Alevel chemistry: Aromatic compounds

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  • Created by: Rachaelg
  • Created on: 15-07-20 15:30

Aromatic compounds and reactions of Benzene 

Benzene is a hydrocarbon compound with a molecular formula of C6H6

The original model for the structure of benzene - Kekules' model stated that benzene was formed of 3 alternating double bonds in a ring of the six carbon atoms. The model was proven wrong due to the following evidence:

  • benzene doesn't undergo electrophilic addition- suggesting there aren't any double bonds
  • bond lengths in benzene are all the same - shorter than a single bond and longer than a double bond
  • The enthalpy change of hydrogenation was less than expected 

The new delocalised model proposes that benzene is formed of six carbon atoms joined with single sigma bonds and the p orbital electrons are spread above and below the plain in a delocalised pi system.

Naming compounds with benzene rings:

When naming compounds with only one constituent group a prefix is used such as ethyl or chloro and the word benzene is

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