Titration of Weak Acids with Strong Bases
Weak monoprotic acids can be neutralized in the presence of a strong base (such as sodium hydroxide) to form a buffered solution between the excess acid and the newly formed sodium salt of the conjugate base. As base is added, but before the acid is completely neutralized, the of the solution can be calculated using the Henderson–Hasselbalch equation:, where is the negative log of the acid dissociation constant and and are concentrations in moles per liter. After the neutralization, the is determined by the amount of excess base present. The volume of base required to reach the equivalence point (point of inflection) is determined by three variables: the concentration and volume of acid present and the concentration of base being added.
K. W. Whitten, R. E. Davis, and M. L. Peck, General Chemistry, 6th ed., Fort Worth, TX: Saunders College Publishing, 2000.