- Nineteenth-century chemists classified hydrocarbons as either aliphatic or aromatic on the basis of their sources and properties.
- Aliphatic (from Greek aleiphar, “fat”) hydrocarbons derive from the chemical breakdown of fats or oils. They are divided into alkanes, alkenes, and alkynes.
- Alkanes have only single bonds, alkenes contain a carbon-carbon double bond, and alkynes contain a carbon-carbon triple bond.
- Aromatic hydrocarbons make up a group of related substances obtained by chemical breakdown of certain pleasant-smelling plant extracts. They are classified as either arenes, which contain a benzene ring as a structural unit, or as nonbenzenoid aromatic hydrocarbons, which possess special stability but lack a benzene ring.
hydrocarbon Article