|Jmol-3D images||Image 1|
|Molar mass||86.18 g mol−1|
|Density||0.6548 g mL−1|
|Melting point||−96 to −94 °C; −141 to −137 °F; 177 to 179 K|
|Boiling point||68.5 to 69.1 °C; 155.2 to 156.3 °F; 341.6 to 342.2 K|
|Solubility in water||9.5 mg L−1|
|Vapor pressure||17.60 kPa (at 20.0 °C)|
|kH||7.6 nmol Pa−1 kg−1|
|Refractive index (nD)||1.375|
|Viscosity||294 μPa s|
heat capacity C
|265.2 J K−1 mol−1|
|296.06 J K−1 mol−1|
|Std enthalpy of
|−199.4–−198.0 kJ mol−1|
|Std enthalpy of
|−4180–−4140 kJ mol−1|
|GHS signal word||DANGER|
|GHS hazard statements||H225, H304, H315, H336, H373, H411|
|GHS precautionary statements||P210, P261, P273, P281, P301+310, P331|
|EU classification||F Xn N|
|R-phrases||R11, R38, R48/20, R51/53, R62, R65, R67|
|S-phrases||(S2), S16, S29, S33, S36/37|
|Flash point||−26.0 °C; −14.8 °F; 247.2 K|
|Autoignition temperature||234.0 °C; 453.2 °F; 507.1 K|
exposure limit (PEL)
|500 ppm (1800 mg m-3 as an 8 h TWA)|
|LD50||25 g kg−1 (oral, rat)|
|Supplementary data page|
|n, εr, etc.|
Solid, liquid, gas
|Spectral data||UV, IR, NMR, MS|
| (what is: / ?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
The term may refer to any of the five structural isomers with that formula, or to a mixture of them. In 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, odorless when pure, with boiling points between 50 and 70 °C. They are widely used as cheap, relatively safe, largely unreactive, and easily evaporated non-polar solvents.
|Common name||IUPAC name||Text formula||Skeletal formula|
In industry, hexanes are used in the formulation of glues for shoes, leather products, and roofing. They are also used to extract cooking oils (such as canola oil) from seeds, for cleansing and degreasing a variety 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 organolithiums. For example, butyllithiums are typically supplied as a hexane solution.
In many applications (especially pharmaceutical), the use of n-hexane is being phased out due to its long term toxicity. It is often replaced by n-heptane, which will not form the toxic metabolite hexane-2,5-dione.
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.
All alkanes are colourless. 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.
|Isomer||M.P. (°C)||B.P. (°C)|
Normal hexane (n-hexane) has considerable vapor pressure at room temperature:
|Temperature (°C)||Vapor pressure (mmHg)|
Acute exposure to n-hexane usually occurs by inhalation, but it may be absorbed orally and percutaneously. Minor exposures may occur when persons fill their automobiles with gasoline. Recent research suggests that certain fungi may be able to produce n-hexane.
The acute toxicity of n-hexane is rather low. However, it has been reported to be the most highly toxic member of the alkanes. When n-hexane is ingested, it causes nausea, vertigo, bronchial irritation, intestinal irritation and CNS effects. It has been reported that ~ 50 g of n-hexane may be fatal to humans. Furthermore, n-hexane is biotransformed to 2-hexanol and further to 2,5-hexanediol by cytochrome P450 mixed function oxidases by omega oxidation. 2,5-Hexanediol may be further oxidized to 2,5-hexanedione, which is neurotoxic and produces a polyneuropathy.
n-Hexane is also used as a solvent in the extraction of oil from seeds (soybean, cottonseed, flaxseed, safflower seed, and others). It is sometimes used as a denaturant for alcohol, and as a cleaning agent in the textile, furniture, and leather industries. It is slowly being replaced with other less toxic solvents.
The National Institute for Occupational Safety and Health recommended exposure limit is 50 ppm (180 mg m-3), expressed as an 8 h time-weighted average (TWA).
Poisoning from touchscreen cleaner
In February 2010, reports surfaced saying that an employee of Wintek Corporation, an Apple contractor in China, a company that manufactures iPhone touchscreen components, died in August 2009 due to hexane poisoning. Hexane was used as a replacement for alcohol for cleaning the screens. Reports suggest up to 137 Chinese employees required treatment for hexane poisoning around the same time. An ABC Foreign Correspondent episode covertly interviewed several women who had been in the hospital for over six months. The women said that they were exposed to hexane while manufacturing iPhone hardware. Apple has since required Wintek and other suppliers to cease using hexane.
- "n-hexane – Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 16 September 2004. Identification and Related Records. Retrieved 31 December 2011.
- "C5 and C6 alkanes". A and B Scott Organic Chemistry. Retrieved 30 October 2007.
- Use of ozone depleting substances in laboratories. TemaNord 2003:516.
- "Organic Chemistry-I" (PDF). Retrieved 2014-02-17.
- "13. Hydrocarbons | Textbooks". Textbook.s-anand.net. Retrieved 2014-02-17.
- William D. McCain (1990), The properties of petroleum fluids. PennWell. ISBN 0-87814-335-1
- vapor pressure
- Stephen R Clough; Leyna Mulholland (2005), "Hexane", Encyclopedia of Toxicology 2 (2nd ed.), Elsevier, pp. 522–525
- Silicon Sweatshops: Another black eye for Apple supplier Global Post, 25 February 2010
- Workers poisoned while making iPhones ABC News, 25 October 2010
-  Apple Supplier Responsibility
- International Chemical Safety Card 1262 (2-methylpentane)
- Material Safety Data Sheet for Hexane
- National Pollutant Inventory – n-hexane fact sheet
- NIOSH Pocket Guide to Chemical Hazards (hexane isomers)
- Phytochemica l database entry
- Center for Disease Control and Prevention
- Warning from National Safety Council "COMMON CHEMICAL AFFECTS AUTO MECHANICS"
- Australian National Pollutant Inventory (NPI) page
- "EPA does not consider n-hexane classifiable as a human carcinogen." Federal Register / Vol. 66, No. 71 / Thursday, 12 April 2001 / Rules and Regulations