The solubility of Ce(IO3) in a 0.20 M solution of KIO3 is 4.4 x10-8 M. Calculate the Ksp for Ce(IO3)3.

Answer 1

Ce(IO₃)₃ --------------------- Ce³⁺ + 3IO₃^-

1 0 0.2 ( These are ions are from KIO₃)

-S +S +3S

1-S S (O.2+3S)

Ksp = (Ce ³⁺) (IO₃^-)³

Ksp = S * (0.2)³

Rememeber since S is negligible 0.2 + S = 0.2 for the iodate ion

S= Molar solubility= Ksp/(0.2)³ = 4.4 * 10 ^-8/ (0.2)³

5.5 * 10 ^-6