What is Gibbs Free Energy?
Gibbs free energy (G) is a thermodynamic function that determines whether a reaction is spontaneous under constant temperature and pressure.
It is given by the equation:
ΔG = ΔH - TΔS
ΔG is the Gibbs free energy change
ΔH is the enthalpy change
T is the temperature in Kelvin
ΔS is the entropy change.
A reaction is thermodynamically feasible if ΔG < 0 (negative), meaning it can occur without external energy input. Even if ΔG is negative, the reaction may still be slow due to a high activation energy. Understanding Gibbs free energy is essential in A Level Chemistry for predicting reaction feasibility and exploring entropy, enthalpy, and equilibrium concepts.
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