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

• Thermophysical properties of 3-chloroaniline with isomeric chlorobenzenes were studied at various temperatures.
• Excess properties were correlated with Redlich–Kister equation.
• The effect of temperature on density and speed of sound were discussed in term of intermolecular interactions.
• Experimental VmE were successfully correlated using the PFP model.

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 0.1 MPa. 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.

Excess molar volumes of the binary mixtures against mole fraction x1 at T = 303.15 K for 3-chloroaniline + bromobenzene (■), 3-chloroaniline + chlorobenzene (●), 3-chloroaniline + nitrobenzene (▲) and (---) calculated with PFP theory using parameters.Figure optionsDownload as PowerPoint slide