polar/nonpolar

[204929947]

I'm still a little confused on when a molecule is polar or not. So if the forces cancel out it is polar? The forces have to be facing each other right? (--><-- like that)

[Ellie Tsang 1I]

A polar molecule is a molecule that has a nonzero dipole moment, while a nonpolar molecule is a molecule that has no dipole moment. That means in polar molecules, the forces do not cancel out. Instead, the forces will cancel out for nonpolar molecules.

[Alexis Bravo 1D]

The nonpolar molecules are those in which the forces cancel out and the polar molecules are molecules that have unequal dipole charges that don’t cancel out.

[Bianca Nguyen 1B]

To give examples, CCl4 is a nonpolar molecule because although it has 4 dipole moments all going towards the Cls, the dipole moments cancel out due to the symmetry of the molecule. BUT, if you replace two of the Cl atoms in the molecule with Br atoms, making CBr2Cl2, the new molecule is polar because the dipoles do not cancel since there is no symmetry due to different atoms being attached to the C.