Lewis Dot Diagrams - Part Two

Some elements can break the Octet Rule by having more than eight electrons. We call this having an expanded octet. It can happen because electrons can be "promoted" into the 3d orbitals to accommodate bonding. There are a couple of "rules" around this:

1. The atom must already have electrons in both the 3s and 3p sub-levels.
2. The atoms must be the central atom (it would be anyway, as this increases its valency)