Unit 9.2: Absolute Entropy and Entropy Change

Calculate the entropy of a system given the entropies of component species using ∆S°rxn = ∑∆S°prod - ∑∆S°react.

• Calculate ∆S°rxn for the combustion of methane: CH₄(g) + 2O₂(g) → CO₂(g) + 2H₂O(g).
• Why is it necessary to account for stoichiometric coefficients in ∆S°rxn calculations?