Benzene is a planar 6 membered cyclic ring, with each atom in the ring being a carbon atom (Homo-aromatic). Each carbon atom is sp^2 hybridised being bonded to two other carbon atoms and one hydrogen atom. There is a bond angle of 120 degrees around each carbon atom and a carbon-carbon bond length of 140 pm (1.40 Angstroms). Carbon-hydrogen bond length is 109 pm (1.09 Angstroms) Benzene is a delocalised pi-system formed via the overlap of carbon's py orbitals forming a ring of electron density above and below the plane of the benzene ring. Six electrons are donated to the delocalised pi-system, one from each py orbital.