Molecular geometry
Predict firstThe central carbon of CO₂ has two double bonds; how many bonding electron domains does it have?
Keep electron domains, molecular shape, and orbital descriptions apart.
Prerequisites: Valence electrons take part in bonding; a lone pair does not form a bond between two atoms.Count directions, not lines
Predict firstThe central carbon of CO₂ has two double bonds; how many bonding electron domains does it have?
In VSEPR every multiple bond counts as one electron domain. Two domains point in opposite directions, so CO₂ is linear. The electron domain is an approximate concept used to predict the spatial arrangement.
How to observe
- Compare the molecular shape with the spatial arrangement of the electron domains
- Overlay the space-filling outline to see how abstract a ball-and-stick model is
- Look at the side-on overlap of the p orbitals in ethene
Model notes
Teaching geometry for molecules; the bond angles are ideal or representative values, and bond lengths and atomic display radii are scaled. The translucent orbital lobes show orientation, not an electron-density isosurface. Hybridization is a mathematical combination of orbitals used to describe bonding, not a mechanical motion that the atoms perform first.