When $10 \ mL$ of $0.1 \ M$ acetic acid $(pK_a = 5.0)$ is titrated with $10 \ mL$ of $0.1 \ M$ ammonia $(pK_b = 5.0)$,at what $pH$ will the equivalence point be reached?

The species present in solution when $CO_2$ is dissolved in water are

When a standard solution of $NaOH$ is left in the air for a few hours,

$0.1 \, M$ acetic acid is $1\%$ ionized. If its ionization increases to $10\%$,what will be its new concentration (in $, M$)?

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:

$A$ solution contains $8 \, g$ of $NaOH$ and $4.9 \, g$ of $H_2SO_4$ in $1 \, L$ of solution. What is its $pH$?