You can determine the number of electron pairs using dot cross diagrams.
Firstly, work out how many electrons there are around the central atom:
- Determine the number of electron in the outer shell of the central atom
- Add one electron for each bond being formed
- Allow for any ion charge on the molecule
The work out the bonding and lone pairs:
- Divide by 2 to find the total number of electron pairs
- Determine how many bonding pairs there are by how many other atoms are bonded to the central atom
- Any pairs that aren't bonding pairs are called lone pairs
Finally, arrange the electron pairs to minimise repulsion
Comments
No comments have yet been made