Hydrocarbons

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Revision as of 00:31, 7 November 2007 by imported>David E. Volk (volitile --> volatile)
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Hydrocarbons are a class of molecules that contain only carbon and hydrogen atoms. They are very volatile (have a high vapor pressure), flammable, and generally make very good fuels. Gasoline contains a mixture of hydrocarbons. Unsaturated hydrocarbons, which contain one or more double bonds, are useful chemicals for many reactions.

Linear saturated hydrocarbons

The simplest hydrocarbons are linear molecules in which each carbon atoms is bonded to two other carbons atoms, in a linear fashion, except for the carbon atoms at the ends, which are only bonded to one other carbon atom. Saturated hydrocarbon names generally end with the suffix "ane" which distinguishes them from unsaturated hydrocarbons, which end with the suffix "ene".

Hydrocarbon nameChemical Formula
MethaneCH4
EthaneCH3-CH3
PropaneCH3-CH2-CH3
ButaneCH3-CH2-CH2-CH3
PentaneCH3-(CH2)3-CH2-CH3
HextaneCH3-(CH2)4-CH2-CH3
HeptaneCH3-(CH2)5-CH2-CH3
OctaneCH3-(CH2)6-CH2-CH3
NonaneCH3-(CH2)7-CH2-CH3
DecaneCH3-(CH2)8-CH2-CH3
UndecaneCH3-(CH2)9-CH2-CH3
DodecaneCH3-(CH2)10-CH2-CH3

Linear unsaturated hydrogcarbons

Unsaturated hydrocarbons are useful precursor molecules for many reactions. Because they contain one or more double bonds, a large variety of chemical transformations are possible. Unsaturated hydrocarbons generally end with the "ene" suffix, although common names are sometimes used instead of the IUPAC designation. In addition, a numerical prefix is used to indicate the position of the double bond(s).

Hydrocarbon nameChemical Formula
EtheneCH2-CH2
PropeneCH2-CH-CH3
1-ButeneCH2-CH-CH2-CH3
2-ButeneCH3-CH-CH-CH3
1-PentaneCH2-CH-(CH)2-CH2-CH3


cyclic saturated hydrocarbons

cyclic unsaturated hydrocarbons

aromatic hydrocarbons