Excess enthalpies of binary mixtures of propanediamine+propanediol at 298.15 K

The molar excess enthalpies of 1,2- and 1,3-propanediamine+ 1,2- and 1,3-pr opanediol have been determined at 298.15 K by using a twin-microcalorimeter which requires each component liquid I to 1.5 cm(3) for a series of runs o ver the whole range of mole fraction. All excess enthalpies are exothermic and large. An equilibrium constant K-1 expressed in terms of mole fractions and standard enthalpy of formation of 1:1 complex have been evaluated by i deal mixtures of momomeric molecules and their associated complexes.