A New Approach to Data Treatment in Acid-Base Potentiometric Titration II. Determination of Polyprotic Acids and Bases

This study on potentiometric titration of polyprotic acids and bases using a glass electrode is a continuation of our paper (Maslarska V., Tencheva J., Budevsky O., Anal. Bioanal. Chem., 375, 217 (2003)) [1]. The derived earlier theoretical equation was found to fit well the experimental data. A commercial software was applied and main attention was paid to the analytical result rather than to the parameters like pK-values or glass electrode constants. Specific details concerning determination of some polyprotic compounds have been discussed. The investigated species were divided into two groups depending on their acidbase strength. In both cases, calibration of the glass electrode was not necessary, since mV-mL data were used in an auto-pH-calibration procedure. Several polyprotic compounds were analysed in water and non-aqueous media to prove the analytical applicability of the developed method.