Thermodynamic and physical properties of binary mixtures involving nitrobenzene + the first term of the aliphatic and aromatic nitrile series

Abstract

Jannelli, L., Pansini, M. and Lopez, A., 1983. Thermodynamic and physical properties of binary mixtures involving nitrobenzene + the first term of the aliphatic and aromatic nitrile series. Fluid Phase Equilibria, 15: 219–229. Enthalpies of mixing at 298.16 K, and excess volumes and dielectric constants at temperatures ranging between 293.16 and 333.16 K, have been measured for the binary systems nitrobenzene + acetonitrile and + benzonitrile, over the entire composition range. The benzonitrile and nitrobenzene molecules have very nearly equal volumes and approximately similar shapes; acetonitrile and nitrobenzene are isodielectric. The excess volumes on mixing are negative and the excess enthalpies are positive for both systems; the excess dielectric constants are negative in the case of benzonitrile + nitrobenzene, and positive in the case of acetonitrile + nitrobenzene. Both systems, however, exhibit only small deviations from ideality, extremely small in the case of the benzonitrile + nitrobenzene system. These deviations may be interpreted in terms of only moderate interactions of any kind. nevertheless, the presence of a flat maximum in the excess dielectric constant versus composition curve for acetonitrile + nitrobenzene indicates that interactions between unlike molecules may not be excluded entirely. On the whole, the data collected supply evidence for the supposition that differences in the properties of the pure components should be regarded as the factors which play the most important role in determining deviations from ideality for both systems.