7. Glossary

Réaction élémentaire; elementary reaction

A reaction that takes place in a single step and involves no reaction intermediates. At most, it involves the destruction and formation of two or three chemical bonds. An elementary reaction obeys a speed law whose partial orders correspond to the reaction's stoichiometry and the principle of micro-reversibility.

Porteur de chaîne; chain carrier

An unstable or metastable chemical species that propagates and sustains overall reactivity through its various reactions with initial reactants or reaction intermediates. Chain carriers are essentially atoms and radicals, of which the most important for combustion are ${\text{H}}^{·}$ ,