Aromaticity in chemistry refers to the special stability of certain cyclic compounds that follow Hückel's rule. According to Hückel's rule, a molecule is aromatic if it contains a planar ring structure with a total number of π-electrons that is a multiple of 4 + 2 (i.e., 6, 10, 14, etc.).
- Option (a) Cyclohexene: This is not aromatic because it has a double bond but does not fulfill the required π-electron count or conjugation to be considered aromatic.
- Option (b) Cyclopropene: This is also not aromatic because it does not follow Hückel's rule and is not planar.
- Option (c) Benzene: Benzene is a classic example of an aromatic compound as it has a conjugated system of double bonds and follows Hückel's rule, having 6 π-electrons.
- Option (d) Non-aromatic: This option is incorrect because it doesn’t refer to a specific molecule.
Thus, benzene (option c) is the aromatic compound.