AXE notation [ENDORSED]

[Nora 1F]

Can somebody explain how AXE notation is used? Will knowing AXE notations be sufficient for naming molecular shapes?

[Nancy Dinh 2J]

A - Means atom. You will always have this.
X - Number of bonded pairs to the central atom. You will have at least on X in order for there to be a molecule.
E - Number of lone pairs on the central atom. It is possible to not have any lone pairs, so you will simply omit E if needed.

The number of bonded pairs and lone pairs are written as a subscript to their respective notation.
For example, an atom with 3 bonded pairs and 1 lone pair will have a notation of AX3E

[Brigita1D]

Knowing the AXE notations can help identify molecular shapes of structures because molecules with the same formulas usually have the same shapes.

[Sohini Halder 1G]

Add up the subscripts on AXE and you will know how many regions of electron density there are. The subscript below X tells you how many atoms are attached to the central atom. When naming the molecule's shape, you need to know both in order to discern how the lone pairs, if there are any, affect the shape.