Dipole moment halomethanes

Dipole moment (n ), 38 halomethanes, 335 polar covalent bonds and, 38-39 table of, 39... 

Carbon-halogen bonds are polar, and halomethanes have dipole moments. 

Halomethane Bond length (pm) (kJ/mol) (kcal/mol) Dipole moment (D)... 

Fluorine, chlorine, and bromine are all more electronegative than carbon (Table 1.5) as a result, C—bonds with these atoms are polarized with a partial negative charge on halogen and a partial positive charge on carbon. Table 8.1 shows that each of the halomethanes has a substantial dipole moment. The electrostatic potential map of fluo-romethane shows the large charge separation in this compound caused by the dipole. 

The magnitude of a dipole moment depends on the size of the partial charges, the distance between them, and the polarizability of the three pairs of imshared electrons on each halogen. For the halomethanes, the dipole moment increases as the electronegativity of the halogen and the bond length increase. These two trends run... 

Halomethane Electronegativity of Halogen Caitran-Halogen Bond Length (pm) Dipole Moment (debyes, D)... 

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