AbstractA new model that interrelates the liquid‐phase excess Gibbs energy, enthalpy and volume, called the GHV model, is developed and discussed. The model is based on the fact that most mixtures are immiscible in solid phases and, therefore, have steep solid‐phase boundaries. This single assumption allows the model to be applied potentially to all types of mixtures, including organic, metallic, electrolytic and polymeric solutions. The model, which predicts that excess properties are related to one another through various fusion properties, pure component volumes, and enthalpies of fusion in particular, has been applied to a wide variety of organic and liquid metal mixtures. The results show at least qualitative validity without adjustable parameters and more quantitative ability with “effective” fusion properties. The model is also shown to rationalize some sign, magnitude and shape ph