Which of the following has maximum solubility at low $pH$?

The solubility product of $AgCl$ is $1.8 \times 10^{-10}$. Precipitation of $AgCl$ will occur by mixing which of the following solutions when mixed in equal volume?

The solubility of $CdSO_{4}$ in water is $8.0 \times 10^{-4} \ mol \ L^{-1}$. Its solubility in $0.01 \ M \ H_{2}SO_{4}$ solution is $..... \ \times 10^{-6} \ mol \ L^{-1}$.
(Round off to the Nearest integer) (Assume that solubility is much less than $0.01 \ M$)

Calculate the ionic concentration of a sparingly soluble salt $BA$ in $mol \ dm^{-3}$ at $300 \ K$ when equilibrium is attained,if the solubility product of the salt is $2.7 \times 10^{-10}$ at the same temperature.

The relationship between solubility $(S)$ and solubility product $(K_{sp})$ for a salt of type $A_x B_y$ is given by:

Solubility of $B(OH)_2$ in water at $25\,^{\circ}C$ is $10^{-7} \ M$. The value nearest to $K_{sp}$ is