1) A saturated solution of H2 S in 0.1 \M HCl at 250 C contains S2- ion concentration of 10-23 mol L-1. The solubility product of some sulphides are CuS= 10-44, FeS =10-14 , MnS=10-15 , CdS=10-25 . If 0.01 M solution of these salts in 1 M HCl are saturated with H2S which of these will be precipitated? A) All B) All except MnS C) AU except MnS and FeS D) Only -CuS Answer: Option CExplanation:$[S^{2-}]=10^{-23} mol L^{-1}$ $[M^{2+}]=10^{-2} M$ Ionic product , $K_{1p}=[M^{2+}][S^{2-}] =10^{-25}$ $\therefore$ ionic product is greater than Ksp of CuS and CdS. Therefore , all except MnS and FeS are prescipitated
