Dipole Question

[Dentbound1234]

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Can a molecule have a dipole moment and still be non-polar?
All the research I did showed molecules that have dipole moment are polar.
Wondering if there are any special cases?

^..^

 

[embrojam]

Molecules can have bond dipoles but overall be nonpolar if the dipoles cancel out.

Classic example is CO2. O=C=O
Oxygen is more E.N. compared to C, so there is a bonding dipole. However, the molecule is linear, and the two dipoles from the two bonds cancel each other out, as they are pointed in exactly opposite directions. Therefore, CO2 is nonpolar because of the symmetry

 

[Dentbound1234]

Thank you.

^..^

 

[plusalpha]

CF4 is also another great example. The individual C-F bonds are polar due to the highly electronegative F atom, but as a WHOLE molecule, CF4 has a perfect tetrahedral molecular geometry without any lone pairs, so the dipoles cancel out, making CF4 a non-polar molecule