An aqueous solution of strong monoacidic base is of $1 \times 10^{-4} \mathrm{M}$. What is the value of pH at $25^{\circ} \mathrm{C}$ ?

Acidic buffer solution is prepared by mixing proportionate quantity of

The degree of dissociation of 0.01 M solution of $\mathrm{NH}_4 \mathrm{OH}$ is $4.2 \times 10^{-2}$. What is the percent dissociation of $\mathrm{NH}_4 \mathrm{OH}$ ?

Conjugate acid of $\mathrm{NH}_2^{-}$and $\mathrm{NH}_3$ are respectively