when the solubility is the amount of solute that dissolved in a unit volume of the solvent.
and when the balanced reaction equation is:
so, by using the ICE table:
Cd(OH)2(s) ↔ Cd2+ + 2OH-
initial 0 0
change +X +2X
Equ X 2X
so the Ksp expression = [Cd2+] [OH-]^2
and we have Ksp = 7.2 x 10^-15
and when we assume the solubility = X
by substitution:
7.2 x 10^-15 = (X) (2X)^2
7.2 x 10^-15 = X*4X^2
7.2 x 10^-15 = 4X^3
∴X = ∛(7.2x10^-15)/4
= 1.22 x 10^-5 M
∴ the solubility = X = 1.22 x 10^-5 M
