$A$ buffer solution with $pH = 9$ is to be prepared by mixing $NH_4Cl$ and $NH_4OH$. Calculate the number of moles of $NH_4Cl$ that should be added to one litre of $1.0 \ M \ NH_4OH$. $[K_b = 1.8 \times 10^{-5}]$

$A$ solution which is resistant to change of $pH$ upon the addition of an acid or a base is known as

What is the total number of buffers formed during the titration of $H_3PO_4$ with $NaOH$?

In an acidic buffer,$0.25 \ M$ $CH_3COOH$ is added to $0.125 \ M$ $NaCH_3COO$ solution. Calculate the $pH$ of the buffer. Given $K_a$ of $CH_3COOH = 1.8 \times 10^{-5}$. [Formula: $pH = pK_a + \log \frac{[Salt]}{[Acid]}$]

Find $pH$ of the resultant solution formed by the addition of $500 \ mL$ $0.1 \ M$ $Ba(OH)_2$ and $500 \ mL$ $0.6 \ M$ $NH_4Cl$ in $1 \ L$ pure $H_2O$ at $25 \ ^oC$ (Use $\log \ 2 = 0.3$,$\log \ 3 = 0.5$,$\log \ 5 = 0.7$,$K_b(NH_3) = 10^{-5}$)

The ratio of volumes of $CH_3COOH$ $0.1 \ N$ to $CH_3COONa$ $0.1 \ N$ required to prepare a buffer solution of $pH$ $5.74$ is (Given, $pK_a$ of $CH_3COOH$ is $4.74$)