Define aromatic compounds and provide an example.

Aromatic compounds are organic compounds that contain a ring of atoms with alternating double bonds.

Aromatic compounds are a class of organic compounds that contain a ring of atoms with alternating double bonds. These compounds are characterized by their strong and pleasant odours, which is where the name "aromatic" comes from. The most common aromatic compound is benzene, which has a six-carbon ring with alternating double bonds. Benzene is a highly flammable liquid that is used in the production of many chemicals, including plastics, rubber, and dyes. It is also a known carcinogen and exposure to it can cause cancer. Other examples of aromatic compounds include toluene, naphthalene, and phenol. Toluene is used as a solvent in many industrial processes, while naphthalene is used in mothballs and as a fuel additive. Phenol is used in the production of plastics, resins, and pharmaceuticals. Aromatic compounds are important in many areas of chemistry, including organic synthesis, biochemistry, and materials science. They are also important in the study of organic reactions and mechanisms.