thumb|The [[thermite reaction is famously exothermic. The reduction of iron(III) oxide by aluminium releases sufficient heat to yield molten iron.]]
In thermochemistry, an exothermic reaction is a "reaction for which the overall standard enthalpy change ΔH⚬ is negative." Exothermic reactions usually release stored energy as heat. The term is often confused with exergonic reaction, which IUPAC defines as "... a reaction for which the overall standard Gibbs energy change ΔG is negative."
See also
- Chemical thermodynamics
- Differential scanning calorimetry
- Endergonic
- Exergonic
- Endergonic reaction
- Exergonic reaction
- Exothermic process
- Endothermic reaction
- Endotherm