Answer
The molar solubility for $CuI$ in pure water is equal to $1.13 \times 10^{-6}M$
Work Step by Step
1. Write the $K_{sp}$ expression:
$ CuI(s) \lt -- \gt 1Cu^{+}(aq) + 1I^{-}(aq)$
$1.27 \times 10^{-12} = [Cu^{+}]^ 1[I^{-}]^ 1$
2. Considering a pure solution: $[Cu^{+}] = 1S$ and $[I^{-}] = 1S$
$1.27 \times 10^{-12}= ( 1S)^ 1 \times ( 1S)^ 1$
$1.27 \times 10^{-12} = S^ 2$
$ \sqrt [ 2] {1.27 \times 10^{-12}} = S$
$1.13 \times 10^{-6} = S$
- This is the molar solubility value for this salt.