Question

The precipitate of Ag₂CrO₄ (Ksp = 1.9 x 10^-12) is obtained when equal volumes of the following are mixed

(A) 10^-4 MAg⁺ + 10^-4 MCrO₄^2- 

(B) 10^-2 MAg⁺ + 10^-5 MCrO₄^2- 

(C) 10^-5 MAg⁺ + 10^-3 MCrO₄^2- 

(D) 10^-4 MAg⁺ + 10^-5 MCrO₄^2- 

Answer 1

Correct option (B) 10^-2 MAg⁺ + 10^-5 MCrO₄^2- 

Explanation : 

Precipitation occurs when the ionic product exceeds the K_sp value. When equal volumes of two solutions are mixed the concentration of each is reduced to half. Therefore,

In first case,