Topological and thermodynamic investigations of binary mixtures: Molar excess volumes, molar excess enthalpies and isentropic compressibility changes of mixing

摘要

Molar excess volumes, V-E, molar excess enthalpies, H-E, and speeds of sound, u, of o-toluidine (i) + cyclohexane or n-hexane or n-heptane (j) binary mixtures have been determined over entire range of composition at 308.15 K. Speeds of sound data have been utilized to predict isentropic compressibility changes of mixing, K-S(E) of (i +j) mixtures. The observed V-E, H-E and K-S(E) data have been analyzed in terms of Graph theory. The analysis of VE data by Graph theory reveals that o-toluidine exists as an associated molecular entity and (i +j) mixtures contain 1: 1 molecular complex. It has been observed that VE, HE and K-S(E) values calculated by Graph theory compare well with their corresponding experimental values. The observed data have also been analyzed in term of Flory theory.