Given: $K_{\mathrm{sp}}\left(\mathrm{AgI}\right)=8.5\times {10}^{-17}{\mathrm{M}}^2$.The solubility of $\mathrm{AgI}$ in $0.1 \mathrm{M} \mathrm{KI}$ solution is

$\left[{\mathrm{Ag}}^{+}\right]=\frac{K_{\mathrm{sp}}}{\left[{\mathrm{I}}^{-}\right]}=\frac{8.5\times {10}^{-17} {\mathrm{M}}^2}{0.1 \mathrm{M}}=8.5\times {10}^{-16} \mathrm{M}$

A substance's solubility is the greatest quantity that will dissolve in a given amount of solvent at a particular temperature. A given solute-solvent combination's solubility is a defining trait, and the solubilities of various compounds can vary significantly.