Symmetrical Molecules

(Polar molecules, Non-polar molecules, etc.)

Moderators: Chem_Mod, Chem_Admin

Tara Foroohar 3K
Posts: 20
Joined: Fri Sep 29, 2017 7:06 am

Symmetrical Molecules

Postby Tara Foroohar 3K » Sun Nov 26, 2017 8:57 pm

Hi guys! Will there ever be a scenario in which the molecule is symmetrical but polar? Or are all symmetrical molecules nonpolar

Alex Kashou
Posts: 38
Joined: Fri Sep 29, 2017 7:07 am

Re: Symmetrical Molecules

Postby Alex Kashou » Sun Nov 26, 2017 9:00 pm

Yes; for example, CH2Cl is symmetrical about the C but the Cl is more electronegative resulting in a greater pull towards that location of the symmetrical shape. Therefore, the molecule is polar because there is distinct dipole moment on one side of the molecule.

Aijun Zhang 1D
Posts: 53
Joined: Tue Oct 10, 2017 7:13 am

Re: Symmetrical Molecules

Postby Aijun Zhang 1D » Sun Nov 26, 2017 9:13 pm

For symmetrical molecules, the polar effect can be canceled. So they are non polar molecules.
Though some molecules will have polar bonds, but if the whole molecule is symmetrical, the polar effect can be canceled out. The polar molecule such as water has an uneven distribution of electron density.

Nicole Nikolov 1K
Posts: 50
Joined: Fri Sep 29, 2017 7:05 am

Re: Symmetrical Molecules

Postby Nicole Nikolov 1K » Sun Nov 26, 2017 11:48 pm

If a molecule is completely symmetrical, then it will be nonpolar. However, when it comes to 3D molecules and more complex molecules it can get a bit more tricky. Even if these molecules look symmetrical at first glance based on their shape, you have to make sure that all of the dipole moments between each of the molecules also cancel.


Return to “Determining Molecular Shape (VSEPR)”