Isentropic apparent molal compressibilities and compressibilities of ionization of carboxylic acids in aqueous solution

Abstract

Isentropic coefficients of compressibility of the homologous series of normal carboxylic acids and α-hydroxycarboxylic acids and their sodium salts have been determined from ultrasonic measurements. Isentropic apparent molal compressibilities at infinite dilution have been calculated.

Compressibilities of ionization have been calculated from the isentropic apparent molal compressibilities and also from conductance measurements at high pressures. Values from the two independent methods of measurement do not agree in a satisfactory manner, but both show a lower limiting value for the higher homologues in each acid series.