The most important buffer in the blood consists of

$A$ solution of $H_3BO_3$ and borax is known as:

Which of the following is a buffer solution?

$A$ buffer solution contains $100 \ mL$ of $0.01 \ M \ CH_3COOH$ and $200 \ mL$ of $0.02 \ M \ CH_3COONa$. If $700 \ mL$ of $1 \ M \ NaCl$ is added,what are the $pH$ values before and after the addition? $(pK_a = 4.74)$

$0.1 \ mol$ of $CH_3NH_2$ $(K_b = 5 \times 10^{-4})$ is mixed with $0.08 \ mol$ of $HCl$ and diluted to $1 \ L$. What will be the $[H^{+}]$ concentration in the solution?

$A$ $0.15 \text{ mol}$ of pyridinium chloride is added to $500 \text{ cm}^3$ of $0.2 \text{ M}$ pyridine solution. Assuming no change in volume upon mixing, what is the $pH$ of the resulting solution? (Given: $pK_b$ of pyridine $= 8.75$)