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

$A$ solution which is $10^{-3} \ M$ each in $Mn^{2+}, Fe^{2+}, Zn^{2+},$ and $Hg^{2+}$ is treated with $10^{-16} \ M$ sulphide ion. If $K_{sp}$ of $MnS, FeS, ZnS,$ and $HgS$ are $10^{-15}, 10^{-23}, 10^{-20},$ and $10^{-54}$ respectively,which one will precipitate first?

The solubility product of a salt with the general formula $MX_2$ is $4.0 \times 10^{-12}$. What is the concentration of the $M^{2+}$ ion in a saturated solution of this salt?

The $K_{sp}$ of $PbI_2$ is $1.4 \times 10^{-8}$. The molar mass of $PbI_2$ is $461 \ g \ mol^{-1}$. The molar mass of $Pb(NO_3)_2$ is $331.9 \ g \ mol^{-1}$. Find the solubility of $PbI_2$ in: $(a)$ $500 \ mL$ of water,$(b)$ $500 \ mL$ of $0.10 \ M \ KI$ solution,$(c)$ What is the weight of $PbI_2$ soluble in $500 \ mL$ of solution containing $1.33 \ g$ of $Pb(NO_3)_2$?

Two insoluble salts $MY$ and $NY_{3}$ have the same $K_{SP} = 6.2 \times 10^{-13}$ at room temperature. Which of the following statements is true regarding $MY$ and $NY_{3}$?

Precipitation of $CaF_2$ $(K_{sp} = 1.7 \times 10^{-10})$ occurs when equal volumes of which of the following are mixed?