Question

Explain why ch3cl has a higher dipole moment than than ch3br

Answer 1

As the size of fluorine is less compared to chlorine the bond pair electrons of carbon-fluorine bond will get repelled by the lone pair electrons of fluorine. So the dipole moment will decrease.While this will not happen in chloromethane.CH3Cl has larger dipole moment than CH3F because dipole moment is based on the product of distance and charge, and not just charge alone…….Fluorine is more electronegative than chlorine, but, the carbon-fluorine bond is also much shorter than the carbon-chlorine bond: 139 pm vs 178 pm. Thats why the dipole moment of chloromethane is higher than the dipole moment of fluoromethane.
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