKSATORV. set-'oiid edition, ii, for all praciicul purposes, a vomnieiitarj oo the Ukitkd
StaTKS pHARllACOpmU of 1B80.
I
FnoH the PaaPAca to ths Sicu.vd Cditk
Tba opportiinli; Tar a rsviiion haa«aahl<d tb- auibara to icrulini
to Inlroduoe ■lUnlinnii nnd nddltioni wberci«r thf ra bas iHiDcd
rnant nr greater Dompletana?*. Tba prinoipal cbnngai lo be DOttd n
ral drugi under eeparDts headiagi, and of a Ikrg* Dumber of dro
Daulisitl preporationi claitified a£ allied drag! aad prapatalioni c
JopiBIB
■rllBlee fram tt
h Codex
t vork aa a whol*. 114
lintrDdDCCiuDDrtava-
nnder the beading of moT*
art nearlj tba eatira aermaa
Ml HBH i0V>atigStiBD> -hi«h
oeiTed doe eoaFiileraliDO.
Tha««rl«ofill
ilmtio
beennddail.aDdillllmo
Wbil* numerou
addili
aodinoriDedioinM and
maka them a. «<.
ociu-
doiM have b>«D e
P"""
purpooa of maJfo
tboee
way tar i(a inlTod
Tbr Therapeutl
allnd
Bumberlnllopre
lent ed
lemed ■■» satjarnstorj.
to the laotioni irbiob relute to lb* phjRlologltt
atment of diicue, great care bai b**n takaa la
at rendering thvm iDCooiplete or obieora, Tbt
Df trojrweigbt nnd of lb* metiieai fjatem, forth*
lenaatorr raroillftr with the lstt*r, and pariog tb*
t b7 nbuDt IliO new refareDces, Baking Iba taUl
of talcleBl LiBporuDeii iturlaf Ibe Ume of (Uool-
■■barallag, ead ihaikorllatirTal ilipHdalnea it*
pr*TtoB>piiblle*lluB, Altar bating <oae enrerBlljr
eOqaeotloB vim Pkarnimer, Hsttria ktiXct, mni
TaerapeBilBi.— Jia. ^BWr-o/J-AanMr^. Km mi.
irark bj Iba prahuloB. Tb* rJipliT lale gl tli* Ir*!
edllloB Diail butt ladawd bnlb Ibe edluri Had Ibe
pBhlUli'i t„ Ban. unpitalloH fur . b*w adUlva
l^aaadlBlalr atcar Iba Inl bad bta lunad, hr ■■
1 of lb* pidlOB* IMI aiterad «Bd Idii««t*iI,
■nan.t'nnioriia'-' I -i Tb*™
f*4Cinrial>iirlnu('><iiit.b>ii't1..'.h>.i<' Kuwdi^to. /
iroladat a dliim.aiuTT nblcJi U D"t milT nmMnul, I
Bui vUl Be a lairtliiir neaBilal uf Ibelr leBralBg.— ~ 1
miiwtirr'' Mi^ttai juuikU, not. ic7«. - 1
lilabjfkr taanlBlaraaHsBil or ail«*i«al Oua
nr oiliir buab it (ba kla4 la «ar lannan. aad
S'Te e^npr*beB>ti* (■ ereir tawt.—faclft Mti.
■>il Strg. Jbh-*.. on. iSlf.
)■ ticTeBl dUpoM lb*
.rnn«b»ai wBtlaU U
Henry C. Lba'b Sob k Co.'b PobLioatioms — (Mat. Med. S nislology). IS
JifAlSCH (JOHN M.), Phar. li..
A MANUAL OF OKflAN^EC MATERIA MKDICA. Bnn? n Onirfo
In MttUrU Hf ctlon nf tbs Vi>«Btnbl> nod Animal Rln^ilanit. For lb* Uec of etnJtnli.
Dragglttt, PhnrmncMt imil Phj'iaiini. In one handaoma ro^iil nmn. vnlnnit at til
pngH, with lO-l bttLBlimi Illn'IrUloiii on wond. CloLh, tl T9. <.r>i« Ki-'dyA
*t„f\jl.
Dfph.r
>lK<l«»llw<>nlil b<dlfl»Ul<>aad Is II ■ •upir- ' an nxoj daimit Tdo «<.rvdlll(i* Ih* t.oi'k rslllo.
''"desla^SuXm Jfiid. a<t<l
to b«. ua <• I I
OB. — CUcaye ^
nOA TS iJOi^KPn). M.D.. F. F.P.S..
^ FalhUogirt (0 1*1 aiaignw ITut'n 7BJ»n»"r*
A TKEATISE ON PATHOLOaY'.
flORXII. [ I',).
DASViEU (L.).
very liduilsome octavo
■■ (/«p™.-
AND
A \f ANUALOB' PATHOLOOtCAL mSTOLOOT. Tran8late<l.wilb
NoMi tni Additinof, bjr K. 0. bBAiiBPtAM. M. t> .PniholDjcM and OphlhtlmleSutganii
lo PbilrtJ*. lUtpiinl, LectdTir on K*rrroti..n and Oiwrsliva OpMbnlaic BviTgriv In VaU.
orPcnun.in'l by J. Qisnr C 8tMifl, M D.. OfaoBalratir cf Pithologlcal Hlrt»lo|-T in
the Ubit. of Pb. In dbb vorj h>B<lrnm<- o«t»t(. vnlame of 800 pnp»«, with 3«(l iliut.
iHtlDM. Claib. (E SOi iitlhBr. fabO; hslf Raiila. |T. (JVw Rtadf.)
Bwrj nlvilol uf p»tbgiO(j— and "taij pr«il-
tootr OBiM M bo « •mdlBI of ptlholD(T'.l.ial4
of pttbBlo
TbI-i \m%
• »••- ; ta riBt. a (r>al d*al r>t wrlUnadimiii.l
■11*1 1> onlltelad IDadhfTbar* wbltli 1b nni taallv
irriBi<*d 1
„,.* IB tb< »» bra aarfhrhi •W-Cun. JTxf
>) Snrf Jnimai, Jaa*. IIW,
>b>>>ibl<irl
Tb.W bool. I> not • MlUgUM of tba work* or
.ltibl»l b
»oUdf*aBdlBf*>(1>a1li>D upaa ••»! )>'(•■ a°a-
.l..d by aad cOB<ri.lll»f Ibr •rock d( otb.ri. la
haait'otA
tri. !•• If*>«>1atl.>ii ha. n.d. tl Iho h»l wa.k l»
kfvi} U. IS
'liOln«r.u.taabl*liioorl»Bgaag*. fto.thanTBrT
pdcul »>t.lDlT "B«lil l" lia...-af rtlw <./ M.4.
■(».. A»rll. ISBO
<.gal Hl.lologr" •• lb. b"' work «t ibt klad
phr*i*l*B>
anr laltBaia, a>d .. i.lTla( to tu r..d.t. .
>li>rvf Iha .pv'"l«ll''«'''l'"P'"il«»lbai'iii«-
*«Ii.J't /■
WIlboBt lb*
la.*r>< h«a»l
I. Mtd. rimim.
(JVBAPEB [EOWAFD ALBERT). M.D.,
A COrilSE OF PRACTICAL HISTOLOGY: BsiriR an IntrodattioD to
tba Ubb o( ths MitroaaopB. In i)n> handtDiee royal llmo. loluna Of SBB pbgai, with
- '■■ - "■ ■^. $2 00.
n.llh)F.N (T. HENRY). M.D..
'-' l.ttitUTiroK Fa/Solnffv and VnrMd inn
•tBotpl'alXMratSehoal.Me.
PATHOLOGY AND MORBID ANATOMY. Fifth Amprican.n-otn
Ibr Siitb Rnlargfd anit Reviaad Engliab Edition, Inonr 'trj bandians MtaTaiolama
of aboul SSn pagnai nitb abnut \iO Una eagra<iiig>. iPrrimrtHg.)
A f*« notioM of lbs [iTiTiuDB rdltioB sra Bpptndrd.
■tifaltaa
IWh*(g
pirtniiaii 111 msdielnahu lO aaeb prnfmia bara irxt hliiblf i<i all ainnanlaiDil lo IbnH praeiliii<B*[i
iBad<«(lal*a>lBih*l»rpatk->l<ut7.iapporirdaalt who bits buI a ncusi kIIiiub, and wbu aaii lu
I'g^l abaml'lijr. aad lb*Ml>aal lh>ba>lt ul aal wk'lak hll oBdar <halr daUf obnarTalloa.—aiii
■■* '- -'tlrapaji nu«l>rMtltl«aati /ourH. o/ Jfail flrtmoa
14 HsMsr G. Lka's Soic &, Co. 'a Fcblidatiohs — (Fraatica,
DRfSTO WF.{JOBN STBIt). M D . FRCP..
A TREATISE ON THK I'ltACTICE OF MKDlCINE,
k-iD KdUion, riiiaad by tba Auihor. Editad. oilb AdditloriF. b; Jam>
>.M-l>.,rh]ritciiiD (otb> Ptni
■ I Lh' L-atsfil lubori of t]i( kfliliDr
' aititBurgltat/tnmal, Fahrnur]'.
Second
n llu'
>i OB; Itsthar, tt 00^ bslf BumU,
(•nmobo-kliihlrritiiiDr .IKbuUH
».'ii7» o. U> -uk >cl. a.>u1d.t<Nl."— 0«(
a>e>ril.r.J>a.T.lt«<i.
Tb> R><l't will tad •rirr foiwlribla
ennaiKUit Willi llm finudea af iii*tlclB* •!
•(■■•il. la ■•Irlaat immtHr, lalrivitiu •
elts. Tha adJllMa* arfa <■/ Dr. Hnidblar
ii*anilHM la AnarlatD railTa.— A^pda Jtarf. «■<
aurg. Joun, Marab. I«W,
Varantdtl aoDi-iiaalli-
fttr pmoaimara ll It (U.f 1)- itrtli.a, Ibi aiiUurt
XTl* l> ■llHcllTa, tad ll !■ -[■•"■"r '" *•• "*■
fn*d eliainl pMD^.*(iVuNI»a.*"-^t tat(. «7».
fi.ctrd. Vab.
pUNWICK I.^AMUEL). M.D.,
TRR STUDENT'S GUIDE TO
Third Karl»d nnil Kniarged KoglU
Toluma of m F^gea. wilb HT illaiir*
poTHERaJLL iJ. MIhSER).M.[). KM,,.. M.R r.P. /,-i
-* ^fir. Phya-la'A* IPur tnwl Jl">Ji ; .I(It. /■Ay*. <m
THE STUDENT'S GUIDE TO MEDICAL P1A(1N08IS. From Ihe
Third Karl»d noil Kniarged Kngllfb Edition. In 0D« Tary ta&nd*Olii« (Ojal \t»o,
ToIuma of m F^gea. wilb HT i1la>ir»UoB«oo wood, Oloth. It S5.
THBPRACTITIONEK'S HAIJDBOOK OP TREATMENT; Or. Tli«
Prinolplaa of TharKpaotir!*. E>odihI BdUioo. rariacd and anLaPgad Id on, *ert Iiand
"U pftga*. Cloth, tiWi var; bnndtoma half Ruitic,
d banda, |6 61. t^ud /inwrf.
aatlr and tauraallaclT
■a in ad ar vra>albla(
Mlad ptfalaiaa tat feliaVnrti Inward ratloialtHag
of phj^lolMT. B-a'» obapur. alarj Use, haa Iha
lBpr*»- or ■ a*>t>r hitBd. aad wliILt iha woik la
IhoroBililJMltallflaln-'ary uiFilctilar, llpraianU
iBlka lliaagtiL'al CHdarall iha cbarnn a.il ba.a-
waUitopdlab>wllli»a
urlilnatllj naka. II *l
ifnd Burt., Otl, 19*0,
l.vfnll JirntH. lo t work o( lb
irwlll bKlinpo-alhlala a rg
•C'pi aad (bar.
Iljapprwutad
fJABKHSHON (S- 0.1 M-D.
M-i 8nWr Ph^fJan In undtoCa baluriroaM* /VAie'ii'ififirf /VwHata/ JMtMwnt 9op'f
ON THE DISEASES OF THE ABDOMEN, COMPRISING THOSR
it tha StniDX^h. and other parti of tfae Alimanlar; Cnnal. (Eaophngii), Cvtiin. Tnlaa
inBaBo. Sarimd Atn.rk>n.fr<'m thaTbltdBnUrg
.i =Bd Ravi..
With illo«tr«li«(.». iB ..na baBdtoma .wU.u valDn
a of iH paga
Cloth, tl 10. I/^r'« 7.««i-)
loBiHm A faW piiinniUoa o'aMli chaiitarladaioifi
!■> ifaiiianii-, palkoluKf aad tb'rapanilea. Tba
u bear s jtTL A« 0 P p atholoq ioa l Histuuxii.
laa.abjaal HI broad •■«
mad •iiidr (ai kMaalf—
. BllolafUalaad Tbara-
nflsrtg, with no c»ppar-pUla l(nrat. pUla a
*»lo«d. Ctatb, (irn
BOLtAND'S XBDICAL SOTKK AUD BBrtI
TIUXS I rut «•» . t>p Sim. Cli'lb, «3M.
