1. Lewis Dot Symbols/Structures
Covalent Bond: a bond between two non-metal atoms where electrons are shared
Lewis Dot Symbol: a way to represent valence electrons for an atom
The order for drawing a Lewis Dot Symbol:
(think “box”)

2. Lewis Dot Symbols/Structures
NOTE!: to find out how many “dots” an element will have, figure out the number of valence electrons it has
Example: Nitrogen has 5 va e-  should have 5 dots
Oxygen
Neon
Nitrogen
Fluorine
Boron
Hydrogen
Beryllium
Carbon

3. Lewis Dot Symbols/Structures
lone pair – does not bond
unpaired electron – forms a
bond

4. Lewis Dot Symbols/Structures
Octet Rule: atoms tend to form bonds by sharing valence electrons until eight valence electrons surround each atom
EXCEPTIONS! - Hydrogen, Helium, and Boron
Hydrogen – 2 total valence electrons
Helium – 2 total valence electrons
Boron – 6 total valence electrons

5. Lewis Dot Structures Practice
Copy down the following molecular formulas and draw the correct Lewis Dot Structure for each.
1. HCl
2. CH4
3. H2O
4. BH3
5. NF3
6. F2O
7. NH3
8. BF3
9. CF2Cl2
10. C2H6
11. SiO2
12. CH3N
13. C2H4
14. O2
15. CO2
16. N2
17. HCN
18. CH2O2