How do you determine if a molecule non polar?
A molecule is non-polar iff the
There are 2 different types we're talking about.
Intramolecular forces: The net electronegativity, which is calculated by subtracting the element with the lower electronegativity from the element with the higher electronegativity. If that difference is below
VSEPR shape/atom symmetry: After determining your covalent bond (because only molecules with a
In summary, if the difference in electronegativity is below
- Methane (
#"CH"_4#) has a net #chi#of 0.4 - it has non-polar covalent bonds. It's also symmetrical thus it is a non-polar molecule (in general).
- Boron trichloride (
#"BCl"_3#) has a net #chi#of 1 - it has polar covalent bonds. However, it is symmetrical, thus it is non-polar in general but has polar covalent bonds.