Chemistry · Ionic Equilibrium

Consider two Group IV metal ions X2+ and Y2+. A solution containing 0.01 M X2+ and 0.01 M Y2+ is saturated with H2S. What is the pH at which the metal sulphide YS will form as a precipitate? (Nearest integer) (Given: Ksp(XS) = 1 × 10-22, Ksp(YS) = 4 × 10-16, [H2S] = 0.1 M, Ka1 × Ka2(H2S) = 1.0 × 10-21, log 2 = 0.30)