Volumetric, viscometric and optical study of molecular interactions in binary mixtures of diethyl malonate with ketones at 303.15, 308.15 and 313.15 K

Density, rho, viscosity, eta, and refractive index, n(D), were measured for binary mixtures of diethyl malonate with ketones (acetophenone, cyclopentanone, cyclohexanone and 3-pentanone) at temperatures of 303.15, 308.15 and 313.15 K over the entire composition range. The excess volume, V-E, deviation in viscosity, Delta eta, excess Gibb's free energy of activation for viscous flow, Delta G(E), and deviation in molar refraction, Delta R, were determined from the experimental data and the computed results were fated to the Redlich-Kister polynomial equation. The values of V-E, Delta eta, Delta G(E), and Delta R were plotted against the mole fraction of diethyl malonate. The observed positive and negative values of the excess parameters for all the studied binary mixtures were explained based on the intermolecular interactions present in these mixtures. Furthermore, different empirical relations were used to correlate the binary mixture viscosities and refractive indices.