Chemical Reagent Their Purity and Tests

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C H E M I C A L R E A G E N T S

T H E I R P U R I T Y A N D T E S T S

A NEW AND IMPROVED TEXT

BASED ON AND REPLACING THE LATEST EDITION OF

K R A U C H

' DIE PRUFUNG DER CHEMISCHEN REAGENTIEN AUF REINHEIT'

BY

E . M E R C K





DR.

As long ago as the ear ly sevent ies 1 fel l , (ho need of a

t rea t ise on Chem ica l Reagents , and tho ug ht o f co m pi l ing

suc h a. w o rk . I was I hen an assistant in Mir ch em ica l

l ab o r a t o r y o f t he ( Jove rnm en t A g r i cu l t u r a l Kx po r im e n t

Sta t ion a t . M in is te r , and in my chemica l work (here met w i th



T R A N S L A T O R ' S P M W A C I C

Tin-; desire of Am erican chem ists (o r id themse lves of the

m is l e a d ing IITIII4 4

C . 1 \ ,M an d tof>;et in its ste ad definite st a te -

m en ts as to the exact d(igr( v(v of pur ify of their reagents or

( he exact i iinil . of the im pu rit ies , impelled the Am ericanC he m ic al S o ci et y , in l!)0L\ to cr ea te a. C\itmiiit.(.<k<^ on Pu ri t y

of Rea; j;eu( s. In l!M)C> I h i s C om m i t t e e a dv ise d a ga ins t t he



articles wliich arc universally used here \nit tin mil n ' m f««

so in Eu rop e, and for which sperificiitinn . m u ld In* inm

in au th or ita tiv e Am erican publication.-». Tlu-v w v <lhiri

Acetic Acid M)J)%, M% A rct ic Ariil . HytIi««'hlMn.- \«-t.|

a specific g ra v ity of l.O.K), N it ric Arid u ifh «<n«- »»! I J

Phosphoric Acid with one of U)/>7, UV S u l p h u n r \ r j .

2(S% Ainnionia Water, 9a (y ( Aln ilutl, uu»l U lv r n u j nt H I ::»

specific gravity. friuk slight <'hni»^tv* ul»viuu-ilv iit*n-'< :i r\

th e te x t on ac cou nt of the se ad di tio ns lm\»* h*'»*n r ;ut* lni

m ad e .



T R A N S L A T O R S N O T E

F O R the sake o f b rev i ty , express ions th roughout the book

ar e som etim es used w ith ou t ful l qual if ication. Th e fol low-

ing i s then to be the i r in te rpre ta t ion .Atomic Weights , Quanti ta t ive Calulat ions , e tc . , are based

on t he ta b le o f In t e rn a t io na l Atom ic W eigh ts for 1906



C H E M I C A L R E A G E N T S

ACETONE

(CH3)sCO. Mol. Wt. 58.04.

A clear, colorless liquid, boiling a t 56 to 57° C , wit h a

specific gravity of 0.797.

TESTS OF PURITY



2 CHEMICAL REAGENTS

A C I D A C E T I C

HC2H3O2. Mol. Wt. 60.03.

I

ACID ACETIC, 99.5%

A clear, colorless liquid, with a strong odor; miscible in a



CHEMICAL REAGENTS 3

Substances Reducing Permanganate. — 2 co. of th e acid

arc di luted with 10 co. of w ater , and 0.1 ec . of dec ino nn al

solu t ion of potass ium permangana te added. The p ink

color shou ld no t be en t ire l y changed to brow n w ithin two

hours .

Other Empyreumatic Bodies. — No sm oky odor should be

noticeable upon m akin g 10 cc . of the acid a lkal ine wi th solu-

t ion of potass ium hydroxide .

Quanti ta t ive Determinat ions. — Dilute 10 gm. of acet ic acid

with sufl ic ient wa ter to m ak e 100 cc . T i tr a te 10 cc . of thi s

solu t ion wi th norm al potass ium hyd roxide solu t ion , us ing

phenolphtha le in as the indica tor .



4 CHEMICAL REAGENTS

of dec inormal po tass ium permangana te so lu t ion to a mix turof 5 cc. of acetic acid with 15 cc. of water, the red colo

should not disappear within f i f teen minutes .

I l l

ACID ACETIC, 90%



CllEAflCAL REAGENTS 5

(ACID) ACETIC ANHYDRIDE

((!lI:,.C())a( ) . Mol. Wt, 102.05.

A colorless liquid of pungent odor, boiling at 137° C.

Specif ic gravity 1 .OS.

On pour ing acet ic anhydr ide in to water , i t does not a t

f irs t mix with the latter , but s inks to the bottom of the

vessel. G radu ally , how eve r, i t dissolves, forming ace tic acid .

TICSTS OF PURITY

Hydrochloric Acid. — 1 cc. of acetic anh ydr id e d i lu ted with50 cc. of wa ter , and acid ula ted w ith 5 cc. of nitr ic acid, shou ld

give no react ion with s i lver n i t ra te solut ion.



0 CHEMICAL HKMiKXTS

chloric ac id * to «> gin. of ( he pow dered boric au hy

weighed plat inu m dish, s l i r with a pla t inu m wire

pletely dissolved, and ev ap ora te the liquid over a sm

th e pl at in um dish l>c»ing place d on wire ga uz e. If

rema ins, i t is treate d ane w w ith 2f> ee. of the m eth yhydrochlor ic acid, the l iquid evaporated, nnd the

cond uits gent ly igni ted. There must remain no

res idue.

AC ID CARM1N1C f

Purp le-brow n, am orp ho us masses , af fording a powder on t r i tu rat i on . Carminie acid is eas i ly

wa ter and in alcoho l, hut is insoluble in benz ene a



CHEMICAL REAGENTS

If the carminic acid is intended to be used as an indicatin acidimetry, i t must f irst be tested as to i ts sensi t ivenes

as follows:

Dissolve 1 gm . of th e carm inic acid in 100 cc. of w at

and add one drop of this solution to a solution of 5 gm. am m on iu m chloride in 50 cc. of w ater. T he ad dit io n to th



8 CHEMICAL REAGENTS

not be r endered turb id by the addi t ion of ba r ium

solut ion.

Calcium. — 20 cc . of the 1:10 aque ous solut ion m u s t

be r endered turb id by the addi t ion of am mo nium

solut ion.

Lead.* — A solut ion of 5 gm. of c it r ic acid in 10 c c .

water , to which 12 cc . of ammonia water are added,

not acqui r e a da rk co lor upon adding f r esh ly made , s a tur£

hydrogen su lphide wate r .

Non-vola ti le Mat te r . — 1 gm. of c i t r ic ac id mu s t l e a v e

weighable res idue on igni t ion.

Quant ita tive Dete rmina t ion . — On d isso lv ing 1 gm. of c i t

ac id in 30 cc. of wa te r and t i t r a t ing w i th n ormal p o t a s s r

hyd r ox ide s o lu t ion , u s ing phe no lph thal e in a s i nd i c a to r ,



CHEMICAL REAGENTS 9

to constant weight , i t should not lose more than 0.1 gm. in

we igh t .

Sulphuric Acid. — On add ing 1 cc. of hy droch loric acid

an d some bariu m chloride solution to a 1:50 aqu eou s solu-t ion of gall ic acid, a precipitate of bar ium sulphate must not

form wi th in an hour .

Inorganic Matter. — 1 gm. of gallic acid must leave no

weighable residue on ignit ion.

A C I D H Y D R I O D I C

HI. Mol. Wt. 127.97.



10 -CHEMICAL REAGENTS

Hydrochloric and Hydrobromic Acids. — D i lute 1 gm.

hydriodic acid with 20 cc. of water, add an excess of silv

nitra te solution followed by 30 cc . of ammonia water, sha

well, and filter. On aci du lati ng th e filtrate w ith nit ric ac

only a s l igh t tu rb id i ty may deve lop , never a p rec ip i ta te .*

Quantitative Determination. — Dilute 5 gm. of hyd riod

acid with 50 cc . of water and t i tra te with normal potass iu

hydro xide so lu t ion , us ing m ethy l o range as ind ica tor .

leas t 17 cc . of the normal a lkali solution must be required

effect the change in color.

1 cc . of normal KOH = 0.12797 gm. of H I, log. 10710.



CHEMICAL REAGENTS 11

evapora t ion on the wate r-ba th should leave no weighable

res idue .

Sulphuric Acid. — On d i lut ing 5 gm. of hy dr ob ro m ic acid

with f ) ( ) ce . of water and adding barium chloride solut ion, aprec ip i ta te of bar ium sulpha te should not form on s tanding

twelve hours .

Heavy Metals . —

(a ) Dilute 10 gin. of hydrobromic acid with 10 cc. of

wate r and over lay wi th hydrogen sulphide wate r ;

nei ther a colorat ion nor a yel low ring should format the contact-surfaces of the two l iquids on standing

one hour .



12 CHEMICAL /i7;.U,7vVV',S

Besides the above test for hydriodie acid,

may also be employed:

On a d d in g I dr op of ferric chlo ride so luti on

hy dr ob ro m ie acid , an d shakin*;; with f> ee . (»f chllat ter sho uld not acq uire a. violet color.

Ph osp ho rou s and Pho spho ric Acids. U ra l 1 j»

bromic. acid willi I cc. of nitric acid to boiling, a

and then ad d I ec. of am m on ia wate r followed

magnes ium sulph ate solut ion. No prec ipi ta te

oven on s tanding two hours ,Qu ant itativ e Determ ixiation. Dilute f> <,mi. of

acid with f>0 cr . of water , and t i t ra te with norm




Chlorin e.* — D ilu te 5 gm . of hydroch loric acid w ith 50 cc.

of wa ter and add zinc iodide-s tarch solut ion. Th e l iquid

must not develop a blue color within ten minutes .

Sulph urous Acid. — 50 cc. of w ater are colored blue by th e

addition of 1 drop of decinormal iodine solution and a few

drop s of s tarch solut ion. The n add a m ixt ure conta ining

5 gm. of the hydrochloric acid to be tested and 50 cc. of

wa ter . Th e liquid m us t not be decolorized af ter being

sh ak en .

Heavy Metals . —

(a) Dilute 20 gm. of hydrochloric acid with 200 cc. of



]4 CUEM HWL lil' lAUK XTS

residue from the abo ve eva po rat ion is washed into th e

cra t ing flask of the app ar at us by the aid of di lu te sulp h

acid. After the api>ara( us has been in actio n for one hthere m ay be at m ost a w r y slight depo si t in the red uc

tub e bu t no dist inc t ly visible arsenic m irror .

Qu ant i tat ive D eterm inat ion. T he st re ng th of the

may be most s imply ascertained from the specif ic gravi t

On dilu tin g .'J gin, of hy dro ch loric acid w ith 50 ce, of wand t i t ra t ing wi th normal potass ium hydroxide so lu




I I I

ACID HYD ROC HLO RIC, SP. GR. 1.050

A clear, colorless liquid, of specific gravity about 1.050,

an d containin g abo ut 10 per cent of HC1.

TESTS OF PURITY

The tes ts to be made are those given under Fuming Hy-

droch loric Acid. Bu t, inste ad of using 10 gm . of th e fuming

acid, use 35 gm. of the 10 per cent acid.



16 CHEMICAL REAGENTS

alkaline reaction; on now adding ammonium phosphate sol

tion, no precipitate should form on standing three hours.

Hea vy Metals. —

(a) Dilute 10 gm. of hydrofluoric acid w ith 4 0 cc. of w ate

warm the l iquid, and saturate with hydrogen su

phide gas. Neither a yellow nor a dark-color

precipitate should form.

(b ) Dilute 5 gm. of hydrofluoric acid with 50 cc. of wat

make the solution alkaline with ammonia wate

and add am m onium sulphide solution. A gre

coloration must not develop, nor should a precipita




TESTS OF PURITY

Won-volati le M atter. — 5 gm. of hydrosilicofluoric acid ev ap -

orated in a plat inum dish should leave no weighable residue.He avy M etals. — Dilu te 5 g m . of hydrosilicofluoric acid

with 10 cc. of water, add a few drops of hydrochloric acid

and 10 cc. of hyd rogen sulphide wa ter . No vis ible change

should take p lace .

Su lphuric Acid. — On dilu ting 5 gm . of hydrosil icofluoric

acid with 10 cc. of water and adding a solution of barium-frees t ront ium ni t ra te , no prec ipi ta te should form, even on s tand-



18CHEMICAL IWAUUSTS

(ACID) IODIC ANHYDRIDE

(loi) IN K PlONTOX !!>!•:)

Uh. Mol. Wt. MUM I.

A white ; crystallines powder, sohihlr in wafer witformation of the hydrated acid, MO.,, but insoluble in

lute alcohol, ether, and carbon disulphide.

TKSTS OK PUHITY

The tests to be mad e are those given under bnlir A

1 cc. of decinormal Na2S,O,, <).()0fJ7S2S:j #'»• of

log. 44 48.ACID MOLYBDIC

II,M<>(>,. Mol. Wt. HW.OI.




TESTS OF PURITY

Alkalies. — On heatin g 1 gm . of molybdic anh ydri de in a

test tube, the par t icles adhering to the heated port ion begin

to fuse at a red heat, while at the upper, cooler portion of

the tube a crystal l ine formation of sublimed anhydride may

be observe d. I f the molybd ic anhyd ride is con tam inat ed

with salts of the alkalies, the whole melts to a dark-colored

ma ss . In such case the melt ing-point is low.

A mm oniu m Salts . — On boil ing 1 gm. of molybdic an hy -

dride with sodium hydroxide solution, there must be noliberat ion of ammonia ( to be ascer tained by means of moist-

ened l i tmus pape r ) .




dilute with 200 cc. of water, heat to boiling, then add asolution of 1.5 gm. crystallized lead acetate in 20 cc. of

w ater . Boil for several m inu tes with co ns tan t s t i rr ing

wh ereby the precipi tate, a t f irst m ilky, is ren dere d gr an ula

an d easy to filter. Collect th e pr ec ip ita te on a filter, p re

viously dried at 100° C. and weighed, and wash it with boiling




TESTS OF PURITY

Non-volatile Matter. — 4 cc. of ni t r ic acid on eva po rat ion

should leave no weighable residue.

Sulphuric Acid. — Dilute 4 cc. of nitric acid with 90 cc. ofwa ter, and ad d barium chloride solut ion. No pre cipi ta te of

bar ium sulpha te should form on s tanding twelve hours .

Hydrogen-Halogen Acids.—4 cc. of ni t r ic acid di luted with

90 cc . of water must not appear changed on the addit ion of

si lver ni t ra te solut ion.

Heavy Metals, and Earths. — Dilu te 8 cc. of nitr ic acidwith 80 cc . of water, and render s l ight ly a lkal ine with am-

mo nia wa ter. On adding a few drops of amm on ium sul-




I I I

ACID NIT RIC , SP . GR. 1.20

A clear, colorless liquid, of specific gravity 1.20, and

taining about 33 per cent of HN0 3 .

TESTS OF PURITY

Th e tests to be ma de are those given un de r Acid N

sp . gr. 1.40 ; observing the cond it ions there descr ibed.

in ste ad of 4 cc. of a cid sp. gr. 1.4 0, 10 cc. of acid sp

1.20 are to be used.

I V



CHEMICAL REAGENTS 2 3

TESTS OF PURITY

Th e tes ts to be m ade are those given und er Acid N it r ic

sp . gr. 1.40. B u t for 4 cc. of acid sp . gr. 1.40, use 5 c c. of

fuming ni t r ic acid .

ACID OXALIC

H2C2O4 + 2H2O. Mol. Wt. 126.04 .

Colorless, odorless, prismatic crystals, free from efflores-

cence. Cry stall ized oxalic acid is soluble in 10 pa rts of co ld,

and in a bo ut 3 pa rts of boi ling, water , in 2 .5 pa rts of alcohol ,

and in ab ou t 100 par t s of e ther . On heat ing the hyd ra te d

oxalic acid in a capillary tube, it liquefies at 98° C. in its




ammonia water to this l iquid unt i l a lkal ine, nei ther a

nor a brown colorat ion should develop, nor should a pr ec ip

form.Am monium Compounds. —

(a) The solution of 5 gm. of crystall ized oxalic ac

30 cc. of sodium hydroxide solut ion on being b

should not evolve ammonia ( to be ascer ta ine

means of mois tened l i tmus paper ) .

(6) On dissolving 2.5 gm. of oxalic acid and 5 gm

potass ium h ydro xide in 30 cc . of water , and ad




ACID OXALIC, SUBLIMED

H2G>04. Mol. W t. 90.01.

A white , crysta l l ine , exceedingly hygroscopic powder ,m el t ing a t 187° C. The prep ara t ion mu s t con ta in a t l eas t

99.5 per cent of anhydrous oxal ic acid , H 2C2O 4 .

TESTS OF PURITY

Ash. — 1 0 gm . of th e oxalic acid on ignition should lea ve

no weighable res idue .

Other Tests, — Th e other tes ts to be m ad e are those given



26 CHEMICAL HtiMiK NTS

of nitric acid should no t be rendered m ore than sl

turbid by silver nitrate solution.

Barium. — 10 cc. of perc hlor ic acid dilu ted w ith f>0

wa ter mu st not become turbid w ithin five m inute s on" a

dilute sulphuric acid.He avy M etals. 10 cc. of perchloric acid dilut ed

4 0 cc. of water must- show no change on ad din g hy d

sulphide wa ter; and on addin g to this solution 10 r

ammonia water, and a few drops of ammonium sul

solution, a precipitate should not form, nor should the

acquire a green or brown color.

ACID PHOSPHOMOLYBDIC




TESTS OF PURITY

Volatile Acids. — Mix 30 cc. of th e pho spho ric acid w ith

50 cc. of w at er in a distillin g flask. Distil * off 50 cc. ; an d

t i t ra te the d i s t i l l a t e wi th dec inormal potas s ium hydroxidesolu t ion, us ing m ethy l orange as indicator . No t more th an

0.1 cc . of the decinormal a lkal i solut ion should be required.

Nitric Acid. — 2 cc. of pho sph oric acid mixe d w ith 2 cc. of

co nc en trate d sulphuric acid, and overla id wi th 1 cc . of a

solut ion of ferrous sulphate , must not develop a colored zone.

Hydrogen-Halogen Acids and Phosphorous Acid. — 2 cc. of

phosphoric acid di luted with 18 cc . of water should give noreact ion with s i lver ni t ra te solut ion ei ther in the cold or on

w a r m i n g .




drops of decinormal potass ium permanganate solut ion

mixture of 5 cc. of phosphoric acid and 5 cc. of diluted

phuric acid, and then he at ing for five m inu tes a t 100the red color of the l iquid should not disappear.

Arsenic. — A Marsh a pp ara tus is s ta r te d using 20 gm

arsenic-free, granulated zinc, and di lu ted ( 1: 5 ) sulph

acid. A m ixture of 3 cc. of pho sph oric ac id with 20 c

water is then introduced in small quant i t ies at a t ime,

evolut ion of hydrogen being maintained for about two hA deposit of arsenic should not be visible in the redu




I I I

ACID PHOSPHORIC, SP. GR. 1.057

A clear, colorless, odorless l iquid of specific gravity about

1.057, and containing about 10 per cent of H 3PO 4 .

TESTS OF PURITY

The tes ts to be made are those given under Acid Phos-

ph ori c sp . gr . 1.7. B u t for 1 cc. of the acid sp . gr. 1.7,

use 10 cc. of the acid sp. gr. 1.057.

(ACID) PHOSPHORIC ANHYDRIDE



30 CUKMH'M' JtHMtK SrS

T10STS OK H'lUTY

Nitr ic Acid. --On adding 2 ee. of concentrated .sulphuric*

acid to a solution of I gm. of metaphosphoric acid in 2 cc .

of water , and overlaying the m ixtu re with 1 ee. of a solu tion

of ferrous sulphate , no colored zone should form.Sulphuric Acid. The solution of 1 gin. of m etap hos ph orie

acid in 20 cc. of water must, not immediately he rendered

tur bid on the addition of /> ee. of hydro chlo ric a cid, followed

by barium chloride solution.

Hydrogen-Halogen Acids. Add /> cc of nitric acid to u

solution of 1 gm . of mcra pho sph orie acid in 20 ee. of w ate r.

On the further addition of s i lver nitrate solution (he l iquid

should appear unchanged.




TESTS OF PURITY

Nitrates. — Dissolve 1 gm. of pho spho tung stic acid in 10 cc .

of water , ad d a granule of sodium chloride and 1 dro p of

indigo solution ( 1:1 00 0) , fol lowed by 10 cc . of co ncen trated

sulph uric acid. Th e blue color of the m ixtu re m us t no t

d isappear wi th in ten minutes .

A mm oni um Salts . — On h eatin g a solution of 1 gm. of

phosphotungstic acid in 10 cc . of water , with 5 cc . of sodium

hy dro xid e solution ( sp. gr . 1.3) , no am mo nia should be

evolved ( to be ascer ta ined by means of dampened l i tmus

p a p e r ) .NOTE. — Regarding a method for the quantitative analysis of phos-

photungstic acid, see F. Kehrmann, Ber., 20, 1813 (1887); J. Chem. Soc,



32 CHEMICAL REMiESTX

picric acid m ust com pletely dissolve in 20 <T. of be nz en

affording a clear solution.

Oxalic Acid. On ad din g calcium chloride solu tion to

solu tion of 1 gm . of picric acid in KM) re . of water, a precipita

of calcium oxalate should not form within two hours.

Free and Combined Sulphuric Acid. Kvnpornte a mix fun

of 2 gin. of picric acid an d 10 ec. of nitric aeid fsp. *y\ 1,-1

to dry nes s on the w ater -ba th. Dissolve the residu e in KM) e

of boiling water with the addition of 5 ce. of nitric aeid

allow to cool, then filter, and add barium nitrate solution t

the fi l trate. There should be no imm ediate t urb idit y.Inorganic Matter (A sh) . 1 gm . of picric aeid c au tiou s!

incinerated in an open platinum dish should not leave




ACID SUCCINIC

GiHeOi. Mol. Wt. 118.04.

Colorless, monoclinic prisms, soluble in 20 parts of cold

and a bo ut 2 pa r ts of boiling w ate r ; in 10 par ts of a lcoholand in 80 pa rt s of ethe r. Succinic acid me lts at 182° C ,

and at 235° C. it boils with the evolution of white acrid

fumes, while i t undergoes decomposit ion to a large extent

into water and succinic anhydride.

TESTS OF PURITY

Non-volatile Matter. — 1 gm. of succinic acid heated in a

pla t inu m dish should volat i lize an d leave no weighable



34 C UK M W AL H K A U K K T S

acid in 50 cc. of water, and titr ate w ith uon uu l po ta

hydroxide, using phenolphthalein us indicator .

1 cc . of normal KO H 0.05902 gm. of (\Iitt< >«, l<tf.

ACID SULPHANILIC

CoIMNHiOCrtOalOh.l ! 2H-.O. Mol. Wt.'JW .lK.

Sulphanilic acid occurs in colorless, neieulur, ef llo

crysta ls . I t has no melt ing-po int , hut carbonizes on

he ate d to 280 to 300° (.5. T he acid is dillic ultly su iu

cold wa ter ( abou t 150 pa rts ) , bu t more readily solub

hot water; it is insoluble in alcohol, ether, and benzene

TKSTS OK PI'HITV




TESTS OF PURITY

Non-volatile Matter. — 1 0 cc. of sulphu ric acid, on being

evaporated and igni ted, should leave no weighable residue.

Nitric Acid. — D i lu te 1 cc. of sulphuric acid with 9 cc. of

water, and overlay this l iquid on 5 cc . of diphenylamine

solut ion (see Diph enylam ine, page 100) . A blue zone should

not form at the contact-surfaces of the two l iquids.

Selenium. — On ove rlayin g 2 cc. of sulphu ric acid w ith

2 cc. of hydrochloric acid, in which a granule of sodium

sulphite has been dissolved, a reddish zone must not form at

the contact-surfaces of the two l iquids; nor should a redprec ip i ta te form on warming.



30 (UIK Mlt'Al, itlwUt'K STS

nor, after the passage of the gas, should any b

flocks precipitate on long standing (Tin).

Ammonium Salts. Dilute 2 ec. of sulphuric acid

30 c.c. of water, and add aq ue ou s solution of p ot as

hy dr ox id e (1:<>) to alk ali ni ty , followed by 10 In 1T> d ro

Ness ler's reage nt. At. most a. light-yellow pre ci pi tat e

form, but in no ease a brownish-red one.

Arsenic* — A Marsh ap pa rat us is se t in ope ration ,

20 gm. of arsenic-free, gr an ula ted zinc, and a rse nic

dilute sulphuric, acid ( 1 :5 ) . As soon as the air h as

expelled from the apparatus, heat the reduction tub

redness, and then introdu ce a cooled m ixtu re of 10 rth e acid ( sp. gr. l.K-l) to be tes ted a nd f>0 ee. of wa te r.

deposit of arsenic should be visible in the redu ction



CIIKMH1A L A'A'.-l aKNTS I*7

TKSTS OF PURITY

The tes ts to ho made a re those g iven under Acid Sulphur ic

fip. gr. L S I. Hut for I cc. of the ari d sp . gr. I ,S i use il rr .

of t h e ac id >sp. gr . I.I 10.

I l l

A C I D S U L P H U R I C , xo%

A colorless li( |uid of specific gravity about, 1.070, a n d

co nta ini ng ab ou t K) per cen t of II2S<) 4 .



3 8 CHEMICAL REAGENTS

A C I D S U L P H U R I C , F U M I N G

A C I D SULPHURIC, FUMING. FR EE FROM NITROG

A colorless, oily l iquid, fuming in the air , and contai

8 to 10 per cent of free SO 3 (i.e., 83.1 to 83.5 per cent

TESTS OF PURITY




dilute (1 :5 ) sulph uric acid. As soon as the air has been

expelled from the apparatus, heat the reduction tube to

redness, then run into the apparatus a cooled mixture of

10 cc. of the fuming sulphuric acid with 90 cc. of water.

No deposit of arsenic should be visible in the reduction tubewithin half an hour .

Quantitative Determination.* — Weigh off acc urate ly 1 gm .

of fuming su lphuric acid in a Lun ge-R ey stoppered bulb

pipette , t and cautiously al low the acid to run into 10 cc.

of w ater , con tained in a porcelain dish. The conte nts of

the dish are now r insed into a measuring f lask of 100 cc.

capacity , and the f lask then f i l led up with water to the

m ark . After vigoro usly shaking , 25 cc. of the liquid are



4 0 CU KM 1( M L RF.A (i US TS

8 to 10 per cent of free SO.,, and is inte nd ed for ni tro g

dotertninations by the Kjeldahl method.

TKSTS OK 1TIUTY

Nitrogen. Dilute li() ee. of the fuming sulphuric arid

a retort with 200 ee. of wafer, and when eold add nit rog efree solution of sodium hydroxide (sp. #r. l.. '{) , until .strong

alka line. The n add )> gin. of zinc du st, distil off a b o

50 co., and collect (he distil late in a I- tu b e receiver c o

tain ing ab ou t 10 co. of wa ter an d 2 to l\ oe. of fifth n or m

hydrochloric, acid. Th e dist illate is then titr ate d w ith fif

normal potassium hydroxide solution, u.sing methyl oran

as indicator . The amm onia should not have consum ed mo

th an 0.2 co. of the fifth norm al h yd roch loric acid .




Unity, followed by 10 to 15 dro ps of Nessler 's reag ent. A t

most only a faint yellow, but in no case a brownish-red,

color or precipi ta te should form.

ACID SULPHURIC, FUMING, WITH PHOSPHORIC AN-

HYDRIDE

APPROXIMATELY 5, 10, 15, 20, OR 2 5 % P2O5

Fuming su lphur ic ac id con ta in ing phosphorus pen tox ide ;

the usual grades co ntain app rox im ately 5 , 10, 15, 20, or 25per cent of P 2O S . Th e pre par at io n is used in K jeldahl 's



4 2 CUK MICAL ittiAd'HtVTS

CUBES FOR GENERATING SULPHU ROUS ACID

Cube-like pieces, containing at least 20 per cent of s

phurous ac id .

TIOST OK STHKNCTII

Quantitative Determ ination. Intro du ce 1 gm . of the fin

powdered cubes and 5 gm. of anh ydr ous sodium ra rb on

int o a grad uate d flask of 100 er. ra pa ci ty ; add 50 re .

water, boil the mixture, for about ten minutes, allow to co

fill the flask up to the mark, and filler. Run the filtr

from a burette into a constantly shaken mixture of ;>()

of dccino nnal iodine solution and 10 re. of hydroc hloric ac

until complete decoloration ensues.




W ater . — On dry ing ta nn ic acid a t 100° C , i t should no t

lose more than 12 per cent of i ts weight .

seeOTE. — Regarding the quantitative determination of tannic acid,Fresenius, Anleitung zur quantitativen Analyse, Vol. II, 619 [or Lunge,Chem.-tech. Untersuch.-Meth., 4 ed., 3, 560 ff. (1900)]; Fresenius-CohnQuantitative Analysis, Vol. II, 767 ff. (1904).

ACID TARTARIC

C4H6Oo. Mol. Wt. 150.04.

Colorless, prismatic crystals, or crystalline crusts, soluble

in 0.8 part of water, and in 2.5 parts of 85 per cent



4 4 CHEM ICAL HblMiblSTS

ACID THIOACETIC

cuiaO os ii. Mol. \V( . 7r».n«».

A yellow liquid of penetrating odor, boiling betw

an d 97° C , and h avin g a specific gra vity of 1.070. T h iacid is soluble in 10 pa rts of wa ter, and easily in a

The 0 per cent aqueous solution is used instead of hy

sulphide in chemical analysis.*

TKSTS OK PURITY

Non-volatile Matter. 10 ec. of thio aee tie a cid, onevaporated and ignited, should leave no weighuble re

Sulphuric Acid. On dissolving .1 ee. of th ioue elie




Fusel Oil.* — On mix ing 10 cc. of alcohol a nd 30 cc. of

water in an Er lenmeyer f lask, no turbidi ty or colorat ion

should be observed, nor should any foreign odor be noticeable.

A m ixt ure of 10 cc. of alcohol and 0.20 cc. of 15 per cent

sodium hy drox ide solut ion, when eva porated down to 1 cc ,

and supersaturated with di lute sulphur ic acid, should nothave the odor of fusel oil.

On rubbing a few drops of a lcohol between the hands , no

unpleasant odor should be not iceable .

Molasses-Alcohol. — On ove rlayin g 5 cc. of alcohol on 5 cc.

of concentrated sulphuric acid, no rose-red zone should form

within one hour a t the contact-sur faces of the two l iquids .

Aldehyde. — On warming 10 cc. of alcohol with 5 drops of

silver ni tra te so lution a nd 1 cc. of wa ter for ten minu tes on



4 6 CUKMWA h UK A(!KNTS

II

ALCOHOL, 9 5 %

A clear, colorless liquid of abou t, O.Nlo' specific g ra v it y(15.6° C ) , and containing abou t 05 per cent by volum e of

absolute alcohol; C 2II 5OIL I t boils a t 7<Sa (!., is miscible in

all proportions with water, and does not change the color of

mois tened l i tmus paper .

TENTS OK PIT HIT V

Residue. — 50 cc. of alcohol, on being slowly e va po ra te d,should leave no weighablo residue.

Fu sel Oil. — Mix 10 cc. of alcohol, 5 ce. of w ate r, a nd 1 cc .



CUtiMICAL 47

A L C O H O L A M Y L I C

<*AIIII -OH . Mol. W(, 88.07.

I

AMYL ALCOHOL

A clear , co lorless liquid , neu t ra l to l i tmus pap er . A m yl

alcohol is hu t s l ight ly solub le in water , bu t is clear ly misc ible

wi th a lcohol , e ther , and benzin . I t ha s a spec if ic gr av i ty

of O.KM and boils at VM° 0 .

TKSTK OK PURITY

Non-vola t i le Ma t t er .™ 10 gm . of amy l alcohol e va po ra te d

on the water -ba th should leave no weighable res idue .Fore ign O rganic M at ter (F ur fura l , e tc . ) . —

(a ) O n shak i ng .r> ce. of am yl alcoh ol with 5 cc. of co n-



4 8 CUUMH'AL HHAatiSrs

ALCOHOL METHYLIC

Cii ;t.;> n. Mol. Wt. :iv!.o:«.

A colorless, mobile liquid, readily misciMe in all pr

tions with water, alcohol, ether, and I 'ally and volatile M ethyl alcohol has the specific grav ity 0 .7% , and

betw een 05 and (>C>° ( \ It should not red den blue li

pa pe r .

THSTS ()!•' ITHITV

Non-vo latile Matter. .'{() ee. of methyl a lcohol ev ap or

on the water-bath should leave no weighaMe residue.Acetone and Ethyl Alcohol. Shake toge ther thorou

v




ALPHANAPHTHOL

CioH7-OH. Mol. Wt. 144 .06.

Color less , lus trous needles ; having a phenolic odor , and

me lt ing at 95° C. Al ph an ap hth ol is dif ficult ly soluble in

cold water , more readi ly soluble in warm water , and dissolveseasily in alcohol, ether , benzene, and chloroform.

TESTS OF PURITY

Inorganic Matter. — 1 gm. of a lphanaphthol igni ted on

plat inum foi l should leave no weighable res idue.

Organic Acids. — On shak ing 1 gm. of a lphanaphtho l w i th

100 cc. of w at er and filtering, th e filtrate sho uld n o t red de nblue l i tmus paper .



5() Cltlffllt'M* /MM*;'t:\TS

aluminuin oxide is vigorously shaken for five minute

200 ee. of a solution of •!./> tfiu. of pure tannin in Nu

w ate r to mak e 1000 ec. ( t 's e a Husk wit It a ru bb er S u

T he m ixtu re is then heated for five min ute; , on ( he

ba th , and fi ltered. «r>0 ee. of the fi l trate are ev ap or at eweighed platinum or nickel dish, and the residue dr

105° C. and weighed.

The total residue obtained from f>0 vv , of the o

tan nin solution, and dried at 105" ( \ , is nUu asc'er

On now calculating the residue for 'J00 ee. of tannin .u

and deducting this from the total residue left from the solution treated with the aluminum oxide, the reMiIt .

show t ha t 1 gm . of alu m inu m oxide absor bs 0,10 to 0,5




TESTS OF PURITY

Non-volati le Matter . — On eva por ating 3.5 cc. of th e am -

monia water on the water-ba th , no weighable res idue should

rem ain. A trac e of residue, however, is almo st alw ays left .

Chlor ides ; Pyr id ine . — Dilute 3 .5 cc . of the ammonia water

with 30 cc. of wate r, an d su per satu rate w ith 20 cc. of n itricacid. The solution should remain colorless . This l iquid

should show no change on the addition of s i lver nitrate solu-

t ion .

Heavy M eta ls. — On di lu t ing 2 cc. of the am m onia wa ter

with 20 cc . of water , and then adding a few drops of ammo-

nium sulphide solution, no change should appear.

Sulpha tes . — Slightly acidify 3.5 cc. of the am m on ia w ate rwith hydrochlor ic ac id , and add bar ium chlor ide solut ion.



52 VIIEM U \\ L UEAU E\ VS

Am mon ia W ater 2S per cent , are to be ma de. Hut , in

of 3.5 ce. of the 2N per cen t use 5 ce. of ( he L!0 per cen t

mo nia. The prepara tion should also conform to the follo

testa.

Sulphides. On add ing a few drop:; of an an uu ou

lead ace tate solution to f> ce. of the am m on ia w ate r,

liquid m ust no t acquire a yellow or a brown color , nor : h

a dark precipitate form.

Tar-Bases (Aniline, Pyridine, Pyrrol, v.tc.h K va p

a m ixtu re of 5 e c of t he am m on ia wa ter an d l!U <*c. of

acid on the wate r -bath . Th e res idue on eva po rat ion sh

have a pure white color .Calcium. -A. m ix tu re of f> cr , of the am mo nia w

with 20 ce. of water should ex hib it no tur bid ity on




TESTS OF PURITY

The tests of pur i ty and detai ls of execution are the same

as those given und er Am mo nia W ater , 20 per cent . B ut ; in

test ing this use double the quanti t ies of ammonia water

employed in test ing the 20 per cent .

AMMONIUM ACETATE

NH4OaH«Oa. Mol. Wfc. 77.1.

A white, hygroscopic, crystalline mass, easily soluble in

water and in a lcohol.

TESTS OF PURITY

Non-volatile Matter. — 3 gin . of amm onium ace ta te , when




TESTS OF PURITY

Non-volatile M atter . — 5 gm . of am m oniu m carb

when ignited, should leave no weighable residue.

Sulphates. — Dissolve 5 gm . of a m m on ium car bo n

100 cc. of water and 10 cc. of hydrochloric acid, he

solution to boiling, and add ba rium chloride solution

precipitate of barium sulphate should form on st

twelve hours .

Chlorides and Th iosu lpha tes. — Th e solutio n of 2

am m oni um carbo nate in 50 cc. of wa ter should n ot be a

on adding 10 cc. of .nitr ic acid, followed by silver




chloride in 20 cc. of water, and add to the clear solution 3 cc.

of magn esia m ixture and 10 cc . of amm onia wa ter . N o

prec ipi ta te should form on s tanding twelve hours .

Heavy Meta ls and Ear ths . — 20 cc . por t ions of the aqueous

1: 20 solution of the sal t should no t be affected by hy dro ge n

sulphide water , ammonia water , ammonium sulphide solu-t ion, and ammonium oxala te solut ion.

Sulp hates. — On a dd ing to 10 cc. of the 1:1 0 solu tion a

few drops of hydrochloric acid, fol lowed by barium chloride

solut ion, no prec ipi ta te of bar ium sulphate should form on

s tand ing twe lve hours .

Sulphocyanates . — Dissolve 1 gm. of am mo nium chlor ide

in 10 cc. of water, and add to the solution a few drops of

hyd roch loric acid and 1 drop of ferric chloride s olutio n.




semi-normal potass ium hydroxide solu t ion , us inorange as indicator.

1 cc. of semi-normal H 2SO 4 - 0.00702 gm . of N

= 0.00853 gm. of NH 3 , log. 9309.

AMMOmUM DITHIOCARBONATE SOLUTI




25 cc. of water, and adding a few drops of ni tr ic acid, fol lowed

by s i lver n i t ra te solut ion, the l iquid must exhibi t no change .

Sulph ates and Silicofluorides. — Dissolve 5 gm . of am m o -

nium fluoride in a plat inum dish in 25 cc. of water, and add

25 cc. of hydrochloric acid, fol lowed by barium chloride

solut ion. No turbid i ty should ensue .Heavy Meta ls . — Dissolve 5 gm. of amm on ium f luor ide in

25 cc. of water, add to the solution a few drops of hydro-

chloric acid, and 10 cc. of hyd rogen sulphide wa ter . N o

change should appea r . Now add amm onia w ater to a lka-

l in i ty , and a few drops of ammonium sulphide solut ion; a t

most a sl ight greenish colorat ion may develop, but a precipi-

tate should not form.



58 CHEM ICAL REAGENTS

in 10 cc. of water, and acidifying the solution with

no change should be observed on the further a

bar ium ni t ra te so lu t ion .

Chlorides. — 20 cc. of t he 1:1 0 aque ous so lutiow ith nitr ic acid should show n o change on the a

silver nitrate solution.

Quantitative Determ inat ion . — The content of

anhydr ide may be approximate ly de termined

igniting abo ut 1 gm . of the salt until the am mo n

has disappeared, and then weighing the residue oanhy dr ide ; i t should amo un t to abou t 81 per




AMMONIUM OXALATE

* + HaO. Mol. Wt. 142.16.

Colorless crystals, clearly soluble in 25 parts of cold water .

The aqueous so lu t ion shou ld be neu t ra l to l i tmus paper .

TESTS OP PURITY

Non-volatile Matter. — 3 gm. o f amm onium oxa la te on

ignition should leave no weighable residue.

Sulphates. — Dissolve 5 gm. of am mo nium ox ala te in

200 cc. of water , heat the solut ion to boi l ing, and then add

10 cc. of hydrochloric acid, followed by barium chloride

solut ion. No precip i tate of bar iu m sulph ate should form on




TESTS OF PURITY

Alkalies . — Th e solut ion of 2 gm . of am m on ium ph os ph ate

in 100 cc. of water is treated with lead acetate solution in

slight excess to precipitate the phosphoric acid, and is then

filtered. T he excess of lead in th e filtrate is th e n pr ec ip ita te dwith hydrogen sulphide, the l iquid f i l tered, the f i l trate evap-




AMMONIUM SULPHATE

(NH.,),K(.).,. Mol. Wt. 132.14.

Colorless crystals , soluble in 2 parts of cold, and in 1 part

of boiling, water; insoluble in alcohol.

TESTS OF PURITY

Ron-volat i le M atter . — 3 gm. of am mo nium sul ph ate on

ignitio n should leave no weigh able residue.

Chlor ides . — Th e solut ion of 2 gm. of amm oni um sulp hate

in 20 cc. of wa ter should no t beco me turb id on acidifying

with ni t r ic acid and then adding s i lver ni t ra te solut ion.

Heav y Metals . — Th e solut ion of 2 gin. of am m on ium

su lp ha te in 20 cc. of w ate r should rem ain unaffected by



62 CHEMICAL HEAtiESTS

TI-STS <)K ITUITY

Non-volat i le Matter . 2 gm. of a m m o n i u m s u l p h o c

on being ignited, should leave no weighable residue.

Substances insoluble in Alcohol. 1 gm. of a m msulphocyana te should comple te ly d isso lve in 10 cc. of a

alcohol, and yield a perfectly c lear solution.

Sulphates. On a dd ing a IVvv drops of hydrochlor i

followed by barium chlor ide solution, to a solu t ion of

of a m m onium su lphoc ya na te in '20 cc. of wa te r , no r

should be observed within f ive minutes.

Heavy Metals . On dissolving 1 gm. of a m m o n i u

p h o c y a n a t e in 20 ce, of wa te r , and a dd ing to the s




Ammonium Carbonate. — On addin g 3 cc. of calcium

chloride solution to 10 cc. of ammonium sulphide solution,

no prec ipi ta te should form, even on warming.

AMMONIUM THIOACETATE SOLUTION

( S C H I F F ' S R E A G E N T )

CHa. COSNILi. Mol. Wt. 93.15.

A clear, yel lowish l iquid, having a faint odor resembling

tha t of ammonium sulphide , and s l ight ly a lka l ine to l i tmus

pap er . The solut ion conta ins abo ut 30 per cent of amm on ium

th ioace ta t c .TESTS OF PURITY

Non-volatile Mat te r. — 1 0 cc . of amm onium th ioace ta t e

solution on evaporation and ignit ion should leave no weighable



(M CllK MlCAt* HK AtiblSTX

Aiiiliiu* is soluble in about .$/> \mvt^ of wafer . If so

in a. freezing mixture, and then mel ts at S" (

specific gravity is 1.027; its boiling point, itt.T" ( \

TKSTS OK i r i U T Y

Hydrocarbons and Nitr ob en zen e. "> cc. of ani l ine di

in 10 cc. of hydrochloric acid should form a clear fluid

on beinp; dil ute d with If) ec. of water , should not b

cloudy on cooling.

NOTK. liV :̂ inline tin* <"\:ifiiin:it i«»ii <>1 ;tttiltiit*, .*«<•«• I,ung<\ ('hrtI'ntrr.surh.Mrth., I <•<!., 3, 7I.'» <HH)(h; <M.jnpurr W.-IMN

11 Hrt, n

coiupim) Thorpe's Diet. <>l AppM. ( 'hnu. , 'J rd,, I, HY 2




aid of heat in 30 cc. of sodium hydroxide solution (sp. gr . 1.3).

Add to the solution 70 cc. of nitr ic acid, f il ter , and to the

f i l t rate add s ilver ni t r ate solut ion. The l iquid m ay exh ibi t

at most a s l ight turbidi ty , but no precipi tate should form.

ARSENIC TRIOXIDE

( A R S K N O U S A C I D ; ( A C I D ) A R S K N O U S A N H Y D R I D E )

AsaOa. Mol. Wt. 198.

White, v i t reous, or porcelain- l ike pieces , or white powder ,

soluble in 15 par ts of boi l ing water .

TESTS OF PURITY

Non-volatile Matter. — 1 gin. of arsenic tr ioxide cautiously



(if) VllhlMlt'M. tiblMWSTS

I co. of dce ino nn al I 0.00105 p n . of As 3O a, Io

NoTi'j. Both the lump and the powder fonun of arsenic trianswer the above requirements. The teats hen* tfive n should out with tluv powdered preparation, a.s tho wlude pitTt\s or htmp.

with dilliculiy.Hogardiug tl»» n.sn of arnriue trio\i*l«* in voltimetrir analysis,Lehrl>. ('hmn. anal. TitritM'ineth., 7 ed., p. »iS<,MT. (IHNli); SuttoAnal., 9 cd., p. i:tt) (l»()4).

AZOLITMIN

Azoli tmin is a par t icu lar ly p urr , water-solu ble

mat te r made

1

from litm us . It occu rs in the form of violet scales.




TESTS OF PURITY

Chlorides. — Th e solution of 1 gm. of ba riu m ac eta te in

20 cc. of watcr ; acidula ted wi th ni tr ic ac id , mu st exh ibi t no

turbidi ty on the addi t ion of s i lver n i t ra te solut ion.

Calcium and Alkalies. — Dissolve 5 gm. of bar iu m ace ta tein 200 cc. of water, add to the solution 2 cc. of hydrochloric

acid and h ea t to boil ing. No w add 15 cc. of 16 per cen t

sulphuric acid, al low to stand twelve hours, f i l ter , and mix

th e fi l t rate w ith 85 per cent alcohol. A t m ost a faint opale s-

ccnce should be observed; and on evapora t ing in a p l a t i n u m

dish and igni t ing, not more than 0 .004 gm. of res idue should

r e m a i n .Heavy Metals. — 20 cc. of the 1 : 20 aqueous solution sho uld




sulphuric acid, allow to stand twelve hours, fil ter, an

the f i lt rate with 85 per cent alcohol . N ot mo re th an

opalescence should be visible, and on evaporating in a

num dish and ignit ing, not more than 0.003 gm. of should remain.

Heavy Metals . — N eithe r hydro gen sulphide w ate

ammonia water wi th ammonium sulphide solu t ion ,

produce a dark color or a precipi tate on being adde

solution of 1 gm. of barium carbonate in 5 cc. of hydro

acid and 15 cc. of water.

Chlorides. — Th e solutio n of 1 gm. of bar iu m car




Strontium and Calcium Chlorides. — On sh aking 1 gm. of

powdered bar ium chlor ide wi th 20 cc . of absolute a lcohol

five minutes, and then fi l tering, the fi l t rate on being evapo-

rated and ignited should leave no wcighable residue.

Hea vy M etals. — 20 cc. of the 1 : 20 aqueous solut ion should

not a f ford a dark colora t ion nor a prec ipi ta te when hydrogensu lph ide wa te r is add ed ; nor when ammonia wa te r and

ammonium su lph ide so lu t ion a re added .

Nitrates. — On ad ding 1 dro p of a 1:1000 indigo solution

to a solution of 1 gm. of barium chloride in 10 cc. of water,

the blue color must not disappear on the addit ion of 10 cc.

of concent ra ted sulphur ic ac id .

Chlora tes . — On w armin g 2 gm. of powdered b ar iu m chlo-

r ide wi th 10 cc . of concent ra ted hydrochlor ic ac id hi a tes t




sulph ate solution, using starc h solution as the indi

least 9.7 cc. of decinormal sodium thiosulphate

required.

1 cc. of decinormal Na 2S2O 3 = 0.00847 gm. of

92788.

BARIUM HYDROXIDE

( B A R I U M H Y D R A T E )

Ba(OH)2 + 8EM). Mol. Wt. 315.54.

White crystals, soluble in 20 parts of cold, and

of boiling, water, a trace of barium carbonate almriably remaining undissolved . Th e aque ous solutio




hy dro xid e in 100 cc . of water , a dd 1 drop of meth yl orange

solut ion, and t i t ra te w i th nor m al hydrochlor ic ac id . N ot

less than 6.3 cc. of the normal acid should be necessary to

produce the red end-point .

1 cc . of nor m al I IC1 - 0 .15777 gm. of B a( 0 H ) 2 + 8H 2O ,

log. 19802.BARIUM HYDROXIDE SOLUTION

( B A R Y T A W A T E R )

A clear, colorless l iquid, of strongly alkaline reaction.

Baryta water conta ins 3 .3 per cent of c rysta l l ized bar ium

h y d r o x i d e , B a ( 0 H ) a + 8H 2O .

TESTS OF PURITY

Th e t e s t s t o be made a re those g iven unde r B a r ium H y-



72 (UlluMlCAI. A7-.\W/A.\7W

Alkalies and Heavy Metals. Tin* test is to be curr

as described under Barium Chloride.

BARIUM SULPHIDE

(fray, hard, amorphous pieces, prepared by fusing a-

of IK'.'ivy spar, powdered coke, and sodium chloride.On allowing hydrochloric acid to How over barium s

a uniform current of hydrogen sulphide should be ge

TKST OK PI'lilTY

Arsenic. Heat 100 cr. of nitric acid f.̂ p. <*;r !.

porcelain dish to 70 to NO" ('., and add 10 ^m. of fine

dered barium sulphide, gradually, in cjiiantitics of O.pu. at a time; when all has been added, heat to

Then add to the mixture 100 ec. of arsenic-free, dil




solidifies at 0° C. to rhombic, crystall ine scales, which melt

at + 4 ° C. It s specific g rav ity is 0.883, an d i t boils a t

80.5° C.

TESTS OF PURITY

Thiophene.* — On shaking 50 cc. of benzene with 20 cc. ofconcentrated sulphuric acid, the sulphuric acid should remain

colorless; on now adding a crystal of isatin, and again shaking

and al lowing to s tand one hour , the sulphuric acid should

have neither a green nor a blue color.

Carbon Disulphide.j — Tho roug hly mix 50 cc . of benze ne

with 50 gm. of a lcohol ic potass ium hydroxide solut ion (11 gm.

of potass ium hydroxide in 90 gm. of absolute a lcohol ) , andal low the mixture to s tand several hours a t a temperature




and 2 gm. of potassium nitrate, and cautiously

a platinum crucible. W hen cold, dissolve the m

of water, filter, add to the filtrate 20 cc. of hydr

and heat to boiling. On now adding bari um c

tion, no precipitate of barium sulphate shoustanding twelve hours .

BENZIN

( P E T R O L E U M E T H E R ; P E T R O L E U M B E N

A colorless, non-fluorescent, very inflammab

strong but not unp leas ant odor. Specific grav

0.670. Benzin distils betwee n 4 0 and 75° C , asolidify at 0° C.*




TESTS OF PURITY

Ca rbon ates, Lead, Copper, Salts of the Alkalies, etc . —

0.5 gin . of b ismuth subni t ra te should comple te ly dissolve in

25 cc. of cold 16 per cent su lphu ric acid with ou t th e evolu -

t ion of carbon dioxide, and should yield a clear solution.10 cc. of this solution, w ith a n excess of amm on ia w ate r,

sho uld yield a colorless f i l t rate. A noth er 10 cc. of this

solut ion, d i lu ted wi th 100 cc . of water and t rea ted wi th

hydrogen sulphide to comple te ly prec ipi ta te the bismuth,

should yield a f i l t rate leaving no weighable residue on evapo-

ra t ion and igni t ion.

Chlorides. — On addin g si lver ni tra te solution to a so lutionof 0.5 gin. of bismuth subnitrate in 5 cc. of ni tr ic acid, not




BROMINE

Br. Atomic Wt. 79.96.

A dark red, almost black l iquid, of specific gr

2.99, and boiling at 63° C. Brom ine dissolv

30 pa rts of w ate r. I t is easily soluble in al

chloroform, and carbon disulphide.

TESTS OF PURITY

Non-volatile Matter.— 5 gm. of bromine wa rm e

lain dish on the w at er -b ath should volati l ize

weighable residue.

Sulphuric Acid, Chlorine, and Organic Bro min e

(Bromoform; Carbon Tetrabromide). — 5 gm. of




and acidulate the fi l t ra te with ni tr ic acid. On ly a

slight opalescencc should develop.*

Iodin e. — Dissolve 1 gm. of brom ine in 4 0 cc . of wa ter ,

add 4 gm. of powdered iron, and shake two to three minutes.

Fil ter , add starch solution to the f i l t ra te , and cautiously

allow a few drops of bromine water to flow upon the surface.

A blue zone should not form at once below the yellowish

upper por t ion of the l iquid.

B R OM I NE WATER

A sa tu ra ted , aqueou s so lu tion , conta in ing abou t 3 per cent

of Br.TESTS OF PURITY




in 85 per cen t alcohol, and in chloroform. T

solution of brucine is alkaline to li tmus pa per , a

gyra te . W hen dr ied a t 100° C , brucine me lts a t

TESTS OF PURITY

W ater of Crystal l izat ion. — 1 gm. of brucin100° C. to constant w eight should lose no t more th a

Nitric Acid. — 0.01 gm . of brucine shou ld d isso

of pure concentrated sulphuric acid, and yield a c

at most, scarcely perceptible faint pink color.*

Strychnine. — Tr eat 0.5 gm. of brucine w ith

absolu te a lcohol a t the ord inary tempera ture fo

with f requent shaking . Fil ter , t ransfer a por t

undissolved substance to a watch glass, a l low i t




Cadmium and potassium iodide readi ly acqui res a s l ight

yellowish color on keeping.

TESTS OF PURITY

Foreign Metals. —

(a ) Dissolve 1 gin . of cadm ium and potassium iodide in

20 cc. of water, add to the solution 2 cc. of potassium

hy dro xid e solution, and fil ter. Ne ither before nor

af ter ac idula t ing wi th hydrochlor ic ac id should the

fi l t rate yield a precipitate with hydrogen sulphide

wa te r .

(6) Dissolve 1 gin. of cad m ium a nd p otassiu m iodid e in

30 cc. of water, and add to the solution 5 cc. of

amm onia water . Th e l iquid should rem ain c lear

and colorless on shaking.



SO CHEMICAL ?ttiA(W\TS

Heavy Metals.- -Dissolve I gm. of calcium carbonate*

5 cc. of hydrochloric, acid and 2 5 ce. of w ate r. T h is s

tion should not afford a precipitate or a green color

hydrogen sulphide water ; nor with ammonia water in ex

accompanied by 2 to 'A drops o f ammonium su lph ide so lu t

M agne sium . Dissolve* 1 gm . of calcium c ar b on a te

5 cc. of hydroch loric acid and 5 cc. of water . T o th is s

tion ad d .10 cc. of am mo nia wa ter and an rxeiw o f a m m o n

oxalatc solution, allow to stand live hours, f il ter , and

to the f il t rate sodium phosp hate solut ion. No pre cip i

should form on standing twelve hours.

Sulphates. Dissolve 1 gin. of calcium carbon ate4

in f>of hydrochloric acid and 25 cc. of watt1! ', boil the solu




TUSTS OF PURITY

Substances Insoluble in Absolute Alcohol. •— 2 g m . of cal-

cium chlorid e .should com plete ly d issolve in 2 0 cc. of ab -

solute alcohol .

He av y Me tals . 20 ce. of the I : 10 aqu eou s solut ion shou ld

show no change on adding I ce. of hydrochloric acid and

hydrog en sulphide wa ter . On fur ther addin g 5 cc . of am -

mo nia w ater and 2 to «{ drop s of amm onium sulphid e solu-

t ion, no green color should develop, nor should a precipi tate

form.

Sulphates . On add ing bar ium chlor ide solu t ion to the

so lut ion of 2 gin . of calc ium chloride*, in 20 cc. of w at er ac id -

ulated with 0.5 cc. of hydrochloric, acid, no precipi tate should

form on s tanding twelve hours .




of carbon dioxide, as in elementary analyses, but i t should

be previously rendered neutral by means of carbonic acid.

CALCIUM CHLORIDE FUSED

W hite crystal l ine m asses; formula: practical ly CaCl2. Fused

calcium chloride is chiefly used for drying liquids, e.g., e the r sesters, ethereal oi ls, hydrocarbons, etc.

CALCIUM HYDROXIDE

( S L A K E D L I M E )

Ca(OH)2. Mol. Wt. 74.11.

A white, dry powder.The art icle is tested as to puri ty by the methods detai led



C UKMIC AL UKAGKN TR 83

wnter, dissolve in 20 ee. of nitr ic acid, and dilute the solution

w ith 10 cc. of wa ter . T he solution should show no ch an ge

on the addition of silver nitrate solution.

Iro n. Slak e I gin. of calcium oxide with 5 cc. of w at er ,

an d dissolve in 10 cc. of hydrochloric, acid. T h e s olut ion

should not immediately afford a blue color on adding 0.5 cc.of potass ium fer rocyanide solut ion.

CALCIUM OXIDE, FROM MARBLE

(LIMIO)

OaO. Moi. wt. r>(u.

Whi te p ieces o f g ranu lar s t ruc tu re which develop muchheat on being spr inkled with water , and which become con-




CALCIUM PHOSPHATE, DIBASIC

( S E C O N D A R Y C A L C IU M P H O S P H A T E ; D IC A LC IX JM P H O S P H A T E )

CaHPO4 + 2H2O. Mol. Wt. 172.14.A white, crystall ine powder, easily soluble in hydrochloric,

nitric, or phosphoric acid, without effervescence; it is diffi-

cultly soluble in water, and in cold acetic acid.

Dicalcium phosphate does not dissolve in boiling water

without decomposition; i t produces a l iquid of acid reaction

and an amorphous residue, the composition of which approx-imates that of the neutral sa l t .



CHEMICAL REAGENTS

CALCIUM PHOSPHATE, MONOBASIC

( C A L C IU M B I P H O S P H A T E ; C A L C IU M A C I D ( O R S U P E

P H A T E ; P R I M A R Y C A LC IU M P H O S P H A T E ;

M O N O C A L C I U M P H O S P H A T E )

Ca(H2PO4)2 + HoO. Mol. Wt. 252.14 .

Colorless, pearly scales, which readily deliquesce Calc ium biphosphate d i sso lves in much water ,




CALCIUM PHOSPHATE, TRIBASIC

( T E R T I A K Y C A L C I U M P H O S P H A T E ; T R I C A L C I U M P H O S P H A T E )

Ca3(PO4)2. Mol. Wt. 310.3.

A white, amorphous powder, insoluble in cold water.

Tricalcium phosphate is gradual ly decomposed by boi l ing

water into an insoluble basic salt and an easily soluble acid

salt . I t is easily soluble in hyd roch loric or nitric acid, a nd




TESTS OF PURITY

Iron, Magnes ium, and Alka l ies . — On warm ing 2 gm . of

calcium sulphate with 10 cc . of hydrochlor ic acid and 100 cc .

of water , a c lear solution should result , which, on the addi-

t ion of 15 cc . of ammonia water and a few drops of ammo-nium sulphide solution, should not acquire a greenish or

dark color . To the so lu t ion , no m at te r wh e ther a prec ip i ta te

of ca lc ium sulpha te has formed or not , add ammonium

ox ala te solu tion in slight exces s, f ilter, ev ap or ate the filtrate,

and igni te in a p la t in um dish . There should no t rem ain a

res idue weighing more than 0 .001 gm.

CALCIUM SULPHIDE



gg CHEMICAL KKUii:\TS

Hydrogen Sulphide and Foreign Organic Sulphu

pounds. —

(a) On shaking 10 cc\ of carbon di*ulphidr wi

carbonates the hittt*r should not at*<|uin* u

color.

(6) On shaking 2 ee. of carbon dUtlphide in u dry

with a globule of metallic mercury, the

surface of the* lat ter should tint breojue

with a dark, pulverulent coating.

Sulphuric and Sulphurous Acids. (hi .haUim 10

carbon disulphide with f> <*t\ <> uutrr, thr l;itti*r

neither redden nor deeolori/t* bhu* litmus papi*r.




Regarding the preparation of carmine solutions and carmine tinctures,see Merck's Reagentien-Verzeichnis, p. 171 (1903); Cohn, Tests and Re-agents, p. 349 (1903).

Regarding the composition of carmine and of carmine ash, see S. Feitler,Ztschr. angew. Chem., 5, 136 (1892) [or Ztschr. anal. Chem., 32, 627

(1893)]; J. Soc. Chem. Ind., 12,256 (1893).

CHARCOAL, AMMAL

( B L O O D C H A R C O AL , P U R I F I E D B Y A C I D )

A d r y ; l ight , black powder.

TESTS OF PURITY




five minutes, filter, and to 10 cc. of the filtrate add 25 cc.

of ammonia water; the liquid should not acquire a blue color,

nor should a flocculent pre cip itat e form. On the further

addition of a few drop s of am mo nium sulphide a nd am-

monium oxalate solutions, no turbidity should develop

immediately.

Residue on Ignition. — 1 gm. of anim al cha rcoa l should

leave a residue weighing not more than 0.10 gm. on ignition.

Hydrogen Sulphide. — He at 1 gm . of anim al cha rco al with

40 cc. of water and 10 cc. of hydrochloric acid, and test the

escaping vapors with moistened lead acet ate paper . The

latter should not acquire a brown color.

Decolorizing Pow er. — Dissolve 50 gm . of cara m el (sugar

coloring; bu rn t sug ar) in 50 cc. of wa ter, a dd 100 cc. of

85 per cent alcohol, dilu te th e whole to 1 liter, allow to




1 cc. of deeinorm al N a 2 S A - 0.00354 5 gm . of Cl, log.

MW>2.

Hydrochlor ic Acid.* Sh ake 20 gm. of chlor ine wa ter

with about 5 gm. of pure mercury vigorously for f ive minuten.

Miter , add phenolphthalein to the solut ion, and run in

n o r m a l potass ium hydroxide solut ion, by drops , unti l a redcolor ap pe ars . Not more than 0 .1 cc. of norma l alkal i should

be required to produce the red end-point .

CHLOROFORM

(UKIla. Mol. Wt. 110.35.A clear, colorless, very volatile liquid, slightly soluble in

water (1:200), but miseible in all proportions with alcohol,ether, and fatty and volatile oils. Chloroform has a specific




of chloroform an d 15 cc. of co nc en trat ed su lph uri c acid

a glass-stoppered flask, 3 cm . wide , which ha s bee n ri

previously with sulph uric acid, the acid should no t acq

a color within one hour.

CHROMIUM TRIOXIDE — FREE FROM SULPHURIC A

( ( A C I D ) C H R O M I C A N H Y D R I D E )

CrO3. Mol. Wt. 100.01.

Dark, brownish-red needles, or rhombic prisms, readily soluble in wa ter. Ch rom ium trioxide co nta ins alm



CHEMICAL HE AGENTS 03

COBALT NITRATE

(COBALTOUS NlTKATK)

(V)(N();l), | (JUaO. Mol. Wt. 291,17.

Red, monoelinie pr isms, del iquescent in mois t air , andreadi ly soluble in water and in alcohol .

TKSTH OK PURITY

Sulphates. —- A solution of 1 gm . of coba lt n it ra te in

20 ec. of water , to which have been added 0.5 cc. of hydro-

chlor ic acid and a l i t t le bar ium chlor ide solut ion, should notbecome tu rb id .




COLLODION

A colorless, or slightly yellowish, ne utra l, sy rup y liqu

which, exposed in thin layers , evaporates, and leaves

toug h, colorless film. Collodion con tains abo ut 4 p er c e

of soluble cotton.TESTS OF PURITY

Acids. — Blue litmus pap er, wh en immersed in collodi

should not be reddened immediately.

Determination of Residue. — On evapo rating 10 gm.

collodion on the water-bath, it should leave a residue, whi

when dried at 100° C, should weigh 0.38 to 0.40 gm.



CUKMWAL HKAGlWrS 95

wash with ammoniaeal water unti l perfectly free

from copper. Inc ine rate the fil ter with an y pre -

c ipi ta te i t may conta in , and igni te . The residue

should not weigh more than 0.001 gm. ( i ron and

b i s m u t h ) .

(6) Dissolve 10 gm . of cop pe r in GO cc. of nitr ic acid ( sp .gr. 1.3) , add to the solution 15 cc. of c on cen trat ed

sulphuric acid (sp. gr. 1.84), evapora te the solut ion

on the water-bath as far as possible, and heat the

residue on a san d- ba th unti l the* vap ors of sulp hu ric

acid begin to be evolv ed. Dissolve the residue in

300 cc. of water, pass hydrogen sulphide gas into

the solution at 70° 0. unti l the copper is completely

precipitated, f i l ter , concentrate the fi l t rate, expel the




COPPER CHLORIDE, CUPRIC

( C O P P E R D I C H L O R I D E )

CuClo + 2HaO. Mol. Wt. 170.53.

Green, hygroscopic crystals, easily soluble in water, alcoh

and e ther .TESTS OF PURITY

Substances Insoluble in Alcohol. — T h e so lution of 5 g

of copper chloride in 5 cc. of water should not be render

turbid on mixing with 5 cc. of 95 per cent alcohol.

Sulphates. — Dissolve 1 gm. of copper chloride in 20 cc.

water, and add 0.5 cc. of hydrochloric acid, followed ba rium chloride solut ion. No tur bi di ty should ensue wit



CHUMICAL HEAGHNW 97

COPPER CHLORIDE, CUPROUS

((•OITKU MONOCHLOUIDIO)

VMJL%. Mol. Wt, I OH. I.

A w hite , crysta l l ine po wder , insoluble in wa ter , bu t soluble

in concentrated hydrochlor ic , acid and in ammonia water .rfhe quali ty of cuprous chlor ide may be judged from its

a ppe a r a nc e . Th e p r e pa r a tion shou ld be wh i t e , bu t n o t

green nor brow n.* Both th e hydroch lor ic acid and th e

ammoniaca l so lu t ions should rapid ly and f ree ly absorb

c a r bon m onox ide .

