| Number of Carbon atoms | Prefix | Alkyl / Group |
|---|---|---|
| 1 | meth- | methyl |
| 2 | eth- | ethyl |
| 3 | prop- | propyl |
| 4 | but- | butyl |
| 5 | pent- | pentyl |
| 6 | hex- | hexyl |
| 7 | hept- | heptyl |
| 8 | oct- | octyl |
| 9 | non- | nonyl |
| 10 | dec- | decyl |
Hydrocarbon chains can form ring structures that are called alicyclic hydrocarbons. These can be saturated or unsaturated. They are named by adding the prefix, 'cyclo-', eg cyclopentane.
Compounds which contain one or more benzene rings (C6H6) are called aromatic hydrocarbons: