Thermodynamics of molecular interactions in binary mixtures containing associated liquids

Experimentally measured data of excess molar volumes and enthalpies at 308.15 K for binary mixtures of formamide with 1-butanol or 2-methyl-1-propanol were fitted to the Redlich-Kister polynomial equation. Thermodynamics of molecular interaction in these mixtures was discussed using Prigogine-Flory-Patterson theory, Treszczanowicz-Benson association model and Graph theoretical approach. Extent of inter-molecular H-bonding in formamide and butanol in their binary mixtures was also reflected in their molar enthalpy of association of H-bonding ΔhH0 and association constant KH calculated from Treszczanowicz-Benson association model. All the three theories predict the excess property data reasonably well.