Definition
Buffer Capacity (β): A quantitative measure of a buffer's ability to resist pH changes.
Mathematical Expression:
Where:
Delta B = amount (in moles per liter) of strong acid or base added.
Delta pH = change in pH resulting from the addition.
Factors Affecting Buffer Capacity
Concentration of Buffer Components: Higher concentrations provide greater capacity.
Ratio of Acid to Base: Maximum capacity occurs when
Total Buffer Concentration: The sum of the concentrations of the weak acid and its conjugate base.
Importance
Stability: Ensures the pH remains within a narrow range during chemical reactions or storage.
Biological Systems: Maintains physiological pH crucial for life processes.