HiKLoWB NAIirAL np THK fHACTICK (
IIBDlCinil. Wilb AJdliloai hf », P. r II an
LA HOCBS OH PRKDHOIIlA
- au<> Ciolk.Hm.
P*Vf» TRBATISB Olt TUB FDItCTIOIt O
lilfHB laoaa baad'
. CIvtb, tlW.
HuiftT C. Lia's Son & Oo.'b Publioations — (Practicfof Xedtcine). 15
PLINT (A USTIN). M.D.,
A TREATISE ON THE PRINCIPLES -AND PRACTICE OF
VBDICINB ; d»<fED«d for tha nat at Stadenti Bud PrMt>(ioae» of Midicin*. Vitlb
Silitlan, (Dtirelj rcwrUUn nod nanb improi'td- Ibodb Urf{s und close Ij prlplad ogtuTo
Tnliimr nf ll&O pugtu. Cloth, $i &0; lotbar, t* »; Tcr; htniliomcbAlf RouU, ralawl
bimdi. tT. (jHil/innf.)
Tkl>w.>rkba>bgaB>nloiis>adntTor.t>l7kii«n.| jain h>rg'> It M»I4< ih> ptnn Is •ni.m.—Kaih-
knd ku nbulnxl *□ hilh ■ (KwltlE-n ■.ngB^M nvd- 1 «lll* Jnurn a/ Kid. itnd Sure . ''>•■ 1^1-
UD KMIIui ID DiBdUlsf, IhM ll lo Hirdlf BMu- «f ||bi', pngiiu" u ra«i<gl»d IK bo B.lllKtlM
..t/intfo inof.lli.B BBiioiiD** tha puMliB'loi gf i,„ii„ „( high riBk apaa Ihe prlai-lnl.. Bud lU
Ibl- Oftli .diLl-a. ill who pflrw II bib-I b. -Irnrt pf„ilo. nl Di.dlrtlns wb.r.rni lb. EBgll.h l.«SB>k||i
k* Id* ■■IHidn naaaril) vblab bai ><*•« aad>^ | ,, ^.^ Tha ojilolno* ••CTirbiT* r>(«-l <>i*n>B
jinii.ov'BiMspB"'!"-; !■ ■'- ' ■■" "■;' ir..°s-*<jpj,'rIi>"iJ,'ia8i.'"" "'" "*
«fBll.riod»ldM«Mii>luliDr«wiIh r.-.'"iilp.ilh»- ■"•■flaal ■ehoel*. Bad Iha k1«h poaHlna Bnai-tlBi l»
lOfliiBt laqaliy IkSB Bur M«llu worli irlih which ji_[J JJJK'Jiit ' '■ti*'b''k*m. "b.Tilll i"f- tar.ji
iTTaalfc^?" ha psHau>d or ih*."." oltl»'' 'h« P""lil •'•■«'" Iha »,"!•»""; "•I"""* — _ii»"
elm i-iir-»ill0B. Ibouhiral dl«iimln.I|.'B, mj oa*""""! and (
lanai jtillfnm —lonitn tan«(, JbI^ M, IB81. ' yl^J^^'jif'X
le.— J(ur»fiii>d Vx'fnl
LB MittVa'aw "llhlil Iba pail fl" JMi-i. Ha H 'ha mm nit»Jlo
B biaa adJail. , do w, »■ ha l> «tlTBlr aflfaiad la hla prufaa.laa,
lu Inni hun wklak'anrr AiaarlaaB phfaMBB atianl-1 ka-a Bpos
will b* luar I J.,5"„^ g ""■f^'^al. uTtfh, 1«"'
DT THB atMS AUTUOS.
CLINIOAI, MKniCINR; a Svstcmntlc Tretiliso on the Pingtiosis
Bnd Trentrarnt of Dineuai. Deilgnad fnr SluJeolF And PrutUloaart of Ma.tUiIna. In
nne Inrga and bBnd<r>me nrtiiTo tolumt of THR pBgee. Clulb. M M ; Isathar. %i BO ;
buir RumU. tS- (LuH/y lnutd.)
UauBDlrx k> ihBl of Iha aolhor af tiro wmkt
lal, Dai. IMt
*• mnld dailra.— SI. ItHU (TIf ■>. Xieard.Ogt. I»7I.
It la ban thai iba akill aid laBtalBfof Ikacrnt
hoaia '.r raadlcal kaowlalia. aicallaol for lh> •lo-
l.ag'llft orih(''Bii>BI th'rilfal cllakal iroili, eoll.tl-
ad S:r»B cBsrij a. Tl|rtl»Bt lad .j-'limallt a> Ba-
■ •ria« Bad oatgkM hj a iB^gmMl a« l«. al.ar
IhBo h.a nH-r..li<.B la aloaa.- JreA<B.« ./ M^ll-
Hn: l>M. \nt
of BB "rdlaarr diaenllT; bal lo Bteinipll^h ihl.
stdBl<".aUl'iniri>rihan.la'illliBi>r<di*oa'li. TBlx
aar>tkaopar'l>li»ic«-uh^I't rilst. vhote aaiB«
UalraidrraBiltlarloiiadnBiinfBdnBcedniadltlaf
DT THE SAMS AUTBOIt. "
KSSAVS ON GOXSERrATIVR MRDrCTNE AND KIXDRED
Tones. In ODB rarj bandioma rojai 13ma. valutaa. Cloth. $t 36.
THROES' INTRODHCTIOB TO THR STDDY Ot
CI.INlCAI.XBCi[CINB. BalagallBldiliaihalB-
'olBB*. QIalb.tlU
Dr.
fn
t hat Iha honllj
of anpraMlBK hIB
If
(Bd Bl lb* aaaa 1
ma aaeenel.sl]'
aHb..ad.l thaaan
allBi ohUlB .11
(IhroBfh.n iBia
tt»b
m,-jr. tVb*, /«
Br..l!o».m*
,,f..i«W..ii.t»pi«.
hafata tha raad*
Bla
IS
TtX
"'
111* tunplftalB
gBrlr-naad, Ibal ha o
t. .PMI.1 d*.<(B,
B bj II. aid, k,r
rit
II
. wIlhoBI aagl..
oar Iha' aneh a imflt li m»>l*Bla>hl
ntpaloUladlaitBO-l'B
err
la
BtaBrrlalla.alBa
fa* mlaflUa rafnak
dam
hi. l'>il.Bi .Kaatlo
—miuHmnat* La
i Variocs m-j
iM|ilUI, ChlcBfo. UIKd \J ral
PtTia. U.D. B«"«d •*"""'■ •''"!•''„ i; "■•to no's OttHrCAL LBCTCnsa ON CtKTjIlM
hBadMnaiirrallliBa. TolSBii. Clolh. •! M. ACItTB UIBKiSBS, la aaa ihIbtb rulaaa, of fH
CHiKBBRS- M*ND*t. or D1IT A!in RB(IIHB!ll pjifsi. Cloiha^'iMI
iS HB4I.TH 4.H0 SlCK^Bsa. lac ' ■ "'
a«toT«BatB»a. Cloth.MH.
16 IlMnT C. L«A'B Son &. Ca'B PvatJaxtiOH»-~{PraeUeeo/ Makciiu).
fffCHARDSOy (BESJ. W.). M.A.. M.D., LL.D., P.R^„ F.S.A„
-**• fW~>B«flli, a«taii!atUgtQf Pkvitian; hodden.
PRHVKNTIVE MEDICINE. ]noneoetaroTolaineor»bogt 5CI0pMges. I
(P«p.r.,.,0 ^ _^_^
flAnTfilTORNE {RBSRT), M.D.,
ESSRNTIALS OF THE PRISC1PLK8 AND PRACTICE OF MBDI-
riKR. A hnndj booh for Sladtnla and Prixrlitioner* Plftb Kdiitnn, lbDn>0|;bl7 n-
>»c'l tad rxitiUcn. Id «■ bindtoiii* ro^it 1!mn. rnlume, olAGV page*, vith Ml l»u-
mtloni Crotb. 1S.T&; hair baand, |» 00. fJuii Rfadt )
Th> Tarf groal lurcB'n nhiih Km >ib>a«t«l tout large edllions af tfaii work abon (bal tk*
•Htbor bi> (DacHilid in tup ply in k ■ iriDt Mt bj a JiirKi pflrlinn oftha prghnicn. It bajala*
•tikbUd hlB ia lUMKHtt rETuiont to prrttn ib« daUWi nf bU plan, and to rindtr Ibc *ark
f till Bore wnrlbj of lh> fnTur irith wblob Ir baa bt«a isetitad. Id Ui« prrMOt tdition H**Ml
bnniired brid ■ddili'>D( ban bsm nrndr, a nuinbfr or na* (akiMta bara bean wriUatt npoB,
•apaoiallj in sonna«iion with the Palfanlngj n{ Iha Karroiia Sjitam, Iha illBf trail ont haaa bMB
MMidarablr iaer*l**i|, and a large uuuiIki oC atn and earefuJly Hieeted roronlB for the adal-
BlatHtloB oriaadleliH(ha>*beaDintraddoed. An Ma on nt 1> giTea. alio, ia IbU edUioB hr Iba
■ri( llaa, af lb* nethud erprtaaHblDK aeBiirdiagto tba EDatrio»l •7>tein. ajtd ■ •aalloa ia ad^ad
apoa E;eilgbt, lt> Eiaminatlon and Oorreelion. In preMfillng Ibi* adilim, Ihanftira, lb* pub-
Aaberaraal (bat it la in atery najirurthjiaoiiBlIiiaaniieDrtbe farsr biibartoMcardad tbi* vork.
Tba iDlbnc of Ihia b»Ak ■via to b>»a1»r*d no | •(ii<l>iil> ud vrulllJuaari. Bo ihurewblT baa ba
liaLea lu lir>B( It aproitie Di<dara lUiidptfl*!. farai ' 41<HtM bla mauilal'. aad ■»_ all rati Inly baa^ka
the fnttfUa. Carlalal]
pain. Tb>
ad It to Ibe lkT«-
■alia Iba aid «r lu
<ra balpral Is lu
radldawwarillr
a, Tat (iBpU a*d
!»ee"a Cmar tdVuuaftad Ibal^'rHar'^'d'- I a'tkaTe^ta'al '//''aMba a'b]act!*^ll i. c>MUr
"ir.^t
ilbtawurk bead la a pmpai ^•if.a<id«urr./«»<x>',J
,11 ba Df «raa
txroonBrFF (frank). m.d..
'' PSv'rini- '" l>.r Grrma-H H<^f,llal, Fh.laMtikia: lalt Ohitf AirlrtanI la II,' Umtiral OltnU
A HANDBOOK OF TITE PRINCIPLES AND PRACTICE OF
Madioine ] for tb> aaa of 8tad«ala ud Practitlonera. lu one royal llnv. Toluua, wBk
Ulualrationi. {Pnjia
JptSLATf^ON {JAMES). V.D..
-» FhK'Idan «>ri £wf uiw ua Qlininl 1
il JbdlT(iia<a lb- arairav Wtrttr* rMraaary, aK.
CMNICAL DIAGNOSIS; A Handbook for Siuflents and Pr»o-
• of MadiolD*. In one haDdinraa liioo. volam*. of MA paget, with »t tllnttrb-
I .galiK n.a l'tl<ir>. ,iaac<.i>daiiiadruriiiaUlliall<
>I4 and •leb-rcK.ra. 1 aid dla|ou<ile> l> be foaad I
«!a la'aay
UTAT80N [THOMAS). UD.
LECTURES ON THE PRINCIPLES AND PRaCTICB OF
PUTSIC Doli»«r.d at King'* Coll.ga. Undon A Na- Amarlcan, from Iba FtM
KnglUb Ediliim, reviled and onlrvrgad. Bdlled, with ;>ilditlona, and 190 tlloiUaiio&i.bT
HK.nr HAnT«iio>j.i, AM.. M.D., tale ProfeMor of Bygifna in th.. nnirer.lijof ?,«.
•yl.ania. In two large and bunJaoma omairo vulomat. Cloth. |B 00 Meathor. «11 «.
RrcoNsi:Mi>Tioi<:iia| viLBHEuarnsDiKKiteKsoFTBRitBLRTAirc
laoii •raatDaat, WuhHoiua. KkEAT VBSSgf.S, TLIril Amrricaa Bullloa. la
loaaaod Ca.a. lo aiamplirr lie 1 t.1. Bra., iio pp. utnm. «t on.
laa oalaao Tvluua al tbuoi »» 3.VITB OK COBSPKPTtOII ; ITU BASH *XI> Xk-
UKDIASLEHTiORG I aol S*n , fp .»«. %%M.
wTir'.'.'M/'B""' '"'■'■*■ *'■■' nisBASSKOF TUB I, Unas ahb aIR-
BaeoadaadHaflaadi s-—-,-—^ _ *^ -r.,„«M««.. »*.,-. •k- i — .
