CPE - Excess Heat Capacities, Mixture Heat Capacities

Excess heat capacities in most cases contribute only little to the heat capacity of a mixture but should nevertheless be considered if very precise results are required. In addition, the data bank also contains data for the total heat capacity of a mixture.

DDB-CPE is of great use for the regression of temperature dependent model parameters for gE-models and equations of state as it supplies reliable information about the temperature dependence of the excess enthalpy.

Excess heat capacities therefore provide information about the second derivative of gE and thus the activity coefficients with respect to 

The figure on the right shows the excess heat capacity for the well known system ethanol-water as function of liquid mole fraction for three different temperatures.

A full list of systems is available in our DDB Online Search system. The page might take some seconds to load because of its size.


Selected Scientific Papers

1988    Thermodynamic Properties of Ethanol and Water. III. Description of the Different Excess Functions (gE,hE,cpE) Using an Empirical Model    Gaulhofer A., Kolbe B., Gmehling J.    Journal    Fluid Phase Equilib., 39, 3, 193 209 (1988)
1985    Thermodynamic Properties of Ethanol + Water. II. Potentials and Limits of gE Models    Kolbe B., Gmehling J.    Journal    Fluid Phase Equilib., 23, 3, 227 242 (1985)