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![g M.aCIJhusl!ldJla.n:a HM~ lnmm PII.D
MODIFIED UADTTESTFOR CHLO·lUDES
Prin-csiptr.: A1otlified lim~l tesl· is perfonned: jf"die li·mil te!!is for a .~ample (Colon~
l'orupoUJ1d) caiwot b1,;• do:1:1.~ b~· oonnal 1n1,;·tboo~ fo.r t'!Xlimph.:~ pulas...,.lnrn
pcnUW1;~aoate ~ dt"-ooloiuised b~· boil.inl, -.,ith e:thnnot filtered w. 11!010·e
precipitated mang.,nese dioxide and the filtnlle is subjerl~ to th~ t~t
i,t i:!t ooSiNJ 11pon the·chflmii:'i~1 teadion hetween sih~Pr n1Cr11h• anrl M1!11'hlt5 ddoridf's to
uhtain. :Sih·er l"hluride·:in pre.s~nce ordilutf'! n.ilric =icid. ]'he ~it.i.•~r t·hlorid~ prod110l"d in
th~· pn~DC"e ol clilu~~· niuic ac·id n~kc_s llu:. t,i.sl ~l"tiun lnrbid~ 1bt: cltcnt ,of
tllthtctity/opalesceliltT ri.cpl'ndini upon 'the .nmonnt of chlorirk )lfelieht ilil the
snb&mnre is oomrpanid with a standard CII.J'bidJ[)·/opnlescenre produced ~ - MidHion
of sih"l"'r nitrnt~ to ~• sl~-1nd~~rd sol~1tinm hHi ng a kncnvn mnm.mt of rhlorid, iitn•I lhti:
snn1-.· ,·oh,m..- ol diltill] 11ilril1
1u.:Mi u.~ u.,...._I it1 th~ lest riollllfflfl. [f Ibt!
turbklit)•/~hl'T from th~ sAllllJ[e bas bt..i.en less tb~u 'th~ standatd sohnioD, lhi•
sampltl' will ~ th11 limi.t tt-~t and vite '-rt!l'!ial. Dih1t~ nitric· a-c·id iJ. wwd in lbe limit
hi;~, or,~h1ri,w tu mi:1k~ St)1nlinn sddit .1nd -"hkh ~~,...~ ~ih·t111
~-:nttlTidr rl'f'ripililtf' ltli
rnnke solution l11rbitl 11t the ~nd of procestC.
Reacdons:
~-,cw• AgNO:,
er....AgNol
AgCI ' • ~aN01
[HI. HN03
_ _....., AgC!' • N03
2 KMnOt i , 3 C~H=.OH ~ 3 CH~~.C.HO ., 2KOH • 2 ldnO: • 2H2O
Pn~cetltU'e:
Pnp•~atio» of T~tit Solulio11 (D-fnO,J:: Oissolvc. 1.5 g ~n 50 ml of di~til~ed
water,, heal on a water-bat~ Ulld ai:l.d gradual~· 6.ml. of ethanol (95%). rool"' dilnt~ to
6fl rnl. !1th dis.tililed water ;md filter-
Take tn--o 50 mLXessJN" Cylinders.T;the'E otu~ as "'Test"' and the. atber- as -Sbodard".](https://image.slidesharecdn.com/modifiedlimittestsforchloridesandsulphates-190123110608/75/Modified-limit-tests-for-chlorides-and-sulphates-1-2048.jpg)
![M.ODIFJED1
LmlITTHf!,"T FOR SULPEIATES
llrinctple: l'.!c"liFwd Iimit l:est ~ ~rfurnied: ir·th~ Iimit Im~ r~,.,a Mmpl~(Col(n~red
cumpound) ~an.not :be, oont• by 11or-1na.t tnE.Jl1~ud. Fur en.mpfo. polns~inm
pe11nangaru1tc is de-colourised br lxrilillJ,; ,'uh ethanol. filtered to r·e111ovl?
preeipitr.ted manpnese dioxide !IDd the Dltrnte is subject~ 10 the test.
