COMBUSTION

rapid chemical reaction between substances that is usually accompanied by generation of heat and light in the form of flame. In most cases, oxygen comprises one of the reactants. Other physical phenomena that sometimes occur during combustion reactions are explosion and detonation. Combustion, one of the most important classes of chemical reaction, is often considered a climax phenomenon in the oxidation of certain types of substances. Although most flames have regions where reduction reactions are important, combustion is primarily the combining of combustible material with oxygen.