why is dipole moment of chloro methane greater than fluoro methane

Dear yash khanna,

CH₃F has less dipole moment than CH₃Cl because of short C-F bond length.(dipole moment=qd)
CH3F has more dipole moment since F is more electronegative as compared to chlorine and attracts the shared pair of electrons between CH3 and itself more towards itself.
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Godfrey Classic Prince
IIT-Madras
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due to small size of Flourine the shared pair of electrons are attracted towards flourine and hence bond lenght decreases whereas in chlorine it is not so happened and hence dipole moment of flouromethane is less than that of chloromethane.

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