Illustrated Glossary of Organic Chemistry

Functional group: A group of atoms whose bonding is the same from molecule to molecule. A functional group has similar behavior regardless of the molecule that contains it, so molecules with identical functional groups tend to have similar chemical and physical properties. In addition, functional groups with similar structures tend to impart similar chemical and physical properties to the molecules which contain them.

Common Functional Groups
  - means 'attached atom does not matter'      * means carbon or hydrogen here
Alkene

Alkyne

Benzene ring

Alkyl halide
X = F, Cl, Br, or I
Also called haloalkane

Alcohol

Phenol

Ether

Thiol
Also called mercaptan

Sulfide
Also called thioether

Disulfide

Amine

Ketone

Aldehyde

Carboxylic acid
Often abbreviated RCOOH

Ester
Often abbreviated RCOOR or RCO2R

Amide

Acid chloride
Also called acyl chloride

Acid anhydride
Also called anhydride

Carboxylate
Also called carboxylate ion

Imine
Also called Schiff base

Nitrile


Nitro