Science & Environment
Gibbs Free Energy Spontaneity Calculator
Calculate Gibbs free energy change (dG = dH - TdS) to determine whether a reaction is spontaneous.
Your inputs
Change any value to update the result instantly.
Gibbs free energy ΔG
-85.1 kJ/mol
Spontaneity
1 Spontaneous
TΔS term
-14.9 kJ/mol
Temperature used
298 K
Formula and working
ΔG = ΔH − TΔS
- 1
Collect the inputs
Enthalpy change ΔH = -100 kJ/mol; Entropy change ΔS = -50 J/(mol·K); Temperature = 298 K
- 2
Apply the formula
ΔG = ΔH − TΔS
- 3
Result
Gibbs free energy ΔG = -85.1 kJ/mol
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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