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Studies in oxidation-reduction reactions
.\S;:\I~YTIC.\
CIfIbIIC.\
:\CT.\
317
Tn the lxcscnt invcstigution an attempt 1~1slxxm nx~cl~ to clctc*rrninc irlclircctly llyclrogcn lxx-osidc, lead diosiclc, inangancsc tliosidc, sclcnium tlioxidc, sodium formate, sodium sulphiclc, sodium mctavanadatc, potassium iodatc and copper sull)llatc by a volumetric method, using chloraminc-13 as an osidizing agent. In all titrations with chloraniinc-13, 5 ml of 0.02Jf iodine monocliloriclc, 5 ml of cllloroform and enough of hydrochloric acid to keep its normality bctwccn 4h’ to 5:V wcrc added to tllc titrant in ;L conical flask. Chloraminc-I3 was aclclccl from a burcttc until the solution, whicll was colourcd with iodine, bccarnc pale yellow. The conical flask was then stoppcrcd and vigorously shaken. Addition of small volumes of chloraminc-I3 solution WLS continued, shaking vigorously after each addition, until the chloroform layer was faintly violet. The reagent was then added dropwisc, with shaking after the nclclition of each drop, until the chloroform layer cliangcd its colour from violet to light p;~lc yellow. The end-point was very shaq>.
Hydrogen
peroxide As,O,
reacts with arscnious +
2 I-1,0,
-= As,O,
osiclc in alkaline
medium :
-I- 2 l-I,0 .,
A known weight of llydrogcn ])crosidc was taken in :I conical flask and LL known csccss of arscnious osidc dissol\*cd in ten p’cr cent. sodium hydrosidc solution was aclclcd to it. The misture WZLS :~llowcd to stand for a couple of minutes ancl acidified with concentrated hydrochloric acid. 5 ml of o.oz:ll iodine monochloriclc and 5 ml of chloroform wcrc :~cldecl to it. The conical flask was stoppcrcd and tlic misturc was vigorously sliakcn. The csccss of arscnious osidc. left unreactcd in the misturc, was dctcrmincd by titrating it against standard chloraminc-l3 solution. i\s,O, -I- 2 C,H,SO,N (Na)Cl + 2 I-I,0 =--=As& -I- 2 C,‘H,SO,h’I-I, -I- 2 N7aCl The results arc given in Table I.
_ 1v/
IO
.4h20:,
A?/
;1tltlecl
.
-VI I o As@, by H,O,
10 Chlornminc-13 uscrl
for cxccss As,On
Potassium iodide drochloric acid :
ml
rg*oo 17.00 20 00 3G.00 SO.00
‘1.00 “-7.5 1.65
reacts
ml r4.2.5 Js.35 33.20 _\G*‘}O
3.60
the
diosidcs
&T
11 .oo
2.80
with
founcl
.
.__-
III 1
l-1,0,
usal
in 1)rcscncc
.
.
o.oxs7 0.02‘12 0.0312 0.0565 0.0789
of concentrated
hy-
KI -I_ PbO, -I- -1 I-ICl ::: PbCl, -t_ KC1 -I- ICl + 2 I-I,0 KI -b MnO, -k 4 T-ICI =- MnCI, -I- KC1 -I- ICl -t_ 2 I-I,0 In prcscncc
of hydrochloric
acid,
potassium
iodide
reacts
-k 2 I-ICl = ICC1 -/- NaCl +
I<1 -}- C&SO,N(Na)Cl
with
chloraminc-B
:
ICl _1- C,I-I$O,NM,
A known weight of tlic clioxidc was taken in a conical flask and a known esccss of potassium iodide solution was ad&cl to it. The mixture was acidified with hydrochloric acid to keep its normality bctwccn L1N to gN. 5 ml of 0.02iU ioclinc monocl~loriclc and 5 ml of chloroform wcrc added to it. The cxccss of iodide was titrated back with stanclnrcl chloraminc-I3 solution. The results arc given in I’ablcs II and III.
.-
X%0.. N/20 I<1 tn1teIi :1tlclccl -_._-._. ._... __ . ml
6
O.O‘I30 0. r2go 0.13 0.182‘1
16
O.?,gY‘I
--.
8.00 I.fj.00 z’o.00 L5.00 30 00
- - ----
ml
. __
__- _._-- . -- -.._
X/I0 Chlornminc-U usccl for csccss ICI ._ .__. _...-. --
_
__ _
M/20
usccl by
KI
l’l,Oz
. . _ -.
.
.--_
l?bOa founcl
. ml
g
0.0.130 0. I”01 0. I3 IG
3.60
4.40
lO.YO TT.00
9.70
15.30
S..{O
2 r.60
0.1829 (3.2533
.
_
O_sII~..\~fIOS-I1EDUC’rIOB
11 (1)5_1)
VOL.
RI3:\CTIOss
TABLE ._.. -.
