2. Buffering Capacity

The total amount of hydrogen ions (acid) or hydroxide ions (base) that can be added to a buffer solution without causing a significant change in pH, is determined by the concentrations of the buffering components. The greater the concentrations, the greater the buffering capacity.

The capacity of a buffering solution containing 1.0 mole of A (weak acid) and 1.0 mole of B (the conjugate weak base) B in 1.000 L solution is ten times larger than the capacity of a buffering solution only containing 0.1 mole of A and 0.1 mole of B. On the other hand, the pH of both buffers is the same.

First buffering solution (1 mol/L)	Second buffering solution (0.1 mol/L)

Summary

Buffering Capacity
= total amount of hydrogen ions (acid) or hydroxide ions (base) that can be added without causing a significant change in pH
determined by the concentrations of the buffering components