Question

The solubility of $Ca{F}_2$ is $0.5\times {10}^{-4}mol{L}^{-1}$. The value for Ksp for the salt is?

Answer 1

$Ca{F}_2$ ⇌ $C{a}^{2+}+2F^{-}$

s 2s

$K_{sp}=S\times (2S{)}^2$
$0.5\times {10}^{-4}$ $[2\times 0.5\times {10}^{-4}{]}^2$
$K_{sp}=0.5\times {10}^{-4}\times 1\times {10}^{-8}$ [concentration of $C{a}^{2+}\times concentrationof2F^{-}$]
$K_{sp}=5\times {10}^{-13}$