Which of the following pairs of ions when mixed in dilute solutions may give a precipitate?

Solubility of an $MX_2$ type electrolyte is $0.5 \times 10^{-4} \ mol/L$,then $K_{sp}$ of electrolyte is

The solubility product of $PbCl_2$ at $298 \ K$ is $1 \times 10^{-6}$. Its solubility in $mol/L$ is:

The minimum volume of water required to dissolve $0.1 \ g$ of lead $(II)$ chloride to get a saturated solution ($K_{sp}$ of $PbCl_2 = 3.2 \times 10^{-8}$; atomic mass of $Pb = 207 \ u$,$Cl = 35.5 \ u$) is......$L$

Assign $A$,$B$,$C$,$D$ from the given type of reaction.
$HgS \downarrow + HNO_3 \text{ (Conc.)} \longrightarrow \text{No dissolution}$

The molar solubility of $CaF_2$ $(K_{sp} = 5.3 \times 10^{-11})$ in $0.1 \ M$ solution of $NaF$ will be: