Topological investigations of binary and ternary mixtures: excess isentropic compressibilities

The speed of sound, Uij 1,3-dioxolane (D) in binary mixtures (ij) with benzene, cyclohexane, n-hexane or n-heptane and Uijk for 1,3-dioxolane in ternary mixtures (ijk) with the same hydrocarbons have been measured as a function of composition at 298.15 K. The observed data have been utilised to evaluate excess isentropic compressibility of binary, (κsE)ij and ternary (κsE)ijk mixtures using density and speed of sound values of the binary and ternary mixtures. The Moelyn-Huggins concept of interaction between the molecular surfaces of the components of a binary mixture [Polymer 12 (1971) 389] has been extended to evaluate excess isentropic compressibility of the studied binary and ternary mixtures. It has been observed that κsE values predicted by a graph–theoretical approach using connectivities of third degree for binary mixtures compare reasonably well with their corresponding experimental values and κsE for ternary mixtures are of the same sign and order of magnitude.