Homogeneous and Heterogeneous Mixtures

Abstract

In chemistry but also in everyday life, we are very often confronted with mixtures, be they homogeneous or heterogeneous. Think for example of hard liquor, basically a homogeneous mixture of ethanol and water, but also of fog, a heterogeneous mixture of air and minuscule water droplets. First, we concentrate on mixtures made up of two liquid components. We discuss the behavior of the chemical potential of one component in such mixtures and the reason for spontaneous mixing or demixing. For an adequate quantitative description, the concept of chemical potential has to be extended on substances in real solutions by introducing an extra potential $\overset{+}{\mu }.$