Nature of C-X bond

The C in the C – X bond is carbon while the halogen is denoted by X. The large electronegativity of the halogen causes the electron cloud to attract more electrons towards itself and thus gain a slight negative charge, while carbon possess a slight positive charge. Since halogens require only one electron to reach the closest inert gas composition, the octet state, only one sigma bond is formed between the carbon and halogen atoms. The C-X bond length of haloarene increases with increasing atomic size from fluorine to astatine, reducing the strength of bond dissociation.