Determination of pKa values of some azo dyes in acetonitrile with perchloric acid

In this study, 10-4 M acetonitrile solutions of 15 azo dyes synthesized by coupling hydroxyl containing compounds such as phenol, 1-naphthol and 2-naphthol with diazonium salts obtained by the diazotisation of aniline and aniline derivatives were determined by potentiometric titration with perchloric acid in acetonitrile at room temperature. The turning points and the half neutralization potentials of these compounds were determined using the potentiometric titration curves obtained in order to calculate their pKa values.