Why is PBr5 considered non polar when its difference in electronegativity is 0.7, which would make it polar covalent? Is it then polar covalent or how do we determine how it is non-polar?

Question

Why is PBr5 considered non polar when its difference in electronegativity is 0.7, which would make it polar covalent?   Is it then polar covalent or how do we determine how it is non-polar?

DrBob222 · Answer

The 50-50 break even point for polar/non-polar is about 1.7. Anything less than that is considered non-polar. That number is not fixed; I have seen some profs use as low as 1.5 and as high s 1.9. So a difference of 0.7 I would call polar covalent. Certainly not very polar. Probably 15% polar or less.