$A$ saturated solution of $BaSO_4$ at $25^\circ C$ is $4 \times 10^{-5} \ M$. The solubility of $BaSO_4$ in $0.1 \ M \ Na_2SO_4$ at this temperature will be:

In which of the following will the dissociation of $NH_4OH$ be minimum?

When $H_2S$ gas is passed into a certain solution,it reacts to form a white precipitate. The solution referred to contains ions of

Why is pure $NaCl$ precipitated when $HCl$ gas is passed through a saturated solution of $NaCl$?

Which reagent can be used to separate $Fe(OH)_3$ from $Al(OH)_3$?

$0.01 \ mol$ 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 $<< 1$]