>. lolome. Clotb. h',°C EV.lith™ '
Hbnrt C. Lba'b Sos it Co.'B pDBllCATioi»8 — (Practice of Medicine). IT
TfETt^'OLDS (J. RUSSELL). M-P..
■**■ ft-™/. V*" PHtMrtj)lMan'l Fi-ietia •>/ Mm
lt.«t,
MtHI't^tti Univ. Oo'Uft. Londoo.
A SYBTKM OF MRnH'ING witr Notbb ahd Additions ft II^nkt n»iiM.
HORNK, A.U,.M.D .Ut< ProfFPBororHjgianfinthoUDlTerMljof rrnnn. iDthiertBrga
and hnnilnonir octaro ioIbibm, i^DDiaiiiiiig -lOAS cloiialj prinlad dDafale-palDninvl f»lf*,
vilh .nrillastrallna*. Prio pet vol,, ololh. (i.OO ; ib«p. |R.aG: Tery hnndfom* h»l(
BdsiU, niRid biindt, IB.SO. Per Hi, olotti, SIS; (beep, <IS; half Bumis. tllM.
{SoUmttaig mhtiipiioH.)
rOLDHCl. IHSCrfufvlaOntalDsGEREIULlllBIAlKlklldDlimEBBOI'TBKirKHVQriSTSTCH
roLUMB TI, {now r»ir^y) oaDtalns DisaisMS or JUapibatokt aaJ Cibcvi.>turt Sthtshi.
rgLtiMi ITI. (notr rfady) «onUln« Sibeisks or tat DiBtiriTB and Blood-QuHdVLAB
SrsTiHs. or rni Urinart ORSAira, or tb* Fimi-a KipitaDucTirc Skirh, and or tbb
CrT*ICI<l1Is8rBTEH.
Rejineldi' Stbcrh or Hkdicmb, rMentl; suwplclcd. hu Bcqalr*d. tiner tbe flrM npJIBiiTRnte
<r tbe Hral mlume, Ibc well drirrred repulalinn nf being the work in wbiifa rnntlern BHIbh
De<lloiD*iiipr«i*ntBillsltKrnl]«lind tDCMtprnetiBilforra. Thla sonld esirre be ollieMri** in
lew nf ibBfurt tbneil i* Ibe reoull af tb* eollaboTMian of lb* landing minds of tbe prnrMflon,
Bcb lubleei b>ini trentfd b;* mmt )tantlem*n wbn li regRnied M ill bighett nutborit* — lu foi
tbe Bladder b; »\r HuoRr TRgKTBOK. HslpotillDna at tbe Uleiua bj
niLr HrwiiT, iniBoi'j bj IIkubt Macmlrit. Oonannption bj J. Hifoiiei Bbhubt, liia-
ie» of Ibe Spine b;CBAiii.ia Bi.ian Ritncbirri, PerloinlUia by Fbakcii Sibsob. Alei.hnlij-oi
Frarcib E. Asbtib, fiioil Aflmtioua by WittiAH RoRSBTa, AKlbmn hj Htdb HAr.riB,
rebrni Affeetinni bj H Dharltoh BiBTiAN. Snut and KbanmBtlam bj ALVtiin Bahivb Qi,t.-
n, O.mititulinnal STphiKa hT JoKATRAK Rdtchirmv. Direuaea of the Btomiiah by WiLSOi
X. DIaeiiaei of Ibe Skin b; BAi.tIAXi") SODIBB, ASectiona of (be Laryni bj ManiLL Mac-
RIIR, DiMUta of [be Beetnm by Bli^iAbd CdbiikO. UiBbalFi by LAoncB BBuimiia. Inlei-
nl LilaeBjief by JdBK 8tbr Briitukb, Culilrpi'y and Romnamballjiin b,TTROM«« Ki!in Cn««-
BB. Apoplexy by J. IlDdaLtReB JACnaoK. Anglnn Peelsrie by Prnftisor QAtRSHBn, Bmptij-
CB of tha Lunga by Pir William Jkkhbr, eta ete. All the leMdingaebaelB in Qcent BrlUls
vc ounltihuted tbelr beat men in gsaaroos rivalry, to bojld ap Ibla miinaaant oruiadiekl te\-
te. St. BBribnlomeir'a. flny'a. Si. Thomna'. OnrfffaHy Coll-ge. St. Miify'a, hi I.ondnn, whlla
! Edlnburgb. Qlaagow and Kiinoheateraohoola areanaally well repcenn ted, the Army MeJIcBl
bo..l at Nelley. tb* militBry and naval fervicea, and th* pnbllo bnlth boardl. That a work
!lf andeXparimre, auitcd inlha dallf wantaattbapmet.liliinar, «*■ Inentiabla, and
red in Bogland, and Ibe repatatlon whieh it haa afqair^d in tllSa
IQB Aiianno. DaTeaeaieditwUbtbeapprnbatinn of Ibe twn pre-eminently prBeTir^ul naltona,
nrge lite and high price bnving kapt it beyond Ibe rencb of many praollllopera In tbla
y whn daalre to poiieta it, a demand baa nrltan fbr nn edition at ■ prira whifh vhall rf
tr*B«iiry nf fa
■(«hl«b ll
der i
.all. To I
9 tolnneaondllTalbDUMTii
umnx, been oompreoed in
oely prInUd. and offered a
iean ptofaailon.
It Ibia
pBEeaoftheorlgina
mailer type iinddou
The
But not only U Iha Ameriaan aditlon more conrenient nnd Invar rrlead than tb* BDillab;
it fi alto batlar and mere Ciimpleia. Borne yenra baelDP eUpied tinne tbe appearane* nf a
porlioD ol tb* «<>rk, additlont are reqaired tn bring np toe psbjeeti to tha eiisting eondttion
e anlolaa dsTOled to then ta the Wanta of Iha American '
whieb Che reoeired practlea In tbia eoanlry dilTera fmu
M deflliODniea haa been undarUken by Ubh ~ "
BOBBE, U D..I«t*PrareMorerHygienaln lb* Unlrenlty orPennayltania, wbo boa endeaief ad
10 render the work tv\\j up In the day, and aa naefnl tnlba Araer<<>an phytielsn ae II ha* proved
to he to hii KnRliah brethren. Tha nnmbar of llluatrBtiona baa aim been largaly Inoraaaad. aod
BO effarl spared to render the typngrapbiaal eieootlon anenepilnnabla In erery ir(p*4t.
'■RiyanliB' Bytiem nf Uedlalae" U JRilly a«n-
•lilerad (b* mHipapDiirworkaa Ibe prlulpJai and
^raellee of medlelaa ta lb* BBgllili lnogaai* Tha
p..imn„rrtnii-oi;;r ■■!
pi«tdhy«oirt.i. >- p..
»■"■'" •)'l'"''°;.'|:
I
I
■ ■ ■ ■ -lie baiy praell- 1 aa aia.'aBI at 1' "
laaye aa pVaeiUal*> p-iaiUlii, end wbUe ib»* •*•
HxNKT C. Lea's 8oh A Co.'s Publioattomb — (Nero. Dia., Ao.}.
1 Xftl. Onll nfPIHIt,^t
A PBACTICAI. TREATISE OX ELKCTRICITY IX !T3 APPLI.
CATION TO MEDICINE. Scoonl Elilinn. In one tsry b-ndioai*
SOS pag*i, wiUi ion Ill'i.lriilini)!. Clolh. %i SB. (Jna R'ady.)
tnou TH» Pmirjic* to th* Siicokb Bditio*.
In Ibe prMFnt ritltinn I h»( innd* manj aililUlnni Hud iinpraTFDtnl* to randrr tb* *ork
moit utcful (» thine for wliom U ii inUndoH. At Ihe iiaia t1m<. in rfpor
D>r«n lniTr*nFln;t i<«tre ririnftntiSo trfSCmrnt. I bkra dtrelop*'! arntt full?
of (iKFtUininK miH •iprmffme ourr»nl itnnclh, Isotton. rBfUtnnMi, •to.
nun (ull; Into ih« polar intthod, Hod into tha ■elinn and Ofsf of tbf mAgnit. NulolttuMnd-
inv mn inetcuB in tb« nnmbar nf I1n« la ihe piK*. und tha snndanolinn of lb* isatttr naw aad
014, lh« wurk hiia b>aD anUrt^d b} thv addilion of Ibirij pngrs. Tbo* ImpniTed, I nar b*
pamilted le hop* tbtt tha ni« gdiUDn will eonllnue to onjoj tba bror ao larealy batiowad «■
lb* Ural.
Tha KooBdajrtBBartbl* work bllDif lug »>cioB , ptete »l
Bpai Ika Unl arnold la ilMlf ap|iur In la a •□■- | appltiai
» main
lina.« for' "VdMU iad p'f "lIl'^V.' ("lb", i "^l "".I'^iaT'lu; T." ^dWllf* S^f.^V*'
.ohi.fr, ..r hitlat dm. «.>. «nd ihal afl-r a llin. i^" h" ^b^Ta'fcr'Mb'r b J '"ihl*^"" »
Ih.It knowltdia a>wf MfrMdlng. W. tbigk ha ,,,,„ o( ,b, ,rt,»M, 11 raa Is •«?»•»/
aalanlauii. bgl l> Iheroartlr P'»«ll">. .i-pla. ' IL"a"MibU mMoi-'plTon Tila fo™ of tb.
aonpl-.a isd cnuvrahaoillila li ■■, mor.oroi. ra- i tu..^y.j. „atf gurg. Bf-'i'r, >o». 1 1»1
TitrrrHELL (S. WEIJt). »d .
LKCTUIIES OX niSEASES OF THE XERVOUS SYSTEM,
ESPBCIALLT IN WOMEN.
'■buDiSSOpi
iPr,
ring.)
ttry bandaoma llmii. i
Thalifa.lc
amlbrntl; I'cairabia IhnI tha ruulla of bit
wbo maj ciparirtKe tba liiffioDltiu annni
linna his li.iri bava nBdafjjone in reicard t<i
wfanle work ha baa baen enraful In kaap in
A fa* nolioes of tb* prarioBa edition an
phfaiol laical kad ihanpaallcal It 1. a' hoal
U kr.r.rical. naji •all lars vlib • >.ll-(io*a
I.' y^l! Tim°" ' " """ ■ •""'""
•eo diacnaaad
la tbii TO
abDoldbaaul
Ddied fo
•itb the Ireal
mont of
i ottaara
Jia praotionl le«
touofh
■ laTiaaiaouBlor
Dt llllahall baa
naiia.aailr.iiGBaiidp
hlMMMMk
fJAMlLTOS (ALLAN MrLAXE). M.D..
. ^rKfiUpllf ••■'I ParaljilUt. BlactmU-t /f/aad. S. I..
dii'i niiixuni-'nrmi. iiriiirim'Kl '•/ thi Vne Tirk Htftl").
SERVQl'SDISEASE8;THKIR DESCRIPTION ASDTKEATMKNT.
Ennnd EdilloD, thorasftbl; rairia.d and r«irril(*n. In ana handinne usIhto leluna af
tSfl p*«ai. with Tl illuaUationf. Cloth, (4. (Jml lUaJg.)
IT. are ill"" ■- - ■
••aTal a w»f
Hknkv C. Lea's Son k Co.'s Tv'aiAot^'i\ttiih-^IHa.oftkeSkin,Ao.). 19
'ORRIS [MALCOLM). MJi..
JMnt Imclitrtrot Ita'ifinf'.ln^, SI. Mtrg't Bifpilat JTtd. M-iot.
SKIN DISEASES, Indu'liii!^ their Definitions. Svmptoms, Dinsnosis,
ProffiiDiii, Morbid Aailnraj and Treaimant. A HannnI for 6tad*nt>' Bad Prislitlonan.
iDOMllBO.TolDmaofaTaraoaiwsu.withlllBrtrBtioni. Crotb. (1 TA.
inrdloaaUn-aiaiHl.wiuaLiolwiBcIf i ptuBuH ■ ndoaBl ODnMpona o' dwniMlolotf. ■
.bUIUIItbuokor Dr. Kurcla. Thfufca- i briiiiib aoBr*H«dlT 4ISaiill tD' pe>|<'ri»f id lb*
.tmixtili-urthadliikMni, >netdn>a- \^t\t%n.~Bl. lanlt Onritr «/ If-iUctHw, April.
fjvDE (J. xE\'iss). m.d::
■* *■ Pr-fftnr of S>trmiur<\oin tnW
irrii, iBSfl,
po.
Pro/uittr of DtrmiuMnn ■'•"' IVaim/ DImmi) <k Jtub MvHral i^Ue*, Okuaffa.
