The $pH$ of a monoacidic base is $10$. Calculate its percentage dissociation in $0.01 \ M$ solution at $298 \ K$. (in $\%$)

For the ionization of a weak acid $HA$ as $HA \rightleftharpoons H^{+} + A^{-}$,the $pH$ of a $1.0 \ M$ solution is $5$. The dissociation constant $K_a$ is:

Calculate the $[H^{+}]$ ion concentration in a $1.00 \ M$ $HCN$ solution $(K_a = 4 \times 10^{-10})$.

Calculate the $pH$ of a solution containing $6.0 \ g$ of acetic acid $(CH_3COOH)$ in $250 \ mL$ of water. Given: $K_a = 1.8 \times 10^{-5}$ at $298 \ K$,and atomic masses are $C = 12, H = 1, O = 16$. (in $.57$)

Which of the following compounds has the maximum $K_{a}$ value?

$1.0 \ mol$ of $HCl$ and $1.0 \ mol$ of $CH_3COONa$ are dissolved in water to make a $1 \ L$ solution. What is the concentration of $H^+$ in the solution? ($K_a$ for $CH_3COOH = 1.6 \times 10^{-5}$)