,v/20 I<1 ndclccl . . .--... ml
MnO, taken lz 0.0325 o.oqSo 0.084s O.IIGY
_.-.._-.
_-
oi
In acid medium N,‘II,
..-
.
-
..--_
.-
-.--
Chloramine-B for
-
CXCCSS
-.. _ ..-.
M/20
ICI
uscd
by
..-
I<1
MnO, found
MnO,
-
2.5’ s.9s .5*.5o 3.15
dioxide
reacts
ScO,
.
III
ml
sclenitrwt
cliosidc
_._ o
Llsccl
IO.00 20.00 zg.00 30.00 _.___ . .-- ...-. --
D ~rtcr~rlinc~iion Sclcnium
X/I
319
II
-}-
with hyclrazine
sulphute
N2H, = Se + N, +
hydrazinc
-t_ 2 C,H5S0,X
sulphatc
(Nn)Cl
2
-
to the
equation :
N,O
with
reacts
according
chlornminc-13 :
N, -t_ 2 N:iCl +
2 C&J,SO,N’I-I,
A known weight of sclcnium clioxiclc w;~s clissolvccl in minimum quantity of hot water and a known cxccss of M/r0 hydrazinc sulphatc solution was aclclccl to it. The misture was heatccl to boiling. Sclcnium that sc~pi~ratd was rcmovccl by filtration. The unused hyclraxinc sulphatc in the filtrate was titrntcd against stanclarcl chloramine-I3 in prcsencc of hyclrocldoric acid, 5 ml of o.ozA,1 iodine The results arc rccorclctl in Table IV. monochloridc and 5 ml of chloroform. *l-AT3T-T3 TV
sco, taken
M/lo
N,H,H,SO, added -
ml
N/IO Chloraminc-13 usccl for cscess N2H4H2S0,, _.. _ ml
b’ 0.0777
10.00
X2.00
O.Oc_)CJ(j
12.00
X2.00
rg.00 20.00 2g.00
0.1330 O.IGGO 0.2040 -
11l/ro N,T&H,SO, usctl by sco, ml j.“” 0.00
12.00 ‘20.00
12.00 15 00
20.Zj0
lY..IO
_- ._..
Ddcr)ni~w~tion
o/ sodium
Soclium form&c
/orrr~!rt~
rccluccs mercuric
I-ICOONa
+
chloride
2 HgC1, :-= H&Cl,
. SCO, found
to mT1crcurouscllloridc*: -I- XaCl -}- HCl -j- co,
6 0.0777 ~J.O‘XKl 0.1332 o.rGGg 0.
‘042
sIx(;lI,
13.
320
In prcsrncc of hyclrocl~loric mercuric chloride : I-Ig&l,
VOL. 11 (1954)
SOC)D
acid, chloraminc-13 oxidizes
(N&l
-I- CJ-I,SO,N
c.
I<.
-I- 2 I ICL :: 3 I l&l,
xncfcurous chloride
-{- NaCI
to
-j- C&SO,NI-I,
A known wciglit of sodium formntc was taken in a conical flask. Some soclium acctatc solution, a11 csccss of saturatccl mercuric chloriclc solution and enough was ol wxtcr to m;il;~ the volume to :~lx~~t. 75 ml wcw aclclccl to it. ‘I’llc misttlrc 11(~atccl on ;I steam Ixltli for about two lwurs until tlic whole of c:irlxm tliosidc was cvolvccl. ‘1’1~ Tlask was cooled ancl tlw Ix-ccipitatccl mercurorls cllloridc filtcwcl.
‘I’hc
l)rccil~itatc
illOl1~
with
tlic
filter
l)xlxr
w;iS triuIsfcrrd
to
a conical
flask, ancl titrxtccl against st:Ll~d:lrd chloraminc-B solution ztftcr the addition l~yclrochloric acirl, iotliiic: monocliioritlc and chloroform. ‘I‘tic results arc given ‘l’ill>lC 1’.
---
------.-
.--.
.
-
- -. .._ ..--
HCOONa ---.----.------.--
l_iLlCC!n
-----
. -__________-_ IlSCd
.-_.._ ---_-_____._
- .--. -- _.__ .-_
. .-_
.
-_ ._ ______-
4.00
o.or3o
(3.00
0.0204
-.
osidc
oxide. in prcscncc
-I- G I-ICl = L&S,
is osiclisccl to arsenic
-I- 3 C,,I-I,SO,N (Na)Cl
+
. .
__ ._
-
__ .-
10.00 0.0340 o.od+78 14.05 0.0678 19.95 - .- _____ __-- --_____ _. ___ ______ .- _.. __.
Socliunl sulpliiclc reacts with iLrScnious 3 Nu,S -I- As,O,
..
6
0.0x36
----_
_...
IICOONiL found _ ._-__- -._ -.--
0.0204
0.0340 0.0476 0.0680 ----- .----._ --.---___ - .---
k&O,
_._.
ml
b’
Arscnious
---_-
N/I o Chloraminc-I3
of in
_ _.._. -_-_
01 l~yclrocliloric
acid:
-I- 6 NnCl _1- 3 I-1,0
osidc by chloraminc-B
a I-I,0 = As,O, -t- 2 NaCl +
in acid 2
medium :
C,H,SO,NH,
I.5000 g of sodium sulphidc wcrc dissolved in 100 ml of water and a known csccss of arscnious osidc (z.505S g) dissolved in sodium hydroxide was added to it. The misturc was thoroughly stirred and acidified with dilute hydrochloric acid, when yellow prccipitatc of nrscnious sulphide was formed. The precipitate \vas filtcrcd, wasl~ccl with water and the filtrate made up to 350 ml. The cscess of arscnious oxide prcscnt in the filtrate was determined by titrating it against standard chlornminc-1’3 after the addition of hydrochloric acid, iodine monochloriclc and chloroform. The results arc tabulated in Table VI.
.
---.
-.
-
I .jOOO _
_.__ _
__....-.
- -.-.- --.-
ml
LO.00 20.00 20.00
20 00 dO.OC> :0.05
1,0.00
LO.00
____-.
Dctcrrrrintrtion Scxlium rnccliurn :
_-
ml
s
_
-_ _.
Filtrate .,V/ I o Chloramtaken for inc-13 used titration for As,O, _ -.._ ---. _ ..-- ------
Na,S taken
__..-. .._-
of sodium
.&I-I,,
-.-__
---._ __.-.- ._-.- __-.. As-O, NazS u&l found by Na2S ._
A%% in 250 ml of flltratc _____
6
I .“370
fs
I. zGHH .
.
I .5000 -.
rrr~t~tv~lrltrrl~llc:~
-}- _I NiXCIS
In Ix-cscncc
_---.
__ -~
b’
.
mctav;mwl~~tc~
N,H,,
._.__--
rcxcts
with
hydrazinc:
-{- ‘12 MC1 :-. _FVOCI, acid.
of llyclrocl~loric
(Sn)Cl
-{- z C,,I-I,SO,X
sulpllatc~ -t -1 NaCl
cl~lornminc-13
in l~yclrocl~loric
acid
-I-- S L-I,0 .-I- N,
osiclizcs
liydrnzinc
=:- 2 NnCl -t_ :! CJ-IGSO,NI-1,
sulpllntc
:
-1_ N,
_A known wcigl~t of sodium mctavanaclatc was taken in a conical flask, ;L known csccss of stnnclarcl liyclrazinc sull)hatc solution and enough of concentrated hydrochloGc acicl to lcccp the normality of acid bctwccn (7X to 7.5N) were adclccl. ‘The misturc \viLs vigorously shaken. ‘The csccss of hydrazinc sulpliatc left unback with stanclnrd cllloraminc-L% after the addition of reacted was titrntctl and chloroform. Tlic: rcc;ults ;ux rccordccl in Table VII. ioclinc n~onoc1doridc
SODIUhI
__
-___ NnVO,
lxlkcn
.._ .__ --__--M/40 N,H,$J,YO, XlClCd
_ - .._ _
---_. -ml
6
0.3050 0.3904 0.4YSo _._ ._..__.
ml
--.a-
25.00 30.00 40.00 45.00
’ --.
__ ___.
ml
s.00
IY.00
0.1221 0.2198
iSIETAVANAUA1’E
-_- __.._ --_-~ _ __-----_ .-__ __ -_-_ lV/ I o Chloraminc-J3 M/40 NJ,H,H,SO, NaVO, iiwxl for c.xcesb nsetl by NnVO, found N,H,H,SO, _- - _.._.._. .. -. .-._.-... ...-.- -- ..__ -.. - _._- - ..-..
--_
-
._ -_.
7.00 5.00 8.00 -1.98
_...._ -...__ -..-
10.00
rs.00
Z5.00
32.00
40.02 .
--
_
. .._ -_.-__-.--
6 0. I220
o.zrcJG 0.3050 0.3904 O.L+&wZ _..-_.
___._.
Pot:tssiurn iod:Lic reacts with nrscnious osidc in prcsencc of hyclrocllloric .AS,O:, -I- WO, -I- z I-ICl =-=As,O, + KC1 + H,O -t_ 1Cl In I~ydrocl~loric acid medium As,C$ -I- ‘;! CJ1,SO,N(Na)Cl
chlornminc-I.3 reacts with -I-
2
I-I,0 =-zAs,O,
arscnious
-+- 2 NaCl -I-
2
acid:
osidc:
CJ-J,SO,NIf,
A known ;unount of potassium ioclatc W:LStaken in a conical flask and a known ~‘xccss of alscnious osidc dissolved in ten per cent. sodium hydroxide solution WLS added to it. The misturc WELLS aciclificd with concentrated hydrochloric ;lcid to Icccl~ the normality between IN to $V. ‘l’hc mixture was vigorousl\ shalccn. Tl:c cxccss of arscnious oxide left unrcnctcd was titrated back with stan(lard cllloraminc-U solution after the acldition of iodine monochloridc and chloroloml. Tlic results ill32 given in ‘I’:111lcVIII.
PO rhssxuhl
IOLlATE
M/q0 R+O:, N/I0 Chloraminc-7% IlSCd by usccl for C’SCCSS Ji. LO,, AS30:, . . _. ._._ . .
X10, f0t111c1
ml
1111
R
7.35 s.35
4 .fis (i&g
o.orqg 0.0356
0.32
o.oqc)qa
I0.W
1 ‘.OO I.1 .Gg
13.00 1.5.3.5
o.oGq 2 O.Oi84
A known wcigllt of copper sulphatc wns dissolved in water and saturated with sulphur diosidc gas. The solution was boiled and a known csccss of standard potassium thiocyanatc was added to it.
2 CUSO,~ -(-
2
KCNS
-I- SO, -t_
2
I-I,0 = Cu,(CXS),
-t_ z I-I,SO,, -I- K,S04
The prc*cipitatcd copper thiocyanatc was filtered. The filtrate was boiled in an atmosphcrc of CO, till free from sulphur diosidc gas, diluted with water to :L kno\vll volume and titrntcd against standard chloraminc-I3 nftcr the addition of hydrochloric zzid, iodine monochloridc and chloroform. 2 I
I-I,0 =--z 19ISO,+G
Tllc results ;\rc given in ‘I’iLl>lc IS.
NrrCl+G C,H,SO,NIi,+z
I-ICN
OSID.\l
(OS-I~i
TABLE COPPElZ
.-. _. . _ CuSO,.~H,O taken .
From the can bc used lend diosidc,
. M,/Go KCNS aclclccl _ .-
III:.\C’I’IOSS
II
323
IS
SULPHATI:
. __..-. __ --.__ ._ AT/10 Chloramine-B used for escess KCNS
.._ &~/GO KCNS usccl by CuS0,.5H,O
. _.. CuSO,.51-1,O found ._..
results given in Tables I to IS, it is evident that chloraminc-13 ;LS x volumetric reagent to estimate indirectly, hydrogen pcroxidc, mangnncsc dioxide, sclcnium dio.xidc, sodium formntc, soclium
sulphidc, sodium mctavanndntc,
potassium iodatc and coplwr sulpllatc.
Chloraminc-I3 has been uscfl as an oxidizing agent in hydrochloric acid metlium for the indirect volumetric estimations of hydrogen pcroxicle, leiltl clioxicle, manganese diosiclc, sclcnium dioxide, sodium formntc, socllum sulphltlc, socllum mctnvanaclate, potassium iodatc anal copper sulphatc using iocline monochlor~tlc ar. ~1catalyst and prc-osicliser. Chloroform is used as an indicator. It is colourccl pink owing to the liberaiion of ioclinc clurlng the titration and becomes light pale yellow at the cnclwint because of the formation of Iodine monocliloridc.
La chloramine-I3 pcut ftrc utllisk conimc osyclnnt, cii solution clilorllyclrique, pour le closage volum6trque inclirect dcs ComposGs suivunts: perosyde cl’hyclro~~ne, biosycle de plomb, biosyclc clc mangan6sc, bioxycle clc s6l&xlum, formiatc clc sodium, sulfurc clc sodium, mCt.nvanaclatc cle sodium, ioclatc clc potassium et sulfate cle cuivre. On utilisc pour cctte cl6termination lc rnonoclilorure d’ioclc coxnnie catalyscur et pr&osyclant, et le chloroformc comme inclicnteur. Ce clcrnicr se colorc cn violet par l’loclc hblr6 pcnclant la titration ct clcvicnt jaunt p~~lc au point fillxl, lxw formation de monochlorure cl’ioclc. ZUSAMMENFASSiUNu’C; Dns Chlorrrmin-B lcnnn in salzsaurer Liisung nls Os~cl~Ltionstnittcl vcrwcnclct ~~rclen ftir die inclircicte x~olumctrischc Bestlmmung folgenclcr Vcrbinclungen. Wasscrstoffperosycl, Uleicliosycl, Magnesiumcliosyd, Selencli6xyc1, Natrlumformint, Natriumsulficl, Nntriummctnvanadatc Kaliumjoclat, 1Cupfcrsulfnt Fur dicsc Uestimmung wircl clas Joclmonochloricl als Katalysator und vorosydiercndes Mittel, uncl clas Chloroform als Inclikator verwenclct. Dieses letztc fiirbt sich viol&t clurcll clas wiihrencl clcr Titration frci gcwordene Joel uncl wrtl tlann sch~~-r~cl~gelb bcim Enclpunlctc; clies durch Rilclung von Jodn~onocl~loricl. Reccivecl
Tvkircli
rsth,
1354
CIfIbIIC.\
:\CT.\
317
Tn the lxcscnt invcstigution an attempt 1~1slxxm nx~cl~ to clctc*rrninc irlclircctly llyclrogcn lxx-osidc, lead diosiclc, inangancsc tliosidc, sclcnium tlioxidc, sodium formate, sodium sulphiclc, sodium mctavanadatc, potassium iodatc and copper sull)llatc by a volumetric method, using chloraminc-13 as an osidizing agent. In all titrations with chloraniinc-13, 5 ml of 0.02Jf iodine monocliloriclc, 5 ml of cllloroform and enough of hydrochloric acid to keep its normality bctwccn 4h’ to 5:V wcrc added to tllc titrant in ;L conical flask. Chloraminc-I3 was aclclccl from a burcttc until the solution, whicll was colourcd with iodine, bccarnc pale yellow. The conical flask was then stoppcrcd and vigorously shaken. Addition of small volumes of chloraminc-I3 solution WLS continued, shaking vigorously after each addition, until the chloroform layer was faintly violet. The reagent was then added dropwisc, with shaking after the nclclition of each drop, until the chloroform layer cliangcd its colour from violet to light p;~lc yellow. The end-point was very shaq>.
