The Criterion of Equilibrium Applied to Chemical Reactions

Substituting this definition in Eqs. 4.17 and 4.18, we get the working form of the equilibrium relationship  

For a pure species, such as in Example 4.1, they are the same, but for mixtures they generally are not. 

As we proceed into the study of phase equilibrium, we wiU see that the chemical potential plays the key role. If we knew the chemical potential for every species of every possible chemical mixture in every phase, we would know all there possibly is to know about phase equilibrium and chemical equilibrium. 

Contents are one [diase, in which a chemical reaction occurs 

FIGURE 4.6 An isothermal, constant-pressure container containing only one phase, in which a chemical reaction occurs. 

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