Q. What volume of $\frac{M}{10}\ NaOH$ added in 50 mL, $\frac{M}{10}$ acetic acid solution to get a buffer solution having highest buffer capacity?
A) $50$ mL
B) $25$ mL
C) $10$ mL
D) 40 mL
Explanation
(b)
Buffer capacity of a buffer solution is maximum when the concentration of the weak acid and its salt or weak base and its salt are equal, $i.e$., for highest buffer capacity $pH = pK_{a}$
For this $\lbrack salt\rbrack = \lbrack acid\rbrack$
Thus, 25 mL.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.