The solubility product of sparingly soluble salt BA is $4 \times 10^{-13}$. Calculate the $[\text{A}^-]$ if $[\text{B}^+]$ is $1 \times 10^{-6}\ \text{M}$.

Which of the following salt undergoes anionic hydrolysis ?

Identify from the following salts an example of a salt of strong acid and weak base.

What is oxidation state of chlorine in chlorous acid?