'J11e lin~il tfSt for .~ulphnl~ is ~d.rriNi nut tH1 th~ b~~is 1)f tht1 Mnrlion ~tWetin ~..rl11,m
chlc,ride and soluble s.u)_phates in the presen~ of acetie acid.. lben. the comparison or
tl1e nu·bidi~· prod~ by a Kl"·eo amoull.t of the sabslauce is do.oo v.,ith a stillldtu-d
t•~rbidit?-' ohtaihl"d frum a knOil ~nount nf s11lphnt~. Th'-' hnrh1n1 thlorid~ hM ~n
repLlced by ba.riwn sulpha1e rea1ent wbtd.1 is havibg bariwn mloride. swpbt=-te...ffee
alcohol, and a solution of]XJt::issium ~ulphate_ llatassium sulphate has 'been adde-d t:o
i~:n·rc·a&i: Uu... semith'il)"of toe t~t Th-.· iouk ,"01u-c...ntrations iH lht· m:.J(iun111~ bt."4..1n
90 nd,ium:Ni that the- soh1hility prodnct of bn.tinu1 1ul.11lutt.11 Reh ~ed. and. tlH~ ...ry
smnll illnoll.Jll of barium ~--uJphate present in the re.a,gent acts as ai ~g agent for
precipitalioo of h."lrillf'f1 ~1.1:lpbate. ir!!;11lphL11e he present j 1'!11 1he snbsl.anre lli!ldflf t~t
All,ihul b~lr•s lo pm·~nt 8icurwr•:4Jl'tur.tHiu~1 nnrl tihu[iil. pmdurn a mont unaftwm
opalt..i;s(~t!'.lk"l'/ lw-bidity....;t~li11.: ildd .he:i-lps to tnr~k~· solutwn ut·idk- and bariUD.1 stdph.att•
precipitate.f ~ is in.~Jable"il:icb gives mrbidity/opal~-
lleactio-nB:
Air~ .Ku:IJK2SD._ • BaCl1 ___.., SaSO,L+ -- 2KCl
~ Arnlc~ci.d -
SO.f .., BaCl~ ~ HaSQ_.,J + 2 Cl](https://image.slidesharecdn.com/modifiedlimittestsforchloridesandsulphates-190123110608/75/Modified-limit-tests-for-chlorides-and-sulphates-3-2048.jpg)
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Modified limit tests for chlorides and sulphates.
This document describes a modified limit test for chlorides and sulphates. For chlorides, the test is based on the reaction between silver nitrate and chloride ions to form a silver chloride precipitate in dilute nitric acid. The turbidity produced is compared to a standard solution. For sulphates, barium chloride reacts with sulphate ions in the presence of acetic acid to form a barium sulphate precipitate. The opalescence produced is compared to a standard solution containing a known amount of sulphate. Detailed procedures are provided for preparing reagents and performing the tests on samples and standards.
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Similar to Modified limit tests for chlorides and sulphates.
Modified limit tests for chlorides and sulphates.
