Density, viscosity and refractive index of the dimethyl sulfoxide + o-xylene system

This work reports the experimental results of the densities, viscosities and refractive indices between 298.15 and 323.15 K of the dimethyl sulfoxide + + o-xylene system over the entire composition range of the mixtures. The ex- cess molar volumes (V E ), viscosity deviations (Δν), excess Gibbs energy of ac- tivation of viscous flow (G*E ) and deviations in the refraction (ΔR) were cal- culated from the experimental data; all the computed quantities were fitted to the Redlich-Kister equation. The system exhibits moderate negative values for the investigated excess properties. The resulting excess functions were inter- preted in structural and interactional terms. From the experimental data, the ther- modynamic functions of the activation of viscous flow were estimated. The vis- cosity data were correlated with several semi-empirical equations. The two-pa- rameter McAllister equation can give very good results.