Exergonic Reaction
A reaction with a negative Gibbs free energy change, which therefore releases usable energy and proceeds spontaneously.
Formula / equation
ΔG < 0
Unit
kJ/mol
In depth
Exergonic reactions have an equilibrium constant greater than one, so products dominate at equilibrium. In biochemistry they are coupled to unfavourable processes to drive them, most commonly through the hydrolysis of ATP.
Examples in the real world
ATP hydrolysis releasing about 30 kJ/mol; glucose oxidation releasing 2870 kJ/mol.