A PRAfTICAL TltKATISB ON DISEASES OF TRB SKIN. For
lh> Vtf or SludtnK and Prwiitionarc In on* hoDdioma ooUvo *ol«me of b'O tW|C**>
with AA UiDilfBl ud sUboril* illurttnlioDi. Clolb, St ti; iMtbec, %& IS. (Jiijl
JC iT/LBVRD. M n.F.R.rp.^nid T.'c. FOX. B.A.. M.R.C.S.,
AN EPITOME OF SKIX DISEASES. WITH FORMITL.E. Poa
ertiDiaTS ARn Pbactitiokkbr. Tbitd Kdillon, ■ptcU11<r mind by llio Aatbor. and
greatlj onlntKrd. la one varr b'ndaoinB I2m.i. inlume. (PirfUriHg.)
IPLINT (A USTIX). M.D..
*■ PT'l/rtfT n/(*. Prtmctpl'so-,11 Fractitt of IT'rfldfiM *■ KrlUwAt Biftlal »«<. <?i>"«««. f r.
A MANUAL OF AUSCULTATION AND PEUCUBSION ; of Uie
Pb^iieil magnaxlF of Dlieiirtn nflbe Langr and Ilnuct. and nf Thnrnele Anearlim.
Third Kdiilon. Tn one baDdKOme rnjajjtmo. toIobib. (JVMr/y Hiady.)
JtT TBVaAMK AOTIIOrt ~~
PHYSICAL EXPLORATION' OF THE LUNGS BY MEANS OF
AUSCULTATION AND PERCUB-'ION. ThtM Iwlnraa dali.erod brfor. Iha Philadrl-
pbia GoDDtj Madloal Soeifll^. IBSZ-IBH3. In on bandioma rnall ISao. Taluoia of 8S
|WgB«. Cloth. (I 00, ^JaU Riadf.J^
gr rUK SAKE AUTBOK.
PHTHISIS: ITS MORBID ANATOMY, ETIOLOGY. SYMPTOM-
ATIC EVENTS AND COMPLICATIONS. FATALITY AKB PROOSOBIS. TBKAT-
MBNT AKD PIIY.«ICAL DIAGNOSIS ; in • »rlfr of Clinical Stndi** Bj AciTia
Fi.1ST.«.D.,Prof nflhePrinripl««nBdPriiBlica.>fMrdipini.1n Bfirevua II' •pilol Med-
ical ColleEi, New tork. In one haDd^oXBt ncr*>o Tolume of US pages. Cloth, t3 it.
n T THS SA VB J UTHOH.
A PRACTIOALTREATISE ON THE DIAGNOSIS, PATHOLOGY
AND TREATMENT OP DISBASBS OP TUB HRART Sf-od r"»i-»d >ind enlarge*
E'tllion. Inonao?taTOTolaiiiaor»SDpag«. withapUte. Clotb, S4.
n r THE Sa mf a uthor "
A PRACTICAL TREATISE ON THE PHYSICAL EXPLORA-
TION OF TUB CHEST AND THE DIAGNOSIS OF DISEASES AFKKCTINO TIIK
RESPIRATOH.V OBOANS. SHoadaod Rgviaed Edition. In on* baudaomrofltaio isl
unenrsSl pagH. Cleth, (d &fl.
ROWNE {LENNOX). F.R.O.S. Ed..
" ■ ~ ' [,-nilnn Thrvat atuf gar Bnfptlal, Me.
THE THROAT AND ITS DISEASES. Seor-ml Amerk-an, Tiom Uie
Second English Editlna. tbornnfM; rerlaad. With one bundrad t; planl IMaitMtiont In
colnrt. and ttlj wood rnj^taviiigr. imgati and eUfcaled by (ba author. In one Tcrj
handnoina Imperial aalaio Talume of nboal HCi pagaa. < Pnparing. )
'EllER (CARL). M.D..
.... ■ .. ..^ rrtlvrtl'v/ '''■ni'vl-fila, Ohl^u/tJu Thr-al Di-ptn-
A HANDBOOK OF DIAGNOSIS AND TREATMENT OF DISKASKS
op THE TBROAT, NOSB AND NASO-PITARYNX. Beoond Edition. In one hand-
■OBierojal Ilmo. tdI. oraboDl ISO pagta. witb about SO iiliutratioDI. iNfarly Rta<lg.\
wiuon-s BTnoEKT's book or cutani
B
S'
so HiKBT C. Lba*s Soir ft Co.'8 Pubuoatiors — ( Venenal B
rioiisiL {I'.).
SYPHFLIS. ITS MOHBID ANATOMV. IHAfJXOSIS ANDTRRAT-
UENT SpfOiillr rrriffd bjr tba AoUinr. m4 trmnilkleil wilb dsi** ■■4 »441tlau b^ X
~ ' nil, UD, DamOBitrMarurPiUhnlnitMiiil HiXDl'-rrla the CnWtriitf <-r P<
SuFEtOD to Ibe SplfOopkl Huiplul. Philodtijpliis, kod J. WiuiiM Warn.
ir nn V*ii>ra*l ■>!•«*•■ Bncl Dimnnrtrilur nf Sartnr; in U>a Dninnilji «S
■Bil SnrsMD Ul ih* PhlladtlpbU II«pilaI In tut htnitniat o«lSTa TotaMt
of «BI pBgci. vUbetTirjbaiiDtirullllaitriilioni delh, $r-- - ~ ■
-——- -tlimrpt ■- — '---
asri:..'
■ ill.aU* I
I tadic*i>4 by ki
•l«|1Ml
rlioiil a id AUrf rsiil AfxHir. Auf. S
■ l^itVfi
• iIIBar.
•DhJK:
T.-J"
i;^.; ,..,.. ■:;S:S
>r*>iilti.— Lmdao JTet n«H wtrf Mk. K>'. tij
-jrttr|il<in<< Jl-d. i/»n>. Aof U. U«
OnUSTBAD (F. J.). M.I>.:lL1>.. and /TAYLOR (B- W.]. AJU.. M.Dh.
f!«ll .,f PKft qmdS -— '--- — .....'.- _*.__^.
THE PATHOLOGY AND TREATMEXT'OF VES'ERliAL.'DlS.
BA
3B8-
ladudingib
001
Ar»»ir
nlic*
of reuat tutulisatlou
liOil
e Inr
■nd b
■tiki %Ai. \t ibor* )• a baitoi Is .ar "iVr lasf ua ' 7;/,;; fc^,. , :
». taaaat a...i<; tliaf* ar* «ri.ialy a-^h™ii. >a ' f",^, „.„',.,..
Ih*»aal«..al .f iha »»ri.q. .,.o.[.llM'l.>a. n? »».rr ^ ."
.n.r«l alwM W. I.ka fl'uar. la r.|«.liB« ! *'■«
pwUaL
I
I
L PRACTICAL TRRATISK ON IMCOTENCB. STEBILITV
AND ALLIED DISORDEaa OF THB MALE SKXDAL OtiaANlj. In ooa
•DO* a«taTO folam* or ISA |weM. "itb 11 illailrallnna.
ffULLEHIBR {A.).
V/ SurfffOt Is Ik, Utpll« 1 1<
f.'.f.tl^J<*J'
JM-. i»
and DDMSTEAO {F. J.). M.D., ££,./)„
;.)H !</ PhKlrlg'.t -Hi S.rjwu. Jf. r - -™
AN ATI.AR OF VENEREAL DISEASES. Tianslnletl amlEailir.i bj
r*l>HA> J BcHiTSAD. la one l&rKc iin)>i>rial (lo. •oIbdi* o(»iS pa|;M, <l«Ua-«olnBB(.
■lib I* ptil**, coDtnining alioDt liO BBUTea.beaalirDtlTqolnrcd. naa; of lb*m th*(t*a*l
Ufa, Slrnogly bnond iniliUb. |I7 0« i aUo. in fl<* parli. tlanlwrapprM. II fS t*r put.
A ipTrlni'ii of tfae pUtvi and tfXt arDl rree b? mlJI. ud rafclpt of 3& ecBU.
LSBii Lto-Ti'HSB oa aTPiiiL's akd wijisi bii.lon syphilis 411D LOCAL cosTiaiavt
roans iiF_LiinAl,l>ISB*SK*FfBl^TI»IOPH|ll-| ■
Claih,tlta.
Hbnkt C. Lba*8 Soa i Co.*8 Publigatiohs — {DU. of Children^ Sc). 81
GMITH (J. LEWIS). M.D..
A COMPLETE PRACTICAL TREATISE ON THE DISEASES OF
CHILDRFy. FiOh EditioB. thoroapbtr reTin^ and rewrittvii. In one haB>')ii'!MBe o<*-
Uto Tolmne of 8^ paf^'- with iltsMrationt. Cloth. $4 50: leather, $i 50: rery hand-
fome half Ra«>ia, rabed band;. $A.
Ti.«: fc >» •>* pr>f»*# tf trt !r*at of d*»«a*e« of cb'l- wb'eb tbitots* trniTPtbat U Itteqva! !» ra'r:* ?<» tb«
drcr ih-^ald biT« r««e're^ aflfsa editUa i* io !t*e!f rbrMrian. Wh:> he ba« ftmli fo*t escci;^ i'* impart
f&lr •▼.d*iic« of i« vonh. the a^^re e^periaily a> It ibe tarornikti «a deur^d bj feaeral f nc::*f >cer» «a
ba« 3At tb« 0e;d t'*^ itteIC bnt ba« to compete vltk ^^acb qne»t!>>at a« ettAlocr, p«th;«!<HrT<. JV^fB^^N
terefAl other ex^•llf^t Baaaa!*. The rbapter oa etc , be ha« devcK^i more atteatloa t.** :h« i\A€9 »ia
Rarb!t:« \* exreiies;. aad v«li np to ibe dav-a re- tad treatmeat of The Ailmect* vhleb he «>> leea-
mark vhlrh sar w-.tb eqoal jaailce be app ied to raely de^er-be*. aad *nrb iaforKati''D )* ex«r*W
Ibe cb«?*er An $:r -fala. vhieb 1* one of tbe he*l we vbal it vaaied br ibe Ta*t n*ai.^ritj of ''ffevilj
rtmember o bireread Tbe di«ea*ef> of the aerva* pby^lclaa* " — VirpiHi-i Mtl. X--n!kif. Feb. 1>>^.
•y»iem »t. we:! de-erlbed. aad •« f^r t W ra^.t part j^^ Mj^r^xnnet of a Iftb edltioa of tbia work U
are tb-^ -f ibe aac*. Dr. >«»!b w.^ald "rw^r t > ,n«^i,,, ftU-.Uli<-a of it* irrea* ealae lo ibe prae.
ba qa: * -i- ro^^T.' with tbe wnk <»7* oa thU ^ide t,t,^,„, .,f 4^0 coaarry. a-d of tbo a«e iber ara
ofthe w..r}d.mBireferaf*el.rTobafli*bandfore1«a ^,,^^^ |.» „»ke -^f It. ra^ceiioaab y I: t* ib«
•atb r. a.wella*top*rt^JraUeM.«rt.l yderoieJ ,^,. ^^^^ .>a tbe maiadie*of cbiUbox>d ia :h* Ka|h
to <l»-.i'.eaa di^aea -ArtfM* M*dieulJ^ur»uL :i»b Ucct-x^, aad la »ay foreca .aa«a»<? w^ kaew
a»y <?, 1>>-. ,,f ^^ ^^„lj ^fcteii iriJI compare wiib tt Thti tha
Dr. -^mitb i« a c»r»fal .^b-*rT*r Had pala«tablng flfrh Hiti^a ha* beea tbor.-Bcbly rfrUei aad
wr'i*r. He b«» eaJTeJ cn::^ual far^Iiito* wb'cb Sroqfroi ap *o data aa a-teaTive or er«iD car'le**)
woalJ ^a-b)e bim td vr::e ■ prac.lcai acd a^efal p*rui>«I wll!abanliiBilTdi«cl t»e.— ?j«<iJi in/i>«r-
bo ik, a 9-1 :tjL: b» b ■• anr reeded :• atteMeJ St the m»i *\f MhI ScUnc*. Feb. :9f2.
app*j.r-i3r* f-^r.-e^^^rp^diiia-ofbiiiwork. Tbere jv^^ impr^Tomeat* ifcat baea beea added briag
if BO J n-: : 3: •::»• ;: wi:i 1 .ex r^ra.n lt» place a» a j^^^ ^^^k falW ahrea»t of ihe ime<i. Wo caa ai^ar«
•tandarl :-«: b - i amorf Mad»a»* aad prmc iti.^a- ^^j. r^i^r* l'b*t :h*y caa procure ao better work
er* —A: 'nri% Air./*/ ./<*,f,fr,r#. Jaa 1»1. .,B tnfaacy aod e^:iI,ibo.vl fir reVr.nce aad •tody
Tber*> > b< V.*<»k pd>-lt>b-^d .'a tbe aabject* '-^f tbaa ibi« one — t'*ii«c<>«na.'< Jf<«l. .ViIM, Jaa. Is6i.
ITFA TISO JOHX MX 31.D.,
THE MOTHERS GUIDE IN THE MANAGEMENT AND FEED-
ING OF INFANTS. In one handecme llmo. rolame of 118 pagM. Cloth, $1 00.
Tbe i'.e of 'lii<^ Utile b<-i«>k !k wall cbe#ea. ard Dr atraccaf tb#ia oa the i^nbject* here dw^I: np^a ao
Kea:.c£ b-» writ-en a w)rk wb'cb ^llOnld be r«ad, tboroccblj and practically. Dr K^tiag b«* vrit-
aad ::• ^ir^c^pm f.»llow^d »-y ct^tt {ut<>IH|ceBt mo- tea a pract'.c^I b-»ok. ba« carffaUT aroid»d nnae-
(her :a '. :« c<>'.<ntry. It i<< free from all technical eei^fary r#p*r tion. aad. I think. '^acce^ofnry la-
term*, the laa^aafce i« clear and di»tiact, and a>» »irncted the mother la »neb detalU>f the treaimcat
earef^lLT 'riiiea th^it it cauno*. f^it to bec«ime pupa- of ber chLd a« doTwlre apoa ber; be ha« ^ta-U ufly
lar. 1: t*»^ ilvay* he^-o a m«oted qae^tioa how far omitted firiag pratcript'.oBA. and la»trac » ibe mo-
lt i* w^'.i t instruct ihe 1 abl-.c. ba: worku like this 'her when :o call Qp>»a the doct >r. a* bia ilat:e)> ara
eae w:.I «'d tbe |»by»iciaa immee#ely, r>r it nare* lotmlly il'.«>;)Dct from b'-ra. — Jmerfciin Journal v/
the time be i« constantly ^irirg hi« patif-nt* la la- Ohft*trira October 1SS1.
AMSBOTHAM lFHASCISH')7irL
THE PRINCIPLES AND PRACTICE OF OBSTETRIC MEDL
CINE AND SrRQERT, in Reference to the Procew of Parturition. X new and enlar^red
Edition, thoroughly revised by the aathor. With additions hy W. Y. Kbativo, M. D.,
Professor of Obstetrics. Ac., in the Jefferson Medical College, Philadelphia. In one I *rffe
and handsome imperial oetaro volume of 640 paces, with sixty-four beautiful platei*, and
numerous wood-cuts in the text, eontaininr in all nearly SOO large aad beautiful flisures.
Strongly bound in leather, with raised bands. $7 00
WEST l CHARLES), M.D~
^ ^ Phvnician to the U^^pitaf/nr Sick CkUdrtn, Ltmdnn, *c
LECTURES ON THE DISEASES OF INFANCY AND CHILD-
HOOD. Fifth American from the Sixth revised aifd enlarged English Edition. In one large
and handsome octavo volume of 686 pages. Cloth. $4 60 ; leather, $5 50.
gT THE SAME AUTHOR • Lately htnudA
ON SOME DISORDERS OF THE NERVOUS SYSTEM IN CHILD-
HOOD : being the Lumleian Lectures delivered at the Royal College of Physicians of
London, in March. 1871. In one volume, small ISmo. Cloth. $1 00.
g T THE SA ME A CTHOR.
LECTURES ON THE DISEASES OF WOMEN. Third American,
from the Third London Edition. la oae oetavo volume of about 560 pagea. Cloth,
t3 75: leather. $4 76.
rXCKEL (F,),
E
W
A COMPLETE TREATISE ON THE PATHOLOGY AND
TREATMENT OF CHILDBED, for Students and Practitioners. Translated, with
tbe consent ofthe author, from the Second German Bdition, by Jambs Read Cbadwiok,
M.D. In one ootavo volume of 484 pagot- Cloth, $4 00.
SMITH'S PRACTICAL TRBaTISB 09 THB WAST- I Seeoad Aneriean. from tbe Second Bacllah Sdl-
IliQ DISKA8ES OF IHFAJICT AX D CHILDHOOD. | Uoa. la oaeoctavo voluma. Cloth, fSM.
32 IlENitT C. Lea's Son & Go.'s Publioatiorb— (Z)u. of Women).
rpHOMAS {T.GA!LLARD),M.D..
■*■ PrufrMnri:/ Otifliirti-K. Sr.. la lllr OnthB' nj
11/ P/iI/'rutaiit and Svrseotui. If . T,.^c
A PRACTICAL TREATISE0NTHEDISEA8ES0FW0MEN. Finb
Kdition, (boroughl; rcTifed and rcwritlno. In ona latgfl and h«Ddaaine octaTO toluiM
of SIO piEft, wUh !«e IKuairMionL Clalb, t&i l«ath*r, ft: *>r} bandMin* btlf
RnniU, TBitfd bunds, fS SO.
Tb«
•aii.iiu>r*n>ri»*l>ag>
■ i>d>d<IUI»D*>l>lc>ib>
iklllix
• ind irath it Ibi elliUil dwrlpiloK at dli
i<^ Ita* hrilllLir arili* mihoi In cter^paollc n-
n»n aad Ihi FbIhu *l>b >hl()i lb. Atulli ul
>lin>B( an dtitDbad : ifa« lalliilKi ohirutar ol
dor whieli p«nf»dm 11 W» •onid' »1« ptrtica
r iBitFnllig *ad (Ifaa 11 Tail* at k vorli ng
l>ta til* .iwiflbur t,.i
(■.aLlilhit.ll W.jiidgmpo
Wa inlT wlab thai
An >Hai|nillagaCIU*irark will vro»lhalUI< ' thai bl'a <ttn>td>1
naaurfr-al nrrtl. It I- Dt.1 a mrro con pi 1 alios oai su oncalra nf
rroD ntbtr wnrUi. tint It lb> Irglt ill ilia tlpa lUuiou-thaDpaatl
tbODghi, •ua<id Jndiiaaot, aodarfllciLubietniluoi ojclop«dl.ijt«r»i«"- . - - -■- i-
ksoTliidga At Iha dtparlogat of nadlclaa lo vMoh ; •olijael )• Iraalad. and Iha kuaaal niaTlalloa* jX
U !■ dornied la ll« praMat »Tltad itala U ear- titri (rem M.ibahir Iha l.r^nU alltlut aitpartBaMtl
lalil^botj. ari>»n»»t popdlloa aa ■ nDBcnlgjIeal In thai apatlall^ oraiir U lW> «oo»l»/.*ll ■•"•IR
f^VNECOLOaiCAL TRANSACTIOSS. Vol VI.
VOLUME VI. {JhsI flwrfy) Containa Essays by Doctors W. II. By-
ford, B. 0. BoBSy, II. J Onrrignia. 0. H, Ljraan, Nillian'BoMman, E. Van da Waf-
Vw, I. E. Taylnr, W. Hn^idall, 0. P, Campball. T. O. Thoman T A Raamj. A. U.
Bmith, A. D. 8iD<-la1r. J. W. tindarbill, B W. Janha, LL.D., W. H. Polk. W. R. QlUdU,
C. C. Lae, F. P. Foalar. R. W. S.iwyar and B. B. Braniia,
Wilh [ndaxea: idLofVol Vt.; |A|. of lb* Grnnnlngieitl and Ohilalrifl Lllaralnr* af
■II Co Ml trial for Iha Ya*r IBSO; (e). ot Obllatrla and Qjiinnl'igieal Jnurnalt. and [4}
of Obitatrip and CI;rn««nlo|{<<i'>l Soaiatlai.
Tfaa lix xilnniaa gongilatlng tha lerlaa will ba aant h; tnall po-lp>id on rawtpl nf tit,
DT if ilngra aopiu ara datirad Ihe; lalll ba rnrniahad at tlit rxU of *& nub. uoBpUBCI
Vol, II. for tbe jaar 18T7, the pt\ft at wbich ia (S^O.
^D/S {A
ARTHUR W.). M.D. L'md., F.R.G.F.. U R.C.S..
\c ph„.f,
u Phf-u
[:ir Palliolofty, C'uisft<
THE DISEASES OF WOMEN. Including lit
lion, S/mptaaa, Diagnotia and Traalmtot. A manaal (or BtodatiM and Pnwlitlanart.
lDaDaband*DiDaMMaTOioldn(or67e|)agei, with lis 111 ut. Clalb, $1; laUbar, t4-
a«*«( UDi*, aiiirilaaitDR »f latoliaa, and a>a * bi
valar Igjacilaaa. Tbaaa ar* anoDg Iba mm (oi
Dinn matboda ol ItaalnaDl. aad T>t Tar; III>1a
■aid ahoat than la uaar i>r >ha taxi-bsoki T
baak ladaalo ba vamlj raoommandcd. eapacUllr
■ lodHBla and naaral praallllaaari. who n*'d a an
atiabatQninpfatar^iuaitorihaHlieiafDbJaiii, tf
da.7;,d<:^
balBK tall/ aapliiaad Th- A—irt
rac. am la ihla baak ika kind at k
"'•-••"-«•
DARNH-t IROBKRT), M-D.. F.R.C.P..
A CLINICAL EXPOSITTOX OF THE MEDICAL AND 81TR01-
CAL diseases of women. In ona hnndaoma oflU*o voUme, witk aaM*r««
fJODQE (RCaa L.). if.D..
In Uu ITntoiraMp n/ PmnavJunta,
ON DISEASES PECULIAR TO WOMEN; including Displnoeniont
af tba Cleraa. I^amind BJUt»n, raiiaad and sntantad. In nna haaallfally prlala
MlaTofoiniDB of tl« pBKai. ■itb Briginalillaatratlopa. Clntb. $4 &0.
f
IIknrt C. Lia's Bon & Co.'b Publioatiomb — {IHe.of Women). SS
TPMMET ( THOMAS ADDIS). M.D., I,L P..
-*-' «..ri,™i la Ih. W^mani H^rpilat. Nr» For*, tr.
THR riU.NCIPLRSAND PRACTTCR OF OYN.ECOLOOy. Tor Ihe
ma ur Stadenli Hud PrsBtiKDaeri of Modlalne. Brnnnd Edillan. ThamoghlT Riiiwd.
In on* lArg« and ¥117 handfom* oetnTo vnlmni at 8T9 paKsa, wftb I3S illnilrstions.
CLotb. )&i IsMhar, |B ; hklf Hauia. raliad bftndt. (0 tn.
° " '" ''*" ".Vr'« 6r°»l7 'r«f""uw«lli'« 'o''ISiI'fiMlIl
HlmMntil,— f^ktmoo Wrd 0M., AprlK,IMI
Tbi wldarapiiLslloa sf Ibaaiilbor naliailiiM^-
r^iddl
11 aatmt'.—nni. nm. /<»•>
ifBllT •IIIIM* Had (n-nuBnll; toB-
•liuptMllMlMtt ' -•
la —L->n<t. MtA'TtaufanaOat .Sma \0A
racaat votk apog taj •abjael'bu ul'ifixd igeti
en-Hi popaUrllf •« roMIr *• ■ ""'fc nf (•l«t»l
.■rB*n>- Mar. I'W.
J^N AMERICAN SYSTEM OF GYNJRCOLOGY.
A SYSTEM OF OYN-ECOLOGY IN TREATISES BY VARIOUS
AUIUOKS. l/n Ariiet PnifaTntian.\
nUNCAN (J. MATTHEWS). M.O.. LL.D., F.R.S.E..etc.
CLINICAL LECTURES ON THE DISEASES OF WX)MEN,
De'ivacrd In Snini BnrlbDlanaw'c ItDt|i[la). Iq ona bandiDma ooIrto Tolnma of ITS
pseaa. Clolb, U tit.
I' li.idled ta ih<I>iii-boi>k>;u<l»r>|»>r»<j «t ib< sw
>mtntt apna ioi>>» lb*t an a>»llr | Minb, IBM.
r r JTuJ. Jotr* ,
h III
J>AHRr {JOHN S.). M v..
EXTKA-UTERIXE PREGNANCY: ITS CLINICAL UiyrORY,
PIAtiNOSIS, PROONOEIR AND TRKATUENI. In one haDdnamc ootaTO loluiDa
oflTSpagat. Clotb,»3ifl.
mANNEK {.THOMAH H.]. U.D.
ONTHESIGNS ANDDTSKARESOFPREGNANCr. Fim An-rnMn
rrom tbi SaaoDd »ad BnUrBad Bngltib Edllloa. With fanr coforfd plat** and )lln<t»-
linna nn vnnd. Id nne bandiDDKi ni-tMio Tnlnma of about ifit pace). Cloth, t^ %i.
•flUSSEKOW (A.\.
't* /--./-.dr../ JfJrfiM/n
"K DU-
A PRACTICAL TKEATISK ON UTERINE TUMORS. Specialty
r«ii»d by Ihc Antbor, and Icanilutod wilb Notn and Addlllonf ij EoiiiiKn C. WniiDt,
M D.. PaihAloptirt la tba St Franela tlnipital. N. Y., a'r., and rEviud by K*th<mi
B»i»d. U.l>.. SurjErnn lo iba Won.n'i )lc»r.llRl onha Etais of If** Vork. In oiia
bandjocna oota.o Toluma, witb nbouHO illualratiom. iPrrpariHg )
ffHAD WICK {JAMES H.). A.M.. M.D.
