The Alkanes Are one of the different types of hydrocarbons found in crude oil. Hydrocarbons are compounds made of carbon and hydrogen atoms linked by covalent bonds (BBC, 2014).
Hydrocarbons containing only single bonds are called alkanes. They are called saturated hydrocarbons because there is a hydrogen in each possible location. This gives them a general formula C N H 2n + 2 (Alkanes, S.F.).
Alkanes can be subdivided into the following three groups: straight chain alkanes, branched alkanes and cycloalkanes (Alkanes, 2016).
Alkanes are also saturated hydrocarbons, ie they do not contain double or triple bonds, which are highly reactive in organic chemistry.
Alkanes are the simplest and least reactive hydrocarbon species containing only carbons and hydrogens. They are commercially very important, being the main constituent of gasoline and lubricating oils and are widely used in organic chemistry (Khan Academy, S.F.).
The role of pure alkanes (such as hexanes) is mainly delegated in solvents. Although not totally devoid of reactivity, their lack of reactivity in most laboratory conditions makes them a relatively uninteresting, though very important component of organic chemistry.
The energy confined within the carbon-carbon bond and the carbon-hydrogen bond is quite high and its rapid oxidation produces a lot of heat, typically in the form of fire.
The names of all alkanes end with -an whether linear or contain side chains and branches, the name of each carbon-hydrogen chain that lacks double bonds or groups. If the carbons are linked together in a ring they are called cycloalkanes.
Examples of alkanes
1- Linear Alkanes
Methane : It is a colorless and odorless gas produced abundantly in nature and as a product of certain human activities. Methane is the simplest member of alkanes and is among the most potent of the greenhouse effect (Encyclopædia Britannica, 2017).
Ethane : Is a gas that is mainly found in natural gas and is used in mixtures with other gases to produce fuels.
Propane : It is a colorless gas, which is found in natural gas and is used as fuel in homes and industries. The chemical formula of propane is C 3 H Referring to Fig. And is extended formula is CH 3 CH 2 CH 2 (Propane Formula, S.F).
Butane : Or n-butane is one of dozens of gases extracted from natural gas and can also be produced from crude oil. N-butane is a multipurpose colorless gas. Butane can be used for heating, cooling and fuel for lighters.
N-pentane : Is a clear colorless liquid with a petroleum-like odor. Pentane is found in alcoholic beverages and in hop oil. This alkane is a component of some fuels and is used as a specialty solvent in the laboratory.
N-hexane : Is a clear colorless liquid with a petroleum-like odor. It is found in citrus fruits and is used to extract edible oils from seeds and vegetables, as a solvent for special use, and as a cleaning agent.
N-heptane : It is a clear colorless liquid with an odor similar to that of petroleum. It is found in cardamom. Less dense than water and insoluble in water. Vapors heavier than air.
N-octane : Is a colorless liquid with a gasoline odor. Less dense than water and insoluble in water. So it floats in the water. It produces irritating vapor.
Methyl Chloride : Also called chloromethane, is a colorless gas. It is the simplest haloalkane, used in the manufacture of silicone polymers and in the manufacture of other chemicals.
Chloroform : Is a colorless, odorous and highly volatile liquid that has been widely used for its anesthetic properties. Because of these properties, it has the reputation of being able to stun or hit people, even when consumed in small doses (MoviesDoes Chloroform Really Knock You Out As Quickly As They Show In Movies?, 2016).
Carbon tetrachloride : Also called tetrachloromethane, a colorless, dense, highly toxic, volatile, nonflammable liquid that has a characteristic odor and is used as a solvent.
Chloroethane : Is a gas that condenses under a slight pressure. Chloroethane is mainly used to relieve local pain in sports medicine (National Center for Biotechnology Information., 2017).
Bromoethane : Also known as ethyl bromide, is a colorless volatile liquid, slightly soluble and denser than water. Vapors are heavier than air. It is used to make pharmaceuticals and as a solvent.
2- Branched alkanes
Isobutane : It is a colorless gas with a faint odor of oil. It is sent as a liquefied gas under its vapor pressure. Contact with liquid may cause frostbite. It turns on easily.
Isopentane : Also called 2 methylbutane, is a colorless aqueous liquid with a gasoline odor. Floats in the water. Inflammable and irritating vapor is produced (National Center for Biotechnology Information, PubChem Compound Database, 2017).
2-methylpentane : Is a branched chain alkane of the molecular formula C 6 H1 4 . It is an aqueous liquid with a gasoline odor that floats on water and produces an irritating vapor.
3,3-Dimethylhexane : It is found in herbs and spices. 3, 3-Dimethylhexane is a component of the oil of Osmanthus fragrans (osmanthus sweet) and ginseng.
2,3-Dimethylhexane : Is found in fruits. 2,3-Dimethylhexane is a volatile component of starch.
Neopentano : Is a liquid less dense than water. Insoluble in water but soluble in alcohol (National Center for Biotechnology Information, 2015).
2,2,4-trimethylpentane : Or isooctane is released into the environment by the manufacture, use and disposal of products associated with the petroleum industry. 2,2,4-trimethylpentane penetrated the skin of a human and caused necrosis of the skin and tissue in the hand, required surgery (National Center for Biotechnology Information., 2017).
3-Cycloalkanes
Cyclopropane : Is a colorless gas with an oil-like odor. Contact with liquid may cause frostbite. It can suffocate by the displacement of the air and has a narcotic effect in high concentration.
Cyclobutane : Gas that condenses to a liquid at 13 ° C. Insoluble in water. Soluble in alcohol, acetone and ether.
Cyclopentane : Is a clear colorless liquid with a petroleum-like odor. Less dense than water and insoluble in it. Vapors are heavier than air.
Cyclohexane : Is located in kohlrabi. Diluent in mixtures of color additives for food use.
Cycloheptane : Is a colorless oily liquid, insoluble and less dense than water. Inhalation of high concentrations may have a narcotic effect. It is used to make other chemicals.
Cyclooctane : Is a polycyclic hydrocarbon of nine carbon atoms. Insoluble in water.
Methylcyclohexane : Is a clear colorless liquid with a petroleum-like odor. In methylcyclohexane, the conformation of the chair in which the large methyl group is equatorial is the most stable and, therefore, the most populated of all possible conformations (Carey, 2011).
Isopropyl cyclohexane : Is a colorless liquid found in fruits. Isopropyl cyclohexane is found in Carica papaya (papaya).
Methylcyclopentane : Is a colorless liquid that is insoluble and less dense than water. Vapors may be narcotic and irritant. Methylcyclopentane is isolated from Helianthus annuus (sunflower).
Norborano : Is a bicyclic alkane also called bicyclo [2,2,1] heptane of the formula C7H12.
References
- Alkanes . (2016, November 28). Retrieved from chem.libretexts.org.
- Alkanes . (S.F.). Retrieved from hyperphysics.phy-astr.gsu.edu.
- (2014 ). Alkanes . Retrieved from bbc.co.uk.
- Carey, F. A. (2011, December 2). Hydrocarbon . Recovered from Britannica.
- Encyclopædia Britannica. (2017, March 24). Methane . Retrieved from britannica.com.
- Khan Academy. (S.F.). Alkanes, cycloalkanes, and functional groups . Retrieved from khanacademy.org.
- MoviesDoes Chloroform Really Knock You Out As Quickly As They Show In Movies? (2016). Recovered from scienceabc.
- National Center for Biotechnology Information. . (2017, May 06). PubChem Compound Database; CID = 6337 . Recovered from PubChem.
- National Center for Biotechnology Information. (2015, May 6). PubChem Compound Database; CID = 10041 . Recovered from PubChem.
- National Center for Biotechnology Information. (2017, May 6). PubChem Compound Database; CID = 10907 . Recovered from PubChem.
- National Center for Biotechnology Information. PubChem Compound Database; (2017, May 6). PubChem Compound Database; CID = 6556, . Recovered from PubChem.
- Propane Formula . (S.F.). Recovered from softschools.com.