$A$ weak base $MOH$ of $0.1 \ N$ concentration shows a $pH$ value of $9$. What is the percentage degree of ionization of the base ? $.......\%$

Consider the dissociation equilibrium of the following weak acid $HA \rightleftharpoons H^{+}_{(aq)} + A^{-}_{(aq)}$. If the $pK_{a}$ of the acid is $4$, then the $pH$ of $10 \ mM$ $HA$ solution is . . . . . . . (Nearest integer)
[Given : The degree of dissociation can be neglected with respect to unity]

The $pH$ of $0.004 \, M$ hydrazine solution is $9.7$. Calculate its ionization constant $K_{b}$ and $pK_{b}$.

For a $10^{-3} \ M \ HCN$ solution,if the degree of dissociation $\alpha = 10\%$,find the $K_a$ and $pH$ of the solution.

$HClO$ is a weak acid. The concentration of ${H^+}$ ions in $0.1 \ M$ solution of $HClO$ $(K_a = 5 \times 10^{-8})$ will be equal to:

For a weak acid $HA$ with dissociation constant $10^{-9}$,the $pOH$ of its $0.1 \ M$ solution is: