The spontaneity of some reaction can be determined according to the Gibbs free energy change. The formula that connect the Gibbs free energy change and temperature is:
ΔG = ΔH - TΔS
where is: ΔG - the Gibbs free energy change, ΔH - the entalpy change, T - temperature, ΔS - the entropy change.
If, after the calculation for the reaction at the temperature 298 K, the Gibbs free energy change is negative, this reaction is spontaneous.