Chemistry - Ionic Equilibrium Question with Solution | TestHub

${\mathrm{K}}_{\mathrm{sp}}\left(\mathrm{Pb}(\mathrm{OH}{)}_2\right)=4{\mathrm{s}}^3=4\times 10^{-12}$

Solubility in buffer ${\mathrm{K}}_{\mathrm{sp}}=4\times 10^{-12}=\left[{\mathrm{Pb}}^{+2}\right]{\left[{\mathrm{OH}}^{-}\right]}^2$

In buffer of $\mathrm{pH}=10,[\overline{\mathrm{O}}\mathrm{H}]=10^{-4}\mathrm{M}$

$\left[{\mathrm{Pb}}^{2+}\right]=$ solubility in buffer $=\frac{{\mathrm{K}}_{\mathrm{sp}}}{[\mathrm{OH}{]}^{-2}}=\frac{4\times 10^{-12}}{{\left(10^{-4}\right)}^2}=4\times 10^{-4}\mathrm{M}$

Ratio $=\frac{4\times 10^{-4}}{10^{-4}}=4$ times