At $25^{\circ}C$,the solubility product $(K_{sp})$ of $Zn(OH)_2$ is $10^{-14}$. If $NH_4OH$ is $50\%$ dissociated,what will be the concentration of zinc in a $0.1 \ M$ $NH_4OH$ solution?

Assign $A, B, C, D$ from the given type of reaction.
$ZnS(s) + 2HCl(aq) \longrightarrow ZnCl_2(aq) + H_2S(g)$

The solubility products of $NiS$,$ZnS$,$CdS$,and $HgS$ are $4.7 \times 10^{-5}$,$1.6 \times 10^{-24}$,$8 \times 10^{-27}$,and $4 \times 10^{-53}$ respectively. An aqueous solution contains $Ni^{2+}$,$Zn^{2+}$,$Cd^{2+}$,and $Hg^{2+}$ of equal concentration. $H_2S$ gas was passed into this solution very slowly. The first and the last ions that precipitate as sulphides are respectively.

Which compound does not dissolve in hot dilute $HNO_3$?

The solubility product of $Mg(OH)_2$ is $1 \times 10^{-12}$. At what $pH$ will precipitation occur in a $0.01 \ M$ $MgCl_2$ solution?

Solid $Ba(NO_3)_2$ is gradually dissolved in $1.0 \times 10^{-4} \, M \, Na_2CO_3$ solution. At which concentration of $Ba^{2+}$ will the precipitation begin? $(K_{sp} \, BaCO_3 = 5.1 \times 10^{-9})$