8: Phase Transitions and Equilibria of Pure Substances

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Page ID: 20409

Howard DeVoe
University of Maryland

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A system of two or more phases of a single substance, in the absence of internal constraints, is in an equilibrium state when each phase has the same temperature, the same pressure, and the same chemical potential. This chapter describes the derivation and consequences of this simple principle, the general appearance of phase diagrams of single-substance systems, and quantitative aspects of the equilibrium phase transitions of these systems.

8.1: Phase Equilibria
8.2: Phase Diagrams of Pure Substances
A phase diagram is a two-dimensional map showing which phase or phases are able to exist in an equilibrium state under given conditions. This chapter describes pressure–volume and pressure–temperature phase diagrams for a single substance.
8.3: Phase Transitions
8.4: Coexistence Curves
8.5: Chapter 8 Problems

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