What is Hexane?

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Molecular structure of Hexane

Hexane is an organic compound (hydrocarbon) made of the elements carbon and hydrogen. Hexane is an unbranched isomer (n-hexane). A compound that exists in forms having different arrangements of atoms but the same molecular weight is known as isomer.  Hexanes are significant constituents of gasoline.  Hexane is widely used as a cheap, relatively safe, largely unreactive, and easily evaporated non-polar solvents. Gasoline is a petroleum-derived liquid mixture which is primarily used as a fuel in internal combustion engines. A liquid solvent without significant partial charges on any atoms, as in the hydrocarbons, or where the polar bonds are arranged in such a way that the effects of their partial charges cancel out is known as non-polar solvent.


What are the Properties of Hexane?

Hexane’s physical properties are eminent.

  • The molecular formula of hexane is C6H14.
  • It is mostly a colorless liquid.
  • It has a melting point of roughly -139.54°F (-95.3°C) and
  • The boiling point is 154.04°F (67.8°C).
  • It has a molar mass of 86.18 grams per mole (g/mol).
  • It is also a non-polar molecule, meaning that it is not soluble in water.


What is the structure of hexane?

Hexane is an “alkane” with six carbon atoms. Alkanes (also known as paraffin or saturated hydrocarbons) are chemical compounds that consist only of the elements carbon (C) and hydrogen (H) (i.e., hydrocarbons), wherein these atoms are linked together exclusively by single bonds. Hexane is a quite simple molecule. As the “hex” prefix indicates, it has six carbon atoms. These carbon atoms are accompanied by 14 hydrogen atoms, giving it the molecular formula C6H14. The carbons are chained in a row, one following the next. Each carbon has at least two hydrogen atoms attached to it, except for the first and last carbon that have three.


How is Hexane produced?

Hexanes are mainly got by the refining of crude oil (naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons). The exact composition of the fraction depends largely on the source of the oil (crude or reformed) and the restraint of the refining. The industrial product (usually around 50% by weight of the straight-chain isomer) is the fraction boiling at 65–70 °C.


What are the uses of Hexane?

  • The most excellent use of hexane is its function as a solvent.
  • Many types of plants and vegetables are treated with hexane in order to extract their oils and proteins for use in other products. Produce treated include soybeans, peanuts, and corn.
  • Hexane is also used as a cleaning solvent and as an industrial degreaser.


What is the Downside of hexane?

  • The downside of hexane due to its role in oil and protein extraction has been linked to debate. Many of the products utilize oils and proteins extracted through the use of hexane. These products include baby formula, alternative vegetarian foods, and protein shakes. Some of these products even declare to be natural or healthy alternatives. Health groups had samples tested of the industrial products extracted using hexane, and has been found that some residue remained at the parts-per-million (ppm) level. Though, some people consider this to be a safe level, some people are not comfortable.
  • Hexane can enter our body through the lungs if it is in the air we breathe. It can also enter the body through the stomach and intestines if it is in the drinking water or food.
  • Once hexane is inhaled it goes into the bloodstream and is carried to all the organs in your body. Enzymes in your liver break down hexane. If you are exposed to high concentrations of hexane over a long period, one of these broken down products may cause damage to your nervous system.
  • In a group of workers in Japan, it was estimated that the workers who became ill had been breathing air containing 500-2,500 parts hexane per million parts air (500-2,500 ppm) for 8-14 hours a day for 6 months to several years. The first symptom that the affected workers had was a feeling of numbness in their feet and hands. This was followed by muscle weakness in the feet and lower legs. If exposure continued, the symptoms grew worse. Sniffing products containing hexane has caused paralysis of the arms and legs in teenagers in the United States and Europe.


How to reduce the risk of exposure to hexane?

Some products used in the home may contain hexane, for instance, some quick-drying glues and cements used in hobbies. These products should be kept out of the reach of children and only used with proper ventilation.


What are the health regulations related to hexane?

  • OSHA, the Occupational Safety and Health Administration have set a Permissible Exposure Limit (PEL) of 500 ppm for hexane in place of work.
  •  A court judgment struck down a proposed PEL of 50 ppm.
  •  Damage to nerves has been found in people at 500 ppm.
  •  American Conference of Governmental Industrial Hygienists (ACGIH) recommends a Threshold Limit Value (TLV) of 50 ppm.
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