Standard Gibbs Free-Energy Change for Chemical Reactions

Standard Gibbs Free-Energy Change for Chemical Reactions 

In chemical thermodynamics, the process of frequent interest is the chemical reaction, abbreviated as  

The change in the GFE for a finite amount of reaction at constant T and P may be written as  

In principle, values of U, H, and S, from which G may be calculated, exist for each chemical species. If these values could be determined, then the change in the GFE could be calculated for the reaction as follows  

Any reaction between elements to form compounds has associated with it a change in the GFE between the compound and the reactant elements. Thus, for the oxidation of iron at T  

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