Hydrogen
peroxide As,O,
reacts with arscnious +
2 I-1,0,
-= As,O,
osiclc in alkaline
medium :
-I- 2 l-I,0 .,
A known weight of llydrogcn ])crosidc was taken in :I conical flask and LL known csccss of arscnious osidc dissol\*cd in ten p’cr cent. sodium hydrosidc solution was aclclcd to it. The misture WZLS :~llowcd to stand for a couple of minutes ancl acidified with concentrated hydrochloric acid. 5 ml of o.oz:ll iodine monochloriclc and 5 ml of chloroform wcrc :~cldecl to it. The conical flask was stoppcrcd and tlic misturc was vigorously sliakcn. The csccss of arscnious osidc. left unreactcd in the misturc, was dctcrmincd by titrating it against standard chloraminc-l3 solution. i\s,O, -I- 2 C,H,SO,N (Na)Cl + 2 I-I,0 =--=As& -I- 2 C,‘H,SO,h’I-I, -I- 2 N7aCl The results arc given in Table I.
_ 1v/
IO
.4h20:,
A?/
;1tltlecl
.
-VI I o As@, by H,O,
10 Chlornminc-13 uscrl
for cxccss As,On
Potassium iodide drochloric acid :
ml
rg*oo 17.00 20 00 3G.00 SO.00
‘1.00 “-7.5 1.65
reacts
ml r4.2.5 Js.35 33.20 _\G*‘}O
3.60
the
diosidcs
&T
11 .oo
2.80
with
founcl
.
.__-
III 1
l-1,0,
usal
in 1)rcscncc
.
.
o.oxs7 0.02‘12 0.0312 0.0565 0.0789
of concentrated
hy-
KI -I_ PbO, -I- -1 I-ICl ::: PbCl, -t_ KC1 -I- ICl + 2 I-I,0 KI -b MnO, -k 4 T-ICI =- MnCI, -I- KC1 -I- ICl -t_ 2 I-I,0 In prcscncc
of hydrochloric
acid,
potassium
iodide
reacts
-k 2 I-ICl = ICC1 -/- NaCl +
I<1 -}- C&SO,N(Na)Cl
with
chloraminc-B
:
ICl _1- C,I-I$O,NM,
A known weight of tlic clioxidc was taken in a conical flask and a known esccss of potassium iodide solution was ad&cl to it. The mixture was acidified with hydrochloric acid to keep its normality bctwccn L1N to gN. 5 ml of 0.02iU ioclinc monocl~loriclc and 5 ml of chloroform wcrc added to it. The cxccss of iodide was titrated back with stanclnrcl chloraminc-I3 solution. The results arc given in I’ablcs II and III.
.-
X%0.. N/20 I<1 tn1teIi :1tlclccl -_._-._. ._... __ . ml
6
O.O‘I30 0. r2go 0.13 0.182‘1
16
O.?,gY‘I
--.
8.00 I.fj.00 z’o.00 L5.00 30 00
- - ----
ml
. __
__- _._-- . -- -.._
X/I0 Chlornminc-U usccl for csccss ICI ._ .__. _...-. --
_
__ _
M/20
usccl by
KI
l’l,Oz
. . _ -.
.
.--_
l?bOa founcl
. ml
g
0.0.130 0. I”01 0. I3 IG
3.60
4.40
lO.YO TT.00
9.70
15.30
S..{O
2 r.60
0.1829 (3.2533
.
_
O_sII~..\~fIOS-I1EDUC’rIOB
11 (1)5_1)
VOL.
RI3:\CTIOss
TABLE ._.. -.
