Chemistry A-Level
Gibbs equation and free energy change
What Gibbs equation and free energy change means in Chemistry A-Level, as defined for OCR.
Definition of Gibbs equation and free energy change
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Reference: OCR
The free energy change, ∆G, is calculated as ∆G = ∆H – T∆S, where ∆H is the enthalpy change, ∆S the entropy change and T the temperature in kelvin.
Topics that use Gibbs equation and free energy change
- Enthalpy and entropy (OCR A-Level)
Related terms
- Activation energy and reaction rate
- Comparison of solid, liquid and gas
- Entropy change and the T∆S term
- Entropy of the system
- Feasibility and the sign of ∆G
- Freedom of motion of particles in each state
- Gibbs free energy and feasibility
- Number of accessible microstates in each state
Using Gibbs equation and free energy change in the exam
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