9.2 Absolute Entropy and Entropy Change

Calculate the standard entropy change for a chemical or physical process based on the absolute entropies (standard molar entropies) of the species involved in the process.

• The entropy change for a process can be calculated from the absolute entropies of the species involved before and after the process occurs. EQN: ΔSo reaction = ΣSo products − ΣSo reactants