$A$ certain buffer solution contains equal concentrations of $X^{-}$ and $HX$. The $K_a$ for $HX$ is $10^{-8}$. The $pH$ of the buffer is

$50 \, mL$ of $0.1 \, M \, CH_3COOH$ is being titrated against $0.1 \, M \, NaOH$. When $25 \, mL$ of $NaOH$ has been added,the $pH$ of the solution will be $.... \times 10^{-2}$. (Nearest integer)
(Given : $pK_a(CH_3COOH) = 4.76$)
$\log 2 = 0.30$,$\log 3 = 0.48$,$\log 5 = 0.69$,$\log 7 = 0.84$,$\log 11 = 1.04$

$A$ certain buffer solution contains equal concentrations of $X^-$ and $HX$. If the $K_a$ of $HX$ is $10^{-8}$,then the $pH$ of the buffer solution will be ...... .

Which of the following solutions does not act as a buffer?

What is the $pH$ of the solution obtained by mixing $5.076 \ g$ of methyl ammonium nitrate $(CH_3NH_3NO_3)$ into $120 \ mL$ of $0.225 \ M$ methylamine $(CH_3NH_2$; $K_b = 4 \times 10^{-4})$?

Find the $pH$ of a buffer solution prepared by mixing $300 \, mL$ of $0.3 \, M \, NH_3$ and $500 \, mL$ of $0.5 \, M \, NH_4Cl$. Given $K_b$ for $NH_3 = 1.8 \times 10^{-5}$.