Question
From the following values of ∆H and ∆S, decide whether or not these reactions will be spontaneous at 298 K:
Reaction A:
∆H = – 10.5 X 103 J mol–1
∆S = + 31 JK–1 mol–1
Reaction B:
∆H = – 11.7 X 103 J mol–1 ;
∆S = –105 jK–1 mol–1.
Solution
(i) Reaction A:
According to Gibb’s Helmholtz equation,
Since ∆G is –ve, the reaction A will be spontaneous at 298 K.
(ii) Reaction B:
As ∆G is +ve, the reaction B will not be spontaneous at 298 K.
