Explain the orbital concept of resonance and resonance effect.

Resonance is of representing a structure in a way of describing the delocalised electrons because that compound cannot be expressed by any one structure.

Resonance structure of benzene will explain this effect in a better way

: Benzene can be represented by the resonance hybrid

This indicates that all C—C bonds are equivalent and intermediate between a single and a double bond.

The given diagram shows the delocalisation of electrons in the (equivalent) orbitals, since the electrons are delocalised and do not exist in only one single form it is best represented as its hybrid form with a ring in the centre showing the delocalisation