Thermophysical studies of protonated and deprotonated glycine in aqueous sodium acetate buffer solutions at different temperatures

Abstract

Interactions of glycine in water and in (0.10, 0.50 and 1.00) aqueous sodium acetate buffer solutions of pH (1.00 and 12.40) have been investigated at different temperatures, T/K = (298.15-318.15). Densities,  and viscosities, of glycine in water and in aqueous sodium acetate buffer solutions have been measured. The obtained density data have been used to calculate apparent molar volume, , limiting partial molar volume, , limiting partial molar volumes of transfer, . Viscosity B-coefficient, viscosity B-coefficient of transfer, , Activation free energies per mole of the solute,  and solvent,  have been calculated from viscosity data. Further, second order derivative of partial molar expansion coefficient and dependence of coefficients on temperature is useful in measuring the structure making and breaking behavior of solute in these systems. Pair and triplet interaction coefficients for both the properties were also calculated. Thus, the results obtained from volumetric and viscometric studies are of considerable importance to identify different type of interactions (i.e. H-bonding, van der Waal’s interactions)in these systems.