The molar solubility of PbI2in 0.2M Pb(NO2)2 solution in terms of solubility product, Ksp

Molar solubility PbI2 will get suppressed in presence of Pb(NO2)2 due to commonion effect, and the following equilibria gets established.PbI2(s)⇌PbI2(aq)→Pb+2(aq)+2I-(aq)PbNO22→Pb+2(aq)+2NO20.2+S'-(aq)Ksp = (S' + 0.2) x (2S')2⇒ Ksp = 0.2 x 4(S')2⇒Ksp0.8=S'2⇒S'=Ksp0.812