$pH$ of $0.1 \ M$ $NH_3$ aqueous solution is $(K_b = 1.8 \times 10^{-5})$

The $pH$ of $0.01 \ M$ solution of acetic acid is $5.0$. What are the values of $[H^{+}]$ and $K_a$ respectively?

The $pH$ of $0.005 \, M$ codeine $(C_{18}H_{21}NO_{3})$ solution is $9.95$. Calculate its ionization constant and $pK_{b}$.

The $pH$ of a $0.01 \ M$ weak acid $HX$ $(K_{a}=4 \times 10^{-10})$ is found to be $5$. Now the acid solution is diluted with excess of water so that the $pH$ of the solution changes to $6$. The new concentration of the diluted weak acid is given as $x \times 10^{-4} \ M$. The value of $x$ is $...........$ (nearest integer)

The $pH$ of $0.1 \, M$ solution of cyanic acid $(HCNO)$ is $2.34$. Calculate the ionization constant of the acid and its degree of ionization in the solution.

$A$ weak acid,$HA,$ has a $K_a$ of $1.00 \times 10^{-5}.$ If $0.100 \ mol$ of this acid is dissolved in one litre of water,the percentage of acid dissociated at equilibrium is closest to $...\%$