COPPER OXIDE

( O U P U K ) O X I D M )




hydrochloric acid (sp. gr. 1.19), dilute with water to 50 cc,

and add barium chloride solution. No imm ediate t ur bi di ty

should appear.

Calcium. — Digest 20 gm. of copper oxide w ith a m ix tu re

of 5 cc. of nitric acid an d 95 cc. of wate r for a bo ut fifteen

minu tes, shaking frequently; filter, precip itate the copp er inthe filtrate completely by passing hydrogen sulphide gas, and

filter again. Ev apo rate the filtrate on the w ate r-b ath to

about 20 cc, add ammonia water in excess, filter once more,

and to the filtrate add ammo nium oxalate solution . N o

immediate turbidity should be produced.

COPPER SULPHATE

(CXJPRIC SULPHATE)




with an y prec ipi ta te i t m ay conta in . The we ight of the

residue should not exceed 0.001 gm.

COPPER AND AMMONIUM CHLORIDE

( A M M O N I O - C U P R I C C H L O R I D E )

CuClo •2(NH4C1) + 2H2O. Mol. W t. 277.57.Blue crysta ls, giving w ith wa ter a clear s olution sl igh tly

ac id to l i tmus paper .TESTS OF PURITY

Free Acids. — A solutio n of 30 gm. of copper an d am m o -

niu m chloride in 100 cc. of w ater m us t be perfe ctly clear.

On introducing into the solution several pieces of piano wire,

the lat ter should dissolve with the deposit ion of copper, butwi thout any evolut ion of gas .




DIPHENYLAMINE *

(C«H«)aNH. Mol. Wt. 169.12.

White, monoclinic crystals, insoluble in water, but easi

soluble in alcohol, ether, and benzene. Diph enylam ine me l

at 54° C. and boils at 302° C.

TESTS OF PURITY

Nitric Acid. — 0.2 gm . of diphe nylam ine should dissolve

20 cc. of pure concentrated sulphuric acid with 2 cc. of wate

an d yield a colorless solutio n. Sho uld a blue color dev elo

the sulphuric acid should be tested with brucine for th

possible presence of nitric acid.

Aniline. — On pour ing 1 gm. of powdered dipheny lamin

into 20 cc. of a chlorinated l ime solution, the l iquid shoul




E T H E R

( E T H Y L E T H E R )

(C2H6)2O. Mol. Wt. 74.08.

I

ETHER, SP. GR. 0.720

A clear, colorless ; mobile liquid of specific gravity 0.720,*

boil ing a t 34 to 36° C. E the r should not redd en mois t blue

l i tmus paper . Fi l te r paper which has been mo is tened wi th

e ther should have no odor when dry .




bott le , the br ight surface of the metal must not be tarnishe

nor should a black precipitate form.

W ate r. — On shaking 20 cc. of eth er in a stop pered fla

with 1 gm. of anhy drou s copper sulphate , th e la t te r shou

not acquire a green or blue color.

I I

ETHER, ANHYDROUS, DISTILLED OVER SODIUM

TESTS OF PURITY

In addit ion to the tests given above, this preparation mu

answer the fol lowing requirement:On introducing 15 cc. of ether into a dry, glass-stopper




GALLEIN, LIQUID

( G A L L E I N )

A pale brow n coloring m atte r, co nsist ing of pyrog al-

lolp htha lein . Gallein in alcoholic solut ion is use d as anind ica to r .

G L Y C E R I N

( G L Y C E R O L )

C3H8O3. Mol. Wt. 92.06.

I






TESTS OF PURITY

The tests for arsenic, heavy metals , chlorides, substances

which reduce ammoniacal si lver ni t rate, free acids and

bases, oxalic , sulphuric and fa t ty acids, and inorga nic m at te r,

are to be made in the manner described under Glycerin,sp . gr. 1.250.

The fol lowing addit ional test is also to be made:

Ammonium Compounds and Organic Bodies Such as Occur

in Unpurified Glycerin. — O n h ea tin g 1 cc. of glyce rin w ith

1 cc. of sodium hydroxide solut ion, no ammonia should be

evolved ( to be de tec ted by means of mois tened l i tmus paper ) ;nor should a color develop nor an odor resem bling t h a t of



1 0 6 CHEMICAL REAGENTS

color, and in dilute sodium hydroxide solution, produci

bright-red color.HEMATOXYLIN

C16H14O6 + 3H2O. Mol. Wt. 356.16.

Colorless, or pale-yellow, tetragona l prisms, m el tin g

100 to 120° C. with loss of w ate r. On slowly cooling a s

t ion saturated a t boiling heat , hem atoxylin cr ystal l ize s

times in the form of rhombic crystals containing one m

cule of water of crystallization. He m atoxy lin is b ut sl ig

soluble in cold water and in ether, but is more solubl

borax solution and in hot water, and is easily soluble

alcohol. On exposure to light it gradua lly acquire s a

color, and then dissolves to form yellow solu tions .

ammonia water hematoxylin dissolves and yields a pu

solution. Hem atoxylin is used as an indica tor in 0.5




troduce 5 gm. of the hide powder into a bell-fi l ter, as de-

scr ibed by Procter ( see Lung e, Chem.- tech. U nter suc h. -

M eth. , 5 ed. , 3 , 715 (1 905) ; Allen, Com. Org an. An al. , 3 ed. ,

Vol . I l l , Pt . I , p . 83 (1900) ) . Then suspend the f il te r in a

beaker of about 150 to 200 cc. capacity, fix the s iphon, by

means of a clamp, so that the bell-fi l ter almost reaches thebot tom of the vesse l , and then pour in to the beaker a smal l

quant i ty of water in order to mois ten the h ide powder by

capi l la r i ty . After the powder has become mois t , which re -

quires about an hour, the beaker is fi l led, and suction care-

fully applied to the s iphon until the fi l trate begins to drop

slowly. T he fi l tration of 90 to 100 cc. requ ires abo ut on e

an d a half to tw o ho ur s. T he 30 cc. first sipho ned off a rere jec ted ; th e next 50 cc . a re evapora ted to dry ness on th e




TESTS OF PURITY

Sulphuric Acid. — Dilute 1 cc . of th e h ydro gen pero x

with 20 cc. of water, add 0.5 cc. of hydrochloric acid, heat

boil ing, and add bar iu m chlor ide solution. No p reci pit

of bar ium sulphate should form on standing twelve hoursResidue on Evapo ration (Sulphuric and Phosph oric Ac

e tc . ) . — 1 0 cc. of the hydro gen peroxide, when hea ted on

water-bath, should completely volat i l ize and leave no wei

able residue.

Oxalic Acid. — T he s olution of 2 cc. of hyd rog en pe rox

in 10 cc . of water should n o t becom e turb id on the ad dit

of calcium chloride solution.

Hy drochloric Acid. — Th e solutio n of 1 cc. of hy dr og




1 cc. of dec ino rm al KMnO< - 0.0017008 gm. of H 2O 2 , log.

23065.

HYDROGEN SULPHIDE WATER

A clear, colorless l iquid, having a strong odor of hydrogen

sulphide gas, and affording a voluminous precipitate of

sulph ur on the add it ion of ferric chloride solution. H ydr oge nsu lph ide water has an acid react ion to l i tmus paper .

HYDROXYLAMINE HYDROCHLORIDE

NH20H • HC1. Mol. W t. 69.52.

Dr y, colorless crystals, soluble in 1 pa rt of w at er and in

15 pa rts of alcohol, an d also in glycerin. Th e aq ue ou s solu-

t ion i s acid to l i tmus paper .




1 cc. of normal KOH = 0.06952 gm. of NH 2 O H ' H C 1 , lo g .

84211.

I N D I G O

I

SYNTHETIC INDIGO

A fine, dark-blue powder, containing at least 95 per cent

of indigo blue.

TESTS OF PURITY




incipient red color) is the sharp and dist inct ly visible end-

point of the t i t rat ion.

1 cc. of decinormal KMnO 4 = 0.007415 gm. of indigotin,

log. 87011.

I I

VEGETABLE INDIGO

Da rk-blu e, l ight pieces, which, on bein g rubb ed with a

ho rn spoon, or other ha rd substance s, exhib it a coppery-

me tal l ic luster . Good vege table indigo ha s a lower specific

gra vity th an wate r, hence i t f loats on the lat ter . I t should

contain at least 60 per cent of indigo blue.

TESTS OF PURITY

Ash. — 1 gm. of indigo should not leave more than 0.12 gm.




Mo isture. — On d rying 1 gm. of indigotin at 100° C.

constant weight, the loss of weight should not exceed 0.

gm .

Quantitative De termination. — This is to be carr ied ou t

descr ibed under Synthet ic Indigo.

IODEOSIN

( T E T R A I O D O F L U O R E S C E I N )

CaoHsI405. Mol. Wt. 835.94.

A scarlet-red, crystalline powder, yielding with alcoho

deep-red, and with ether a yellowish-red, solution. Iode o

is insoluble in water containing a trace of hydrochloric a

The solution used as an indicator is prepared by dissolv

1 gm. of iodeosin in 500 cc. of alcohol.




IODINE

( I O D I N E R E S U B L I M E D )

I. Atomic Wt. 126.97.

Blackish-gray, dry, rhombic plates or scales , wi th a metal l ic

luste r, easily soluble in alcohol, ether, and chloroform . Io di ne

dissolves in about 5000 parts of water , and is very freely

soluble in an aqueou s solut ion of potass ium iodid e. T he

preparat ion contains 99.98 to 100 per cent of I .

TESTS OF PURITY

Non-volat i le M at ter . — On caut iously he at in g 1 gm . of




IODINE WATER

A saturated aqueous solution, containing about 0.2 gm.

iodine in 1000 cc.

TEST OF STRENGTH

Titrate 100 cc. of iodine water with decinormal sodiu

thiosulphate solution.

1 cc. of decinormal Na2S2O 3 = 0.012697 gm. of I, log. 103

I R O N

Fe. Atomic Wt. 55.9.

Metallic iron is used in the analytical laboratory in form of thin, polished wire (piano wire), or gray powd




and also perfect ly rel iable substance for standardizing per-

manganate solut ions, i f we have once ascertained i ts effect ive

value compared wi th potass ium permanganate so lu t ion , the

t i tcr of which has been accurately determined by means of

some o ther s tandard .For a sat isfactory means of fixing the t i ter of perman-

ga nate so lu t ion , sodium oxala te may be recom me nded ( see

Sodium Ox ala te , Accord ing to Sorensen ) . Or * s tar t ing wi th

sodium bicarbo nate , then by dry ing a t about 300° C , thus

obta in ing sodium carbo nate , p repar ing a s tand ard so lu t ion

of this , from this preparing a solut ion of fi f th normal hydro-

chloric acid, from this a solut ion of fi f th normal potassium



116 CHEM ICAL REAGENTS

and 10 cc. of water over 1 gm. of reduced iron in a test tube.

Fi l te r paper mo istened w ith solution of lead ac eta te should no t

be darkened in color on exposure to the l iberated hydrogen

for ten seconds.

Sodium Carbonate. — On shaking 5 gm . of re du ced iron

w ith 50 cc. of w ate r an d filtering, t he filtrate sho uld n o t




potass ium perm anga nate unt i l a fa in t red color pers is ts .

At least 16 cc. of the permanganate solution should be re-

qu i red .

For the purpose of control, dissolve in the slightly recj

l iquid 2 gin. of potassium iodide, allow to s tand for one hour

in the s toppered flask at 20° C, and t i trate with decinormal

sodium thiosulphate solution, using s tarch solution as theind ica to r .

1 cc. of decinormal KMnO 4 or 1 cc. of decinormal Na 2S 2O 3

= 0.00559 gm. of Fe, log. 7 4 7 4 1 .

I l l

IRON POWDERA fine, heavy, gray powder with metall ic luster, and con-




Quantitative Determination. — Dissolve 1 gm. of pow dere d

iron in about 50 cc. of dilute sulphuric acid, and dilute the

solutio n to 100 cc. To 10 cc. of this solution a dd de cin orm al

potassium permanganate solution until the liquid has a slight

red color, and when the liquid becomes decolorized, whichm a y be effected, if nece ssary, by ad ding a few d ro ps of

alcohol, add 2 gm. of potas sium iodide. Allow th e m ix tu re

to stand one hou r in a closed flask at 20° C , and th en ti tr at e

w ith decinormal sodium thios ulph ate. At least 17.5 cc.

should be required to combine with the liberated iodine.

1 cc. of decinorm al N a2S2O 3 = 0.00559 gm . of Fe , log. 7 4 7 4 1 .




drops of potassium ferricyanide solution to the 1:20 aqueous

solution of ferric chloride; no blue color should develop.

Copp er, N itric Acid, etc. (A lkali Salts, Calcium ) . — Dilute

20 cc. of ferric chloride solution (1:1) with 100 cc. of water,

ad d 25 cc. of am mo nia water, and fil ter. On evapora ting

50 cc. of the colorless filtrate and igniting the residue, the

w eig ht of the latter should no t exceed 0.001 gm. On mixing2 cc. of the filtrate with 2 cc. of concentrated sulphuric acid,

and overlaying this mixture with 1 cc. of ferrous sulphate

solution, no brown zone should form at the contact-surfaces

of th e two liquids . 20 cc. of the filtrate a cidulate d With

acetic acid should not be affecte'd by potassium ferrocyanide

s o lu t ion .

Sulphates. — Dissolve 10 gm. of ferric chloride in 100 cc. ofwater, add 25 cc. of ammonia water, f i l ter, acidulate the




acid , yielding a pale-green solutio n. Iro n chloride i

soluble in alcohol

TESTS OF PURITY

Oxy chloride .— The s olutio n of 1 gm . of ferrous ch

in 1 cc. of water and 2 to 3 drops of hydrochloric acid sbe pale green or green in color, and should not hav

yellowish-green tin t. On add ing 5 cc. of sat ura ted hy d

sulphide water , the solution should show only a very

turbidity, due to the separation of sulphur.*

Sulphates, Copper, and A lkalies. — Boil for a few m

a solution of 5 gm. of ferrous chloride in 10 cc. of wate

5 cc. of nitric acid (sp. gr. 1.3), dilute to 120 cc, add 2

of am mo nia wa ter, and filter; evap orat e 50 cc. of th e f




TESTS OF PURITY

Substances Insoluble in Water. — Th e 1 : 20 solution, freshly

prepared wi th water which has previous ly been thoroughly

boiled and then cooled, should be clear and have a greenish-

yellow color.Alkalies. — A d d 5 cc. of nitric acid (sp. gr. 1.3) to a solu-

tion of 5 gm. of ferrous sulphate in 100 cc. of water, and

boil for several minutes; then add 15 cc. of ammonia water,

fi lter, and evap ora te the fil trate. Th e residue ign ited should

not exceed 0.001 gm. in weight.

Copper and Zinc. — Oxidize the solution of 2 gm. of ferrous

sulphate in 50 cc. of water by boiling with 3 cc. of nitricacid (sp. gr. 1.3) , the n add 8 cc. of am m oni a wa ter and




TEST OF PURITY

Quan titative D eterm ination . — Place 0.5 gm . of th e

powdered iron sulphide in a retort, in the tubule of wh

fixed a funnel-tube provid ed with a glass cock. Afte

necting the retort with a receiver containing 50 to 100 decinormal iodine solution, a l low to f low into the

through the funnel-tube, a mixture of 20 cc. of wate

20 cc. of dilute sulphuric acid; close the stop-cock, an

to boiling. After the decom position of the iron sulp h

complete , and the hydrogen sulphide has been entire ly

off (the iodine solution must not be fully decolorized),

mine the excess of iodine by means of decinormal s




(a) 2Q cc. of the fil trate should show no ch ang e on ad di ng

ammonium sulphide solut ion.

(b ) On acidifying 20 cc. of th e filtrate w ith ac eti c acid,

and then adding potass ium ferrocyanide solut ion,

the l iquid should show no change.

Alkalies . — To a solutio n of 5 gm. of ferric am m on iu msulph ate in 100 cc . of wa ter add 15 cc . of am m on ia wa ter ,

fil ter, an d eva po rate th e fil trate. Th e residue ign ited sh ou ld

not exceed 0.002 gm. in weight.

IRON AND AMMONIUM SULPHATE, FERROUS

( F E K R O U S A M M O N IU M S U L P H A T E ; M O H R ' S S A L T )FeS04(NH4)oS04 + 6H2O. Mol. W t. 392.'26.




Eva pora te 30 cc. of the f i l trate on the wa ter -ba th to d ryn

an d ignite. No weighable residue should rem ain.

Quantitative Determ ination. — Dissolve 1 gm. of fer

ammonium sulphate in 50 cc. of well-boiled and cooled wa

add 10 cc. of dilute sulphuric acid, and titrate with decinor

potass ium permanganate solut ion.

1 cc. of decinormal KMnO 4 = 0.039226 gm . of Fe

(NH 4 ) 2SO 4 + 6H 2O, log. 59358.

LACMOID

( R E S O R C I N O L B L U E )

Lustrous, dark-violet scales, soluble in alcohol, aceto




addit ion of 0.05 cc . of decinormal potass ium hy-

d r ox ide .

NOTE. — Regarding the use of lacmoid for th e titratio n of alkaloids,see C. Kippenberger, Ztschr. anal. Chem., 39, 214 (1900); J. Chem. Soc,78, II , 637 (1900). J. Messner, Ztschr. angew. Chem., 16, 4 4 4 ( 1903) ;J. Chem. Soc, 84, II, 519 (1903).

LEAD ACETATE

Pb(C,H3O2)2 + 3H2O. Mol. Wt. 378.99.

Color less , t ran s lu cen t crys ta ls , soluble in 2 .3 p ar ts of w at er

or in 29 pa r ts of 85 per cent a lcohol . All the aqu eou s solu -

t ions for tes t ing should be prepared with well-boi led water ,

to insure f reedom f rom carbon dioxide.

TESTS OF PURITY




LEAD CHROMATE

PbCrO4. Mol. Wt. 323.

A yellowish-brown powder, or brown lumps, insoluble in

water and ammonia water ; but a lmost completely soluble

in solutions of the fixed alkali hydroxides, and, with decom-

posit ion, almost wholly soluble also in concentrated nitric




TESTS OF PURITY

Chlorides. — Boil 5 g m . of lead p erox ide w it h 60 cc. of

w at er a nd 5 cc. of nitri c acid , filter, a nd to 30 cc. of the filtrate

ad d s ilver ni tra te solution. A t mo st a s l ight opalescent

tu rb id i ty shou ld appear .

Sulphates. — Digest 5 gm. of lead peroxide with 30 cc. of

a cold sat ura ted aque ous solut ion of sodium bica rbon ate for

thr ee or four hou rs , sha king frequently. The n f il ter, acidulate

the filtrate with hydrochloric acid, boil the solution for ten

m inu tes , and ad d 2 cc. of ba rium chloride solution. No

precipi ta te of bar ium sulphate should form on s tandingtwelve hours .




th e solution to the boil ing point , and al low sem i-nor

potassium permanganate solution to run into i t unti l

red color imparted b y 1 drop of the perm ang anate solu

no longer completely disa pp ears with in half a m in ute .

to 13.7 cc . of the semi-normal potassium permanganate s

tion should be required.1 cc. of semi-normal H 2C 2O 4 = 0.05973 gm. of PbO 2 ;

77619.

II

LEAD OXIDE BROWN, FOR DENNSTEDT'S ULTIMA

ANALYSIS

A dark-brown, amorphous powder , insoluble in water , ufor ul t imate organic analysis according to Dennstedt .*




Carbonates. — On p ouri ng nitr ic acid over 5 gm . of lead

peroxide, no evolution of gas should be seen, even when

observed th rough a magnify ing g lass .

Quantitative Determination. — This is to be carried out as

detai led under Lead Peroxide Free From Manganese.

LEAD OXIDE YELLOW

( L I T H A R G E )

PbO. Mol. W t. 222.9.

A yellow or reddish-yellow powder, almost insoluble in

water (1 :12000) , bu t so lub le in n i t r ic acid , acet ic acid , and

potass ium hydroxide so lu t ion .

TESTS OF PURITY




solution should no t disapp ear on the add ition of 10 cc

concentrated sulphuric acid.

Chlorides. — The solution of 1 gm. of lead oxide in 5 cc

nitric acid diluted with 20 cc. of water should not be affe

by silver nitrate solution.

Ear ths, Gypsum, and Alkalies. — Dissolve 1 gm. of oxide in 10 cc. of diluted acetic acid, add 100 cc. of w

an d supersaturate with hydro gen sulphide gas. Fil ter

the p recipitate, evap ora te th e filtrate, ignite the residu e,

weigh. The weight should no t exceed 0.003 gm.

LEAD SUBACETATE SOLUTION

A clear, colorless, liquid, of specific gravity 1.235 to 1.




gm. of the powdered cubes with a solution of 3 gm. of potas-

si um iodide in f i( ) cc. of wa ter , and add 5 cc. of hyd rochloric

acid . Ti t ra t e the l iberated iod ine wi th dccinorm al sod ium

thiosulphate solution, of which at least 35.2 cc. should be

r e q u i r e d .

1 cc. of dccinormal Na 2S 2O 3 - 0.00354 5 gin. of Cl ; log. 54962.

LIME WATER

( S O LU T IO N - O F C A T /H U M H Y D R O X I D E )

A clear, colorless l iquid having a strongly alkaline reaction.

TKST OF STRENGTH

Tit rate 100 cc . o f l ime water wi th normal hydrochlor icacid , us ing me thyl o range as the ind icator . N ot less than




and f il ter. Preserve the l i tmus t inc tur e in bo t

pletely f i l led, and simply cover with a loose c

with a plug of cotton to keep o u t the du st .

TEST OF SENSITIVENESS

Add 0.2 cc. of l i tmus t inc ture t o 100 cc. of di

and boil for some t ime in a p la t i n u m dish to

carbon dioxide. Th e violet co lor of the l iquid

must change to red on the addit ion of 0.05 cc.

hydrochloric acid; or must pass into a pure

the addi t ion of 0 .05 cc . of decinormal potassiu




Barium. — The solut ion of 1 gm. of m a g n e s i u m c a r b o n a t e

in 5 eo. of hydrochlor ic acid and 15 cc. of water shou ld not

be rendered turbid on the addi t ion of di lu te sulphur ic acid .