A MANUAL OF TUK DISEASES PRCULTAR TO WOMEN. lo <>»•,
bandaama rojal ISmo. voliima. with illoatraUooa. {PTtpariitg.'i
l.UN TREPDEKPttRALPETRS AKD
LxBASKi^PBnnr.jjiMTo wonuM. ■■
iToinniar unpatu. Oloih.OlO.
tn% Hatdrb. Klaus Ann riiSAT
CHILDBED eRVBB taxaa «ni.1al.
(rom tha Third 4Bd ra*1*id Liadni* Bdllloa. In
aaalTo. .-■., pp s«. Cielb.fUCfl.
■Ki^Olll
Hf^oMS ovpKiatfisrT
I
I
94 Henrv C. Lea'b Son & Co.'s PDfiLiOATiOK8—(Jlf idm/rry).
iElSHMAN ( WILLIAM). M.D.,
A SYSTEM OF MJDWIFKRY, INCLUDING THE DISEASES OF]
FREOHANCT AND TKK PUERPERAL STATIC. Tbirri Ain.rigiD Edition. nriM.
tha Author, with iiddltioDi bj JoDH B. PjkHBr, U.D., ObatetHolsn to Ihi PMliu)?!
Iloipitnl, Ifl, In Dii>^ large ind Tcrf hnndsnoia ocUvo Tatana, of 740 pitg«, witb'tH'l
illil(t»(iOD(. Cloth. 11 lU; lantber. SSiUi li.lfRoia)a.«S.
rtblruUfiH.!-
p£,j4 YFAIR ( tV. S). JIf.O.. F.ii.C-P..
A. Pruf-itOT'trCi^HHt UtdUiymli Ktnet OalUgr..ac. H'.
A TRKATISEON THE SCIRNCE AND PRACTIflF: OF MIDWTFERt. '
Third Ameriesn Editian, rcTiiad hj the ftathor. Sditad, wUb idditionii. hy RoMKr P.
UiiMia. M.D, In ddb bandtotaa celavo Tolume of 86« piigM, »jtb 18) UtnstraUoai.
Cloth, ft: leithar. S& ; bilf Rutfis. ti iO-
Th* •■lil«l li tlktn Bpirlili iniHier ti»d. The ihlBg»M»»lil«r*d. wt r.(*rS IW.t
KtldaTolad laliborlBnlMImrliiuanrusaliUDaii. ; M<1 «■ M14irtr>r)r l« Ik* KnfUak
gMaBa^naalaadrafoIra, U>dalrcblT>rra*(a-l.l Ml^halJn^rivtl,ll»j, iSM.
•Bd IhaTtawiietartllaadwUI bafbaadauaalliJlT ' n sarMlalj !• an adnlrMM* •<
BiodatB, BBd 111* oplalnai tjcfnaxd irii<il*iirlbr i Solanat Bad Pnuotaa af Ulu v
Tha Hnrl ahnnaili wuh pUiH. Illudrailag nrloui I addirinu mm-a. h> ik. a....
>: IberBraadiBlrBblr 'roajht. a.r
Bad tStti
J wro«ht,
■ et trsM r»imt.—7^ Jtntrir
nr TBE sjxB jiTTHos ' ' ~"
THE SYSTEMATIC TREATMENT OF MRRVE PROSTKATIOll
AND HYSTERIA. Ib ooe hmBdiama (hibI] lima, rolame. of ST pagas. Cloth, fl 0^
). M.O..
ind D tmtEt a/ tCnam In ■*> Mtdieal fiipnTlnunl iftkt Ct
A MANUAL OF OBSTETRICS. In one very Imiulsome 1 8010. vol
ama of 311 pagaa, with &6 illDatrB^ona. Ototh. 13. {Jut Btadf.)
aab|aelBUii»n|'lirf<r>g1fliBU. aad Iklilx ek>flT ' to tla4 > riiumt of la forma Hob b^
evUfla a dlioolaaH of aipraHloa, aad as btdiJ- •sbjoit. II wlllba SCfanbu •bIbbIo >l
t>. br rBB|*d ror rararaata, Iio>B( wall (itrtfiaykiid. WBk
*al(bl at (
JadiaaB
jB
irKj, I
'a taata. lb* book la
»ff»il Whila. .
J>ARNES (FANCOVHT). M.D.,
AJ PkyafffMH M r*i Ofum I hvi^g-i<i B
K TtARVIN (THEOPHILUS). H.D.. LL.D.
H -* Pt^.-^IAtUlrUtaMd^/ttf M-'i-aiut Surg. Ou
■ A TREATISE ON MIDWIFERY. In
A MAXTTAI. OF MIDWIFERY FOR MIDWIYES AND MRDICA
STUDBSTd. Wiih BO llla.lritioi " " '
$1 «. (Lau/f /•.««<.)
fJODGK {HUOH L.). M.D..
THE PRINCIPLES AND PRACTICE OF OBSTETRICS. IIli
iratad vllh Ibi^ tithogiBphic plale* eontaioiag ena hoadrod cad Rftf-alav tf^tftnm
' ■ '- - 'arft Bad h'autirBlli printed
..!ln-l"th,»M
(obb; BddroM.rr**bjM*i),
oau 0/ tr-HMK <• ■*• ^l•^. iWJ. a/f s^Ivn^^H
In one v«ry tifinilsome octa.t^H
U^tioBl. { FttpariMg) ^^M
MIDWIYES AND MRD(CAI^|
a;al llmo. volamaoflOOpagM. OlOl^^H
itan-iitFo/rniutlMBla. *>. J^M
:e of obstetrics. iiid^H
origlanl photognph*. and with naman
I *• Sptefaeai of th* |
ElroBft'v I
D potlBga atBinVt.
HuiKT C. Lif's Sob ft Co.'b Publications — (Surgery).
TjAMII/rON [FRANK H.). M.D., LL.D.,
XJ lh.ryn.» Is Ik, S^lfmH H-'paal. Unr York.
A PRACTICAL TRKATISK ON FRACTURES AM> DISLOCA-
TIONS Biitb Editinn. (hornDEblr rvTiavd. ind mneb Improvrd. In on* isrj faiin<I>oB»
acUvo TolDD* r>t S«lf pajtH, with 393 tllaatrationi. Cloth, %i iO; l»lh«r, IB bOi baU
RuMi>. reiied bandi. (T DO. (Jiiil luwd.)
Id ihl< bi'Uk or inrft r; Thia vofk li ayiluiKlls
■DhiHi nitliT i-l»rlir mil loielhrjr in ib> ru^..
or ilgdiBt — Jfarw'a<ul JTad, /m>n>_ Kot
. .-bUc
'•B>(-
J SBBDRST {JOHN, Jr.], M.D..
THE PRINCIPLES AND PRACTICE OF SURGERY. Third
Idilion, (Diargid and rerlied. In eav rerjlarftr and handsnmi oatavti volume nl lOSO
isgfp. wfth SSS ninilrationi. Cloth, IB i Isalbvr, «! ; virj bBiiii>oii>a half &ll^>n■,
■iMd banda, «T SO. |.7k» fi»alv.)
iDlbor,
d«B*>il bm aoBptBbnilia dtieripUaa al Itaa nadai
»rpn*ll» ■owcaaBnlJjritBpUradln I)» Iraaimtal
.iilu la >Dq(l»:
mnu-
■ IKUmd.—Mid.
, Btt filllMi aiilioui >n HicadlBi Diillca otlit
1>0BRRTS {JOHN U.). A.M.. M.P..
J-'' Lf^«rrTi.nAnalcmyai<lonOptTnltttati'ff'TvalllH />Ml>i<l>li>Ma Sr*«ala/ Jsafsmy, nitow
••/ tki Ptmailtlplila Juadtm^ 1^ Vnrfftry, rh.
THE PRINCIPLES AND PRACTICE OF SUROERr. For tbe
Da* d( SlndBDta and PraBUlianari ot KcdMna and Smgirj. In one Ttry handaau*
a«Ufo TDlnDH Dfabont MO pngst, irltb many illnilrBtiona. {Frrparinf.l
,QTIMSON [LEWIS A.], B.A.. MM..
tJ /W-M.nr n/ FaUialiigUwl ^saf uny n( lA. DtliHrttlx aflht rlln •/ .v«w Tof*, Spif j<o« and Pnra-
for fo MtHcvai H:rpHul, SurgtuH to M> PTntVylrHan BatpUal. .Tiu Tart, its.
A PRACTICAL TRP.ATiSE ON FRACTURKS. in one veiy liai.rt-
■vna ootaro volama of 6S3 pagu, witb 360 baauliful iU mlf aljoua. CloU, tt I( ;
Isalbar, (A I&. (Jiuf Rtadf'>
la t>n.
gMh<
impaadloa
^'ri"*
«•>, (or
Wm*ly. Jan
Inlfuantad. TbajD4(.
nd *«*Bal*( rarnleoea
B a niiBii.f IbBfoi^Uj'
° A MANUAL OF OPERATIVE SURGERY. In onercry hnmlsome
TOfRlllmo. TolameoraboatAOOpagea, wUhaSIillnitrationii dath.lHSO.
tllaiinilxl Buanal. Tba aoiln.br a patualuf lb* iial>d,aB.1 ttaida>enptlsaJiar<<ta.>raad*cll diava.
work, vlLl sale a food Idaaof tbafiaaraldoiBatBul ll In a alarar and DatfQt idLiibi*; atarj ijadial
oparatlra adriarj, wbtla Iha ptacUcikl aargaoa haa •bnald pdaaati vaa Tba prapararLaa ar Ibl* irarb
(IblariirialbsUKiltndniatlappnTadatlaetloBior larfir vorkaaa taraarr for daaorlfllaaa ar opara-
wlib wblah Iha dlffarant oparaltDDi are daaertbtd bf Ib'a mr^vn irllbaai as tlibaril* a<
sj:
raailaal infatm
■*b i» <Ib«
railontaailittlKab*
malt IriMCU MiA OUli^i
I
I
Bkkrt C. Lea's Son & Co.'b PuBuoiTloNB — {Surgery).
/IKOHS {SAMUEL D.). M.D., LI,.D., D.C.L.. Oxvn... f.h.O., Cavlah.
A SYSTEM OF SURGERY: Palhologiual, Dingnoetio, Thpnipentia
kill) OiwtslW* flUtb eilltion, griM\j (alurgtii and Ihar<»i|;b1]' »Ti»d bj Iti* Aatbori
>nd StHUELW. Qbohb. A.m.. M.I)., Prufuiornf Ibo Hrii.aipl.t a[ E>irK*rj">i«l at Clini.
anl eurgcr} in Iha JxlTBrsos JCgdionl Collrxc. In (■» laritr and boulitollj prinli<l Inpt-
rt"l oUMtO TolnoiM iDalainine 21t(Z |Mgef, illuitriled b; 161.^ ■ngraTine* l^ttoDSlf
bnandio lutfair, r>l»i) biind>,$l&^ half Ruxki., roi.crt bi.ndi, SIS {Jft Rtadg )
Tb* nhjwl of thia wor
itforlh !i
rcHtlae i
. and ic
edition
ISSt. la 1
. coDoidir
I
I
rnnliDe of nlBlj. H; alui b
•Kirj tubject iu IrgitiiniiM c
dinU, Sprnial 11(101100 baj
cm* '(."'Tbi'i JuerlTMilw *jirbS
•'1. 1(1 Bcb >«id}> .Ed iwrMail >(p
. ii*. 111. f^'dkUi I'loq-ir idbirH I
IslndiHid, sod iiltu|tlb«r Itat di
ii^'^
FtrlM w. E.n |,ul^ H, ib.l hi*
.V"n"l.t(*°i'r l-V-liureld "u
l-Mnndflitld. Xt*.. Hot. I»^l!
•dlVih __^
pr rj«B sjjfs 4PTH0S.
A I'KACTICAL TREATISE ON THE OrSRASES, IN.IURIBCl
ftndMaltorcBBllaniiafib* Urinnt; Blbddgr.ehe Praitbt* •Hand ftnd tb* Uritbra, Tbifl
Bditlan, cboroDgblj rcTlnvd and maeb tondtneod, bj S*hdil W. Gkosii, H.D., Sar-
- < Philadelphia Huii|>iLal. In one haodxin* octaTo ruliimeor dT<Pibm, whk
Cloth, $4.60. I
■ I libnt) •li
li p I n pamn 1 1 1 lonlnr
AIH-PASSAflBS In 1 Tol. Svo, nilfa illa*tr«l[oat, pp. til. Clnth, St It.
noUiMAN (ALFBED). L.R-G'.P.; F.R.G.S-. Exnm. Llt-S-.eic.
^ afii.' D"il"l Siiryon 'lad Liclurir un Dtatal S-rifv IB SI. Biirth-lf-'i'-t Br.ti.Ual aW
A MANUAL* "■bF"''l>ENT A L SURflERY ANO PaTIIOLOOY.-
IhorDnghly rerij*! ind Bdapl.d lo Ibo art of Awtrioan MUiUnli, bj Tb>.u.« C. 8: "■
wacan, M.A-, M.O,, D I> B., Prof, of l-brnolouj al ths PbilDd*lpbi» DsDUl Cullegt.
