Question

Assertion: On mixing equal volumes of 1 M $HCl$ and of 2 M $C{H}_{3}COONa$, an acidic buffer solution is formed.
Reason: The resultant mixture contains $C{H}_{3}COOH$ and $C{H}_{3}COONa$ which are parts of acidic buffer.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Assertion is incorrect but Reason is correct
• E. Both Assertion and Reason are incorrect

Answer 1

Answer: (A)

Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

A solution that resists change in pH value upon addition of small amount of strong acid or base (less than 1 %) or when solution is diluted is called buffer solution.

Acidic buffer solution : An acidic buffer solution consists of solution of a weak acid and its salt with strong base. The best-known example is a mixture of solution of acetic acid and its salt with strong base $\left(C{H}_{3}COONa\right)$.

Reaction:

$C{H}_{3}COONa+HCl\to C{H}_{3}COONa+C{H}_{3}COOH$

2 1 - -

1 - 1 1

which are parts of acidic buffer