Journal of Chemical and Engineering Data, Vol.50, No.1, 6-10, 2005
Thermodynamic investigation of the azeotropic binary mixture water plus n-propanol
Molar heat capacities of the azeotropic mixture in the binary system {water (x = 0.568) + n-propanol (x = 0.432)} were measured with an adiabatic calorimeter in the temperature range from (80 to 320) K. The functions of the heat capacity with respect to the thermodynamic temperature were established. A glass transition was observed at 102.037 K. The solid-liquid-phase transition of the azeotropic mixture took place in the temperature range from (237.075 to 262.424) K. The corresponding enthalpy and entropy of the solid-liquid-phase transition were calculated to be 5.869 kJ.mol(-1) and 22.73 J.K(-1.)mol(-1), respectively. The thermodynamic functions and the excess thermodynamic functions of the azeotropic mixture relative to a temperature of 298.15 K were derived on the basis of the relationships of the thermodynamic functions and the function of the measured heat capacity with respect to temperature.