Thermodynamics of (+)-tartaric acid and its sodium and potassium complexes

Abstract

The dissociation constants of (+)-tartaric acid at 25 °C have been determined in 0·1, 0·2, and 0·4 (Me₄N)Cl media by potentiometric titration using a glass electrode. Thermodynamic constants have been determined at 15, 25, and 35 °C and standard enthalpy and entropy changes obtained from the temperature variation of the constants. The stability constants of sodium and potassium tartrate and hydrogen tartrate complexes at 25 °C in 0·2 (Me₄N) Cl have been obtained from pH measurements with a glass electrode.