PARAMETERS
−100
+50
298 K
RESULTS
ΔH
TΔS
ΔG = ΔH − TΔS
4 ΔH/ΔS COMBINATIONS
ΔH<0, ΔS>0
Always spontaneous
ΔG always < 0
Always spontaneous
ΔG always < 0
ΔH>0, ΔS>0
Spontaneous at
high T
Spontaneous at
high T
ΔH<0, ΔS<0
Spontaneous at
low T
Spontaneous at
low T
ΔH>0, ΔS<0
Never spontaneous
ΔG always > 0
Never spontaneous
ΔG always > 0
Units reminder:
ΔH in kJ mol⁻¹
ΔS in J mol⁻¹ K⁻¹
TΔS = T(K) × ΔS/1000 kJ
ΔG < 0 → spontaneous
ΔG = 0 → equilibrium
ΔG > 0 → non-spontaneous
ΔH in kJ mol⁻¹
ΔS in J mol⁻¹ K⁻¹
TΔS = T(K) × ΔS/1000 kJ
ΔG < 0 → spontaneous
ΔG = 0 → equilibrium
ΔG > 0 → non-spontaneous