Calcium and Alumina. — Dissolve 1 gm. of m a g n e s i u m

c a r b o n a t e in 30 cc. of acetic acid (sp. gr. 1.041) and 30 cc.of w ate r. Boil, add 20 cc. of a m m o n i a w a t e r and some

ammonium oxa la tc so lu t ion . The liquid should not b e c o m e

turbid within f ive minutes .

Heavy Metals . -The solution of 1. gm. of m a g n e s i u m car-

b o n a t e in 20 cc. of acetic acid (sp. gr. 1.041) and 30 cc. of

water should bo clear , and should show no change wi th

hydrogen sulphide water .




and add 12 cc. of am monia water. No turb idity or preci

tate should form on standing twelve hours.

Ammonium Salts. — On heatin g 3 gm. of mag nesiu m ch

ride with 10 cc. of sodium hydrox ide solution (s p. gr. U

no vapors of ammonia should be evolved (to bo ascertain

by moistened litmus paper).

Barium. — The solution of 1 gm. of m agnesium chloride

20 cc. of water should afford no reactio n on the ad di tio n

dilute sulphuric acid.

Heavy Metals and Calcium.

(a) The solution of 1 gm. of magnesium chloride in 20

of water must not be affected by hydrogen sulphi

water.

(6) Dissolve 1 gm. of magnesium chloride in 20 cc.




Substances Insoluble in Hydrochloric Acid. — 1 gin. of

magnesium oxide should completely dissolve in 10 cc. of

hydrochloric acid and 10 cc. of water , yielding a clear solution.

Sulph ates . The solut ion of 0.5 gm. of ma gn esium oxide

in 10 cc. of ace tic acid (s p. gr. 1.041) should not be imme-

diate ly rendered turbid on the addi t ion of bar ium ni t ra tesolut ion.

Chlorides. • The solut ion of 0.5 gm. of ma gn esium oxide

in 10 cc. of nitr i c acid an d 10 cc. of wa ter shou ld n o t be -

come more than s l ight ly opalescent on the addi t ion of s i lver

n i t r a te so lu t ion .

Carbonates. * Heat 0.5 gm. of magnesium oxide with 10 cc .

of water , and pour this mix ture in to 10 cc . of di lut e acet icacid. Solut ion should tak e place with ou t any ef fervescence;



!3 6 CHEMICAL REAGENTS

II

MAGNESIUM OX IDE, FREE FROM SUL PH AT ES

TESTS OF PURITY

The tests as given for Magnesium Oxide should bo n

upon this article, and in addition the following one:Sulphates. — Dissolve 3 gin. of magn esiu m oxide in

cc . of hydrochloric acid, dilute the solution to about 100

heat to boiling, and add barium chloride solution . No

cipitate of barium sulphate should form within twelve h

MAGNESIUM SULPHATE

MgSO.t + 7H2O. Mol. Wt. 24 0.53.Clear, colorless, prismatic crystals, only very .slightly e



CHEMICAL ItNAGlWTS 137

MAGNESIUM AND AMMONIUM CHLORIDE

M tfV NII4CU I M l,O. Mol. Wt. 2JW.87.

Rhombic crys ta ls , or whi te c rys ta l l ine powder , eas i ly

soluble in wa ter. I ts princ ipal use is in the pr ep ar at io n of

magnes ia mixture for the de terminat ion of phosphoric ac id .

TftSTS OK PUIUTY

Sulphates; Heavy M etals; Calcium and Barium. — T h e t e s t s

are to be made as detailed under Magnesium Chloride.

Phosphates and Arsenates. - Dissolve 5 gm. of m agn es iu m

and am m on ium chloride in 10 cc. of wa ter, and a dd 5 cc. of

am mo nia wa te r . No tu rb id i ty o r p rec ip i t a t e s hou ld fo rm

within twelve hours .




Iron, other Foreign Metals; Salts of Magnesium an

Alkalies. —

(a) Dissolve 1 gm. of manganous chloride in 15 c

water, add 1 cc. of hydrochloric acid, 3 cc. of

r ine water , and he at to boiling. The solution ,

cold, should not acquire a red color on the ad

of potassium sulphocyanate solution, nor shoulchange appe ar on the addition of an exce


(6) Precipitate the manganese from a solution of

of man gano us chloride in 50 cc. of wa ter b y a

amm onium carbon ate solution (5 gm. of am mo

carbonate in 50 cc . of water ) . F i l ter , eva

the f iltrate, an d ign ite the residue. I t sho ulweigh more than 0.001 gm.




lized ferrous su lph ate a nd 100 cc. of pu re, co nce ntra ted

su lp hu ric acid in .1000 p a rt s of w ate r.* Close th e flask w ith

the s topper bear ing the l iunsen va lve , and heat unt i l the

manganese dioxide i s comple te ly decomposed, leaving no

dark-co lored residue . Th en cool , mak ing sure th e va lv e i s

closed as indicated by the collapsing of the rubber tubing.When cold , d i lu te wi th 200 cc . of water , and t i t ra te wi th

semi-normal potassium permanganate unt i l the fa int red color

no longer disap pear s, b u t persists for half a m inu te (fu rther

deeolor iza t ion i s neglec ted) . From the qu ant i ty of perm an-

ga na te corre spon ding by calcu lat ion to the 75 cc. of ferrous

su lph ate solution i s now deducted the qua nt i ty of per-

m an ga na te ac tua l ly used. Each cubic cent imeter of the




in 20 cc. of water should be perfectly clear, and should af

no immediate react ion on the addit ion of 2 cc. of ammon

oxalate solution.*

MERCURYHg. Atomic Wt. 200.

A l iquid m etal with a si lvery surface; com pletely

atil ized by heat, without leaving a residue.

TESTS OF PURITY

Foreign M etals. —

(a) On heat ing 20 gm. of mercury in a porcelain dish u n




drynes s on the wa te r -ba th . No weighab le r es idue shou ld

r e m a i n .

Arsenic . — Shake th e mercu ry sulphide obtaine d in abo ve

tes t wi th a mixture of 5 cc . of ammonia water and 45 cc . of

water , f i l ter , and acidulate the f i l trate with hydrochloric

acid. Ne ithe r a yellow color nor a yellow pr ec ipi tat e s hou lda p p e a r .

Mercurous Chloride and other Substances Insoluble in

Eth er . — 1 gm. of po wdered mercur ic chlor ide sh ould be

completely soluble in 25 cc. of ether .

MERCURY NITRATE

( M E R C U R O U S N I T R A T E )




TESTS OF PURITY

Non-volatile Matter . — On igniting 2 gm. of mercuric

no weighable residue should remain.

Chlorides. — Th e solu tion of 1 gm. of me rcu ric ox

5 cc. of nitric acid and 15 cc. of water should not be ren

more than slightly opalescent on adding silver nitrate so

Sulphates. — Th e so lution of 1 gm. of m ercuric ox

5 cc. of nitric acid and 15 cc. of w ate r should sho w no c

on the addition of barium nitrate solution.

Nitrates. — Dissolve 1 gm . of m ercuric oxide in 2

water and 2 cc. of sulphuric acid, and overlay this m

with 1 cc. of ferrous sulp hate solution. No colored

should form even on long standing.




this solution have a color, i t is to be decolorized before use

by heat ing wi th prev iously ign i ted an imal charcoal

METHYL ORANGE

(HOMUM SALT OF PAUAIHMimiYIAMlITOAZOBENZENEStTL-

raoNic AC ID)(01 Ia)B • N • OflI U • N: N • C0H4 • SOaNa. Mol. Wt. 327.24

An orange-yellow powder, easi ly soluble in w at er . As an

indicator, a solut ion of 0 .1 gin. in 100 cc. of water is used.


T o 100 cc. of dist i lled w ate r in a Je na f lask ad d 1 dro p of

the above me thyl o range so lu t ion . On add ing to th i s so lu-t ion one drop of decinormal hydrochloric acid7 t h e l i g h t -




NITRON

FOR THE GRAVIMETRIC DETERMINATION OF

NITRIC ACID

(1.4 D I P H E N Y L - 3 . 5 E N D A N I L O D I H Y D R O T R I A Z O L )

G20H10N4. Mol. Wt. 312.28.

Shining, yellow leaflets , or am orp ho us pow der, melt in g a t




NITROSOBETANAPHTHOL

CioH0(NO)(OH). Mol. Wt. 173.10.

Orang e-brown crystals , melt ing at 109.5° C , insoluble in

cold water , very diff icultly soluble in boiling water , and

ve ry easily soluble in eth er, benzene, and hot alcohol. I t is

used pr incipal ly for the qual i tat ive and quanti tat ive separa-tion of nickel and cobalt.

PALLADIUM

Pd. Atomic Wt. 106.5

Palladium occurs in the form of foil and wire which in

appearance great ly resemble plat inum; also in the form ofpal ladium -sponge, a gra y spongy mass , and as pal la dium




an d th e fil trate treated with am mo nia water in excess . N o

coloration or precipitate should ensue.

NOTE. — Regarding the quantitative determination of palladium, seeFresenius, Anleitung zur quantitativen chemischen Analyse, 6 ed., 1,348, 4 81; Fresenius-Cohn, Quantitative Chemical Analysis, 1, 389.

PALLADIUM CHLORIDE

( P A L L A D O U S C H L O R I D E )

PdCl2. Mol. Wt. 177.4.

Dark-brown, deliquescent mass, easily soluble in water.

Regarding the quant i ta t ive de terminat ion see the note under

Pa l l ad ium.

PALLADIUM NITRATE

( P A L L A D O U S N I T R A T E )





Add 2 drops of the indicator solution to 100 cc. of disti l led

wa ter . On the add i t ion of 0.05 cc . of decino rma l pota ss iu m

carbonate , the l ight-brown color of the water should pass

into pink; on the fur ther addi t ion of 0.05 cc . of decinormal

hydrochloric acid, the color should change to a golden yel low.

PHENOLPHTHALEIN

C20Hi4O4. Mol. Wt. 318.11.

A white or yellowish-white powder, easily soluble in

alcohol , an d me l t ing betw een 250 and 253° C. Ph en olp h-

thalein is used as an indicator in the form of a solution of1 gm. in 100 cc. of neutral 95 per cent alcohol.




m atio n of monocl inic p la tes , mel t ing a t 23° C. Ph en y

drazine is but sl ightly soluble in cold water, but is

rea dily soluble in ho t wa ter, an d is easily soluble in alc

and in e ther .TEST OF PURITY

Solubil ity. — 2 cc. of phen ylh ydr azin e, w hen s hak en

20 cc. of 2 per cent acetic acid, should afford a clear solu

PHLOROGLUCIN

C6H3(OH)3 + 2H2O. Mol. W t. 162.08.

A w hite, or slightly yellowish, crystal l ine pow der, w

loses i ts wa ter of c rystal l izat ion at 100° C , and w hich

being rapidly hea ted, mel ts a t 217 to 219° C , b ut whwhen s lowly heated, mel ts a t a much lower tempera




wate r-ba th , and conver t the res idua l p la t inum chlor ide in to

pla t inu m sponge by s t rongly igni ting . On now t rea t ing the

sponge with nitric acid and filtering, the fil trate should not

leave more than t races of residue on being evaporated.

Si lver. — Dissolve plat inum in ni t rohydrochloric acid, evap-

ora te the so lu t ion to dryness on the wate r-ba th , and d issolvethe residu e in wa ter. No wh ite residue should rem ain .

NOTE. — Regarding the further testing of platinum for slight impu-rities, see the paper by F. Mylius and P. Foerster: "Uber die Herstellungund Beurteilung von reinem Platin," Ber., 25, 665 (1892); J. Chem. Soc,62, 789 (1892).

PLATINUM CHLORIDE

( P L A T I N I C C H L O R I D E ; C H L O R PL A T I NI C A C I D )




Sulphates. — The solu tion of 1 gm . of platin ic ch loride

20 cc. of water should give no precipitate of barium sulpha

on adding barium chloride solution, and setting aside thr

hours .

Nitrates. — On mixing 2 cc. of th e 1:10 solution w2 cc. of concentrated sulphuric acid, and overlaying th

mixture with 2 cc. of ferrous sulphate solution, no brownis

red zone should develop at the contact-surfaces of the tw

liquids, even on long standing.

Barium Salts. — The 1:2 0 solution of platinic chlori

should afford no precipitate of barium sulphate on addingfew drops of sulphuric acid, and allowing to stand thr




acid, the solut ion should not acquire a red color

wi th po tass ium su lphocyanate so lu t ion .

Ca lcium . -Dilute 10 cc. of potassium ac et ate solu tion

w ith 10 cc. of water , and a dd amm onium oxa late so lut ion.

No precipi tate of calcium oxalate should form on s tanding

th r ee h o u r s .POTASSIUM ANTIMONATE

( P OTA S S IUM A C ID PYR OANTIMO NATE * )

K,.H,ttb,t()7 \ 4 11,0. Mol. Wt. 504.78.

A white, granular , crystal l ine powder , d if f icul t ly soluble

in cold water (1 :250) , and more readi ly soluble in boi l ing

w a te r ( 1 :1 )0 ) . TKSTS OK PURITY



152 CHEMICAL itNAdNNTS

TIOSTS OF PUIUTY

Sulphates. — On boil ing the solution of;{ gm. of po t

bica rbon ate in 50 ee. of wate r an d f> ee. of hy dro chlo r

for several minutes , and then adding bar ium ch lor ide so

no precip i ta te of bar ium su lpha te should form w i th in

hours .

Chlorides. — Dissolve t t gm . of potassium bi ca rb on

50 cc. of wate r, add 10 ee. of nitric, acid an d so m e

nit ra te solution. More tha n a sl ight opalcsconec sho u

develop .

Nitrates. — Dissolve !i gm . of potassium bic ar bo n

20 cc. of wate r an d 10 cc. of 10 per ce nt sulphuric* a c

add ing to the solution 1 dro p of a 1: 1000 indigo sand 10 cc. of con cen trate d sulp huric acid, the blu e



CllIUIICA L REAGE NTS 153

Iron, Dissolve 1 ^m . of potass ium bica rbon ate in 3 cc .

of hyd roch loric acid and 10 cc. of wa ter , ad d a dr op of nitr ic

acid and boi l , then add potass ium sulphocyanate solut ion.

No red color should develop.

Residu e on Igni t ion. 100 pa r ts of potass ium bicar bo na te ,

on ign itio n, shou ld leave (>() p ar ts of residue .

Quant i ta t ive Dete rmina t ion . On t i t r a t ing 1 gm. of po tas -

s ium bicarbonate with normal hydrochlor ic acid, us ing methyl

or an ge as indic ator , 10 cc. of acid should be re qu ired.

1 cc. of no rm al H(H 0.10015 gm . of KIIC O a , log. 000G5.

POTASSIUM BINIODATE

KK> ;1-HIO;,. Mol. Wt. MO.OO.



!54 CHEMICAL MMMNTX

with 100 cc. of water, anil t itrate tin*

iodine with decinormal .sodium thiosulphate

lcc.of decinormalNa2SA «0.(KW25()7«ni.<»f KK

log. 51199.

Potassium biniodatc may also be tested as to the

ness of its composition by comparing the iodine fo

with the quantity of iodine liberated from potassiu

date by potassium iodide without the addition of an

As will be seen from the equation* given Mow

potassium biniodate is decomposed by potassium

without the addition of an acid, it liberates exac

twelfth of the quantity of iodine which is liberate

same quantity of potassium biniodate is decompo

potassium iodide in the presence of hydrochloric or s

acid.




1. 5KHI2O6 + 5KI « IOKIO3 4- 5HI;2. KHIoOo + 5HI = KIO 3 + 61 + 3H2O; hence3. 6KHI2O0 + 5KI = IIKIO3 + 61 + 3H2O.One KHIoOe, therefore, liberates one I.In the presence of an acid, the reaction is as follows:KHIoOo + 10KI + 11HC1 = 11KC1 + 6H 2O + 121.

Here, therefore, one KHI2O6 liberates twelve I.POTASSIUM BISULPHATE

( P O T A S S I U M A C I D S U L P H A T E )

KHSO4. Mol. Wt. 136.21.

Colorless crysta ls , soluble in 2 pa r ts of wa ter . Th e aq ueo us

solu t ion i s ac id to l i tmus paper .

TESTS OF PURITY




TESTS OF PURITY

Heavy Metals and Arsenic. — Ev apo rate to d r y urns

sand-bath a mixture of 5 gm. of potass ium b is u lp h i t

5 cc. of sulphuric acid ( sp. gr. l.cS4), and dissolve* t h e r

in 20 cc. of water. 10 cc. of this solution sh o u ld sh o

change on the addi t ion of hydrogen sulphid e w at eradding to the other 10 cc. of the potassium su lp h a te so

a solut ion of ammo nium mo lybdate in ni t r ic acid , nn d h

the mixture to 70 to 80° C, the l iquid should not . acq

yellow color, nor should a yellow prec ipit ate form .

Quanti tative Determination. — Dissolve 1 gm. o f po ta

bisulphite in boiled wa ter and dilu te to 100 cc . Allo

solution to run from a bur ette into a m ixtu re of .'10 decinormal iodine solution and 5 cc. of hy dr o ch lo ric




Sulpha tes . — Dissolve 1 gm; of p otassium bi ta r t r a te in

20 cc. of water , add 5.0 cc. of ni tr ic acid and barium nitrate

solut ion. No precip i ta te should form within twelve hou rs .

Am mo nium Compounds . — On hea t ing 2 gm. of po tass ium

bi tar t ra te wi th 10 cc . of sodium hydroxide solut ion no vaporsof ammonia should be evolved ( to be ascer ta ined by moist

l i t m u s p ap e r ) .

Calcium. — Dissolve 1 gm. of potassium bi tar t ra te in 5 cc .

of di luted acetic acid and 25 cc. of water , with the aid of

he at . Allow to bec om e perfe ctly cold, filter, an d to th e

fil trate ad d a few dro ps of am m on ium ox alate so lution.

The l iquid should show no turbidi ty wi thin ten minutes .



158 CHEMICAL K ttAaNNTS

POTASSIUM BROMATE

KHrOa. Mol. Wt. 107.11.

Colorless crystals or crystalline powder, soluble hi 15

of cold, or 2 parts of boi l ing, wa ter . Th e prep arat io n

tains 100 per cent of KBrO.,.

TRSTK OK PURITY

Potassium Bromide. Dissolve4 2 grn. of potassium

rnate in 20 cc. of wa ter and ad d 5 ce. of dil ute su lph uric

The solut ion should not immediately acquire a yel low c

Quantitative Determination. For this purposes the

mu st be dr ied over sulp huric acid for twen ty-four h

Then dissolve 0.10 to 0.15 gin. of the dr ied potass ium br o

in 20 cc. of water, add 3 gm. of potassium iodide, 5 c



CUKMICAIJ R1M0ENT& 159

20 ec. portions of the 1:20 solution should show no change

by hydrogen sulphide water nor by barium ni t ra te solut ion,

nor by di lute sulphuric acid.

Iod ides . Add 2 or .'{ dr op s of ferric chlo ride sol utio n to

20 CT. of the 1:20 solutio n, then ad d 5 ee. of chloroform and

shakes Th e latter should no t acqu ire a violet color.

Exc ess of Potas sium Chloride.* On add ing a few dro ps of

po tass iu m el imin ate solut ion to 10 cc . of the aqueo us solu-

tion, prepared from 3 gm. of potassium bromide, dried at

100° 0. , and dissolved in 100 ec. of water, the solution should

not require more than 25.4 ee . of decinormal s i lver ni t ra te

solu tion to produce* a pe rm an en t red color.



260 CHEMICAL HKAUUNTS

Solution with hydrochloric acid, them boiling (or a IVw u t

and adding barium chloride .solution, no pre cip itate of b

sulphate should form within twelve hours.

Nitrates. — Dissolve 0.2 gin. of potassium c a rb o n a

2 cc. of dilute sulphuric acid, and mix the fluid with %J

conce ntrated suphuric acid. On now cooling the .so

and overlaying it with 1 cc. of a ferrous su lph ate so lno reddish-brown zone should form at the contact -su

of the two liquids.

Potassium Cyanide. — Dissolve 0.5 gm. of fer rous .su

in 5c c. o f water, add 5 cc . of a 5 perc en t po tass ium c ar b

solution, and 1 or 2 drops of ferric chloride sol utio n,

to about 60 to 70° C. ; and acidulate with hydrochloric

No green color should develop, nor should a b lur piv ciform.



VlttitolCAL HUM!UNTS 101

form, nor should any change take place on the addit ion of

ammonium oxulate solution to the sl ightly alkaline l iquid.

Qu anti tat ive Dete rmina tion. Dissolve 1 gin. of pota ssium

ca rb on at e in f>() e<\ of wa ter, ad d I dro p of m eth yl ora ng e

solution, and t i t ra te with normal hydrochloric, acid. A t

least t I.;i ec. of the h ydro chlo ric acid should be re qu ire d to

produce the red end point .

1 cc . of norm al UC1 0.0(><>ir> gm . of K 20( ) a, log. 83979.

POTASSIUM CARBONATE SOLUTION

A clear, colorless, alkaline liquid, of specific g ra vi ty 1.330

to L.'t.'M. 100 pa rt s co nta in abo ut X\ par ts o f po tass ium

carb o n a te .TUSTS OK PURITY



162 CHEMICAL RK AOENTH

Nitrates. — O n heat ing 1 g in . of potass ium ch lo ra te

5 cc. of sodium hydroxide solution (up. gr. 1.3), and u

ture of 0.5 gm. of zinc du st an d 0.5 Rin. of pow de red iro

ammonia should be evolved ( to be ascertained by

l itmus paper ) .

Sulphates. — On adding bar ium chloride solu t ion to

of the 1:20 aqueous solut ion, no precipi tate of bar iumphate should form on standing twelve hours .

Arsenic. — Po ur 100 cc. of hydrochloric acid o ve r 2

of potassium chlorate in a capacious porcelain dis h. AH

as the evolution of chlorine has s lackened, ev ap or a t

solu ti on on t he w a t e r - ba t h t o d r y m m A Mar sh a p p

is set in operat ion, containing 20 gm. of arsenic-free,

l a ted z inc and d i lu te (1 :5 ) su lphur ic ac id . T he r



CHEMICAL HE AGENTS 16 3

POTASSIUM CHROMATE

( Y I O L U ) W P O T A S S I U M C H I I O MA T K )

K,CrO4. Mol. Wt. 194.4.

Yellow, rhombic crystals, permanent in the air , soluble in

2 pa rts of cold wa ter, bu t insoluble in alco ho l Th e 1:20

aqueous solut ion i s s l ight ly a lka l ine to l i tmus paper .

TKHTH OK PURITY

Free Alkali. ---The solution of 0.1 gm. of potassium ehro-

mate in 25 ee. of water should not acquire a red color on

the addit ion of a few drops of phenolphthalein solution.

Sulphates. Dissolve li gm. of potassium ehromate in 100

cc. of water, and add 30 ee. of hydrochloric acid, followed by



IQ4: ClitiMICAL ItEAGEN TS

POTASSIUM CYANIDE

KCN. Mol. VVt, (>r>.l<).

A white powder, easily .soluble in 2 part s of w a te r ,

readi ly in boil ing 65 per cent a lc oh ol . The aq ue ou s so lu

is alkaline to li tmus pap er. T h e salt con tai ns 0 0 t o

per cent of KCN.

TICSTtf OK .PURITY

Sulphides. — On adding a so lu tio n of lead a ee fa te to

solution of 1 gin. of pota ssium cy ani de in 20 c c of w a

the resulting precipitate should have a pure white* color .

Carbonates , Sulphocyanates, a n d Fer rocyanid es . On

ing 5 cc. of hydrochloric acid t o the solution of 1 p n

potassium cyanide in 20 cc . of water , — which sho uld done under a 'hood with a good d ra f t ,— only a s l ig ht e



CHKMK'AL IWMit iNTX 165

insoluble in a lcohol. The aqueous solution reddens blue

l i tmus paper .

TKSTS OK PURITY

Sulp hates. Dissolve •{ gm . of potassium dieh rom ate in

IOC) c c of w ater, and ad d HO e c of hydroch loric acid followedby bar ium chlor ide solution . No precip ita te of bar ium sul-

phate should form on standing twelve hours.

Ch lorides. Dissolve* 1 gin. of potass ium dich ro m ate in

20 ec. of wa ter, ad d 10 ec. of nitric acid, and h eat the m ix-

tun* to abo ut 50° ( \ On now add ing a few dro ps of s i lver

nitra te solution, no turbidity should develop nor should a

prec ip i ta te furm ;\vi thiu l ive minutes.




TESTS OF PURITY

Ferrous Salt. — On first rem ovin g the superficial lay e

a crysta l by washing with water, and then preparing

per cent aqueous solution from the washed crysta ls ,solution m ust n ot acqu ire a blue color on the add itio n

few drops of a dilute ferric chloride solution.

Sulphates. — On ad din g 1 cc. of hydroch loric acid to 2

of the 1:20 aq ue ou s solution, and the n adding ba

ehloride solution, no precipita te of barium sulphate sh

form on s tanding twelve hours .




TESTS OF PURITY

Carbonates. — On t rea t in g 1 gm. of powdered pota s s ium

ferrocyanide with di lute sulphuric acid, there should be no

evolution of gas.

Sulphates . — Dissolve 1 gm . of po tass ium ferrocyan ide in

20 cc. of water, and add 1 cc. of hydrochloric acid followedby bar ium chlor ide so lu tion . No imm edia te turb id i ty shou ld

ensue.

Chlorides. — Deflagrate a mix tu re of 0.5 gm . of po w de red

potass ium ferrocyanide and 1 gm . of potass ii ftn n i t r a te ,* b y

introducing smal l quant i t ies a t a t ime into a porcelain cru-

cible hea ted to redness . Tr ea t the res idue with 20 cc . of

w at er , filter, an d to th e filtrate a dd 3 cc. of nit ric acid an d



168 CHEMICAL HEMWSTX

I

POTASSIUM HYDROXIDE, PUREST

White pieces allowing a crystall ine s t ructu re on fra ctu re ,

The preparat ion contains 82 to SF> per cen t of KOI I.

TKSTS o r IH'IUTYSulphates. — Dissolve H gin. of potassium hydroxide* in

50 cc. of wa ter, add 10 ee. of hydro chloric a cid, h ea t to

boiling, and then add barium chloride 1 solu tion . No prec ip i -

tate of bar ium*sulphateshould form on standing twelve hours .

Chlorides. -- Dissolve\ 1 gm . of potassium h yd ro xi de in

20 cc. of water, and add !> cc . of nitric acid, followed hy a

few drops of silver ni tra te so lutio n. Not more th an a Nlijchtopalescent turbidi ty should develop within one minute.



CHEMICAL REAGENTS

Phosphoric Acid. — Disso lve 5 gm. of po tass ium

in 50 cc. of water and add 50 cc. of nitric acid,

25 cc . of a solut ion of ammonium molybdate in This mix ture should depos i t no ye l low prec ip i ta te

two hour s a t abou t 40° C .

Silica. — Dissolve 5 gm . of po tass ium h ydro xid

of water in a pla t inum dish, add 25 cc . of hydroc

an d th en eva po ra te to dryn ess on the w ater -ba th



170 CHEMICAL HHAaUSTS

Quanti ta t ive Determinat ion, and Determina t ion of th e

Potass ium Carbonate Content .— Tilnt l r a cold solut ion uf

1 gin. of potassium hyd roxid e in 100 n \ of wa frr with nor nm J

hydrochlor ic acid , uxing phenoIphMmlrin us thr iwlini tnr .

At least 14.«S cc. of tho acid should bo uocosunry f n d i v f m v

the red color . (F irs t (R ral ion. ) Now add I dr op of nir fh yloran ge, an d titrate? further unti l the* color aga in vUntitfo* '«»

red. I n this second titration , no t more than 0.1**5 c<\ of tin*

acid should be required (2.07 per cent K,( '<). , ) .*

1 c c. of no rm al 1101 - ().()/>« 1/5 #m . of K ( ) H , log. 7J ( j ;M

1 cc. of norm al IIC1 - 0.00915 #, ». <>f '<, ( '( ) ,, lo/?. SM7\K

II

POTASSIUM HYDROXIDE, PU RIFIE D BY ALCOHO L



CHEMICAL RUAUKNTli 171

an d eva po rate to dry ness on the wate r-hath . Dry the res idue

lor hall ' an hour on the sand-bath at about 120° 0. , then

tr ea t it with 10 c c of hydroch loric, acid and 00 ec, of wa ter ,

fi lter, wash, and ignite any undissolved residue. Th e weigh t

of the latter should not exceed 0.0025 gin.

Alu min a, Calcium, and Heav y Metals . 5 gm. of potass iu mhydroxide should completely dissolve in 20 cc. of water,

affording a clear and colorless solution. Dilute the solutio n

to 100 cc, and add 25 cc, of acetic acid (sp. gr. 1.041) followed

by 10 ce. of am m on ia water* At most a sl ight tur bid ity , bu t

no f locculent precipi ta te of a luminum hydroxide should de-

velo p w ithin five* m inu tes; and no imm ediate chang e shou ld

appear on the addi t ion of ammonium oxa la te and ammonium




1 drop of 1:1000 indigo solution, a granule of sodium chlo

r ide , an d 10 cc. of con cen trated sulp huric acid. Th e blue

color of the mixture should not disappear wi thin ten minutes

Alumina, Calcium, and Heavy Metals. — 2.5 gm. of p ot as

sium hydroxide should completely dissolve in 10 cc. of wateryieldin g a clear an d colorless solu tion . Dilu te the so lution to

100 cc. and add 15 cc. of acetic acid (sp. gr. 1.041), followed

by 10 cc. of ammonia water; a sl ight turbidity may form

within f ive minutes, but no f locculent precipitate of alumi

num hydroxide should develop. The solut ion so tested

fi l tered if necessary, should not exhibit an immediate tur




POTASSIUM IODATE

KIO 3. Mol. W t. 214.12.

A wh ite, crystalline pow der, soluble in 13 pa rts of cold,

an d in 3 par ts of boi ling, wa ter . The aqueou s solut ion

should be clear and have no acid react ion. The prep ara t ion

contains 100 per cent of KIO 3 .

TESTS OF PURITY

Free Acid. — Dissolve abo ut 0 .5 gm. of potass iu m iod ate

in about 20 cc. of boiled water , and add a small crystal of

neutral potass ium iodide and a few drops of f reshly prepared

starc h solut ion. Th e l iquid should not imm ediately ac quirea blue color.




TESTS OF PURITY

Potassium Carbonate. — Potas s ium iodide when crushe

and placed upon moistened red l i tmus paper should no

immediately color the latter violet-blue.

On adding to a solution of 0.5 gm. of potassium iodide i10 cc. of w ater 1 dro p of phe nolp htha lein so lution , no re

color should develop.

M etals and Sulphates. — 20 cc. portions of the 1:2 0 aqu eou

solution should afford no reaction with either hydroge

sulphide water or barium chloride solution.

Cyanides. — On add ing to 20 cc. of the 1:2 0 aqu eou




POTASSIUM IODIDE, NEUTRAL

TESTS OF PURITY

Neutrality. — Dissolve 10 gm . of the ne utra l po tass ium

iodid e in 50 cc. of w ate r, in a stoppe red, flint-glass b ot tle ,overlay with 30 cc. of ether , and add 3 drops of iodeosin

solution . After vigorously shaking , the aqueo us laye r will

exhibit a pale-red color which disappears on adding 1 drop

of decinormal hydrochlor ic acid and thoroughly shaking.

Should the water which has been used for making the

solution of potassium iodide have an alkaline reaction to

iodeosin, i t must be f irs t rendered neutral to i t .




Calcium and Heavy Metals. —

(a) The solution of 3 gm. of potassium nitrate in 50

of water should not be affected by hydrogen sulph

water .

(b ) The solution of 3 gm. of potassium nitrate in 50

of water should not be affected by ammonia wat

nor by the further addition of ammonium oxalsolution and of ammonium sulphide solution.

Iron. — 20 cc. of the 1:20 aque ous solution, acid ulat

with 1 cc. of hydrochloric acid (sp. gr. 1.124), should not

reddened by potassium sulphocyanate solution.

Nitrites. — Dissolve 1 gm. of potassiu m n itr ate in 20

of water, acidulate with 1 cc. of 16 per cent sulphuric ac

an d a d d 1 cc. of a freshly pre pa red , colorless 1: 200 s olutiof metaphenylenediamine hydrochloride.* No yellow



CltblMlCAL REAGENTS 17 7

Qu ant i ta t ive Determ inat ion. -D isso lve 10 gin . of po tas -

sium nil r i te in water and dilu te to 1000 cc. M ake a mi xt ur e

of 50 <•<». of de rin or m al po tass ium pe rm an ga na te ( ac cu rat ely

measured) with :«H) e<\ of water and 25 cc. of 10 per cent

su lph uric acid, wa rm to <10 to 50° (.!, and , while co ns tan tly

•shaking, al low the ni tr i te solution to run slowly into i t , unti l

t he red co lo r d i sappea rs . Ca re mus t be t ak en ' tow ard s the

end to run in the ni tr i te solution very slowly, because the

cha ng e from red to colorless requires some t ime . N ot mo re

than 23.7 ee. of the potassium nitr i te solution should be

requ i red .

1 ( T , of dec inorma l KM n( ) 4 - 0.0042595 gin. of KN0 2 ,

log. iYJAVMl




Quantitative Determination. — Dissolve abo ut 3.2 gm . o

po tas siu m oxa late in wa ter and dilute to 500 cc. To 50 c

of this solution add 6 to 8 cc. of concentrated sulphuric acid

hea t th e liqu id to abo ut 60° C , and t i t ra te with decinorm

po tass ium pe rmangana te .1 cc. of decinormal KMnO 4 - 0.0092158 gm . of K 2C aO 4

H 2O , log. 96453.

POTASSIUM PERCHLORATE

KCIO*. Mol. Wt. 138.6.

Colorless, rho m bic prisms,* soluble in ab ou t 65 p ar ts o




P O T A S S I U M P E R M A N G A N A T E

KM11O4. Mol. Wt. 158.15.

I

POTASSIUM PERMANGANATE

Dark-violet , a lmos t b lack pr isms , exhibi t ing a s teel-b lue

luster, soluble in 16 parts of cold, and in 3 parts of boiling,

w a t e r . T h e 1:1000 aqueo us solution is neu tral to l i tm us

p a p e r .

TESTS OF PURITY




dissolve 6.715 gm. of sodium oxalate,* dried at 240° C. (see

Sodium Oxalate, Sorensen 's ) , in water and dilute to 1 l i ter

( decino rma l sodium oxa late ) . M easure off 30 cc. of t he

oxalate solution with a burette , add to i t 6 to 8 cc. of concen-

tra te d sulphuric acid, he at to a bo ut 60° C. ,and run in th e

potass ium permanganate so lu t ion unt i l a permanent red co lor

appea rs .

1 cc. of decinormal Na2C 2O 4 = 0.003164 gm. of KMnO 4 ,

log. 50024.

I I

POTASSIUM PERMANGANATE, FREE FROMSULPHATES



CHEMICAL liUAUENTS 18 1

TIOT OK PURITY

Quant i t a t ive Determination. • I )issolve 1 gin. of p o ta s-

Hium sta nn os ul ph ate in a solution of 5 gm. of Hodiiun b icar-

bo na te and f> gin. of potassium and sodium t ar tra te in 100 cc.

of wa ter, a nd t i tr ate the* clear l iquid with deeino rm ai iod ine,

using starch solution as the indicator.

I cc. of de ein or m ai I 0.019-171 gin. of K 2Sn(SO 4 ) 2 ; log.

2HMI).

POTASSIUM SULPHATE

K,SO*. Mol. Wt. 174.30.

W hit e, ha rd crys tals , soluble in 10 pa rts of cold, an d in

-1 p ar ts of boiling, wa ter, b ut insoluble in alcohol. T he

aqueous solut ion is neutral to l i tmus paper .




TEST OF PURITY

Nitrogen. — Mix 100 cc. of the potassium sulphide soluti

in a distilling flask with 50 cc. of nitrogen-free sodium h

dr ox ide solution ( sp. gr. 1.3). Ad d 1 gin. of zinc du st, a

disti l off about 50 cc, collecting the disti l late in a U-tu

receiver containing about 20 cc. of water and 2 to 3 cc. dec inorm al hydro chloric acid. Ti tra te the disti l late w

decinormal potass ium hydroxide, us ing methyl orange as t

indica tor . The amm onia dis t il led over should not hav e ne

tralized more than 0.2 cc. of the decinormal acid.

POTASSIUM SULPHOCYANATE

( P O T A S S I U M T H I O CY A N A T E )



('IIVMICA /, UK A (IKN TS 183

POTASSIUM SULPHYDRATE

( P O TA S S IU M I IY O K O H U LP H ID K )

•JKSII ! II ,( ) . Mcil. VVt, K;2.'I5.

(olorkss, deliquescent crystals* cîsily .soluble in water and

in a lcohol . Th e solution is s t rongly a lkal ine to l i tmu s pa per .

<>n Ixiilintf, the aqueous solut ion is decomposed with theevolution of hydrogen .sulphide gas and the formation of

potas s ium hydroxide .

TKST OF IHIIUTV

Poly sulp hlde a. The* solu tion of 1 grn. of po tas siu m sul-

phydrafo in 'JO cv . of water should be colorless and clear .

On acidulat ing the solut ion with hydrochlor ic acid, hydrogensulph ide p is is generated in copious quan t i t ies , and th e f luid




1 cc. of f if th normal KOH = 0.016947 gm. of KHC 2O

H 2C 2O 4 + 2H 2O, log. 22909.

(b ) Oxidimetric: To 50 cc. of the solution made for tes

add 6 to 8 cc. of concentrated sulphuric acid,

the l iquid to about 60° C , and t i t r a te wi th dec inor

po ta ss ium pe rmangana te .

1 cc. of decinormal KMnO 4 = 0.006355 gm. of KHC 2OH 2C 2O 4 + 2H 2O, log. 80312.

POTASSIUM AND SODIUM TARTRATE

( R O C H E L L E S A L T ; S E I G N E T T E S A L T )

KNaCJHUQo + 4H2O. Mol. Wt. 282.29.

Colorless, prismatic crystals, soluble in 1.4 parts of wa

and yielding a neutral solution.



CHEMICAL HKAUKNTti 185

PYROGALLOL

( A CI D P Y I U K J A L U C)

<\»IUOII)a. Mol. Wt. V2(\M.

While , sh in ing IUM»C11<»S or scales, melting at 131° C. Py ro -

gullol is solu ble in 1.7 pa rt s of wate r, in 1 p ar t of alco ho l,

an d in 1.2 p ar ts of et he r; it is difficultly soluble in be nze ne ,chloroform , and carbon disulphide. The aqueous solut ion is

s l ight ly acid to l i tmus paper .

T10KTS OK PURITY

Ino rga nic Mat ter . 1 gm . of pyrogallol, on being he ated ,

should volati l ize and leave no weighable residue.

Gallic Acid. 2 gin. of pyrog allol m ust com pletely disso lve




solution, a wine-red l iquid is obtained, which, on the add

of 1 drop of decinormal potassium hydroxide, should ass

a blue color.

SILVER

Ag. Atom. Wt. 107.93.

A white, shining metal in the form of foil, insolublhydrochloric and in cold dilute sulphuric acids; soluble

ni t r ic and in hot concentra ted sulphuric ac ids .

TESTS OF PURITY

Fo reig n M etals. — Dissolve 2 gm. of silver in the sm a

possible qu an tity of nitric acid ( sp. gr. 1.2) . Th e solu

should be colorless and there should be no insoluble res




wi th 0.6 p ar t of water, a nd w ith abo ut 10 pa rts of a lcohol .

The aqueous solut ion should be neutral to l i tmus paper.

TESTS OF PURITY

Chlorides. — Dissolve 5 g m . of silver ni tr at e in 5 ce. of

water, and allow the solution to run into 100 cc. of water.No turbidi ty or opalescence should occur.

Potassium Nitrate. — Dissolve 0.5 gm. of silver n itr at e in

0.5 cc. of water, mix the solution with 20 cc. of absolute

alcohol , and shake for a few minu tes. No tur bid i ty or

precipi ta te should form.

Salts of Copper, Bismuth, and Lead. — Dissolve 1 gm . of

silver nitrate in 5 cc. of water, and add to the solution 10 cc.




ha s settl ed, filter, and evap or ate the filtrate to dry nes s. N

weighable residue should remain.

Quantitative Determination.* — Disso lve 1.5 gm . of silv

nit ri te in wate r and dilute to 500 cc. Make a m ixt u

containing 18 to 19 cc. of decinormal potassium permangana

solution, 20 cc. of dilute sulphuric acid, and 300 cc. of wate

he at i t to 40 to 50° C , an d run th e nitri te solution into un til the pink color just disappears . Care m ust be take

towards the end to introduce the nitri te solution very s lowl

because the change from pink to colorless always requir

s ome t ime .

1 cc. of decinormal KMnO 4 = 0.0076985 gm. of AgNO

log. 88640.

SODIUM




SODIUM ACETATE

NaC2H3O2 + 3H2O. Mol. Wt. 136.12.

Colorless, t ransparent crystals, eff lorescent in warm air ,

soluble in 1 part of water , in 23 parts of cold, and 1 part of

boil ing, alcohol.

The solution of 1 gm. of sodium acetate in 1 cc. of water

is a lka l ine to l i tmus paper ; i t should, however , not be red-

dened, or only very sl ight ly, by phenolphthale in solut ion.

TESTS OF PURITY




SODIUM BICARBONATE

NaHCO3. Mol. Wt. 84 .05.

W hi te, crystalline cru sts , or crystalline powder, soluble

12 pa rts of wate r , bu t insoluble in alcohol. The a que ou

solution is faintly alkaline to li tmus paper.

TESTS OF PURITYSulphates. — Dissolve 2 gin. of sodium bicarbonate in 30 c

of water , add 10 pc. of hydrochloric acid, heat to boilin

and add bar iu m chloride solut ion. No precipi ta te of bar iu

sulphate should form within twelve hours .

Silica. — Dissolve 5 gm. of sodium bicarb onate in 15 c

of water and 25 cc. of hydrochloric acid in a platinum dis

Evaporate the solut ion on the water -bath, dry the res idu




(b ) Th e solution of 1 gm . of sodium b icarb ona te in 15 cc.

of w ate r and 2 cc. of hydroch loric acid should no t

be reddened on the addi t ion of potass ium sulpho-

cyanate solut ion.

Potassium. — The yel low color imp arted by sodium bicar-bonate to the flame, when observed through cobalt glass,

should have at most a t ransient viole t t inge.

Monocarbonate (Neutral Sodium Carbonate). —

(a) A solution of 1 gm . of sodium bica rbon ate in 20 cc. of

water , prepared at a temperature not above 15° C,

without excess ive shaking, should not be imme-




SODIUM BISULPHATE

( S O D IU M A C I D S U L P H A T E )

NaHSO4 + H2O. Mol. Wt. 138.13.

Colorless crystals, or white, fused pieces, easily soluble

w ater . Th e aqueous solution is s trongly acid to l i tm us pap

TESTS OF PURITY

Heavy Metals. — Th e solution of 1 gm. of sodium bis

ph at e in 20 cc. of w ater should not be affected by hyd rog

sulphide water ; nor should i t show any change on making

alka l ine wi th ammonia water , and then adding ammoni

sulphide solut ion.

Chlorides. — 20 cc. of the 1:2 0 aqueo us solution shonot be rendered turbid on adding s ilver nitrate solution.




