The solubility of salt $\mathrm{BA}_2$ is $4 \times 10^{-4} \mathrm{~mol} \mathrm{dm}^{-3}$.

What is solubility product of the salt?

Solubility of $\mathrm{Ca}_3\left(\mathrm{PO}_4\right)_2$ is ' S ' $\mathrm{mol} \mathrm{dm}{ }^{-3}$. Find solubility product.

The solubility of AgBr is $7.1 \times 10^{-7} \mathrm{~mol} \mathrm{dm}^{-3}$. Calculate its solubility product at the same temperature.

What is the pH of buffer solution formed by mixing 0.01 M acetic acid and 0.05 M sodium acetate? $\left(\mathrm{pK}_{\mathrm{a}}=4.7447\right)$