Solute–solvent and solvent–solvent interactions of menthol in isopropyl alcohol and its binary mixtures with methyl salicylate by volumetric, viscometric, interferometric and refractive index techniques

The apparent molar volume (V∅), viscosity B-coefficient, isoentropic compressibility (ϕK) of menthol have been determined in binary solution of isopropyl alcohol and methyl salicylate (at 303.15, 313.15 and 323.15 K) from density (ρ), viscosity (η) and sound speed respectively. The apparent molar volumes have been extrapolated to zero concentration to obtain the limiting values at infinite dilution using Masson equation. The infinite dilution partial molar expansibilities have also been calculated from the temperature dependence of the limiting apparent molar volumes. Viscosity B  -coefficients has been calculated using Jones–Dole equation. The structure-making or breaking capacity of the solute under investigation has been discussed in terms of sign of (δ2VØo/δT2)P. The activation parameters of viscous flow were determined and discussed by application of transition state theory.