ABSTRACT

The preceding chapter dealt with the chemical properties of species in single mixture or solution phases. The free energy of a solution or mixture and the chemical potentials of its constituents were quantified. In the present chapter, these properties are applied to determine the phases present and their compositions when a twocomponent system, or binary system, achieves equilibrium. The two components, denoted by A and B, distribute between two phases labeled I and II. This system, shown in Figure 8.1, is at thermal, mechanical, and chemical equilibrium. The first two of these conditions means that the two phases have the same temperature and pressure. The consequence of the last condition is developed in the following section.