Thus, for an equilibrium such as:formula_13:formula_14Substitute in the expressions for the chemical potential of each reactant::formula_15Upon rearrangement this expression becomes:formula_16The sum formula_17 is the standard free energy change for the reaction, formula_18.
Thus, for an equilibrium such as:formula_23:formula_24Substitute in the expressions for the chemical potential of each reactant::formula_25Upon rearrangement this expression becomes:formula_26The sum formula_27 is the standard free energy change for the reaction, formula_28.