octane

chemical compound

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June 18, 2026

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Octane is a chemical compound that is part of the alkane family, with the molecular formula C₈H₁₈. It is a hydrocarbon, meaning it is composed solely of carbon and hydrogen atoms. Octane is used as a reference fuel in the octane rating system, which measures a fuel's ability to resist knocking when ignited in an internal-combustion engine.12

Specifically, octane is one of two reference fuels used to determine a fuel's octane number. The other is heptane, which knocks readily. The octane number of a fuel is determined by comparing its knock intensity to that of blends of octane and heptane. Higher octane numbers indicate a greater resistance to knocking. This property is crucial for the efficient and safe operation of automobile engines.234

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butene
…utilized for the production of octanes, which are important constituents of gasoline. This is done either by causing the butenes to react with isobutane or by dimerizing (combining two molecules of) butenes to form octenes, which, on hydrogenation (addition of hydrogen atoms to molecules), yield octanes. On treatment with water…
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…utilized for the production of octanes, which are important constituents of gasoline. This is done either by causing the butenes to react with isobutane or by dimerizing (combining two molecules of) butenes to form octenes, which, on hydrogenation (addition of hydrogen atoms to molecules), yield octanes. On treatment with water…
Read More