The solubility product of a compound of the form XY2 has the value 3.3e–4. What is the molar solubility of...

Question

The solubility product of a compound of the form XY2 has the value 3.3e–4. What is the molar solubility of XY2?

A) 6.9e–2 M
B) 1.1e–1 M
C) 8.3e–5 M
D) 1.7e–2 M
E) 4.4e–2 M

I got E can anyone else confirm?

Answer 1

If s is the solubility of XY2 then

.. .. .. .. .. XY2 <=> X +2Y
Dissolve .. s
Produce.. .. .. .. .. .s .. 2s

Ksp=[X][Y]^2=s*(2s)^2=> s^3= Ksp/4=>
s= (Ksp/4)^(1/3)= ((3.3*10^-4)/4)^(1/3) =4.4*10^-2 M

So yes, (e) is correct