CHEMISTRY · Single correct · A Level · Chemistry · Thermodynamics · Thermodynamics
Problem
A reaction has ΔH > 0 and ΔS > 0. Which statement best describes its thermodynamic favorability?
(a) It is non-spontaneous at all temperatures because the positive ΔH always opposes spontaneity.
(b) It becomes spontaneous only at sufficiently high temperatures because TΔS eventually outweighs ΔH.
(c) It is spontaneous at all temperatures because the positive ΔS term always drives ΔG negative.
(d) It is spontaneous only at low temperatures because the TΔS term is then small compared with ΔH.