Volumetric properties of dichloromethane with aniline or nitrobenzene at different temperatures: A theoretical and experimental study

The densities for binary mixtures of dichloromethane with aniline, or nitrobenzene, respectively, including those of pure liquids, were measured over the entire composition range at T = (288.15, 293.15, 298.15, and 303.15) K and atmospheric pressure using a vibrating-tube densimeter. From the experimental results, the excess molar volumes, VmE, partial molar volumes, Vi¯, the apparent molar volume, Vϕi, and the partial molar excess volumes at infinite dilution, (ViE¯)∞, were calculated over whole composition range. Negative values of VmE for (dichloromethane + aniline) attributed to the formation of the charge transfer complex, while for (dichloromethane + nitrobenzene) system, the free volume effect played a dominant role. The extent of negative deviations in VmE values follows the order: nitrobenzene > aniline. The Prigogine–Flory–Patterson (PFP) theory and its applicability in predicting VmE at T = 298.15 K were tested. There is a good agreement in general between the experimental VmE values and those predicted by PFP theory.