Ionic Lewis Structures
Chemistry: IB Diploma Higher Level, topic 2.3.1
Lewis Diagrams
Lewis diagrams can show electrons being transferred and ions being formed.

Lewis diagrams
- Dots represent electrons from 1 atom and crosses represent electrons from the other atom.
- Square brackets and a charge (e.g. 2+) represent ions.

Sodium + fluorine
- The sodium atom transfers its outer electron to the fluorine atom, creating Na+ and F- ions. Both of these ions have full outer shells.
%202.1.2.2%20-%20Ca%20and%20O%20atoms%20%E2%86%92%20Ca2%2B%20and%20O2-%20ions%20(1)-min,w_800.jpg)
Calcium + oxygen
- The calcium atom transfers its 2 outer electrons to the oxygen atom, creating Ca2+ and O2- ions which both have full outer shells.
Test yourself on Ionic Lewis Structures
What can we show using Lewis diagrams?
Sodium is in group 1 and oxygen is in group 6. In the Lewis diagram for sodium oxide, how many sodium ions would there be?