Question

All three of the phosphorus-fluorine single bonds in pf3 are polar. in which direction should the polarity arrows point?

Answer 1

One of the causes of polarity is the unequal forces of the dipole forces due to differences in electronegativity. The more electronegative molecule tend to attract electrons, hence the polarity arrows point towards it. The electronegativity of Phosphorus and Fluorine is 2.19 and 3.98, respectively. Thus, it points outward towards the fluorine atoms.