,v/20 I<1 ndclccl . . .--... ml
MnO, taken lz 0.0325 o.oqSo 0.084s O.IIGY
_.-.._-.
_-
oi
In acid medium N,‘II,
..-
.
-
..--_
.-
-.--
Chloramine-B for
-
CXCCSS
-.. _ ..-.
M/20
ICI
uscd
by
..-
I<1
MnO, found
MnO,
-
2.5’ s.9s .5*.5o 3.15
dioxide
reacts
ScO,
.
III
ml
sclenitrwt
cliosidc
_._ o
Llsccl
IO.00 20.00 zg.00 30.00 _.___ . .-- ...-. --
D ~rtcr~rlinc~iion Sclcnium
X/I
319
II
-}-
with hyclrazine
sulphute
N2H, = Se + N, +
hydrazinc
-t_ 2 C,H5S0,X
sulphatc
(Nn)Cl
2
-
to the
equation :
N,O
with
reacts
according
chlornminc-13 :
N, -t_ 2 N:iCl +
2 C&J,SO,N’I-I,
A known weight of sclcnium clioxiclc w;~s clissolvccl in minimum quantity of hot water and a known cxccss of M/r0 hydrazinc sulphatc solution was aclclccl to it. The misture was heatccl to boiling. Sclcnium that sc~pi~ratd was rcmovccl by filtration. The unused hyclraxinc sulphatc in the filtrate was titrntcd against stanclarcl chloramine-I3 in prcsencc of hyclrocldoric acid, 5 ml of o.ozA,1 iodine The results arc rccorclctl in Table IV. monochloridc and 5 ml of chloroform. *l-AT3T-T3 TV
sco, taken
M/lo
N,H,H,SO, added -
ml
N/IO Chloraminc-13 usccl for cscess N2H4H2S0,, _.. _ ml
b’ 0.0777
10.00
X2.00
O.Oc_)CJ(j
12.00
X2.00
rg.00 20.00 2g.00
0.1330 O.IGGO 0.2040 -
11l/ro N,T&H,SO, usctl by sco, ml j.“” 0.00
12.00 ‘20.00
12.00 15 00
20.Zj0
lY..IO
_- ._..
Ddcr)ni~w~tion
o/ sodium
Soclium form&c
/orrr~!rt~
rccluccs mercuric
I-ICOONa
+
chloride
2 HgC1, :-= H&Cl,
. SCO, found
to mT1crcurouscllloridc*: -I- XaCl -}- HCl -j- co,
6 0.0777 ~J.O‘XKl 0.1332 o.rGGg 0.
‘042
sIx(;lI,
13.
320
In prcsrncc of hyclrocl~loric mercuric chloride : I-Ig&l,
VOL. 11 (1954)
SOC)D
acid, chloraminc-13 oxidizes
(N&l
-I- CJ-I,SO,N
c.
I<.
-I- 2 I ICL :: 3 I l&l,
xncfcurous chloride
-{- NaCI
to
-j- C&SO,NI-I,
A known wciglit of sodium formntc was taken in a conical flask. Some soclium acctatc solution, a11 csccss of saturatccl mercuric chloriclc solution and enough was ol wxtcr to m;il;~ the volume to :~lx~~t. 75 ml wcw aclclccl to it. ‘I’llc misttlrc 11(~atccl on ;I steam Ixltli for about two lwurs until tlic whole of c:irlxm tliosidc was cvolvccl. ‘1’1~ Tlask was cooled ancl tlw Ix-ccipitatccl mercurorls cllloridc filtcwcl.
‘I’hc
l)rccil~itatc
illOl1~
with
tlic
filter
l)xlxr
w;iS triuIsfcrrd
to
a conical
flask, ancl titrxtccl against st:Ll~d:lrd chloraminc-B solution ztftcr the addition l~yclrochloric acirl, iotliiic: monocliioritlc and chloroform. ‘I‘tic results arc given ‘l’ill>lC 1’.
---
------.-
.--.
.
-
- -. .._ ..--
HCOONa ---.----.------.--
l_iLlCC!n
-----
. -__________-_ IlSCd
.-_.._ ---_-_____._
- .--. -- _.__ .-_
. .-_
.
-_ ._ ______-
4.00
o.or3o
(3.00
0.0204
-.
osidc
oxide. in prcscncc
-I- G I-ICl = L&S,
is osiclisccl to arsenic
-I- 3 C,,I-I,SO,N (Na)Cl
+
. .
__ ._
-
__ .-
10.00 0.0340 o.od+78 14.05 0.0678 19.95 - .- _____ __-- --_____ _. ___ ______ .- _.. __.
Socliunl sulpliiclc reacts with iLrScnious 3 Nu,S -I- As,O,
..
6
0.0x36
----_
_...
