Basic Criteria for Chemical Equilibrium of Reacting Systems

1 I Basic Criteria for Chemical Equilibrium of Reacting Systems 

The basic criterion for equilibrium with a single reaction is  

In general it is not true that the change in the standard Gibbs function, AG, is zero. Thus, 

Application of Equation (A. 1.6) to Equation (A. 1.7) and recalling that AG = 0 at equilibrium gives  

Note that AG° = A//° — TAS, where A// and AA° are the standard enthalpy and entropy, respectively, and differentiation of this expression with respect to T gives  

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