Influences on Polarity

[Sydney Kim 3L]

What factors influence polarity?

[Arya_Naeim_1H]

There has to be dipole moments in a molecule where the uneven sharing of electorns in a molecule occur. Additionally, the net dipoles cannot cancel out. In CF4, even though F is more electrongeative leading to the uneven sharing of electrons the tetrahedral shape of CF4 leads to the dipole moments cancelling out and CF4 is nonpolar. However in CHF3, the dipole moments are not all equal on ever side of the molecule and therefore CHF3 is a polar molecule.

[Amanda 3A]

The 2 factors in determining polarity is the shape of the molecule and the polarity of its bonds, so you look at the positive and negative charges of the atoms and when looking at the shape you look to see the direction of the bond dipoles as the direction is based on shape.