Thermodynamic properties of (an alkylbenzene + cyclohexane) at the temperature 298.15 K

Abstract

Excess enthalpies, excess heat capacities, densities, and speeds of sound of (ethylbenzene or 1-methylethylbenzene + cyclohexane) were measured at the temperature 298.15 K. From these measurement, excess volumes, excess isentropic and isothermal compressibilities, and excess isochoric heat capacities were estimated. The excess values are compared with those for (toluene or benzene + cyclohexane). The excess enthalpies and excess volumes are positive and the excess isobaric and isochoric heat capacities are negative for all mixtures. The excess isothermal and isentropic compressibilities are positive along with positive excess volumes. Effects of excess thermal expansivities on isothermal compressibility and isochoric heat capacity are discussed. For these mixtures, the excess thermal expansivity seems to be sufficiently small to be neglected.