Explain the structure and characteristics of benzene
Initally, benzene was thought to have the kekule structure. This was thought to be an interconversion of two different discrete strucutres of a 6 carbon ring with single and double bonds. However there were some serious problems with this strucutre:
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Benzene is very unreactive. This is very unusual considering the fact that it was assumed to have three double bonds, and double bonds are very reactive and especially undergo addition reactions.
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Benzene is a planar molecule, and using X-ray diffraction technology it was seen that the bond lengths were all the same and were in between the length of a single and double bond,
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Benzene is much more stable than the kekule structure predicts. The complete hydrogenation of the molecule has a difference in actual values and values with the theoretical kekule structure by 150J/mol. this is due to the resosnance stabilisation energy of the benzene ring
It was found that benzne exists as a conjugated ring. This means that it is not an interconversion of structures, but a conversion of both of them to crease a delocalised cloud which lies above and below the plane of the benzene ring.
