On passing $H_2S$ gas through a highly acidic solution containing $Cd^{2+}$ ions,$CdS$ is not precipitated because

If the maximum concentration of $PbCl_2$ in water at $298 \, K$ is $0.01 \, M$,what is its maximum concentration in $0.1 \, M \, NaCl$ solution?

$0.01 \ mol$ of a weak acid $HA$ $(K_{a} = 2.0 \times 10^{-6})$ is dissolved in $1.0 \ L$ of $0.1 \ M$ $HCl$ solution. The degree of dissociation of $HA$ is ............. $\times 10^{-5}$ (Round off to the Nearest Integer). [Neglect volume change on adding $HA$. Assume degree of dissociation $<< 1$]

The solubility of $AgI$ in $NaI$ is less than that in pure water because ................

At $298 \ K$ the molar solubility of $Cd(OH)_2$ in $0.1 \ M \ KOH$ solution is $x \times 10^{-y}$. The values of $x$ and $y$ are respectively (at $298 \ K, \ K_{sp}$ of $Cd(OH)_2 = 2.5 \times 10^{-14}$)

Assertion : In the third group of qualitative analysis,$NH_4Cl$ is added to $NH_4OH$ medium.
Reason : This is to convert the ions of group into their respective chlorides.