6.1.6 Aromatic Compounds

State the formula of Benzene?

C6H6

which 2 models represent benzene?

• the kekule model

• the delocalised model

what does a benzene molecule consist of?

• a cyclic structure with 6 carbon atoms joined together in a ring

what type of compound is benzene classified as?

an aromatic compound/arene

what did kekule suggest benzene was made up of?

• that benzene was made up of a planar ring of carbon atoms with alternating double and single bonds between them

why is kekule’s model incorrect?

• if benzene consisted of alternating double and single bonds it would react like an alkene

• by electrophilic addition

• but benzene does not carry out electrophilic addition

• also doesn’t give positive bromine water test

• therefore benzene does not contain double bonds

• x ray diffraction tells us that single carbon bonds are longer than double carbon bonds

• however in benzene both have same length

• structure of benzene is more stable than kekules proposed model