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How are unbranched alkanes named using IUPAC rules?
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hydrocarbon
Structures assumed by hydrogen (H) and carbon (C) molecules in four common hydrocarbon compounds.
Under the International Union of Pure and Applied Chemistry (IUPAC) rules, unbranched alkanes are named based on the number of carbon atoms in their chain.1
- Small chains: The names methane, ethane, and propane are retained for the first three members of the series.1
- Four carbons: The compound is named butane. Notably, the n- prefix is not used in systematic IUPAC nomenclature for unbranched alkanes.1
- Five or more carbons: Names consist of a Latin or Greek stem indicating the number of carbons, followed by the suffix -ane (e.g., pentane, hexane, heptane).1
These compounds form a homologous series, where each member differs from the previous one by the addition of a group.1