Chemical Bonding: Molecular Geometry

Molecular Geometry Image

If we have a Lewis structure we’re ready to go from 2D to 3D. The 3D shape of a molecule has a lot to do with how the molecule behaves. Think about DNA – the molecular geometry of the double helix is why it can store so much information. A few things to note:

  • You need to have the correct Lewis structure first.
  • You’ll look at the number of chemical bonds and then the number of nonbonding electron pairs. Then it’s just a matter of looking it up in a table (or memorizing the table below).
  • You should be able to visualize the general shapes. Watching a video or working with molecular models (plastic or wood) is helpful. Take time to quickly recognize the shapes you need to know.

Video: Molecular Geometry (Shape of Molecules)

Video: Molecular Geometry: Examples

Table of Molecular Geometries
Molecular Geometry Table (Shapes of Molecules, Bond Angle, and Hybridization)