Regular solution

The regular solution theory describes a method for the estimation of activity coefficients () in mixtures whose behavior deviates only slightly from Raoult's law. Such solutions are referred to this model as a regular.

Determining equations

For a binary mixture

With

Activity coefficients

Volumes of the pure liquids

Volume fraction

Solubility

Temperature

Gas constant

Enthalpy of vaporization

Summary

With the regular solution theory can be the activity coefficients of the components of a mixture alone determine from the easily accessible pure substance properties, the enthalpy of vaporization and the Lösungssvolumen. It should be noted that a number of simplifications and assumptions severely limit the quality of the prediction.