- 1. g M.aCIJhusl!ldJla.n:a HM~lnmm PII.D MODIFIED UADTTESTFOR CHLO·lUDES Prin-csiptr.: A1otlified lim~l tesl· is perfonned: jf"die li·mil te!!is for a .~ample (Colon~ l'orupoUJ1d) caiwot b1,;• do:1:1.~ b~· oonnal 1n1,;·tboo~ fo.r t'!Xlimph.:~ pulas...,.lnrn pcnUW1;~aoate ~ dt"-ooloiuised b~· boil.inl, -.,ith e:thnnot filtered w. 11!010·e precipitated mang.,nese dioxide and the filtnlle is subjerl~ to th~ t~t i,t i:!t ooSiNJ 11pon the·chflmii:'i~1 teadion hetween sih~Pr n1Cr11h• anrl M1!11'hlt5 ddoridf's to uhtain. :Sih·er l"hluride·:in pre.s~nce ordilutf'! n.ilric =icid. ]'he ~it.i.•~r t·hlorid~ prod110l"d in th~· pn~DC"e ol clilu~~· niuic ac·id n~kc_s llu:. t,i.sl ~l"tiun lnrbid~ 1bt: cltcnt ,of tllthtctity/opalesceliltT ri.cpl'ndini upon 'the .nmonnt of chlorirk )lfelieht ilil the snb&mnre is oomrpanid with a standard CII.J'bidJ[)·/opnlescenre produced ~ - MidHion of sih"l"'r nitrnt~ to ~• sl~-1nd~~rd sol~1tinm hHi ng a kncnvn mnm.mt of rhlorid, iitn•I lhti: snn1-.· ,·oh,m..- ol diltill] 11ilril1 1u.:Mi u.~ u.,...._I it1 th~ lest riollllfflfl. [f Ibt! turbklit)•/~hl'T from th~ sAllllJ[e bas bt..i.en less tb~u 'th~ standatd sohnioD, lhi• sampltl' will ~ th11 limi.t tt-~t and vite '-rt!l'!ial. Dih1t~ nitric· a-c·id iJ. wwd in lbe limit hi;~, or,~h1ri,w tu mi:1k~ St)1nlinn sddit .1nd -"hkh ~~,...~ ~ih·t111 ~-:nttlTidr rl'f'ripililtf' ltli rnnke solution l11rbitl 11t the ~nd of procestC. Reacdons: ~-,cw• AgNO:, er....AgNol AgCI ' • ~aN01 [HI. HN03 _ _....., AgC!' • N03 2 KMnOt i , 3 C~H=.OH ~ 3 CH~~.C.HO ., 2KOH • 2 ldnO: • 2H2O Pn~cetltU'e: Pnp•~atio» of T~tit Solulio11 (D-fnO,J:: Oissolvc. 1.5 g ~n 50 ml of di~til~ed water,, heal on a water-bat~ Ulld ai:l.d gradual~· 6.ml. of ethanol (95%). rool"' dilnt~ to 6fl rnl. !1th dis.tililed water ;md filter- Take tn--o 50 mLXessJN" Cylinders.T;the'E otu~ as "'Test"' and the. atber- as -Sbodard".
- 2. 1"1."Bt __ IStarndard Tale 4n ml. of thP =•hove IPBI ~nlutinn fl'nkt- 10 mt atrhlnrld(II ~,r.ndartl ~ i.n.Ni1..ta'i.l.bn- cy·Hnder. :st1IHU,~n (2sn ppn, CU and 5:nil., nf 1i~atl~r Add i.a 1nl.1ofdihtte- nilrit acid Di1t1l~ to•50 tnL 'ii1th disliDed·wat~r Add 1.0 ntL ofmltne llitrn: acid ffilute lo 50 tnL with ~llW ,~·al~t Add l.O mL orO. l :,i,r~~'lo, soluLion Slir 9n1n,,edun~'ly w1lh pJLW rod 11ntl c.llo'I I.a ~Land (or 5 minut~~ r:ol~•~d [mmJil')it Ohsein1111ion: Thie opajesceare produce- in sample :solutio:o should not be greater th1u1 struidnrdsolu1ion. lf opalescenC'e produ.ce--5 in sample 50hUion is Jes:s th011 the 1~ C.b.loride standiml solution (250 ppm 01): JII>ilt1t'e 50 mL of 0.0824% w/' ~ohttjon ofsodinm dtloridt- lo I.OtJ m.L Vilh db1il~lNI.'Iltn. r,. DUute bl,ri<' Pd,d: rtilute 1ft)6 lnL of cCJn~. Niltk add in s11tticient dL~IiUIMt Willter to prndut"f! ioo mL 3. O.'.ll. M Silver nitrate: Dissolvf! 1.7 M. ofsilver nitrate to .100 mL wilh di5tilloo 4. lh~ q=uantjtQth-·e and ,emi-qunti1ath~ delt1rmh1~tion of eblorid"' 5. Trus. test~ But used.fur walc.t-imm.L~-iblc liqu.i&. (t. 1'heo~ce,in tht- sample aud 5landai·d 5ohation i;s rompared by kec-p~ lh~ Ne~ster cylindtin ,-gainsl dttrk biKkK:found and o~rvin~ -side by sidli.
