Benzene

Benzene is a 6 carbon, 6 hydrocarbon ring compound in organic chemistry with formula C₆H₆. 

Benzene's structure consists of a regular hexagon of 6 bonded carbon atoms, each with a hydrogen bonded outside of the ring. The carbons are bonded to each other by a normal sigma bond but also by delocalised electrons above and below the ring. Because these electorns are delocalised the bond lengths in benzene are equal. This gives benzene unsual chemical properties as well as greater stability over its isomers, e.g. cyclohexene.

Benzene is a carcinogen.