Chapter 15, Problem 81E

A saturated solution of ${\text{MgF}}_{\text{2}}$ has $\left[{\text{Mg}}^{2+}\right]=2.6\times {10}^{-4}\text{M}$ and $\left[{\text{F}}^{-}\right]=5.2\times {10}^{-4}\text{M}$. What is the value of $K_{\text{sp}}$ for ${\text{MgF}}_{\text{2}}$

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