What is the $pH$ of a solution containing $50 \ mL$ each of $0.1 \ M$ sodium acetate and $0.01 \ M$ acetic acid (in $.5$)? $(pK_{a} \ CH_3COOH = 4.50)$

Calculate the $pH$ of the solution in which $0.2 \, M \, NH_{4}Cl$ and $0.1 \, M \, NH_{3}$ are present. The $pK_{b}$ of ammonia solution is $4.75$.

Amongst the following solutions,the buffer solution is

What is the concentration of $[H^+]$ in $mol/L$ in a mixed solution of $0.20 \ M \ CH_3COONa$ and $0.10 \ M \ CH_3COOH$? (Given: $K_a$ of $CH_3COOH = 1.8 \times 10^{-5}$)

$20 \ mL$ of $0.1 \ M$ $NaOH$ is added to $50 \ mL$ of $0.1 \ M$ acetic acid solution. The $pH$ of the resulting solution is $....... \times 10^{-2}$ (Nearest integer).
Given: $pKa$ $(CH_3COOH)$ $= 4.76$,$\log 2 = 0.30$,$\log 3 = 0.48$.

At $298 \text{ K}$, a certain buffer solution contains equal concentrations of $X^-$ and $HX$. The $K_b$ for $X^-$ is $10^{-10}$. What is the $pH$ of this buffer solution?