Which shape

[annikaying]

How do you determine if the shape formed will be polar or non polar? For example if a molecule can be either cis or trans(CCl2H2) how do you tell if you are asked to determine if the molecule is polar or non polar?

[Rida Ismail 2E]

it depends on the atoms but in the case of C2H2Cl2 that can be cis or trans. Cis means that the Cl and H are on the same sides. This would be polar because there is a heavy pull on one side and not such a strong pull on the other side. in the trans molecule the Cl and H are distributed opposite from each other so the strong pull of Cl is countered by the other Cl and the H is countered by the other H

[Izzie Capra 2E]

All the atoms surrounding the central atom must be the same in order for the molecule to be non-polar. Since there is Cl and H, that means this molecule will be non-polar because of the electronegativity differences, and the dipoles will not cancel out. The molecule can be either cis or trans, but it will still be non polar regardless in this situation.

[Jenna Ortiguerra 4G]

Nonpolar molecules have zero dipole moment while polar molecules have a nonzero dipole moment. CCl2H2 is polar because the difference in electronegativity between Cl and H are different which creates a difference in dipole moment between the central atom, making it nonzero.

[Mitchell Koss 4G]

It is helpful to watch a YouTube video explaining the difference as many can be determined without looking at Lewis diagram

[April Pazos 3D]

If the dipoles in the molecule do not cancel out, then the molecule will be polar.

[Anthony Hatashita 4H]

Dipoles have to cancel out or it will be polar. I think it helps to look for symmetry in molecules and atoms within molecules to find if something is polar.