EVALUATION OF ABILITY TO DETERMINE DISSOCIATION CONSTANTS OF AMINO ACIDS AND RELATIVELY STRONG ACIDS IN AQUEOUS SOLUTION BY POTENTIOMETRIC TITRATION METHOD

Abstract

In this study, the dissociation constants of acids such as sulfuric acid (the second dissociation constant), oxalic acid and glutamic acid were determined, through individual potentiometric titration of each studied acid solution. However, the first calculated dissociation constant of oxalic acid differs with the literature value significantly. Moreover, the first dissociation constant of glutamic acid cannot
be determined. The result shows that it needs to add strong acid to the studied acid solution for determining acid dissociation constants of amino acids and ones stronger than 10–2 of acids (pKa < 2) by the potentiometric titration method.