Classes of compound
2. Suffix
The suffix identifies the principal functional group the molecule contains
| Classes of organic compounds | Suffix |
| Alkanes | -ane |
| Alkenes | -ene |
| Alcohols | -ol |
| Aldehydes | -al |
| Ketones | -one |
| Carboxylic acids | -oic acid |
| Esters | -oate |
| Amines | -amine |
| Amides | -amide |