Topological Investigations of Excess Molar Volumes and Excess Isentropic Compressibilities of Ternary Mixtures Containing Pyrrolidin-2-one at 308.15 K

Abstract

Excess molar volumes, ${V^{\rm E}_{ijk}}$, and speeds of sound, u _ijk , of pyrrolidin-2-one (2-Py) (i)+benzene or methyl benzene (j)+propan-1-ol (k) ternary mixtures and speeds of sound, u _ij , of benzene or methyl benzene (i)+propan-1-ol (j) binary mixtures have been measured dilatometrically and interferrometrically over the complete mole fraction range at 308.15 K. Speed-of-sound data have been utilized to evaluate excess isentropic compressibilities for binary and ternary mixtures. ${V^{\rm E}_{ijk}}$ and ${\left({\kappa_S^{\rm E}}\right)_{ijk}}$ values have been fitted to a Redlich–Kister equation to predict ternary adjustable parameters and standard deviations. Topological investigations employed for predicting excess molar volumes and excess isentropic compressibilities, ${\left({\kappa _S^{\rm E}} \right)_{ij}}$, of 2-Py + benzene or methyl benzene or propan-1-ol binary mixtures have been extended to ternary mixtures (by employing the concept of a connectivity parameter of third degree, ³ ξ, of a molecule) to obtain an expression that describes well the measured ${V^{\rm E}_{ijk}}$ and ${\left({\kappa_S^{\rm E}}\right)_{ijk}}$ values.