Effect of possible combinations for the different signs of ∆H and ∆S on ∆G
∆G
∆G
∆H –ve and ∆S +ve
∆G always -ve
0 kJ mol-1
0 kJ mol-1
∆H +ve and ∆S -ve
∆G always +ve
T
∆G
T
∆G
0 kJ mol-1
0 kJ mol-1
∆H - ve and ∆S -ve
∆H +ve and ∆S +ve
∆G may be –ve at low
temperatures
∆G may be –ve at high
temperatures
T
© Royal Society of Chemistry 2015
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