Question

$5$ moles of an acid is required to change the $pH$ of $1$ litre of buffer by $2$ units. The buffer capacity of the solution is:

• A. $5$
• B. $3.5$
• C. $2.5$
• D. $15$

Answer 1

Answer: (C)

$2.5$

The expression for the buffer capacity is,

Buffer capacity $=\frac{Numberofmolesofacidorbaseaddedperlitre}{ChangeinpH}$

Substitute values in the above expression, we get:

Buffer capacity $=\frac{5}{2}=2.5$.