Densities and Viscosities of Amino Acid + Xylitol + Water Solutions at 293.15 ≤ T/K ≤ 323.15

Abstract

Densities (ρ) and viscosities (η) of aqueous xylitol solutions with glycine, l-alanine, l-valine, l-threonine, or l-arginine were measured at T = (293.15 to 323.15) K under atmospheric pressure. The density values were utilized to further calculate the apparent molar volume (Vφ), the limiting partial molar volumes of amino acids (Vφ0), the limiting partial molar volumes of transfer (ΔtrVφ0) and the interaction coefficients Vab, Vabb, Vabbb. The viscosity data were used to obtain viscosity B-coefficient, the free energies of activation per mole of solvent (Δμ10≠) and solute (Δμ20≠). The limiting partial molar volumes of transfer and the free energies of activation per mole of both solvent (Δμ10≠) and solute (Δμ20≠) were analyzed based on the cosphere overlap model and transition state theory, respectively. The hydration number of amino acid was determined using the obtained limiting partial molar volume and viscosity B-coefficient.