Studies on the importance of nature of substituent on the thermodynamic and transport properties of liquid mixtures at various temperatures

Abstract

Values of the density (ρ), speed of sound (u), and viscosity (η) are reported for binary mixtures of 3-chloroaniline with substituted benzene derivatives viz., chlorobenzene, bromobenzene and nitrobenzene over the entire composition range of mole fraction at T=(303.15–318.15)K and at atmospheric pressure 0.1MPa. The excess properties such as excess molar volume, excess isentropic compressibility and deviation in viscosity were calculated from the density, speed of sound and viscosity. Excess properties were correlated by the Redlich–Kister equation. The partial molar volumes, partial molar isentropic compressibility, excess partial molar volume and excess partial molar isentropic compressibility were calculated for all the binary systems throughout the composition range and also at infinite dilution. The VE results were analyzed in the light of the Prigogine–Flory–Patterson theory. Analysis of each of the three contributions viz. interactional, free volume and P∗ to VE show that the interactional contribution is positive for all systems, the free volume effect is negative for all the mixtures and the P∗ contribution is negative for all the mixtures except nitrobenzene which shows a positive internal pressure. The variations of these parameters with composition and temperature are discussed in terms of intermolecular interactions prevailing in these mixtures.