Not to be confused with alkene, alkyne, alkali, or alkaline.
Chemical structure of methane, the simplest alkane
In organic chemistry, an alkane, or paraffin (a historical trivial name that also has other meanings), is an acyclic saturated hydrocarbon. In other words, an alkane consists of hydrogen and carbon atoms arranged in a tree structure in which all the carbon–carbon bonds are single.[1] Alkanes have the general chemical formula CnH2n+2. The alkanes range in complexity from the simplest case of methane (CH4), where n = 1 (sometimes called the parent molecule), to arbitrarily large and complex molecules, like pentacontane (C50H102) or 6-ethyl-2-methyl-5-(1-methylethyl) octane, an isomer of tetradecane (C14H30).
The International Union of Pure and Applied Chemistry (IUPAC) defines alkanes as "acyclic branched or unbranched hydrocarbons having the general formula CnH2n+2, and therefore consisting entirely of hydrogen atoms and saturated carbon atoms". However, some sources use the term to denote any saturated hydrocarbon, including those that are either monocyclic (i.e. the cycloalkanes) or polycyclic, despite their having a distinct general formula (i.e. cycloalkanes are CnH2n).
In an alkane, each carbon atom is sp3-hybridized with 4 sigma bonds (either C–C or C–H), and each hydrogen atom is joined to one of the carbon atoms (in a C–H bond). The longest series of linked carbon atoms in a molecule is known as its carbon skeleton or carbon backbone. The number of carbon atoms may be considered as the size of the alkane.
One group of the higher alkanes are waxes, solids at standard ambient temperature and pressure (SATP), for which the number of carbon atoms in the carbon backbone is greater than about 17.
With their repeated –CH2 units, the alkanes constitute a homologous series of organic compounds in which the members differ in molecular mass by multiples of 14.03 u (the total mass of each such methylene-bridge unit, which comprises a single carbon atom of mass 12.01 u and two hydrogen atoms of mass ~1.01 u each).
Methane is produced by methanogenic bacteria and some long-chain alkanes function as pheromones in certain animal species or as protective waxes in plants and fungi. Nevertheless, most alkanes do not have much biological activity. They can be viewed as molecular trees upon which can be hung the more active/reactive functional groups of biological molecules.
The alkanes have two main commercial sources: petroleum (crude oil) and natural gas.
An alkyl group is an alkane-based molecular fragment that bears one open valence for bonding. They are generally abbreviated with the symbol for any organyl group, R, although Alk is sometimes used to specifically symbolize an alkyl group (as opposed to an alkenyl group or aryl group).
^Cite error: The named reference GoldBook alkanes was invoked but never defined (see the help page).
an alkane, or paraffin (a historical trivial name that also has other meanings), is an acyclic saturated hydrocarbon. In other words, an alkane consists...
Higher alkanes are alkanes having nine or more carbon atoms. Nonane is the lightest alkane to have a flash point above 25 °C, and is not classified as...
Perfluoroalkoxy alkanes (PFA) are fluoropolymers. They are copolymers of tetrafluoroethylene (C2F4) and perfluoroethers (C2F3ORf, where Rf is a perfluorinated...
Alkane metathesis is a class of chemical reaction in which an alkane is rearranged to give a longer or shorter alkane product. It is similar to olefin...
aromatic. Aliphatic compounds can be saturated, joined by single bonds (alkanes), or unsaturated, with double bonds (alkenes) or triple bonds (alkynes)...
example, the simplest alkane is CH4 methane, and the nine-carbon alkane CH3(CH2)7CH3 is named nonane. The names of the first four alkanes were derived from...
(C3H8) - an alkane having three carbon atoms in the main chain. The naming of polycyclic alkanes such as bicyclic alkanes and spiro alkanes is more complex...
saturated with hydrogen. The formula for acyclic saturated hydrocarbons (i.e., alkanes) is CnH2n+2.: 623 The most general form of saturated hydrocarbons, (whether...
(Prelog) interactions. Alkane conformers arise from rotation around sp3 hybridised carbon–carbon sigma bonds. The smallest alkane with such a chemical bond...
lipophilic, malleable solids near ambient temperatures. They include higher alkanes and lipids, typically with melting points above about 40 °C (104 °F), melting...
a >1 natural number (which is two hydrogens less than the corresponding alkane). When n is four or more, isomers are possible, distinguished by the position...
recognized. For hydrocarbons: alkene (unsaturated) vs alkane (saturated) alkyne (unsaturated) vs alkane (saturated) arene (unsaturated) vs cycloalkane (saturated)...
15-tetramethylhexadecane, a diterpenoid alkane Icosane, an alkane hydrocarbon Phytane, a diterpenoid alkane This set index page lists chemical structure...
exact mass: 422.4852 u) may refer to: Squalane, branched alkane Triacontane, linear alkane This set index page lists chemical structure articles associated...
C40H82 may refer to: Lycopane, an alkane isoprenoid Tetracontane, an alkane 15,19,23-trimethylheptatriacontane, an alkane pheromone This set index page lists...
The haloalkanes (also known as halogenoalkanes or alkyl halides) are alkanes containing one or more halogen substituents. They are a subset of the general...
very highly refined mineral oil used in cosmetics and for medical purposes Alkane, a saturated hydrocarbon Kerosene, a fuel that is also known as paraffin...
bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The abundance of methane on Earth...
Hexane (/ˈhɛkseɪn/) or n-hexane is an organic compound, a straight-chain alkane with six carbon atoms and the molecular formula C6H14. Hexane is a colorless...
acidic with a pKa near 17. Note, however, this is much more acidic than an alkane or ether hydrogen, which has pKa near 50 approximately, and is even more...
known as dihexyl, bihexyl, adakane 12, or duodecane) is an oily liquid n-alkane hydrocarbon with the chemical formula C12H26 (which has 355 isomers). It...
Tetradecane is an alkane hydrocarbon with the chemical formula CH3(CH2)12CH3. Tetradecane has 1858 structural isomers. Higher alkanes List of isomers of...
Decane is an alkane hydrocarbon with the chemical formula C10H22. Although 75 structural isomers are possible for decane, the term usually refers to the...
Octadecane is an alkane hydrocarbon with the chemical formula CH3(CH2)16CH3. Octadecane is distinguished by being the alkane with the lowest carbon number...
hydroxyl (−OH) and amino (−NH2, −NHR, and −NR2) functional groups on an alkane backbone. Most alkanolamines are colorless. Alkanolamines Methanolamine...
can be the length of a carbon chain, for example in the straight-chained alkanes (paraffins), or it could be the number of monomers in a homopolymer such...
Octane is a hydrocarbon and an alkane with the chemical formula C8H18, and the condensed structural formula CH3(CH2)6CH3. Octane has many structural isomers...
rendering these bond centers so electron deficient that they enable saturated alkanes to participate in electrophilic reactions. The discovery of hypercoordinated...
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