Hexane

Isomers and nomenclature

There are five structural forms of hexane (constitutional isomers). By systematic naming, the unbranched straight‑chain form is the one officially called "hexane" (often written n‑hexane). Other isomers have distinct names. The term IUPAC assigns names so that each structural variant is unambiguous.

• n‑Hexane (straight chain)
• 2‑Methylpentane (isohexane)
• 3‑Methylpentane
• 2,3‑Dimethylbutane
• 2,2‑Dimethylbutane

Physical and chemical properties

Hexane is a colorless, volatile liquid at room temperature. It is largely nonpolar, immiscible with water, and dissolves many organic substances. Compared with water it is less dense and has a relatively low boiling point, which makes it useful as an easily removed solvent. As a saturated hydrocarbon, hexane is relatively unreactive under ordinary conditions but will burn in air and can undergo typical alkane reactions such as halogenation under appropriate conditions.

Production and common uses

Most commercial hexane is obtained from petroleum refining and natural gas processing as part of light naphtha fractions. It is widely used as an industrial solvent in paints, adhesives, rubber and leather processing, and in laboratories. One notable application is the extraction of edible oils from seeds and vegetables, where hexane's solvent properties are valued. Hexane and its isomers also appear as components of automotive and aviation fuels.

Health, safety and environmental considerations

Hexane is highly flammable and should be handled away from heat and ignition sources. Chronic inhalation of primarily n‑hexane has been associated with peripheral nerve damage in occupational settings; therefore good ventilation, exposure controls and personal protective equipment are recommended. As a volatile organic compound it can contribute to air pollution and photochemical smog if released in large amounts. Safer substitutes or tightly controlled processes are increasingly used where possible.

Notable distinctions

Practically, "hexane" on a product label often denotes a mixture of C6 hydrocarbons rather than the pure straight‑chain isomer; when toxicity, reactivity or legal compliance matters, the exact composition should be checked. For technical data, handling guidance and regulatory details consult specific material safety resources or industry references linked above.