Which of the following has been arranged in the order of decreasing dipole moments?
Greater the value of electronegativity, higher will be the dipole moment. So, CHF3 is expected to have greater dipole moment. But, due to extreme smaller size of fluorine, the dipole moment of CHCl3 outerweighs that of CHF3. So the order of dipole moment is CH3Cl>CH3F>CH3Br>CH3I