Question
Explain why the dipole moment of chlorobenzene is lower than that of cyclohexyl chloride?
Solution
The dipole moment of chlorobenzene is less than cyclohexyl chloride as in chloro benzene because C-Cl bond is sp2 hybridised where as in cyclohexyl chloride the C-Cl bond is SP3 Hybridised . Since sp2 has more s character and more electronegative than sp3. Also, In chlorobenzene resonance gives rise to partial double bond charcter to the carbon- halogen bond, making it stronger by reducing the polarity of the carbon -halogen bond. Hence, chlorobenzene is less polar than cyclohexyl chloride.