Arrange the following in increasing order of solubility product $(K_{sp})$: $Ca(OH)_2, AgBr, PbS, HgS$

The solubility product of silver chloride at $298 \ K$ is $1.8 \times 10^{-10}$. The solubility of $AgCl$ in $0.2 \ M \ NaCl$ solution will be ............

$A$ solution is $0.1 \ M$ in $Cl^{-}$ and $0.001 \ M$ in $CrO_{4}^{2-}$. Solid $AgNO_{3}$ is gradually added to it. Assuming that the addition does not change in volume and $K_{sp}(AgCl) = 1.7 \times 10^{-10} \ M^{2}$ and $K_{sp}(Ag_{2}CrO_{4}) = 1.9 \times 10^{-12} \ M^{3}$. Select the correct statement from the following:

The solubility product of a sparingly soluble salt $A_2B$ is $3.2 \times 10^{-11}$. Its solubility in $mol \cdot L^{-1}$ is

The $K_{sp}$ value for $Gd(OH)_3$ is $2.7 \times 10^{-23}$. At what $pH$ will $Gd(OH)_3$ begin to precipitate? (Given: $\log 3 = 0.48$)

Which of the following is insoluble in water?