Arrange the aqueous solutions of the following salts in the increasing order of $pH$: $CuSO_4$ $(I)$,$NaCN$ $(II)$,$KCl$ $(III)$.

$20\,mL$ of $0.1\,M\,NH_{4}OH$ is mixed with $40\,mL$ of $0.05\,M\,HCl$. The $pH$ of the mixture is nearest to. (Given: $K_{b}(NH_{4}OH) = 1 \times 10^{-5}, \log 2 = 0.30, \log 3 = 0.48, \log 5 = 0.69, \log 7 = 0.84, \log 11 = 1.04$) (in $.2$)

Do you expect different products in solution when aluminium $(III)$ chloride and potassium chloride are treated separately with $(i)$ normal water,$(ii)$ acidified water,and $(iii)$ alkaline water? Write equations wherever necessary.

$pH$ of a salt solution of weak acid $(pK_a = 4)$ and weak base $(pK_b = 5)$ at $25^{\circ}C$ is:

The hydrolysis constant of $0.1 \ M$ ammonium chloride is $2.5 \times 10^{-10}$. Its degree of hydrolysis is......

If the $pK_b$ for $CN^-$ is $4.7$ at $25\,^oC$,then the $pH$ of a $0.5\,M \,NaCN$ solution is: