Study on thermophysical properties in the ternary mixture of N-methylglycine solute with (d-glucose + water) binary solvent at temperatures of 298.15, 308.15, and 318.15 K

Abstract

Density, speed of sound and refractive index data were measured to eight molal concentrations of N-Methylglycine in aqueous d-Glucose for mixed ternary solutions. The molality of N-methylglycine solute is between 0.3140 and 1.2005 mol·kg−1 in 0.2052, 0.4201, 0.6455, and 0.8824 mol·kg−1 aqueous d-glucose solvent at temperatures of 298.15, 308.15, and 318.15 K and at atmospheric pressure. The relation between experimental data of refractive index and density has been good correlated with several empirical and semi-empirical equations like Lorentz–Lorenz, Dale–Gladstone, Eykman, Oster, Arago–Biot, Newton and Modified–Eykman. As well, the derived thermophysical properties as the apparent molar volumes, the standard partial molar volume, standard partial molar volumes of transfer from water to (d-glucose + H2O) solutions, isentropic compressibility coefficient, the estimation of the isentropic compressibility at infinite dilution, and solvation number were calculated from measured values of densities and speeds of sound. Finally, the molar refractivity in ternary mixture was computed using Lorentz-Lorenz equation. The influence of the amino acid and carbohydrate concentration on the thermophysical properties has been evidenced. The obtained values were interpreted in terms of solute-cosolute and solute-solvent interactions present in the studied aqueous mixtures.