Potentiometric Titration of Weak Acids

Abstract

A desk-calculator program has been developed for determination of the equivalence point when a weak acid is titrated with a strong base. The stability constant (K^H _HA) of the acid can be computed simultaneously. When data from a potentiometric titration of boric acid with sodium hydroxide have been processed with the program the equivalence point has been determined with an accuracy of 0.3–0.4 per cent. The computed value of the stability constant of boric acid (log K^H _HA = 9.11) is in good agreement with the values given in literature.

Key Words:

• titration
• weak acids potentiometry
• stability constant