The $pK_a$ of a weak acid $(HA)$ is $4.5$. The $pOH$ of an aqueous buffered solution of $HA$ in which $50\%$ of the acid is neutralized in its titration with a strong base $(BOH)$ is

$A$ certain buffer solution contains equal concentration of $X^{-}$ and $HX$. The $K_b$ for $X^{-}$ is $10^{-10}$. The $pH$ of the buffer is

What are buffer solutions? Explain types of buffer solutions with examples.

$pH$ of a mixture of $1 \ M$ benzoic acid $(pK_a = 4.20)$ and $1 \ M$ $C_6H_5COONa$ is $4.5$. What is the volume of benzoic acid required to prepare a $300 \ mL$ buffer solution (in $mL$)? $[\log 2 = 0.3]$

$0.1 \, M$ acetic acid solution is titrated against $0.1 \, M \, NaOH$ solution. What would be the difference in $pH$ between $1/4$ and $3/4$ stages of neutralization of acid?

What is the ratio of concentration of salt to concentration of weak acid in a buffer solution to maintain its $pH$ value at $7.2$ $(pK_{a} = 6.2)$?