IICOONiL found _ ._-__- -._ -.--
0.0204
0.0340 0.0476 0.0680 ----- .----._ --.---___ - .---
k&O,
_._.
ml
b’
Arscnious
---_-
N/I o Chloraminc-I3
of in
_ _.._. -_-_
01 l~yclrocliloric
acid:
-I- 6 NnCl _1- 3 I-1,0
osidc by chloraminc-B
a I-I,0 = As,O, -t- 2 NaCl +
in acid 2
medium :
C,H,SO,NH,
I.5000 g of sodium sulphidc wcrc dissolved in 100 ml of water and a known csccss of arscnious osidc (z.505S g) dissolved in sodium hydroxide was added to it. The misturc was thoroughly stirred and acidified with dilute hydrochloric acid, when yellow prccipitatc of nrscnious sulphide was formed. The precipitate \vas filtcrcd, wasl~ccl with water and the filtrate made up to 350 ml. The cscess of arscnious oxide prcscnt in the filtrate was determined by titrating it against standard chlornminc-1’3 after the addition of hydrochloric acid, iodine monochloriclc and chloroform. The results arc tabulated in Table VI.
.
---.
-.
-
I .jOOO _
_.__ _
__....-.
- -.-.- --.-
ml
LO.00 20.00 20.00
20 00 dO.OC> :0.05
1,0.00
LO.00
____-.
Dctcrrrrintrtion Scxlium rnccliurn :
_-
ml
s
_
-_ _.
Filtrate .,V/ I o Chloramtaken for inc-13 used titration for As,O, _ -.._ ---. _ ..-- ------
Na,S taken
__..-. .._-
of sodium
.&I-I,,
-.-__
---._ __.-.- ._-.- __-.. As-O, NazS u&l found by Na2S ._
A%% in 250 ml of flltratc _____
6
I .“370
fs
I. zGHH .
.
I .5000 -.
rrr~t~tv~lrltrrl~llc:~
-}- _I NiXCIS
In Ix-cscncc
_---.
__ -~
b’
.
mctav;mwl~~tc~
N,H,,
._.__--
rcxcts
with
hydrazinc:
-{- ‘12 MC1 :-. _FVOCI, acid.
of llyclrocl~loric
(Sn)Cl
-{- z C,,I-I,SO,X
sulpllatc~ -t -1 NaCl
cl~lornminc-13
in l~yclrocl~loric
acid
-I-- S L-I,0 .-I- N,
osiclizcs
liydrnzinc
=:- 2 NnCl -t_ :! CJ-IGSO,NI-1,
sulpllntc
:
-1_ N,
_A known wcigl~t of sodium mctavanaclatc was taken in a conical flask, ;L known csccss of stnnclarcl liyclrazinc sull)hatc solution and enough of concentrated hydrochloGc acicl to lcccp the normality of acid bctwccn (7X to 7.5N) were adclccl. ‘The misturc \viLs vigorously shaken. ‘The csccss of hydrazinc sulpliatc left unback with stanclnrd cllloraminc-L% after the addition of reacted was titrntctl and chloroform. Tlic: rcc;ults ;ux rccordccl in Table VII. ioclinc n~onoc1doridc
SODIUhI
__
-___ NnVO,
lxlkcn
.._ .__ --__--M/40 N,H,$J,YO, XlClCd
_ - .._ _
---_. -ml
6
0.3050 0.3904 0.4YSo _._ ._..__.
ml
--.a-
25.00 30.00 40.00 45.00
’ --.
__ ___.
ml
s.00
IY.00
0.1221 0.2198
iSIETAVANAUA1’E
-_- __.._ --_-~ _ __-----_ .-__ __ -_-_ lV/ I o Chloraminc-J3 M/40 NJ,H,H,SO, NaVO, iiwxl for c.xcesb nsetl by NnVO, found N,H,H,SO, _- - _.._.._. .. -. .-._.-... ...-.- -- ..__ -.. - _._- - ..-..
--_
-
._ -_.
7.00 5.00 8.00 -1.98
_...._ -...__ -..-
10.00
rs.00
Z5.00
32.00
40.02 .
--
_
. .._ -_.-__-.--
6 0. I220
o.zrcJG 0.3050 0.3904 O.L+&wZ _..-_.
___._.
Pot:tssiurn iod:Lic reacts with nrscnious osidc in prcsencc of hyclrocllloric .AS,O:, -I- WO, -I- z I-ICl =-=As,O, + KC1 + H,O -t_ 1Cl In I~ydrocl~loric acid medium As,C$ -I- ‘;! CJ1,SO,N(Na)Cl
chlornminc-I.3 reacts with -I-
2
I-I,0 =-zAs,O,
arscnious
-+- 2 NaCl -I-
2
acid:
osidc:
CJ-J,SO,NIf,
A known ;unount of potassium ioclatc W:LStaken in a conical flask and a known ~‘xccss of alscnious osidc dissolved in ten per cent. sodium hydroxide solution WLS added to it. The misturc WELLS aciclificd with concentrated hydrochloric ;lcid to Icccl~ the normality between IN to $V. ‘l’hc mixture was vigorousl\ shalccn. Tl:c cxccss of arscnious oxide left unrcnctcd was titrated back with stan(lard cllloraminc-U solution after the acldition of iodine monochloridc and chloroloml. Tlic results ill32 given in ‘I’:111lcVIII.
