A,B and C are three buffer solutions, each of which composed of a weak acid and its salt. For increasing the pH by 0.02 units, it is found that 1.0, 1.4 and 1.2 millimol of NaOH are required for A,B and C, respectively. Arrange the solutions in the increasinng order of their buffer capacity.

Explanation

The higher the buffer capacity of a buffer solution, the greater the amount of a strong acid or a strong base to be required for increasing the pH of the buffer. It is given that increasing pH of the buffer by the sae amount requires minimum amount of NaOH for the buffer A and maximum amount of NaOH for the buffer B. therefore, the increasing order of buffer capacity of the given buffers is `A lt C lt B`.