(ii) Using the benzene ring and E+ as an electrophile, illustrate how electrophilic substitution occurs in benzene (5 marks)?

In the first step of electrophilic substitution in benzene, the electrophile E+ attacks the benzene ring. This results in the formation of a sigma complex, where the electrophile is temporarily bonded to one of the carbon atoms in the benzene ring.

Next, the pi electrons in the benzene ring shift towards the carbon atom that is bonded to the electrophile, breaking the bond between that carbon atom and one of its hydrogen atoms. This results in the formation of a carbocation intermediate.

In the final step, a proton from the solvent or another molecule acts as a base and removes the hydrogen atom from the carbon atom that is bonded to the electrophile. This results in the regeneration of the aromaticity of the benzene ring, with the electrophile now bonded to one of the carbon atoms in the ring.

Overall, the electrophilic substitution reaction in benzene involves the attack of an electrophile on the benzene ring, the formation of a sigma complex and a carbocation intermediate, and the removal of a hydrogen atom to regenerate the aromaticity of the benzene ring.