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Which products form when hydrocarbons burn completely in air?

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structures of common hydrocarbon compounds — hydrocarbon Structures assumed by hydrogen (H) and carbon (C) molecules in four common hydrocarbon compounds.

When hydrocarbons undergo complete combustion in air, they react with oxygen to produce carbon dioxide ( $C O_{2}$ ) and water ( $H_{2} O$ ).1

This process is highly exothermic, meaning it releases heat, which is the fundamental reason why hydrocarbons are widely utilized as fuels. While the specific mechanisms of these reactions are complex and involve various intermediate radicals, the final products of complete oxidation remain consistent for this class of chemical compounds.12