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Why does a combustion reaction speed up as its temperature rises?

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The science behind striking a match — combustion Learn about the chemistry of lighting a match.

A combustion reaction speeds up as temperature rises primarily because of the relationship between thermal energy and the activation energy required for a chemical transformation.21

According to the Arrhenius equation, the rate constant of a reaction is expressed as $k = A e^{(- E_{a} / R T)}$ . In this context:21

Thermal Energy: As temperature ( $T$ ) increases, the kinetic energy of the molecules increases.3
Overcoming Barriers: A chemical reaction requires a minimum amount of energy, known as activation energy ( $E_{a}$ ), to convert stable reactants into reactive molecules.41
Reaction Rate: At higher temperatures, a greater fraction of molecules possess sufficient energy to overcome this activation barrier upon collision.21

Consequently, a small increase in temperature leads to a marked increase in the reaction-rate constant, causing the combustion process to accelerate. This acceleration can be significant enough to transition a standard combustion reaction into a thermal explosion.256