Topological investigations of excess heat capacities of binary liquid mixtures containing lactams and cycloalkanone

The excess heat capacities, CPE, of binary 1-Methylpyrrolidin-2-one or pyrrolidin-2-one (i) + cyclopentanone or cyclohexanone or cycloheptanone or cyclohexane (j) mixtures were obtained over the entire mole fraction range using micro-differential scanning calorimeter (Model - μDSC 7 Evo) in the temperature range from 293.15 to 308.15 K at atmospheric pressure. The observed data have been fitted to Redlich-Kister equation to calculate adjustable parameters and standard deviations. The Moelwyn-Huggins concept of interactions between the components of mixture has been utilized using the topology of the constituent molecules (Graph theory) to determine excess heat capacities, CPE of the studied mixtures. The results obtained indicate that CPE values calculated by Graph theory are in agreement with experimental values.