Select the correct statements: I. 12 g O₂ can completely react with 13.5 g Al to form Al₂O₃. II. Under ideal stoichiometric conditions, actual yield does not exceed theoretical yield. III. 1 mol C₃H₈ and 1 mol C₃H₄ each produce 3 mol CO₂ on complete combustion. IV. 1 g S combines with 1 g O₂ to produce 1 g SO₂.