$A$ weak monobasic acid is $0.04 \%$ dissociated in $0.25 \text{ M}$ solution. What is the $pH$ of the solution?

The dissociation constant of a weak acid $HA$ is $1.5 \times 10^{-5}$. Find the percent dissociation of a solution containing $0.2 \text{ moles}$ of $HA$ in $2 \text{ liters}$ of solution. (in $\%$)

If the ionization constant of hypochlorous acid $(HOCl)$ is $2.5 \times 10^{-5}$,the $pH$ of $1.0 \ M$ of its solution is $(\log 5=0.7)$.

Which of the following has the highest $pH$?

The percentage dissociation of a decinormal solution of a weak acid $HA$ is: $(K_a = 4.9 \times 10^{-8})$

The ionization constant of $HF$ is $3.2 \times 10^{-4}$. Calculate the degree of dissociation of $HF$ in its $0.02 \ M$ solution. Calculate the concentration of all species present ($H_{3}O^{+}$,$F^{-}$ and $HF$) in the solution and its $pH$.