00a hBiid>iiu«Tol<iniaor4l:ipdgaa, wilta 331 illimtraliona. Clotb, (3 ». (Joji AMi]*.
iibrih* anarli
TbI**'
■.p.r
lalanli
ptrt. IB a plala ..a .oa.l.a i»
ul 1 la AuafXaa adiur lih b»
tad IB
..al»i.
MOTlauoa* uf Iha lia-t aodt* DI ;
totftt
sihtria
■punaoea. rbabookdaHiia**
Ma
ip«n
u^aind
iiudtr lb* nioil laTsrabla ><K
■•(a
Utvniuiair, UuaxosiH abd TitHiTHRXT of tti IIla
■RICK TNETE9, t'.H.C.tt. Ki<g., ABaimani Suc^eoti
■t the Loniluii HoaiiiUU CuuiiileUi in
I'Hae, 10 MUU.
HntBT 0. Lka'8 Son a Co. 'a PtrBUOATion — (Surgmf).
fJOLMES [TIMOTHY). M.A..
A SYSTEM OF SURGERY; THEORKTtCAL AND PRACTICAL.
Is TsaiTiics BT riRiDBi 4iiTaaKi. Ahkiiciii BnixoK. TvoNocaai-r ■¥>»■» jura
at-KBiTBD bv JoBii U lUcEjuiD, M.D.. fiiirBaoa lo thr EpiHotwl Bad St. Juaph't Hooi.
tBl*. Pbiladattihii, («isUd bj ■ larf* carps nf tb* msM emineBt Amnieui ■argcoBI, la
tbiMlargt sDd IF17 b>Dj>a»* iiDfwtial oct»<i •olanrieonMlBiBp 31 >T gonfela-eiibinisad
c*g**. «ilbW9 illailr>lioDtoo*iiod«ad thinMDlitb<.gnphiepUtrt. bMHlifalljMlanfl.
Fri» pat Tnlnna. slotb. es OOi laMlnr. •? Mi bait RnuU, $T SO. For lat. elolk,
$18 to ; tMthar. (11 et 1 b>rr Huhib, It! »0. tStU tnlg ig i^tirnfH'»ii.)
Tdldhb I. (neiD rtoi/y) onnUina Qikekii. PiTMOLoar, HoMmiD PbockhHI. lunUBi la
Oa.iiKiiL. CaarLiojkTiona or iMcaiti lan Inji^aix* or Kaiiiaio.
ToLCHi tl. (msw rnu'ji) MBlaiai Diibabei or Dhsaks or Sfecial Sbjib, Oiacoi.«T0»T
SlSTBB. DlBBlTITB TbaCT AID ObRITO-DRIIABI ObOA».
VoLFKB lit. Ijiut rfadfi eoauini DitBAiBi or tbb RiiFtBAToar OaaAxi. Borbi. Joim
AID MoBC(.BS. DiiBARiia Or THB Mbhtoo Stitbh, Odhkhot Wodmhb, Opbbxiti AKO
MiiDB SuHaar. ash Ui>cai.LABCon» Si'ijbcts {including ad ttatj as QoiriiAU).
Thii gnat work, IfiDed loma ;BAn iln«a Ib BDglanit. h*> <ti>B asoh aai'^raal eauftdaboa
w1i(r*T<r tha l>Beiin|c* in ipokcn, tbat iu ripnblieilioD heia. in ■ (nru man IbtXDUflilj
adBpUd IS Iha wantt of Ifa* Anerieaa pntotiiionar, hai (eemed to ba ■ dnlj tiaiBS to lb* pr«-
To
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•opliib lfa<«,
ba Bid h» bo'D
iBTiOd of
Df
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aolrj.And
tl|H>n
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plaatd in
Utr^
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BO
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hotoogblj
to iba pr
ka*r
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Iba
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Kd witb
1.IT of .b. .mplo
I ..r albcr
and ehior
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>d of thir(7-(hroa of lb* noat i
lAtlDKotihed gantl*-
,!(iduaBfl7 an|*^d
ipceiallj (rBn|>tl«Bt
of tba
Ii
la Ahsorbanl SjiUm, wbora Iba vUw> of
iOBB and 8. C. ButaiL ctipcailral;^' Bo
icricBD ptaotiuo dilara'lrom tbat of Kng-
F Mtaj bj J. C. Kkitk. M.D., i»Attng
. hnl of lh« otfa»r >DBa<b*lie Acaau uf
■ijBti ravJiloD bai baon putPDed tbrongb-
:»B(, I'Adins (o la Increuc of DoaH; ont fuarth in matlir. whila lb* aarioa of illutritlBu. hiA
bMB naarly mblcd. and Ifae vhoU it praioniod at a complrlo cipsannt of firltiab aad AiBati-
•AB SarfTTj, AdHptad lo Iba d»ily oaedn "f iba working pruBiUianvr
tk* oricioal haia bran camprvoed iBM ihrfa, bjOBiplDjing a doanlo-mlmnBad Imparial osUto
■ua, ABd in ibia improved form it is off*r«d al [r*f tfaan oaa half tba prioo of Iba ongiaal It
fa (■Faatifullj' priotail on baDdir.ioa laid paper and toimi a wortbj oowpaBiou Iu Kktaulda'
SiraTiB or Midiciie, wbicli baa uat iritb >o moab faiar in artrj AaeUoB ol iba ooHntrj.
Tbo work vill ba lold bj inbAoriplion odI;, and in dua (ims tyttj uaaibor ol tha proholon
Will be oallad npoD lOd offir«d bd opfurtnnltj tt '"' "■""
IUaaMaeoipDrA11q>.l1rK«BtlTAe- |.
[■(■d<>;eT.Aa»,<.l>ooMIi>T(iMeB |
■H"''*
lUallarsa.tliaraiilli. ,
■rAciaiUad >a> toaici- i
i01L-(,K.». JoB«.. ./,,
It
H SmlLbadltiooarv'
MllMiao. 1
a* aot to laq
i.ll>)»r>-««l. anU n-rg.
vork (01 lb* Imvtcaa >dl-
w lr>i pabliwiKB. b?i ("o
tar.AUoa.lAprH'laawblik
•araai/. ■■« dliilBfiii.h II
adIB of .BTgHAl kaoirt^a.
■■■ itaT»oWt'_Br"la~Bi' mi' '^ " "" '"' f*". »"»■
£fH0JTT(KOBKHr), M.K.C.ii..^ "
THE PRlNClPLEa AND PRACTICE OF MODERN SURQERY.
A newandroTiAodAmorioAn. from tha EigbthonlatgedandimproTad London Bdilion, IUba-
(ratad with foar hundred and Iblrtj-Cva wood eDgrarlngi In oaa tbtj haBdioma oetBs
rolamo, of aaarlj TOO largaaad eloaal^ printed pagai. Cloth, $4 00 ; leathor, $6 00.
HBNRr C. Lba's Son & Co.'e Publications — (Surgery).
THE PKACTICE OF StTRQEBT. Third American. fromthpThird^
■nd REvi9«il BagKib Edilloil. Tfaaronghlj- rerited and math Imprnnil, b; /obn
Roberta, A.M., M.D. In noa lirgt and Tsry handiomr Imperial oou»o volttni* at
I litis pagaa. irilh T35 illnttralionB. Cloth, tS SO i iettbtr, SI iO ; leij bindfom* half
Rniala. railed banda, tS 00.
. 11 It <ll*i1»ilr II
roily™
I
.»Md Iha '
iiw Diati^rtd uoi (oBPd tn [ha Kngllili ■
la liu wrIltaD, too. -lib gtm efluelHBa», *kl^|
>. > r.ra Tlr<». I. .a In.rlua Htl-ratta SaglbH
iffiKciX fliepnl. U>F(b S, ISH.
nadaiK aad piaitlllasfra. tttilia buI prnlln, ii
darnUBdlng at mrileil prlBslplai >nd Iha Irtni-
JjJHICaSEN (JOBS B.). FES.. FR.CS.
THE SCIENCE AND ART OF SUKGERr; being a Treatise on Sn^
glcal lojuriti, DUeaecc aad OperationB. OararDll; raviaed by the AuCbar from t)w ^
Savaalband anlargad Ktigliab Udlllun. Ii two large and baaalifDl octavo (Otuaei of
neurly Suno pa,;«r, illnitratad b; elg-bt bnndrad and fIkI; two aagraiiiigB ob wood.
Clotb, (S SO ; lentbar. SIO SO; half Hniiia. raiiad bandi. (11 60.
iltbacBUKOtdiu*
«D. Hiii)»>lhita>d,<
[di-uidbobU«>, M«
IVHtcMnlMlaxparifB
alh^blsi
ET"
' a BiBdal Wll-buatl. WliiBvan
/hllrBMli' "l
■ Mrd.and Svra.Scyuritr.t
ibapMr* i gr«i ImpraTemaDt bat
luiiliaslrailnni. >>D<sbUDdrMluid fldj
liawn Tbaauthur blgbi^ (pfnclate* Ibi
iletabli irarkbMbatnrMaitMl by Annrl.
ibnaeTCTKoTUvonbaiiapprDtBl. TIiki
OD. Wtbni^liiHOBoiandtha'bwIi t!
il praellllciDanfi
■aim* laMrdapai
flOLUES (T2M0TiJT).M.A..
STJKGERY, ITS PRINCIPLES AND PRACTICE. ]
■omaoDUiToTolamaDf VRSpagBs. «lCb4II Ulnstratiaai. Clotb, tO;
Raatia, fT ftO.
Tl>abla. It will a.
IlllI^
tl*^ aUb* AUMtks MM
Henet C. Lea's So» Si ('o.'s FusLicAnoNS — yOphihalmology^etc.). 99
a/ELLS ( J. SOELDBHG). F.B.C.S.
A TREATISE ON DISEASES OF THE EYE. Third American,
rnimtbcTbird London Edition. IboroDEhl.v reviPFi]. wiltaeDpIoos ndditiriD*. bj Chiirtii
S. BiilJ,M.U.,6grg»u and Pathologitt to lb* Nev Yoik E;a und Ear InBrmnrj. tn
one I urge and ver<r baDdtiiDi* oi^taio TDlani< ot «tl» pngfi, wjih IM iLlu>lrHtii.Da on
wuod. Eii colored plsLei, nod aelectiona rrnm the T»t-1jpe> of Jaeger >nd SnellCD.
ClDtlj, $i i lenlber, $6 i half KusiU. raised bands, «6 fiO.
The inerllo of WaU>> Iteallie on dl>euei ul lli* i p»r»iitiiir» tlie beit tteallte of lltklDd la Ikelaa-
(alloB. Vary Utile ikBt )• praellcallT atetui lu ra- iaufferad 10 die.aoit *a an plaMad lu rKidie I]
cent a|>hlba<iDlchrera>nre Imri exwpad Ike edUoi. | (bird DdUlsa frun ibe liAadaoCllr. Bull. Siclal
Itmet. A>>l*Mt-liiiulio„opLlb>liuletar«e>7Airlba.[loat braoketau Willi bl< MlM Utlitj. Da^er
The wurlt iMJaiilf beldi liigh place In Kogliab '^'''''"'' "• a.efnlaOM.—JIf. y. <«!. Jukiti., Jaa
XTETTLESHiP {EDWARD), F.R.C.S.,
J-T OjyMftil»HeS.rp.a«di-«.o>i Uplift. S«rp.n( SI
»niM' SMpMat. Anndon.
THE STUDENT'd GUIDE TO DISEASES OF THE EYE. New
KdltlDD. WithaChapIer an the Detection ot Colnr-Bllndeesa, by WiLUAV XnoMBON,
U D., Opbtbalmolugitl lo tbe Jeffeimn Mcdienl Caltege. Id one rojal lima vol. of
about iOD pugei, nitb 13tl illuatmtiDiig. (/n a ftie dofi .)
!• snir •dlliDD or an ainllBDl h«Bilbc»ik oinbo- 1 riailaiiorbiLTliii Ihiir/liiRif irpbydcal ptlaoiplai
"■ ■ at band li mantlew. We cuaddenllr
BDlpltl
I oplloi to
be ballad
rtARTEK [R. BRUDENELL), F.R.C.S.,
^ Oi.hVial'mic ISuro-.onlK SI. Oiarei HI<M^Wil.Ue.
f>RO\YNE [EDOAK A.).
■i~* Burgfon in thl LItrrpilut Kyi and Ear Injlriililrlf.andla tint
HOW TO USE THE OPHTHALMOSCUPE.
Btrnetiam iiiOpbthalnioaflop^.arrBDtE'
tajalltmo., of tIB pagei. with 3& illi
JPSMARCH [Dr. FRIEDRICli).
JCJ i;.,/,.,.it bJ H^rg:-t al lA. ilHiwtls/itr Stl, irie.
EARLY AID IN INJUHlKd AND ACCIDENTS.
Bciug Eloroentary In-
Ibe Oer af Studeala. In one imall rolDme,
ioui. Cloth, tl.
Atnbuliince
Le«tutea. Iranilaled by U. K. li. Frucciis CBniiiri>». Id one bandioma (olame,
imall 12100. of mv paget, witb 2t illBitratlDD*. Ctuth. lb oenta. {Juil Ktaily.)
Tbfl llr.l. 01 lalrodMIurjr leuara. glT-i a briar 1 drowatag, af •aSauiloa, o( Iom of e<>B<>cloBiue"
BsmiuBl <ir tbe i>((ai!iflft aa* arfailHtloa of 1 be I and of putivBlii«*r*d*torll>id; and tbeflfth lamnia
hBBiJin bodjr, illailtated by clear, inllaliU dia- 1 (eavbei b.iv lujured Ntuan mtf be uval •atalT
(mia: Tie •eoaDl taaebee Baw ta iItb Jadleloai and gatll^r Iraanpiirlidla their liumag, la auadlul
al|i la wd lour la] urita — eoMii'taBe. »neDd<i, { inan er 1 1 abO'plial. Tbe UlmiiiaiiuiiilB tbtbuuK
■ - _...-i. . ..... .•■...1,^. _._ ..... n^j g^^^ n^^ imljl. weduiibi Dut, etm-
-JWrtienl TtuM
f
30 Henky 0. Lia'b Son St, Co.'b Fublioatiohb — (Olol,Metl.jHriB.'),
^/IhrlnJtT.fnrlMi vf tStSar.PUIa.
THK EAR. ITS ANATOMV. PHYSIOLOGY AND DISEASES.
APruLical Triittiae r<>r lb* Caa of Htdlosl ElndCDU and PrietilioBcri. iDonehsod-
somi ootiiro TOlun* or flIS p>gB>. *ith •)ft)it]r-ia**o lllaitratlan*: Otolh, I* Mi
Uklhvr. %b fin i t*r J handinmi: httif RuiKJn. railed bngdi, fS DB.
On.oegiiBlorih»((l«i»d.»B«-wlilft^h»..l«.B lb. bRBd> of ».rr n.illul .lagtfl.ta* lU .lodr
nxtiiof ).■• j»«r.rii uMogj, niKl gf ih* LuocuiHl will ».ll Mp»j Fli. fco.^ prMiliioB.r i» ih. pi».Mirj
ftOtlTZEi;
■*■ tmpfia'- Hi,
molt of
— SAnikriit Jr<d. Jnr., in^
A TEXT-BOOK OF Tlli^ KAK, ASD ITS DISEASES. Translated
>t the Autbar'i nqocd, by JiKii pATTiiuwir Cii*s>Lt.s, M.D.. F.F.P.B. In on* baa ~
toma uoMTO volam* of 3011 ragM, wtlh ZST lUailratlnD*. Cloth, tS btl. l,Jva Rea4i
Tlia Sim* nr l>r. ISiliiiBr In iDdioolBUfj xuki- Thtn tulldw. ■ dlavgiiliia t1 ihi rii.n.
lad Willi Ilia pmiraat of aanl toigorji iluilai ibl> atifril p,>rlli>ii< nt ilia nr«>a, Iha luldt . . ..
■■anuau. TBa 1« ll« -hteh »a ii,i. •illlai. "B Bi..i«ld pr^fMMlia lolifoul a.t, .la. lalacla.'.,
b1>b(aa>b k** long bwa. .UBJatd la OatinaBT. Iba "r«.a apd iha nUI1°n> nf air d lota aa in lin
oaj Bf Ihe aar Bad Ibe pb7.1o;o)
.,r af .Bdllloi
:tI1Ibi
/•A i'LOR [ALFRED S.),M.1>.
M. UelnriT an JfHi. /xHifi. nnrf irAmfMrv <n Oh»'« ffiupUal.
A MANUAL OF MEDICAL JURISPRUDENCE. EigliLli Ameri
son rrom tbe Tantb London Kdllion, tboroughij revind and lawrlltan. Bdiird bf JoBl
J HKEBB,H.D..PrcfBMar bf Msdijnl Jutliprudcues unil Toiieolugj rn Iba UiiiT*r*ily>
af PFnoBjlTaiiia. In oca larRe tetavo vnlsiua ol 937 psgsB, vilh 10 IlloalratloB*.-
Clntb. tSi IcHlber, SSi half Riutik, raitad band). (A to. {Ltlrt^ liiMtd.i
Tba A
tt«a bai NoaialHd iMacUlu villi fin
T^la osa, tba elMMb, >on» haiuia at a:
d«il7 B>
?:'". jT"
PKUDENCH. Ibltd Kdttion. In two bandtPiaa DtbtTO laluiuai. (U Fr-a.,
JlJ THE SAME AOTHVR.
POISONS IN RELATION TO MEDICAL JUBISPHUDENCB AND
MEDICINB. Third ALacricnn, fram the Third and Kevi^d Bngliab Itdilioi
largt octaTo Tolnma el TSd pagu. Cloth. «5 BU : Irathar. ft 60.
Bl.,,., ..,,.1^
llB<ulacl..BaM»B^
J IBO BOB • ■■tHIBBtal
midl«»-la(Blt«UBgB} (asd wbal aaU auDJ.c
r'fDF(CHARLES MEYMOTT). MB.. F.C.S . .
Prii/iM'irn/CStmittrv't'.da/ Purtnuc MtdieimaHd PutUc BraH\ at llu Lonitm UttpOalttU,
LEGAL MEDICINE. Volume I, Embrnciiig Evihejice. Tub Siodi
UiKMAPuiuiDiaK, KiracTATioiior Lira. Prrb
Haar Ann Ocn, Bi'Hav, Liodthihs, Eiplusivki,
■nna Impeilal ostaru ruluina utMi pagai, with i fa'
luther, S?. (.^Ht StoJtii.i
Utwhoar ladlaBilauBUF ariouiloa Uad blai lo "
a..iii» Iba rBaelluaa Bf • i.i.ai(al Jarl.l. w.Bl. b
b.".ll .aerrlnp-dl. 1« tb.racl.r. t,: wl.,.b b. niay ha
raBMBibir nara of nadtnc ni(rtiuwl»i{.i loplc. di>-
c»Md wflb JadliUl UUuta. wiili .uflelam con
ri. Xhb PasT-Hui
ilirull; oolorsd pUUi. Ololh, t* i
« t.ry anniaiuaB IUa>lrall>a «••• Bi«di««B
a ■ddliloaVl f.« Ibal ibaVira b'aH^4rn-a
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<.aTarX"btlaD<r>atna-b<i>fe>i«<>li(alai
Henbt G. Lba'b Son Sl Co.'8 Publioations — iMtscellaneovs), 81
TfO BERTS ( WILLIAM), M,D.,
•^ V Leciurftr on M^jdicinti in th*. MancKtster School o/ Medicine, «te.
A PRACTICAL TREATISE ON URINARY AND RENAL Dlfi-
EASES, iDcIading Urinary Deposits. lUostrated by nnmeroiis oases and engravings.
Fourth Aiuericun, from the Fourth Revised and Enlarged London Edition. In one
large and handsome octavo volnme* (Freparing.)
ffHOMFi^ON (SIR HENRY),
•* Hnrifun nnd Pm/eMftor of Clinical fhnrgery to Univeritlty ColUgt. Hospital .
LECTURES ON DISEASES OF THE URINARY ORGANS. With
illu&trntions on wood. Second American from the Third English Edition. In one
octavo rulnme of 203 pages, with 25 iUu8tratious. Cloth, $2 25.
oy THE SAME AUTHOR. ■
ON THE PATHOLOGY AND TRE ATiMENT OF STRICTURE OF
THE URETHRA AND URINARY FISTULiE. With plates and wood-cntit. From the
Third and revised English Edition. In one very handsome octavo volume. Cloth, $3 6<*.
BASHAM ON RENAL DISEASED: AGiiaieal Qntde LBCTUKEti ON THE STUDT OP FEVEK. By A.
to Ttirtir OiAituoHiii <iud TrfiAtmMDi. Inon«l2mo. ' Htdso.n, M.D.. .M.K.I. A.. PhyHici.t.a (o th« Meath
Tol o(S(Uiuti;eH,witb illaHtraiioDK. Clo»h,iy 00. ! Ho-tpitai. lu on^ vol. 8to. Cloth, fi •'^0.
A TREATISE ON FEVER. By Kobkkt D. LroF^j STOKES* LECPOUES ON FEVER. Ediiod by John
K.CO. la oae octavo volame of •'<tJ2 piiges. \VliliiiiirM.,ore, .M.D., F. K.Q OP. InonbOutaTo
Cl>t^.«22.^. I Tolame of 264 pHg***. Clolh, $2 00.
fPUKE {DANIEL HACKu Ml).,
^ Ji'int fiKthor 'if Thf. Xanualof P.tgvkologieal Medicine, Ac.
ILLUSTRATIONS OF THE INFLUENCE OF THE MIND UPON
THE BODY IN HEALTH AND DISEASE. Designed to illustrate the Action of the
Imagination. New Edition In one hftnd«ome ootavo volume {Prrptirittg.)
DLANDFORD (G, FIELDING), M,D., F.R.C.P,,
^ Jf-vturer on Fsyvkological M*idicine at tkf. S'^honl »/ St. George*^ HotpUn.1^ Ac.
INSAXITV AND ITS TREATMENT: Lccliuea on the Treatment,
Medical and Legal, of Insane Patients. With a Summary of the Lnws in force in the
United States on the Confinement of the Insane. By Isaac Ray, M.D. In one very
hand.some octavo volume of 471 pages.
r EA {HENRY C),
SUi^ERiSTITION AND FORCE: ESSAYS ON TEIE WAOER OF
LAW, THE WAUEK OF BATTLE, THE ORDEAL AND TORTURE. Third Revised
and Enlarged Edition, [n one hand!*ome royal 12mo. volume of 652 pages. Oloth,
$2 50. {Lately Issued.)
Thli valuable work U in reality a hi^ttory of eivl- | more Hccnr.ite tbao either of (h« preeeding, but,
hxktiou Hb luterprflted by ihe pr«greii« of jDrUprU'i froia the thorough eUbor.ition in more like a har-
d«oee. ... lu '*Sap«iMittiou «ud Por<:«" we have i mouloan e'>aceri aud lenii like a t>alch of Hiadio.^
a pbilo««>phic HiirTey of tb«i luu^ p«rl«>d iaterTcniug I Thf AVr/r»n, A'lg 1, 1878.
baiween priinliWe barb.iriiy and clflllied enilghl-1 ^^^j ^jn be tempted to nay that this, like the
eaiueoi. i'htire li not a chapter in the work that
«nonld not be uioMt c<irefnlly etadied, and h«»wever
DecliuoaudF«tll."iNuueof iheuncritloisabte book«
IlB faciHaieinnaraerable.itii dedoctlon)**impl#aDd
The Appearanoe ol a new edition or Mr. Henry G. I polemic. Though he oovlunely f^eU and thlnki
Lea'ii ".^uperntltion and Force" ie a e.gn that oar | ntrnagiy, he ancceedH In attniulng iinp»rtlalltT.
biglieMiicljMlarrhip lb not wltboat honor In Ite n«i '. \Vlieiier looked nn a* a plrinr« ur » mirror, a work
ilvecuuutry. Mr. Lea hae met every frenh demand r>ach ha thU baf » Irf-stlag VHiae. — Lippincott'n
for hie work with a earefol rerWlon of It, and the ' Magaziat-^ Oct. I S7S.
pretent ecitton te not only fuller »ad,lf poiiitlble, !
Jjr THE SAMK AUTHOR.
STUDIES IN CHURCH HISTORY. THE RISE OF THE TEM-
PORAL POWER— BENEFIT OF CLEROT— EXCOMMUNICATION. New Edition.
In one very handnome royal octavo volame of about 50U pagef . {In a few day$,)
A few notices of the previoai edition are appended.
Tae story wae never told moreealmlyor with, i»i a peculiar ImporiancefortheBaglUhetadeat^Bd
greater learning or wleer thought. Weduabt,ladeed,i le a chapter on Ancient Law Likely lobe regarded at
ifany other»tudy ofthlK Aeldcanbeeompared with' ftnal. Wecaa hardly pa ■» from oar mention ofanch
thU for clearnetie, .iccaraey, and power. — (/Moap'O ' work** a» tbeee— with which that on "Sacerdotal
/7ramfn<»r, Dee. 1870. Oellb»ev'' «hoald be Included —wltbAit noting the
literary pheaomeaon thai the head of one of the flret
American hoaiie«Ualiio the writer of flomeofltenoni
Mr. Lea's lateat work,'* StadlealnOhoreh Hietory,'*
rillysaxtalnethepromUeof theflrat. Itdeala with
three sabjectn— the Temporal Power, Benefit of!<»'Uln*l heoke.— Lonrfon 4/*4tiMr«»i. Jaa.7,1871
Clergy and fizcommanlcatloa. the record of wfalehl
Hbmrt 0. LsA*B Son A Oo.'s Pvblioatioks.
IKDKX TO CATALOGUE.
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