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  The electrons in this pi (π) bond system do not belong to any particular carbon atom. Each electron is free to move throughout the entire pi (π) system. It is for this reason the electrons are said to be delocalized. In fact, this delocalization gives extra stability to benzene Delocalized in fact, this delocalization Therefore, benzene is represented by putting a circle in a regular hexagonal shape. The structure of benzene with the ring of pi (π) electron system is very stable that even it retain its structure during substitution reactions. SHAPES AND BOND ANGLES IN MOLECULES BY USING VSEPR THEORY:             In covalent molecules electron pains forming the bonds are distributed in space around the central atom along definite directions. The shared electron pairs as well as the lone pair of electrons are responsible for the shape of molecules. The basic rules of valence s...