Chad provides a comprehensive lesson on how to determine if a molecule is polar or nonpolar based upon its individual bond dipoles and its molecular geometry. The lesson begins with a review of electronegativity and relative bond polarity. It is then demonstrated that if the bond dipoles in a molecule sum to zero (i.e. "cancel") then a molecule is termed nonpolar, and a good example of this is CO2. It is then shown that if the central atom does not have lone pairs of electrons and if the atoms surrounding it are all the same then it will be nonpolar (as in CO2, BCl3, and CF4). It is also shown that if the central atom has lone pairs of electrons then it will USUALLY be polar (as in SO2, NF3, and H2O), but there are two MAJOR exceptions. If all the atoms surrounding the central atom are once again identical but the molecular geometry is either square planar or linear (linear with 2 bonding and 3 nonbonding electron domains) then the molecule will still be nonpolar (XeF4 and XeF2 are examples of these respectively).

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00:00 Lesson Introduction
00:47 Review of Electronegativity
02:33 Bond Polarity vs Molecular Polarity
08:24 CH2Cl2 is Polar
11:25 CO2, BCl3, & CF4 are Nonpolar
14:23 SO2, NF3, and H2O are Polar
17:48 XeF4 & XeF2 are Nonpolar

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