regions of electron density

[Sondia Luong 1C]

When using VSEPR theory to predict the shape of a molecule, are the number of regions of electron densities based on lone pairs and bonds? For bonds, would a double bond account for 2 regions of electron density? If it does, how would that affect the shape of the molecule? Thanks!

[Akshata Kapadne 2K]

Yes, the number of regions of electron density is based on both lone pairs and bonds. I believe a double bond or triple bond is just one region of electron density, though.

[kateraelDis1L]

this is correct^^ single, double, and triple bonds are considered one region of electron density. ;)

[Samudrala_Vaishnavi 3A]

I wouldn't overthink it too much but I would think that the areas of electron density are where there are clusters of electrons (especially lone pairs). Double and Triple bonds are just another cluster of electrons so they are only considered one region of electron density which is similar to any other surrounding atoms having lone pairs (also considered their own region of electron density). I think that with these concepts, the more the practice problems, the easier to identify and understand which areas are regions of electron density.

[AnnaNovoselov1G]

Another thing to remember is that lone pair electrons contribute to the shape of a molecule, but they are not considered when determining the name of the molecular shape. The lone pairs also have greater repulsion than the bonds.

So while both bonds and lone pairs are both considered regions of electron density, they have different properties and consequences.

[derickngo3d]

Regardless of bond order, all covalent bond are one region of electron density. Lone pairs also count as regions of electron density.

[Juwon Lim 2A]

Regions of electron density is determined by counting bonds and line pairs. Double bonds and Triple bonds count as 1 region of electron density, since they occupy one region.

[Carly_Lipschitz_3H]

The number of regions of electron densities are based on lone pairs and bonds. But, a double bond doesn't account for two regions of electron density. Single, double, and triple bonds all account for one region of electron density. Lone pairs also count as one region of electron density.