Final answer:
The standard Gibbs energy of reaction can be expressed in terms of the standard Gibbs energy of formation (ΔG°f) of reactants and products. It is calculated by subtracting the sum of the standard Gibbs energies of the reactants from the sum of the standard Gibbs energies of the products.
Step-by-step explanation:
The standard Gibbs energy of reaction can be expressed in terms of the standard Gibbs energy of formation (ΔG°f) of reactants and products. The standard Gibbs energy of formation is the change in free energy that occurs when one mole of a substance is formed from its elements in their standard states. It is denoted by AG°f and is normally found directly from tables.
Using Equation 14.3.8, the standard Gibbs energy of reaction (AG°) can be determined by subtracting the sum of the standard Gibbs energies of the reactants (ΣAG°) from the sum of the standard Gibbs energies of the products (ΣAG°):
AG° = ΣAG°(products) - ΣAG°(reactants)
Tables of thermodynamic values, such as Table T2, provide AG° values for common substances, which can be used to calculate AG° for a given reaction.