ABSTRACT
Phase Diagrams .............................................................................. 168
7.1.3 Calculation of Chemical Potential Surfaces .................................. 170
7.1.4 Competing Equilibria: Metastability .............................................. 173
7.1.5 Phase Stability Calculations ........................................................... 174
7.2 The Clausius-Clapeyron Equation ............................................................. 176
7.3 Integration of the Clausius-Clapeyron Equation ....................................... 178
7.3.1 Vaporization and Sublimation Curves ........................................... 181
7.3.2 Phase Boundaries between Condensed Phases .............................. 183
7.4 Triple Points ................................................................................................ 184
7.5 Computer Calculations of ðP; TÞ Unary Phase Diagrams........................... 188
7.6 Alternate Representations of Unary Phase Diagrams................................. 190
7.7 Summary...................................................................................................... 192
In this chapter, the structure of thermodynamics illustrated in Figure 1.4 is
implemented to develop equilibrium maps for unary systems. A system may be
considered to be unary if, for the range of states under study, it may be considered to
consist of a single chemical component. Each of the elements forms a unary system
over its full range of existence. Molecular compounds such as CO
or H
O may be
treated as unary systems over much of the range of temperatures and pressures
normally encountered in the laboratory; under conditions in which they may
decompose to form significant quantities of other molecules, they may not be treated
as unary systems.