- 3. M.ODIFJED1 LmlITTHf!,"T FOR SULPEIATES llrinctple:l'.!c"liFwd Iimit l:est ~ ~rfurnied: ir·th~ Iimit Im~ r~,.,a Mmpl~(Col(n~red cumpound) ~an.not :be, oont• by 11or-1na.t tnE.Jl1~ud. Fur en.mpfo. polns~inm pe11nangaru1tc is de-colourised br lxrilillJ,; ,'uh ethanol. filtered to r·e111ovl? preeipitr.ted manpnese dioxide !IDd the Dltrnte is subject~ 10 the test. 'J11e lin~il tfSt for .~ulphnl~ is ~d.rriNi nut tH1 th~ b~~is 1)f tht1 Mnrlion ~tWetin ~..rl11,m chlc,ride and soluble s.u)_phates in the presen~ of acetie acid.. lben. the comparison or tl1e nu·bidi~· prod~ by a Kl"·eo amoull.t of the sabslauce is do.oo v.,ith a stillldtu-d t•~rbidit?-' ohtaihl"d frum a knOil ~nount nf s11lphnt~. Th'-' hnrh1n1 thlorid~ hM ~n repLlced by ba.riwn sulpha1e rea1ent wbtd.1 is havibg bariwn mloride. swpbt=-te...ffee alcohol, and a solution of]XJt::issium ~ulphate_ llatassium sulphate has 'been adde-d t:o i~:n·rc·a&i: Uu... semith'il)"of toe t~t Th-.· iouk ,"01u-c...ntrations iH lht· m:.J(iun111~ bt."4..1n 90 nd,ium:Ni that the- soh1hility prodnct of bn.tinu1 1ul.11lutt.11 Reh ~ed. and. tlH~ ...ry smnll illnoll.Jll of barium ~--uJphate present in the re.a,gent acts as ai ~g agent for precipitalioo of h."lrillf'f1 ~1.1:lpbate. ir!!;11lphL11e he present j 1'!11 1he snbsl.anre lli!ldflf t~t All,ihul b~lr•s lo pm·~nt 8icurwr•:4Jl'tur.tHiu~1 nnrl tihu[iil. pmdurn a mont unaftwm opalt..i;s(~t!'.lk"l'/ lw-bidity....;t~li11.: ildd .he:i-lps to tnr~k~· solutwn ut·idk- and bariUD.1 stdph.att• precipitate.f ~ is in.~Jable"il:icb gives mrbidity/opal~- lleactio-nB: Air~ .Ku:IJK2SD._ • BaCl1 ___.., SaSO,L+ -- 2KCl ~ Arnlc~ci.d - SO.f .., BaCl~ ~ HaSQ_.,J + 2 Cl
- 4. PROCEDURE Preparation ofTest Solution(IOfnO.1) : Dissolve 1.5 gin 50 n1L of distilled water, heat on II water-bath and acid gradually 6 mL of ethanol (95%), cool, dilute to 60 mL with distilled water and filter. Take two 50 ml. Nessler Cylinders. Label one as "Test• and the other as ·standard'. Test Standard Take 10 mL of the above test solution !Mb: 15 ml ofsulphate standard in Nessler cylinder. solution and 15 n1L of distilled water in a Nessler cylinder Add 0.15 1nL of5.0 !VI acetic acid Add 0.15 mL of 5.0 Macetic acid Add 2.5 ntL of barium sulphate Add 2.5 ml of bariun1 sulphate reagent 1·eagent Add sufficient distilled water to Add sufficient distilled ,vater to produce 50 nil. produce 50 nil. Stirin1mediately withglass rod and allovto stand for Sn1inutes protected fron1 light bservation: The opalescence produce in sample solution should not be greate · than standard solution. If opalescence produces in san1ple solution is less than the standard solution, the sample will pass the lin1il lest for sulphates and vice-versa. Note: 1. Barhun Sulphate Reagent: ~1ix. 10 mL of 25% w/v solution of bari111n chloride and 15 mL of eth11nolic sulphate standard solution (10 ppn1 SO4 ) and allow standing for 1 minute. It should ahvays be prepared fresh. 2. Sulphate standard solution (600 ppm S04 ): Dilute 60 ml. of a 0.181% w/v solution of potassium sulphate in distilled water to 100 mL ,vith the san1e solvent.
- 5. 3. Ethanolic sulphatestandard solution (to l'l'lll S04): Dilute 1.0 ml of a 0.181% w/v solution of potassium sulphate in ethanol (30%) to 100 ml 1,1th the same solvent. 4. 5.0 M Acetic acid: Dilute 28.5 mL ofglacial acetic acid in sufficient distilk-d waler to produce too ml. 5. TI1is tC'st is nnt uscrl for water-innnis-cihlc liquirls. 6. ·111e opaleseence in the sample and standard solution is t'Ompared by k<-.,ping the Kessler cylinders against dark ba<:kgrnund and obser.fog sideby side.