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Qualitative. Analysis. salt solution. dil. HCl. confirms the. solution + ppt. presence of. Grp. 1 cations. 2+. +. 2+. Pb , Ag , Hg. H S. 2. 2. confirms the. solution + ppt. presence of. black. Grp. 2 cations. 2+. 3+. 2+. Pb , Bi , Cu. Grp. 1. ppt. 2+.
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Qualitative Analysis
salt solution dil. HCl confirms the solution + ppt. presence of Grp. 1 cations 2+ + 2+ Pb , Ag , Hg H S 2 2 confirms the solution + ppt. presence of black Grp. 2 cations 2+ 3+ 2+ Pb , Bi , Cu
Grp. 1 ppt. 2+ dissolves in hot water Pb present + dissolves in aq. NH Ag present 3 2+ blackened by NH Hg present 2 3
Confirmatory test 2+ Pb soln. yellow ppt. yellow ppt. K CrO KI 2 4 + Ag soln. white ppt. yellow ppt. HNO KI 3 2+ Hg black ppt. + Aqua regia 2 Grey SnCl white ppt. + SnCl 2 2
Confirmatory test 3+ Bi ppt. + HNO 3 black ppt. white ppt. HCl+ Na SnO NH OH 4 2 2 2+ Cu ppt. + HNO 3 white ppt. yellow ppt. HNO KI 3 2+ Pb ppt. + HNO 3 yellow ppt. yellow ppt. K CrO KI 2 4
solution NH Cl + dil.HNO + NH OH 4 3 4 Grp. 3 present reddish-brown dirty green white solution + ppt. 3+ Fe 3+ Cr 3+ Al H S 2 Grp. 4 present solution + ppt. 2+ white Zn 3+ buff coloured Al
Confirmatory test 3+ Fe HCl + ppt. (insoluble in NaOH) CH COOH blood red ppt. 3 blue ppt. KCNS K [Fe(CN) ] 4 6 Pot.ferrocynate 3+ Cr HNO + ppt. (insoluble in NaOH) 3 yellow ppt. yellow ppt. Lead acetate NaOH + Br water 3+ HNO + ppt. (soluble in NaOH) Al 3 NH Cl + H O 2 white ppt. 4
Confirmatory test 2+ Zn ppt. soluble in HCl white ppt. white ppt. CH COOH + K [Fe(CN) ] NaOH + H S 3 4 6 2 2+ Mn ppt. soluble in HCl black or brown purple colour PbO + HNO NaOH 2 3
solution (NH ) CO 4 2 3 Grp. 5 present solution + ppt. 2+ 2+ Ca , Ba Flame colour 2+ red - Ca green - Ba (NH ) HCO 2+ 4 2 3 2+ solution + ppt. Mg present
Anions Dil. H SO Test 2 4 smell of rotten egg 2- turns lead acetate paper black S 2- pungent smell S0 turns acidified K CrO soln. green 2 4 3
Conc. H SO Test 2 4 pungent smell , white fumes with NH OH chromyl chloride Cl red vapours K Cr O + conc. H SO NaOH 2 2 7 4 2 4 yellow ppt. HNO + AgNO 3 3 Br reddish brown fumes yellow ppt.
violet pungent vapours turning starch paper blue I present 2 HNO + AgNO 3 3 yellow ppt. insoluble in NH 3 brown pungent fumes intensified by adding Cu pieces 2- NO present 3 Ring test
A salt mixture containing compounds [A, yellow solid] and [B, colourless solid] gives a lilac colour in the flame test. Its aqueous solution : • (a) is alkaline. On passing H2S, it gives a black precipitate [C] which is soluble only in aqua regia. Evaporation of the aqua regia solution followed by extraction with dilute HCl and treatment with SnCl2 yields a greyish-black precipitate. • (b) On adding NH4OH, gives and orange brown precipitate [D]. The Na2CO3 extract of the salt mixture gives the following tests : • (i) On acidification with dilute HNO3 followed by addition of AgNO3 gives a yellow precipitate which is insoluble in NH3. • (ii) On acidification with dilute HCl followed by shaking with FeCl3 and CCl4 gives a violet colouration in CCl4 layer. • Identify compounds [A] and [B] of the mixture and the precipitates [C] and [D]. • Solution: • [A] = HgO; [B] = KI; [C] = HgS; [D] = NH2Hg2I3