12/1 Lewis Diagrams.
Lewis Diagrams 
AKA electron dot structures
When Atoms Combine 
Only valence electrons are involved
Learning Lewis diagrams is the first step in
understanding chemical reactions
Steps 
1) Write the element symbol
2) Start at 12:00 and move clock
And place the dots for the valence electrons
one at a time around the symbol.
3) Place the dots over 4 sides
4) Dots are not paired until all sides have at
least one dot.
You tube – How to draw Lewis structures. Five easy steps.
Task:
Find valence electrons and draw Lewis Diagrams for the first 20 elements.
H
He
Li
Be
B
C
N
O
F
Ne
Na
Mg
Al
Si
P
S
Cl
Ar
K
Ca