polar vs non-polar molecules

[Sofia Cerpa 2E]

hello, can someone please explain the difference between polar and non-polar, and how to identify when a molecule is one or the other? thank you, your help is very much appreciated! :)

[Emily Ngo 1E]

Hi Sofia,
A polar molecule must have polar bonds with dipoles that do not cancel. A nonpolar molecule must have zero electric dipole moment which is possible if it contains nonpolar bonds OR polar bonds with dipoles that cancel. For example, CCl4 would be nonpolar because the dipoles all cancel and the electrical charge is evenly distributed. Hope this helped!

[Ellie Fox 2K]

Polar bonds form when two bonded atoms have differing electronegativity and therefore electrons are shared unequally. On the other hand, non-polar bonds form when two bonded atoms have very similar electronegativity and therefore electrons are shared equally.

[Joshua Lee 3C]

Polar molecules exist when polar bonds and their resulting dipoles do not cancel out in a molecule. Nonpolar is the opposite, in which all the dipoles in a molecule cancel out. You can check this by drawing the lewis structure of the molecule and using VSPER model to envision the molecule in three dimensions to see if the dipoles cancel each other out. Polar molecules have permanent dipoles and are thus able to take part in dipole-dipole, dipole-ion, and dipole-induced dipole forces. Nonpolar molecules do not have permanent dipoles.