TESTS OF PURITY

He avy M etals and Arsenic . — Completely evapo rate a m ix -

tur e of 5 gm. of sodium bisu lphi te w ith 5 cc . of pure sulp hur ic

acid (sp. gr. 1.84) on the sand-bath, and dissolve the residue

in 20 cc. of w ate r. 10 cc. of this solution should no t b e

affected by hyd rog en sulph ide water . On addin g to th eothe r 10 cc . of the solut ion a solut ion of amm oniu m m ol yb da te

in ni t r ic acid, and heat ing the mixture to 70 to 80° C, the

liquid should not acquire a yellow color, nor should a yellow

prec ip i ta te form.

Qu anti ta t ive Deter min at ion. — Dissolve 1 gm. of sodiu m

bisulphi te in thoroughly boi led water and di lute to 100 cc .



194 CHEMICAL I tKMiKSm

I

SODIUM BORATE

TKSTS OK PHUTY

Carbonates and Sulphates . The solution of 1 p;m. of l i o

in 20 cc. of water should not effervesce on t in* julditiun

hydrochlor ic add, and should not In* affected hy the ûl»

quent addi t ion of barium chloride solut ion.

Chlorides. — On adding to 20 cc. of the 1: U0 JUJUI-U

solut ion 3 cc. of nitric acid, followed hy silver nil r a t e .u

t ion, at most a slight opalescent turbidity .should «li*vr|np,

Quan ti tat ive Determination/11 Dissolve 1 yju. of \mvi\\

50 cc. of water , add 1 drop of methyl orange .sultiiicm. a

t i trate with fifth normal hydrochloric acid.




Ca lcium . — Th e solution of 1 gin. of bo rax in 20 cc. of

wa ter should no t be rendered tu rb id by amm onium oxala te

solut ion.

Iron and Other Metals. —

(a) T he solution of 1 .gm . of bora x in 20 cc. of w at er

should not be reddened on the addition of 2 cc. of

hydrochloric acid, followed by potassium sulpho-

cyanate solut ion.

(6) 20 cc. of the 1:20 aqueous solution, acidulated with

2 cc. of hydrochloric acid (sp. gr. 1.124), should

remain unchanged on the addi t ion of hydrogen

sulphide water .

Quant i tat ive Determinat ion. — The determinat ion is carr ied




SODIUM BORATE, PUREST, FUSED

( B O R A X G L A S S ; A N H Y D R O U S B O R A X )

Na2B4O7. Mol. Wt. 202.1.

Colorless, vitreous pieces, which take up moisture from

air , and in consequence become opaque.

TESTS OF PURITY

The tes ts to be made are those given under Sodium Bo

Pu res t, Cry st. Bu t for each gra m of the crystallized b

use 0.5 gm. of the fused.

Quanti ta t ive Determinat ion. — This is carr ied ou t as

scr ibed under Sodium Borate , Pures t , Calcined.

SODIUM BROMATE




S O D I U M C A R B O N A T E

SODIUM CARB ONATE, CRYSTALS

NaaCO3 + lOHoO. Mol. Wt. 286.26.

Colorless, transparent crystals, efflorescent in the air, sol-

ub le in 1.6 pa rt s of cold, an d 0.2 p ar t of boiling, w ate r. T he

aqu eou s solut ion is s t rongly a lkal ine to l i tmus pape r . Sod ium

ca rbo na te is insoluble in alcohol. Th e crystall ized so dium

carbonate contams 37 per cent of the anhydrous sal t , Na 2CO 3.

TESTS OF PURITY




eva por a te the so lu t ion on the wa ter-ba th to dryness . D

the residue half an hour at 120° C, and then dissolve it

3 cc. of hyd rochlo ric acid and 50 cc. of w ater . T he soluti

should be perfectly clear.

Nitr ates. — Dissolve 1 gm . of sodiu m carb ona te in 10

of dilute sulphuric acid, and overlay this liquid on 5 cc. of

solution of 0.5 gm. of diphenylamine in 100 cc. of conce

tr at ed sulphuric acid an d 20 cc. of wa ter. No blue co

should form at the contact-surfaces of the two liquids.

Pho spha tes. — To th e solution of 20 gm. of sodium carb

na te in 50 cc. of nitri c acid add 50 cc. of a solution of a

m on ium m olybd ate in nitr ic acid. No yellow pre cipita




water and 10 cc. of hydrochloric acid should not

acquire a red color on the addition of potassium

sulphocyanate solut ion.

Arsenic. — In tro du ce 2 0 gm . of arsenic-free, me tallic zinc

into the generating flask of a Marsh apparatus , and s tart the

hydrog en by adding di lu te sulphuric acid (1 : 5 ) . Dissolve

30 gm. of sodium carbonate in 100 cc. of dilute sulphuric

ac id (1 :5 ) , in t roduce the solut ion in smal l quant i t ies a t a

t ime in to the Marsh appara tus , and mainta in a s low s t ream

of gas for ab o ut half an ho ur . A t the close of this period no

deposit of arsenic should be vis ible within the reduction

t u b e .

Quantitative Determination. — Dissolve 3 gm . of sod ium

carbonate in 50 cc . of water , and t i t ra te wi th normal hydro-

chloric acid, using methyl orange as the indicator.



200 CHEMICAL REAUHSTX

I I I

SODIUM CARBONATE, ANHYDROUS

Na,(H>;t. Mol. Wt. I (Mi.I

A w hit e pow der, c onta ining 99 to MM) per cent nf N H /

TIOS'PS OK ITIUTV

Th e testa to bo ma de are those given under S od ium

bo na te Crysta ls. Hu t for each gram of cry sta ls use 0.JJ5

of the anhydrous .

Qu antitativ e De term inatio n. Dissolve I gin. in Aft n

water and titrate with normal hydrochloric arid, usiiiK ntf

ora nge as indica tor. At least 1S.7 re . of the u urm u!

should be re([uired.

1 cc . of no rm al HOI 0.0f>M

r

> gm. of Na,H >.,. lotf. 7U



(HIK MIV.Ah MUGUNTS 201

Alkaline Earths, and Heavy Metals. — The solution of 3 gm.

of sodium chloride in 50 ec. of water, heated to boiling,

should not. bo affected by ammonium oxalate solution; nor

by . sodium c arb on ate solut ion ; nor by amm onium sulphide

s o l u t i on .

M ag ne siu m . Dissolve ; j gm . of sodium chloride in 10 cc.

of wa ter , and ad d f> cc. of amm on ia water and a mm oniu m

ph os ph ate solut ion . No precip i ta te should form within three

h o u r s .

Iod ides . On addin g to 20 cc. of the 1:20 aqueous solu-

tion one drop of ferric chloride solution and some starch

solut ion, no blue color should develop.

Po tass ium . ( ) n adding platinic chlor ide solut ion and 3 cc .




TESTS OF PURITY

The tes t s and the quant i ta t ive de te rmina t ion as g i

under Sodium Chlor ide are to be made.

S O D I U M H Y D R O X I D E

(C A U S TIC S O D A ; S O D IU M H Y D R A TE)

NaOH. Mol. Wt. 40.058.

Three grades of sodium hydroxide are used in the chem

la bo r a to r y :

1. Sodium Hydroxide, f rom Sodium.

2. Sodium Hydroxide, Purif ied by Alcohol.

3. Sodium Hydroxide, Pur if ied.

These three preparations vary chiefly in their content




1: 1000 indigo solution, a granule of sodium chloride,

an d then 10 cc, of con cen trated sulphuric acid. Th e

blue color of tho mixture should not disappear

within ten minutes .

(//) Dissolve 25 gin. of sodium hydroxide in 100 cc. of

water in a distillation flask, and add 5 gm. of zinc

dust and 5 gm . of iron by hydroge n. Conn ect th e f lask

with a condenser and a U-tube receiver containing

l\ to 5 (•(•.. of fifth normal hydrochloric acid and 10 cc.

of wafer, allow to stand for several hours, and then

distil olT ab ou t 25 cc. over a small flame. T it ra te

the distil late with f if th normal potassium hydroxide,

using methyl orange as tho indicator . A t m ost




To 50 cc. add a few cubic centimeters of ammonium oxala

solu tion. No precip itate of calcium oxalate should form

s tanding two hours .

To another 50 cc. add a few drops of ammonium sulphi

solution; no change should appear.

Quantitative Determination and Determination of Sodiu

Carb onate Content. — Ti tra te t he solution of 1 gm. of sodiu

hy dro xid e in 100 cc. of wate r with n orm al hydrochloric ac

in the cold, using phen olph thalein as indicator. At lea

24 cc. of normal acid should be required to destroy the re

color. Now add 1 drop of me thy l orange, and t i trat e furth

un til the color changes to red. In th e second ti tra tion ,

most 0.3 cc. of acid should be used (3.18 per cent of Na 2CO 3)

1 cc. of norm al HC1 = 0.04005 gm. of NaOH , log. 60260

1 cc. of normal HC1 = 0.05305 gm. of Na 2C0 3, log. 7246




Nitrogen as Nitrates, Nitrites, Ammonia, etc. — Th e tes t is

car r ied out as detai led under Sodium Hy drox ide, Fro m

So d iu m .

Silica. — Dissolve 5 gm. of sodium hyd roxid e in 2 5 cc. of

water with 25 cc. of hydrochloric acid in a platinum dish,

and ev apora te to d ryness on the water -ba th . Dry the

residue on the sand-bath for half an hour at about 120° C,and then dissolve it in 10 cc. of hydrochloric acid and 90 cc.

of w at er . A ny insolub le resid ue is filtered off, wa she d, an d

ign ited . I t s weigh t after ignition should no t exceed 0.0025

g m .

Alumina, Calcium, and Heavy Metals. — 5 gm . of sod ium

hydroxide should afford a clear and colorless solution with

20 cc. of wa ter . Dilute the solut ion to 100 c c , and the n a dd



200 V U K M W A L K K A V K S T S

of Hodium chloride, and then 10 n \ of con cen trated sul ph u

acid. Th e blue color of tlie* m ixtu re .should not di sa pp

within ten minutes.

Al um ina, Calcium, and Hea vy Me tals. 2.5 jau, of M»d

hydroxide should afford a clear and eolorhw .solution w

JO ec. of wa ter. Dilute the solution to UN) ce. and ad d la

of acetic acid (sp. gr, 1.011) and 5 ec , of am mo nia w aAt most a slight turbidity should develop within fiv*• minut

bu t no f locks of aluminum hydro xide should se pa rate . T

solution th us tested should not im m edia tely 1«* ren de

tur bid on the* addition of am m oni um oxu late Molufion; a

on add ing to it. am mo nium su lphide solution, it should ac qu

at most a slight green color.

Quanti tat ive Determination and Determination of ihv S



MIKMICAL IWAGKNTi* 207

S O D I U M H Y R O X I D E S O L U T I O N S

( ( •A U H TH! S O D A S O U J TIO N H )

I

SODIUM HYDROXIDE, SOLUTION I—FREE FROM

NITROGEN

A rolnr!i»ss lie|tti< 1 of specific gravity 1.3, and containing

ab ou t 27 JUT cent of sodium hydroxide, N aOH .

T K N T S O F P U K I T V

Nitrogen of Nitrates, Nitrites, Ammonia, etc. — The tes t for

nit rog en in carr ied out by the distil lation meth od as described




TESTS OF PURITY

Th e tes t s to be m ade are those g iven under Sodium H y

dr ox ide , Purified by Alcohol. B ut for each gram of sodiu m

hy dr ox ide , purified by alcohol, use 5.6 cc. (6.5 gin.) o

sodium hydroxide , so lu t ion I I I .

S O D I U M H Y D R O X I D E W I T H L I M

( S O D A - L I M E )

I




II

SODIUM HYDROXIDE WITH LIME FROM ICELAND

SPAR

A white , porous, granular mass.

TESTS OF PURITY

Chlorides. — Dissolv e 5 gm . of sod a-lime in 50 c c. of

nitr ic acid ; and dilute the solution with 100 cc. of water.

Th e liquid should acqu ire a t most a slight opalescent tu r-

bidity on the addition of silver nitrate solution.

Ph os ph oru s. — Dissolve 10 gm . of soda-lime in 100 cc. of

nitric acid, and add to the solution 25 cc. of a solution of

am m on ium m olyb date in ni tr ic acid. No yelloyv precip ita te




Chlorides. — Th e solution of 1 gm . of sodium n itr at20 cc. of water, acidulated with a few drops of nitric a

should not be rendered turbid on the addi t ion of s i lver n i t

solut ion.

Chlorates and Perchlorates. — On g ently ignit ing 1 gm

sodium nitrate, dissolving the residue in 20 cc. of wa

and adding 1 cc. of nitric acid, the solution should not

rendered turbid on adding s i lver n i t ra te solut ion.Calcium and Heavy Metals. —

(a) The solution of 3 gm. of sodium nitrate in 50 cc.

water should show no change on the addition


(&) T he solution of 3 gm . of sod ium nitr ate in 50

of water should not be changed in appearance

the ad di t ion of amm onia w ater nor by add



CUKMWAh REAGENTS 211

(/*) Dissolve \\ gm. of sodium nitrate with the aid of heat

in <> c c of w ate r, a nd to ;{ cc. of the filtered so luti on

ad d 1 or 2 dropn of a solution of cob alt an d podium

nit ri te in acetic acid * The l iquid should not be-

come turbid, and on .standing two hours at about

f>(f (>., no yellow precipitate should form.

S O D I U M N I T R I T E

NaNO* Mol. Wt. 09.09.

I

SODIUM NITRITE



212 CUHMH'M* /t'A\U/A.\7\v

s h o w n o c h a n g e o n the* a d d i t i o n o f n IVw d r o p s o f a m

s u l p h i d e s o l u t i o n .

Q u a n t i t a t i v e D e t e r m i n a t i o n . H i s so l v e 1 <rm. n

n i t r i t e i n w a t e r a n d d i l u t e t o 10 0 n \ M a k e a l u

5 0 c c . of d e c i n o r m a l p o t a s s i u m p e r m u u n m u t e t n

m ea su re d ) w i th :<()() c c . o f wa te r an d 2."> n \ of d d u ie

ac id , w ar m to •!( ) or 50 ° (• ., an d , wh ile rnu .s tui i t lya l l o w l\u\ nit-rit (» so lu tio n to ru n slo wly iufn it u nt i

colo r di sa pp ea rs , ( 'a r e must be tak en tnwardM t h

add tho ni t r i te solut ion very s lowly, I»ecau.- . r t 1M

f rom rcu l to co lor le s s a lways r equi re s .M»mr l i m r . \

t l i an 17 . ( ) c c . o f the sodium ni t r i t e so lu t ion ^ luu i td I»r

1 c c , o f d e c i n o r m a l K M u O . , 0 . 00 ; ( i, V I^ p u . n f

log . ,r

)«cS;j8.



CHEMICAL itEAUENTS 213

TKST OK PUIUTY

Su lph ate . Th e .solution of 1 Km. of nodiuiti nitropnwsidein :»() e<\ n| wafer ac idulated with I ce. of hydrochloric acidshou ld not be rendered turbid on adding barium chloride

l i

SODIUM OXALATE

(SOUKNKK N'H ()XA J,ATK)

NUJTA. Mc»l. Wt. KM,I.

A white, crystalline powder, noluble in Jil parts of cold,

aw l in Hi pa rts of boiling, wa ter. Sodium oxa late which is

to be UMMI in uridituetrie and oxidimetric (U^/tu'mitiations as

a M tandan l, is obtaiiunt by p recipitation with alcohol a nd




Chlorides and Sulphates. — Decom pose 10 gm. of sodi

oxalate by heating in a plat inum crucible, best over

alcohol lam p ( i l luminating gas contain s sulphu r) . Th e c

bonate formed is dissolved in nitric acid, and the solut

filtered off from th e carb on. On add ing silver ni tra te so

tion to half of the filtrate, no reaction for hydrochloric a

should be obtained; and in the other half no reaction sulphuric acid should be obtained on adding barium nitr

solution.

Iron and P otassium . — Decompose 10 gm. of sodium o

late by ignit ing moderately in a plat inum crucible, remov

the last t races of carbon by cautious ignit ion with a bl

l amp. The residue , when t rea ted wi th warm water in

plat inum dish, should be completely soluble, and sho



CHEMICAL HHAGENTK 215

ronted in the manner described, should impart to the sul-

huric uri«l not more than an exceedingly faint brownish

i

Qu ant i ta t ive Determ inat ion. 0 .4 to 0 .5 gm. of the sodium

n\ ulutt* dried to con stan t weight at 100° C. in cau tious ly

he ate d in a covered pla tinum crucible. In order to avo id

the error due to the sulphur in i l luminating gan7 the crucible

in helil in a s\uv\ of unbent OH provided with a round hole, or

a l ier w liu n alcohol lam p in used. The conversion of th e

O\H1U(<* in to enrbonate \H completed in from fifteen to thirty

minutes; any eurbun present is then burned off by more

Ntronjrjy h ea lin g the crucible while half covered. W hen cold,

diNsnlvr th e c on ten ts of the* crucible in water, and t i tr at e i n



216 CHEMICAL lil'lMib:\TS

TKS TS OK r r u r n

Su lph ate s. ••- Add f> gm . <>f sod ium per oxid e in s m al l *|unn-

tifies a t a tim e to a mixture* of 25 n*. of hy dm ch ln rjr arid

an d 100 ce. of wa fer. T he Hoar solution .shuulil d e v rl o p n«»

pr ec ipi tat e with barium chloride* solution on ritnud iuf twelv ehours .

H alo ge ns. Add .{ gin. of sodiu m peroxide in nia ll quu n

titles at a time to a mixture of 20 tr. of nitric acid niu\ HM) ee .

of w at er . T he clear liquid sho uld exhibit at uu* t u h|*ht

opal( vscent turbidity on the addition of .silver nitmh* Mtlufiuit.

Ph os ph at es . Add 2.5 ^tn. of scitliuiu pen»\id«* in .m:d l

({ uantities at a time to a mix ture ol 20 n \ c»f ni ti ie iwul



C l l KMKWL KKAUMN TS 217

nation of sodium peroxide is most simply o(Toc:tcui by deeom-

|ic»Nin»; il in u Lu nge gas vo lum eter,* using coba lt n itr at e as

u cata lyzer and measuring the volume of oxygon evolved.

Iiitrtniii«'f* ()./> #tu . of sod ium per ox ide in a we ighin g flask

in to fin* ou ter com partm ent, of (he decomposition flask, and in

tin* inner place a mixture of If) e<\ of dilute sulphuric, acid and

2 or II ilmpN of n .saturated solution of cob alt ni tra te. On tilt-

ing th e Ihisk, the liquid is allowed to m ix with the sod ium

peroxide, whereby the decomposition of the latter is effected.

I ee . of o at 0 ° C. and 7i\i) m m . 0.0()(>!H>4 gm . of N a 2O 2;

IM«<:. s-r,;sr»,

SODIUM PHOSPHATE

( |) |S«»l»! r\ l IlMM(««iK\ PnoHPHAT!-;; SKCONDAUV SODUTM




10 cc. of concen trated sulp huric acid. The blue color of

l iquid should not disappear within ten minutes .

Heavy Metals. — The solution of 2 gm. of sodium phosph

in 20 cc. of wa ter , ac idulated wi th 1 cc. of hydroch loric a

should a ppear unchanged on the addi t ion of hydrogen sulph

wa ter . On now adding to the l iquid 5 cc . of amm onia w a

and a few drops of ammonium sulphide solution, no prec

ta te should form, nor should a green color develop .

Arsenic. — Int o the generat ing flask of a Marsh a pp ara

int rod uc e 10 gm. of arsenic-free, me tallic zinc, and st ar t

hyd roge n with sulphur ic acid ( 1: 5) . Dissolve 2 gm.

sodium phosphate in 50 cc. of water , introduce the solut

in small por t ions a t a t ime into the Marsh apparatus ,

m ain ta in a slow strea m of the gas for abou t one ho ur.

deposit of arsenic should be visible in the reduction t



CtlK MICAL RblAiUMTS 219

SODIUM SULPHATE

N11.SO1 ! 1OII,(). Mol.VVt.a22.32.

Colorless, efl lorescent crystals , soluble in 3 parts of cold,

an d hi 0.1 pa rt of boiling, wa ter, but. insoluble in alcohol.

The aqueous .solution is neutral to l i tmus paper.

TKHTS CW IMfHITY

Suba tancas Insoluble in W ater . - 5 gm. of sodium sulp hate

should afTonl a clear solution with 50 cc. of water.

Chlorides*, He avy Metals , Calcium , and Mag nesium. — 2 0 cc.

portions of the 1:20 aqueous solution should not be affected

by hydrogen sulphide water , ammonium oxalate , s i lver ni -

t r a t e , an d s odiu m phosphate* solutions.




solut ion, no vapors of ammonia should be evolved ( to be

ascer ta ined by mois tened l i tmus paper ) .

Quan ti ta t ive De termina t ion; Sulphi tes , and Thiosulphates . —

(a) Dissolve 1 grn. of sodium sulph ide in water an d dilu te

to 100 cc. Allow 20 cc. of thi s solution to run in to

a mixture of 20 cc. of decinormal iodine and 3 cc. of

hydrochloric acid which has been diluted with 100 cc.

of wa ter . Ti tra te the excess of iodine with decin or-

mal sodium thiosulphate , us ing s tarch solut ion as

the indicator .

1 cc. of decin orm al I = 0.012015 gm . of Na 2S + 9H 2O

log. 07972.

(6) T o 100 cc. of a solu tion of 1 gm . of sodium su lph ide in

suff icient w ater to m ak e 100 c c , add 2 gm. of crys -



CHEMICAL UtiMUWTX 221

S O D I U M S U L P H I T E

I

SODIUM SULPHITE, CRYSTALS

\it:S<), ! Til O. Mol. Wt. 'J52.27.

Culorliw, prLsiiuitic crystals, efllorcseeut in air, and easily.soluble iu \vut«T, Tin* aq ueo us solution is alkaline to l itm us

p a p n \

TUSTS OF PURITY

H ea vy M etals and Arsenic. Th e tests arc*, carried ou t as

dHui l rd under Sodium Bisu lphi te .

Q ua ntit ativ e Dete rmin ation. Dissolve I gm. of sodium




less th a n 1 pa rt of cold wa ter. Th e 1:1 aqueou s solution

s lightly alkaline to l i tmus paper.

