Question

Aqueous solution of $HN{O}_3,KOH,C{H}_{3}COOH$ and $C{H}_{3}COONa$ of identical concentration are provided. The pair(s) of solution which forms buffer upon mixing is (are)

• A. $HN{O}_3\text{and}C{H}_{3}COOH$
• B. $KOH\text{and}C{H}_{3}COONa$
• C. $HN{O}_3\text{and}C{H}_{3}COONa$
• D. $C{H}_{3}COOH\text{and}C{H}_{3}COONa$

Answer 1

The correct option is D $C{H}_{3}COOH\text{and}C{H}_{3}COONa$

A buffer solution is an aqueous solution consisting of a mixture of a weak acid and its conjugate base or weak base and its conjugate acid.

Of all options, only in option "D", there is a pair of a weak acid and salt of its conjugate base.

Hence, Option "D" is the correct answer.