Consider two Group IV metal ions X 2+ and Y 2+. A — JEE Mains Chemistry Past Papers Chemistry Question

💡 Solution & Explanation

XS(s) X +2(aq.) + S 2–(aq.) For precipitation of XS(s) [X +2] [S 2–]  KSP(XS) [S 2–]  1 10 0.01   = 10 –20 YS(s) Y +2(aq) + S 2–(aq) For precipitation of YS(s) [Y +2] [S 2–] KSP(YS) [S 2–]  2 4 10    = 4 × 10 –14 Now, H2S(aq) 2H +(aq) + S 2–(aq) 2 2 a a [S ] [H ] K K 1 10 H S       [S 2–] = 2 1 10 [H S] [H ]     4 × 10 –14 [H +] 2  1 4 × 10 –7 × 10 –1 [H +]  1 2 × 10 –4  pH  4.3