TESTS OF PURITY

Carbonates, Sulphates, and Sulphites. — To a solution

3 gm. of sodium thiosulphate in 50 cc. of water, add dec

normal iodine solution (about 120 cc. ) unti l the l iquid has

s l ight yellow color; on now adding barium chloride solutiono turbidi ty should ensue .

Free Alkali. — The solution of 1 gm. of sodium thiosulpha

in 10 cc. of water should not be reddened by phenolphthalein

Sulphides. — The solution of 1 gm . of sodium thio sulp ha

in 10 cc. of water should not change in appearance on th

addition of zinc sulphate solution.

Calcium. — Th e solution of 1 gm. of sodium thio sulp ha



CHNM1CAL HNAGMTS 223

shou ld uc quhv td most a slight opalescent turbidity within

ti ' i i minutes uftcr adding a few drops of silver nitrate solution.

SulphateK. Dissolve 1 gin. of sodium tu ng sta te in 25 cc.

of w n tr r, utId f> cc. of nit ric ueid, boil for ten to fifteen m in ut es ,

mid tlit-tt filter. 20 cc. of the filtrate should no t im me dia tely

|w ivi idr tvd turbid on |ho addit ion of bar ium nitra te solution.

Q uan tita tive Determ ination. Dissolve 1 gm. of sod ium

in 10 <T. of w ate r, ad d 10 cc. of hyd roch loric aci d,

(»n the vvnter-bath to dryness, and heat the residue

fur half nn h ou r at 120° ( I T re at the residue w ith 20 cc. of

hydrorhlor ic acid, and repeat the entire operation three or

four t iiui'H, Fina lly digest the residue with am m oniu m n it ra te

so lu tio n to wh irh a little nitric aeid has been add ed, filter,




THYMOL

C6H3(CH3)(OH)(C3H7)1: 3: 4 . Mol. Wt. 150.11.

Colorless, hexagonal crystals with an ethereal odor, eas

soluble in alcohol, ether, and chloroform, but difficultly solub

in wa ter ( 1:11 00) . Thym ol melts a t 50 to 51° C , and bo

at 228 to 230° C.

TESTS OF PURITY

Inorganic Matter. — 1 gm. of thy mo l on ignition shou

leave no weighable residue.

Free Acids. — Blue litm us pap er should not- be redd en

by the aqueous or alcoholic solution.

Phenol. — Th e l.\ .1100 aqueo us so lution ma y ex hib it

milky turbidi ty on the addi t ion of bromine water , but shou



< ' It EM It'A L lit] A a EN TS 225

If necessary, filter, nnd (o the filtrate* add ammonia water to

al k a li n e ivne fion, Th e ti<|tii< 1should not ac(|uiro a blue color

«\tK NIIW add ammonium sulphide solution, and allow the

m i \ h u r to sta nd for four (o five* hours at. ab ou t f>()° 0. Sho uld

any precipitate form, its weight after ignition should not

t>\vvr<l 0,002 Kin. (I'V

TIN CHLORIDE

SuC1!, ! 211,0. Mol. VVt, 225.93.

CnlnrlrNs crystals, rusily and ('oinplot^ly Holublo in alcohol,

an d in wat er acidulated with hydrochloric acid. HtannouH



220 CHEMICAL /»1/-:.W,i/-.'.W.s

adding potassium sulphoeyanate .solution, l i t tuu-t only a

slight red color should develop.

A rsen ic. — Boil 2 gin, of stau no tis ehlorid*- with 10 n \ of

hy dr oc hlo ric acid (s p. #r. 1. KM fur ,NI*VITHI miimtr-i. Tin*

liquid should remain clear and colorless lor ow* IMMIT.

Qua nti tat ive Determinat ion. h U n l w O.f* via. «*! fmumm

chloride in 2 cc. of hydrochloric nci*l i^p, ?.»r, I.HM an«i dUuti*

the solution with SO cc. of wa ter. Th ru add ."> ftu. oj pu fu.

sium and sodium tartrntr, and sodium l»icurl«iu.'it«^ unhl ti»i«

solu tion is alkalim* t<» litmus p ape r. Now li ir n ir with

d( HkinormaI iodine, using starch solution n^.the tudirutttr .

1 cc . of decinoriiml I - - 0.0 ! 12!M»ti ^m . o! S u t i , . Ifl t.u

log . 05294 .

TIN CHLORIDE SOLUTION



CHHMWAL ktiAUMNTii 227

URANIUM ACETATE, F RE E FROM SODIUM

(I'ltANYI, AeKTATN)

t <MrjI,u > b } 21M) . Moi. Wt.-124.58.

A yello w, crystallin e powder, ( w ily Holuhlo in w ater . As

tin* preparation nearly always contains some basic Halt, a

•nr .solution is obtained only on adding a little acetic acid.<

TRSTS OF PURITY

S ul ph at es Th e solution of I gm, of uranium ace tate in

20 ee . i»f w at er and 2 to .'{ ee. of dilute a cetic acid sho uld n ot

be uiterted by barium chloride solution.

So diu m . Dissolve f> gm . of uranium ace tate in 200 cc.

of w ate r, w ith ( he aid of 10 cc. of dilute acetic acid. Ad d t o




earths , 2 or 3 drops of ammonium sulphide solutino dark-brown color should develop, nor should

prec ipi ta te form.

URANIUM NITRATE

( U R A N Y L N I T R A T E )

UOo(N03)3 + 6H2O. Mol. Wt. 502.67.

Yellow crystals , having a greenish luster by reflected l ig

an d efflorescing superficially in dr y air. Ur an ium ni tr at e

easily soluble in water, alcohol, and ethe r. The a qu eo

solution is acid to l i tmus paper.

TESTS OF PURITY

Sulphates . — The 1:20 aqueous solution should not devel



acid, no rhanê .should appear on passing hydrogen

.sulphide y,ns into the solution.

WATER DISTILLED

HO. Mnl. W t. 1S.01.

Disti l led water must be neutral to l i tmus paper.

TKSTH OF PUUITY

Am mo nia and Amm onium Compounds . — 50 cc . of the

- NIHMIII .show no change on the addition of 10 to 15

d rn p s «>} Ni*sslfT§s reagent,

Chlorides, 1(H) rv , of tIi<» wa ter should show no ch an ge

on ad d in g a IVw dro ps of nitric acid followed by silver n itr at e




XYLIDINE

CGH3(CH3)2(NH2). Mol. Wt. 121.12.

A yellow to yellowish-brown liquid, having a spec

gravity of 0.981 to 0.984 ; and boiling at 212 to 215° C.

TEST OF PURITY

Substan ces Insoluble in Hydroch loric Acid. — 1 0 cc. xylidine should afford a perfectly clear solution with a m

ture of 10 cc. of hydrochloric acid and 10 cc. of water .

Z I N C

Zn. Atomic Wt. 65.4 .

A shining, white m etal , exhibi t ing a s l ight, b luish-g




As soon as the zinc has dissolved, add to the solution, drop

by drop , dec inormal po tass ium permanganate . No t more

than 0.1 cc. should be required to produce a dist inct pink

color. Should more of the pe rm ang ana te solution be required ,

the dilute sulphuric acid (15 cc. of sulphuric acid and 60 cc.

of water ) should be t i t rated for the purpose of control , without

zinc, using the same solution of decinormal potassiump e r m a n g a n a t e .

Com pounds of Sulphur , P hosp horu s, etc . — In to a narr ow

test-tube introduce 1 gm. of zinc together with 5 to 10 cc. of

dil ute , arsenic-free sulphu ric aci d, and in the uppe r pa rt of

the tube inser t a plug of cotton, which serves to hold back

th e w ate r carried off by th e escaping hydrogen. Over the



Matter Oxidi/able by Pe rm ang an ate . Hi «»l\r 10 yy\\\v. in a m ix tu re of (50 cc. of w ah j mid l.> ee, <»f p u re

centrated sulphuric acid in a Ha.k pmvided \ \11ii a M

valve . Tlic- .solution should c on tain only a \«T V hjdiJ

til-V of iiud issolv cil hlatdv flo ck s A' ;<t«»u :» ti jr / in

dissoiv( kd, add (o (he wilulion, ilrop hv «I ft .|», u<»Huai |»«»fa

pcr ina npi nu U'. Not inorr than 0,1 r<\ Jtunld In- n-

to produce a distinct pink color.This ^radc of zinc /// jimrdrv fitn/t .hoit ld, in atMui

th e ah ov c, l>c teste d as {olh»\vs;

ChlQrides. I)issolv<» «" fr;ut, oi1 \\w /hir in a luisftm

;")() cc . of ni tri c acid and U)0 c<«. ot uaf«-r. t in »

should not show more than a .slight t»pali-cm t tu rh id i

<h(k addition of s ih 'er nitratt* .^huiou,




TESTS OF PURITY

Nitrogen (f rom N itrates and Am mo nia) . — Dissolve 10 gm .

of zinc dust in a mixture of 20 cc. of sulphuric acid (sp. gr.

1.84) an d 200 cc. of w at er . A dd to the solution 100 cc.

of sodium hydroxide solution I, distil off about 50 cc. ; a n d

collect the distillate in a receiver containing about 20 cc. of

w ate r and 2 to 3 cc. of decinorm al hydrochloric acid. T itr at e

the d is t i l la te wi th decinormal po tass ium hydroxide , us ing

m eth yl o range as the ind ica tor . N ot more tha n 0.2 cc . of

the ac id should have been consumed by the ammonia .

De term ining the Value of Zinc Dus t . — Introd uce 1 gm. of

zinc dust together with a few glass beads into a flask of

about 200 cc. capacity , closed with a glass stopper , and then



234 CHEMICA L HE AUK S TS

ZINC CHLORIDE

ZnC-l*. Mcil. \V (. VM\M

A dry, white powder, deliquescent in t-he air,

soluble in w at er and in alcoho l. Th e aque oun

acid to l i tmus paper .

TMKTS OK WMUTY

Solubility (Basic Zinc Chloride). Th e solution of zinc chlorid e in 1 cc. of w ate r should he clear,

only sl ightly turbid; any turbidity caused in the s

the addit ion of X c c of alcohol should disap pe

add it ion of 1 drop of hydrochloric acid.

Sulphates. —-10 cc. of the 1 : 10 aque ous solution

with a few drops of hydrochloric acid should not b

turbid by barium chloride solution.



CHEMICAL RK AGENTS 235

<>f w at e r shou ld a cqu ire an intense blue color on ad din g

1 drop of dceinormal iodine .solution.

/ /m e iodide-starch solution di luted with 50 volum es of

w a te r sho uld not. acquire* a blue color on th e ad dit ion of

d i lu t e su lphur i c a c id .

ZINC OXIDE

Zn(). Mol. Wt. 81.4 .

A wh ite , am orp ho us powder, having a fa int yellowish

ti n g e. Zinc oxide is insoluble in water, but is soluble in

di lute acet ic acid and in mineral acids.

TKHTS OF PURITY

A rs en ic. A m ixtu re of 1 gm . of zinc oxide and 3 cc. of




Dilute the solution with 100 cc. of thoroughly boiledcooled water , and add decinormal potass ium permanga

A single drop of the permanganate should suffice to im

a dis tinct pink color to the solution.

ZINC SULPHATE

ZnSO* + 7 H2O. Mol. Wt. 287.57.Colorless crystals, slowly efflorescent in dry air, solub

0.6 p ar t of wa ter, and insoluble in alcohol. Th e aq u

solut ion is ac id to l i tmus paper .

TESTS OF PURITY

Chlorides. — Th e 1:20 aqu eou s solution shou ld no




into the generating flask of a Marsh apparatus, and start the

hy dro ge n with dilute (1:5 ) sulphuric acid. Dissolve 2 gm.

of //me su lp ha te in 20 o.c. of wate r, introd uce the solution i n

small quanti t ies at a t ime into the Marsh apparatus, and

m a in ta in a slow stream of gas for abou t half an hour. A t

the end of this period no deposit of arsenic should be visiblew it hi n the* reduc tion tu be.




INTERNATIONAL ATOMIC WEIGHTS, 1906

Aluminum. .Antimony...ArgonArsenicBarium .. . .Bismuth .. .BoronBromine .. .Cadmium.. .CaesiumCalciumCarbon . . . .Cerium ....Chlorine .. .Chromium. .CobaltColumbium .Copper ....Erbium . . . .

Fluorine ....

AlSbAAsBaBiB

BrCdCsCaCCeClCrCoCbCuEr

F

27.1120.239.975.0

137.4208.5

11

79.96112.4132.940.112.0

140.2535.4552.159.094

63.6166

19

Hydrogen ....IndiumIodineIndiumIronKryptonLanthanum .. .LeadLithiumMagnesium... .Manganese....MercuryMolybdenum..Neodymium...NeonNickelNitrogenOsmiumOxygen

Palladium ....

HInIIrFeKrLa

PbLiMgMnHgMoNdNeNiNOsO

Pd

1.008115126.97193.055.981.8

138.9

206.97.0324.3655.0

200.096.0

143.620

58.714.04191

16.00

106.5

Rubidium..RutheniumSamarium .Scandium .Selenium..SiliconSilver

Sodium*...Strontium.Sulphur...Tantalum .Tellurium.Terbium ..Thallium..Thorium ..Thulium ..TinTitanium .Tungsten .

Jranium...

RbRuSmScSeSiAg

NaSrSTaTeTbTlThTmSnTiW

U

S5.5101.7150.344.179.228.4

107.9323.0587.632.06

183127.6160204.1232.5171119.048.1184

238.5




1 CC. OF DECINORMAL POTASSIUM PERMANGANATE SOLUTION IS THEEQUIVALENT OF :

Log.

Acid Oxalic, Anhydrous H2C2O4Acid Oxalic, Cryst. H2C2O4 + 2 H2O

Ammonium Oxalate (NHO2C2O4 4- H2OHydrogen Peroxide H2O2Indigotin (Indigo Blue) C17H10N2O2Iron FeIron Sulphate, Ferrous FeSO4 + 7 H2OIron and Ammonium Sulphate FeSO

6H*9Potassium Nitrite KNO2Potassium Oxalate, Neutral K2C2O4 H- H2OPotassium Tetraoxalate KHC2O* + H0C-O4 + 2 H<0Silver N itrite AgNOa

0.00450080.0063024

0.0071080.00170080.0074150.005590.027807

0.0392260.00425950.00921580.0063550.0076985

0.0034545

6532979951

8517523065870117474144415

5935862936964538031288640




1 CC. OF DECINORMAL SODIUM THIOSULPHATE SOLEQUIVALENT OF:

A c i d I o d i c H I O 3

A c i d I o d i c A n h y d r i d e I 2O 5

B a r i u m P e r o x i d e B a O 2B r o m i n e B r .x . . . . 'C h l o r i n e C l .C h r o m i u m T r i o x i d e C rO 3

H y d r o g e n P e r o x i d e H 2O 2I o d i n e II r o n F eP o t a s s i u m B i n i o d a t e K I O 3 - H I O 3

P o t a s s i u m B r o m a t e K B r O 3

P o t a s s i u m C h r o m a t e K 2 C r 0 4

P o t a s s i u m D i c h r o m a t e K 2 C r 2 O 7P o t a s s i u m I o d a t e K I O

0 .

0 .

0 .0 .

0 .

0 .

0.

0 .

0 .

0 .

0 .

0 .

0 .

0 .



CUUMICAL REAGENTS 24 1

i tv, OF I'lvrn NORMAL HYDROCHLORIC ACID IS THE EQUIVALENT OF.-

Sodium honiU* (Vynt.* NiiglUOr h 1011/)S l | Uomt<\ AnhydrmiN ^Ntiyli^)?

Oxulato (aftor ignition) Na^'aO*

* Indica tor: Methyl Orange.

Gram.

0.0382200.02021p.()1341

Log.

582353055712743

J C<\ OF FIFTH -NORMAL POTASSIUM HYDROXIDE SOLXJTION IS THEEQUIVALENT OF:

Gram. Log.



I N D EX

Acetone, 1.Acetic Acid, 2, 3, 4 , 5.

Anhydride, 5.Acid Acetic, 2, 3, 4 , 5.

Anhydride, 5.Diluted, 30 per cent, 4 .

cent,

Acid Hydrochloric Sp. Gr. 1.19, 12.Hydrofluoric, 15.Hydrosilicofluoric, 16.Iodic, 17.

Anhydride, 18.Molybdic, 18.



244 INDEX

Acid Silicofluoric, 16.Succinic, 33.Sulphanilic, 34 .Sulphuric, 34, 36, 37.

Anhydride, 37.Concentrated, 34.Diluted, 16 per cent,

36.Fuming, 38, 39.

Fuming, Free fromNitrogen, 38.Fuming, with Phos-

phoric Anhydride,4 1.

Sp. Gr. 1.84, 34.with Phosphoric

Anhydride, 40.10 per cent, 37.

Ammonium Acetate. 53.Carbonate, 53 .Chloride, 54.Citrate Solution, 55.Dithiocarbonate SoluFluoride, 56.Molybdate, 57.Nitrate, 58 .Oxalate, 59.

Phosphate, 59.Sulphate, 61.Sulphide Solution, 62.Sulphocyanate, 61 .Sulphydrate SolutionThioacetate SolutionThiocyanate, 61.

Amyl Alcohol, 47.for Gerber'



INDEX 24 5

Benzene, 72.Benzidine, 73 .Benzin, 74.

Petroleum, 74.Benzol, 72.Bismuth Nitrate, Basic, 74.

Subnitrate, 74.Blood Charcoal, 89.

Borax, 193, 194, 195, 196.Anhydrous, 196.Glass, 196.

Boric Anhydride, 5.Boron Trioxide, 5.Bromine, 76.

Water, 77.Brucine, 77.

Caustic Soda Solutions, 207.Charcoal, Animal, 89.

Blood, 89.Chlorinated Lime, 130.Chlorine Water, 90.Chloroform, 91.Chromic Anhydride, 92.Chromium Trioxide, 92.

Cobalt N itrate, 93.Cobaltous Nitrate, 93.Collodion, 94 .Concentrated Hydrochloric Acid,

12.Sulphuric Acid, 34.

Copper and Ammonium Chloride,99.

by Electrolysis, 94.



246 INDEX

Eth yl Ether, 101, 102.

Ferric Ammonium Sulphate, 122.Chloride, 118.

Ferrous Ammonium Sulphate, 123-Chloride, 119.Sulphate, 120.Sulphide, 121.

Fuming Sulphuric Acid, 38, 39.

Furfural, 102.Furfurol, 102.

Gallein, 103.Liquid, 103.

Glycerin 103, 104.Sp. Gr. 1.250,103.Sp. Gr. 1.23, 104 .

Glycerol, 103, 104.

Iron and Ammonium Sulphatric, 122.

and Ammonium Sulphatrous, 123.

by Hydrogen, 115.Chloride, Ferric, 118.

Ferric, SolutioFerrous, 119.

Powder, 117.

Reduced, 115.Sulphate, Ferrous, 120.Sulphide, 121.Wire, 114.

Kassner's Mixture, 143.

Lacmoid, 124.Lead A cetate, 125.



INDEX 247

Magnesium Sulphate, 136.Manganese Chloride, 137.

Dioxide, 138.Peroxide, 138.Sulphate, 139.Superoxide, 138.

Manganous Chloride, 137.Sulphate, 139.

Marignac's Salt, 180.Marsh Apparatus. See PreliminaryNote.

Mercuric Chloride, 140.Oxide, 141.Potassium Iodide, 142.

Mercurous Nitrate, 14 1.Mercury, 140.

and Potassium Iodide, 142.

Palladium, 145.and Sodium Chloride, 146.Chloride, 146.Nitrate, 146.

Palladous Chloride, 146.Nitrate, 146.

Paradiaminodiphenyi, 73.Paranitrophenol, 144.

Perhydrol, 107.Petroleum Ether, 74.Phenacetolin, 146.Phenolphthalein, 147.Phenylhydrazine, 147.Phloroglucin, 148.Phosphoric Acid, 26, 28, 29.

Anhydride, 29.Phosphorous Pentoxide, 29.



24 8 /A7>/',\V

Potawium Dichromato, 104.Kerrieyaiiido, 105.Korrocyauido, I (JO.Ilydrato , 107, 10K, 170, 171.UydroNiilphido, 18,'J,Hydroxide, 107, 108, 170,

171.Purest, HIM.Purified, 171.

Purified hy Alco-hol, 170.

Solution*, 172.Iodutu, 173. *Iodide, I7:i, 175.

Nmitral, I7.r».Nitrate, 175.Nitrites 170.Oxalate, Neutral, 177.

S4*nmdary Ci

S t n l i u m

S4nKmMtf«Snit

S t h r r , 1 H 0

S t a k e d l,n

Arrtntr, !*«».

Ariit SuljilMt

Antt S t t tph i l i '

Aumlûit i , tM

and AuuuMi



INDEX 24 9

Sodium Hydroxide, with Lime, fromIceland Spar,209.

Hyposulphite, 221.Nitrate, 209.Nitrite, 2 11, 212.

Free from Potassium,212.

Nitroferricyanide, 212.Nitroprusside, 212.Oxalate, 213.Palladous Chloride, 146.Peroxide, 215.Phosphate, 217.

Secondary, 217.Pyrophosphate, 218.Sulphate, 219.

Solution Potassium Hydroxide, 172.Sulphide, 181.

Sodium Hydroxide I, 207.Hydroxide II , 207.Hydroxide III, 207.Sulphide, 220.

Stannous Chloride, 226.Zinc Iodide-Starch, 234.

Sb*rensen

3

s Oxalate, 213.Specific Gravities. See PreliminaryNote.

Stannous Chloride, 225.Sulphurated Ljjne, 87.Sulphuric Acid, 34 , 36, 37.

Anhydride, 37.Sulphur Trioxide, 37.Synthetic Indigo, 110.



250

Wator, Ammonm, 50, 51, 52. M*Prdimimiry Note.

!() pur rout, »r>2.20 | wir cent,«»28 per rout, f>0.(•(>ti(Ttitrut(

((i «

r>l.

Stronger, ^«Harytu.71.

INDKX

Xyh»liiM%, VliM).

YrllmV t%» HH

ui |*tit»^lt, Kil

Documents

Chemical Reagent Their Purity and Tests