Chemistry - Ionic Equilibrium Question with Solution | TestHub

When ionic product i.e. the product of the concentration of ions in the solution exceeds the value of solubility product, formation of precitpiate occurs. $\begin{array}{rl}& {\mathrm{CaF}}_2\rightleftharpoons {\mathrm{Ca}}^{2+}+2{\mathrm{F}}^{-}\\ & \text{Ionic product }=\left[{\mathrm{Ca}}^{2+}\right]{\left[{\mathrm{F}}^{-}\right]}^2\\ & \text{ when, }\left[{\mathrm{Ca}}^{2+}\right]=1\times 10^{-2}\mathrm{M}\\ & {\left[{\mathrm{F}}^{-}\right]}^2={\left(1\times 10^{-3}\right)}^2\mathrm{M}\\ & =1\times 10^{-6}\mathrm{M}\\ \therefore & \left[{\mathrm{Ca}}^{2+}\right]{\left[{\mathrm{F}}^{-}\right]}^2=\left(1\times 10^{-2}\right)\left(1\times 10^{-6}\right)=1\times 10^{-8}\\ & \text{ In this case, }\\ & \text{ Ionic product }\left(1\times 10^{-8}\right)>\\ & \text{ solubility product }\left(1.7\times 10^{-10}\right)\end{array}$ $\therefore$ Hence (a) is correct option.