Answer
Kps=1.09 x 10⁻⁵
Procedure
First, we will need to consider the solution equilibrium. In this case, we have the following equation that depicts the equilibrium.
[tex]Ca(OH)_2\leftrightarrows Ca^{2+}+2OH^-[/tex]The molar solubility will be given by the following equation If only 0.238 g of Ca(OH)₂ is dissolved in enough water to give 0.230 L
[tex]S=\frac{\frac{0.238\text{ g Ca\lparen OH\rparen}_2}{74.09\text{ g mol}^{-1}}}{0.230\text{ L}}=0.01397\text{ M}[/tex]Therefore the Kps value will be determined as :
[tex]kps=s(2s)^2=(0.01397)(2\times0.01397)^2=1.09\times10^{-5}[/tex]