For the reaction C2H5OH(l)→C2H4(g)+H2O(g) the enthalpy change is ΔH∘=−75.0kJ mol−1 and the entropy change is ΔS∘=−165J mol−1K−1. At approximately what temperature will the reaction shift from being favored to being unfavored? (Assume both quantities are temperature-independent.)
a) 530K
b) 455K
c) 273K
d) It will be unfavoured at all temperatures because both ΔH∘ and ΔS∘ are negative.