Ksp and Common Ion?

Question

Ksp = 7.9 x 10^-27

Cadmium(II) hydroxide is added to a one liter solution that has sodium hydroxide, and thus a pH of 12 (so obviously pOH=2).

what is the approximate molar concentration of cadmium ions in this solution?

Answer 1

Cd(OH)2<--->Cd++ + 2OH-

Ksp = [Cd++][OH-]^2
if pOH =2 [OH-]= 10-2

So [Cd++]= Ksp/10^-4=10^4Ksp= 7.9*10^-27*10^4=7.9*10^23