What happens to electrons when a polar covalent bond forms?

1 Answer
Dec 5, 2016

They are unequally shared about the species.


Consider the diagram of #CH_4# and look for a perspective dipole moment:
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In the C-H bonds, the electron are shared unequally between Carbon and Hydrogen. The dipole points toward Carbon because the C-H bond is polar covalent, and this is because Carbon is more electronegative than Hydrogen.

However in #CH_4#, the dipoles created by the C-H bonds cancel each other out, and as you can observe there is no dipole moment.