PO rhssxuhl
IOLlATE
M/q0 R+O:, N/I0 Chloraminc-7% IlSCd by usccl for C’SCCSS Ji. LO,, AS30:, . . _. ._._ . .
X10, f0t111c1
ml
1111
R
7.35 s.35
4 .fis (i&g
o.orqg 0.0356
0.32
o.oqc)qa
I0.W
1 ‘.OO I.1 .Gg
13.00 1.5.3.5
o.oGq 2 O.Oi84
A known wcigllt of copper sulphatc wns dissolved in water and saturated with sulphur diosidc gas. The solution was boiled and a known csccss of standard potassium thiocyanatc was added to it.
2 CUSO,~ -(-
2
KCNS
-I- SO, -t_
2
I-I,0 = Cu,(CXS),
-t_ z I-I,SO,, -I- K,S04
The prc*cipitatcd copper thiocyanatc was filtered. The filtrate was boiled in an atmosphcrc of CO, till free from sulphur diosidc gas, diluted with water to :L kno\vll volume and titrntcd against standard chloraminc-I3 nftcr the addition of hydrochloric zzid, iodine monochloridc and chloroform. 2 I
I-I,0 =--z 19ISO,+G
Tllc results ;\rc given in ‘I’iLl>lc IS.
NrrCl+G C,H,SO,NIi,+z
I-ICN
OSID.\l
(OS-I~i
TABLE COPPElZ
.-. _. . _ CuSO,.~H,O taken .
From the can bc used lend diosidc,
. M,/Go KCNS aclclccl _ .-
III:.\C’I’IOSS
II
323
IS
SULPHATI:
. __..-. __ --.__ ._ AT/10 Chloramine-B used for escess KCNS
.._ &~/GO KCNS usccl by CuS0,.5H,O
. _.. CuSO,.51-1,O found ._..
results given in Tables I to IS, it is evident that chloraminc-13 ;LS x volumetric reagent to estimate indirectly, hydrogen pcroxidc, mangnncsc dioxide, sclcnium dio.xidc, sodium formntc, soclium
sulphidc, sodium mctavanndntc,
potassium iodatc and coplwr sulpllatc.
Chloraminc-I3 has been uscfl as an oxidizing agent in hydrochloric acid metlium for the indirect volumetric estimations of hydrogen pcroxicle, leiltl clioxicle, manganese diosiclc, sclcnium dioxide, sodium formntc, socllum sulphltlc, socllum mctnvanaclate, potassium iodatc anal copper sulphatc using iocline monochlor~tlc ar. ~1catalyst and prc-osicliser. Chloroform is used as an indicator. It is colourccl pink owing to the liberaiion of ioclinc clurlng the titration and becomes light pale yellow at the cnclwint because of the formation of Iodine monocliloridc.
La chloramine-I3 pcut ftrc utllisk conimc osyclnnt, cii solution clilorllyclrique, pour le closage volum6trque inclirect dcs ComposGs suivunts: perosyde cl’hyclro~~ne, biosycle de plomb, biosyclc clc mangan6sc, bioxycle clc s6l&xlum, formiatc clc sodium, sulfurc clc sodium, mCt.nvanaclatc cle sodium, ioclatc clc potassium et sulfate cle cuivre. On utilisc pour cctte cl6termination lc rnonoclilorure d’ioclc coxnnie catalyscur et pr&osyclant, et le chloroformc comme inclicnteur. Ce clcrnicr se colorc cn violet par l’loclc hblr6 pcnclant la titration ct clcvicnt jaunt p~~lc au point fillxl, lxw formation de monochlorure cl’ioclc. ZUSAMMENFASSiUNu’C; Dns Chlorrrmin-B lcnnn in salzsaurer Liisung nls Os~cl~Ltionstnittcl vcrwcnclct ~~rclen ftir die inclircicte x~olumctrischc Bestlmmung folgenclcr Vcrbinclungen. Wasscrstoffperosycl, Uleicliosycl, Magnesiumcliosyd, Selencli6xyc1, Natrlumformint, Natriumsulficl, Nntriummctnvanadatc Kaliumjoclat, 1Cupfcrsulfnt Fur dicsc Uestimmung wircl clas Joclmonochloricl als Katalysator und vorosydiercndes Mittel, uncl clas Chloroform als Inclikator verwenclct. Dieses letztc fiirbt sich viol&t clurcll clas wiihrencl clcr Titration frci gcwordene Joel uncl wrtl tlann sch~~-r~cl~gelb bcim Enclpunlctc; clies durch Rilclung von Jodn~onocl~loricl. Reccivecl
Tvkircli
rsth,
1354