Give the molecular formula of benzene. Give the Kekule structure of benzene and then explain why this structure is not correct. Give the accepted structure for benzene (5 marks).
Molecular formula: C6H6The Kekule structure (draw on whiteboard in session) - has the hexagonal shape of the ring, with a carbon=carbon double bond on every other carbon-carbon link. This has been proven to be incorrect - the bond lengths in a benzene ring have been measured and the lengths of all six bonds are the same. The lengths measured put the bonds as between the length of carbon=carbon double bonds (shorter) and carbon-carbon single bonds (longer) leading to the currently accepted structure of benzene with the ring of delocalised electrons present (draw in session).
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