−95 °C (178 K)
69 °C (342 K)
Hexane is a hydrocarbon with the chemical formula C6H14; that is, an alkane with six carbon atoms.
The term may refer to any of four other structural isomers with that formula, or to a mixture of them. In the IUPAC nomenclature, however, hexane is the unbranched isomer (n-hexane); the other four structures are named as methylated derivatives of pentane and butane. IUPAC also uses the term as the root of many compounds with a linear six-carbon backbone, such as 2-methylhexane C7H16, which is also called "isoheptane".
Hexanes are significant constituents of gasoline. They are all colorless liquids at room temperature, with boiling points between 50 and 70 °C, with gasoline-like odor. They are widely used as cheap, relatively safe, largely unreactive, and easily evaporated non-polar solvents.
In industry, hexanes are used in the formulation of glues for shoes, leather products, and roofing. They are also used to extract cooking oils from seeds, for cleansing and degreasing all sorts of items, and in textile manufacturing.
A typical laboratory use of hexanes is to extract oil and grease contaminants from water and soil for analysis. Since hexane cannot be easily deprotonated, it is used in the laboratory for reactions that involve very strong bases, such as the preparation of Grignard reagents.
Hexanes are chiefly obtained by the refining of crude oil. The exact composition of the fraction depends largely on the source of the oil (crude or reformed) and the constraints of the refining. The industrial product (usually around 50% by weight of the straight-chain isomer) is the fraction boiling at 65–70 °C.
The boiling points of the various hexanes are somewhat similar and, as for other alkanes, are generally lower for the more branched forms. The melting points are quite different and the trend is not apparent.
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