Assign $A, B, C, D$ from the given type of reaction.
$CH_3COOAg(s) + HNO_3(aq) \longrightarrow AgNO_3(aq) + CH_3COOH(aq)$

The first and second ionization constants of a weak dibasic acid $H_{2}A$ are $8.1 \times 10^{-8}$ and $1.0 \times 10^{-13}$ respectively. $0.1 \text{ mol}$ of $H_{2}A$ was dissolved in $1 \text{ L}$ of $0.1 \text{ M}$ $HCl$ solution. The concentration of $HA^{-}$ in the resultant solution is:

Which of the following statement$(s)$ is/are correct.
$A$. The $pH$ of $1 \times 10^{-8} \ M$ aqueous solution of $HCl$ is $8$
$B$. The conjugate base of $H_2PO_4^{\ominus}$ is $HPO_4^{2-}$
$C$. $K_w$ increases with increase in temperature
$D$. When a solution of a weak monoprotic acid is titrated against a strong base,then at the half-neutralization point,$pH = pK_a$.

In which of the following cases,$pH$ is greater than $7$?

Which $pH$ value is higher in the following pairs?
$(a)$ $0.1 \ M \ HCl$ and $0.1 \ M \ NaOH$
$(b)$ $0.1 \ M \ HCl$ and $0.01 \ M \ HCl$
$(c)$ $0.1 \ M \ NaOH$ and $0.01 \ M \ NaOH$

For a $0.1 \, M$ aqueous solution of a weak acid undergoing $2\%$ ionization,the concentration of $[H^{+}]$ and $[OH]^{-}$ will be respectively: (Ionic product of water $= 1 \times 10^{-14}$)