1. Lewis Dot Structures

2. Lewis Dot Structures Also known as lewis dot diagrams
Lewis dot diagrams are a way to show the number of valence electrons in an atom
They are represented by the elements symbol surrounded by dots (one for each valence electron the atom possesses)
Elements in the same group on the periodic table will have the same Lewis Dot Structure because they have the same number of valence electrons

3. Examples of Lewis Dot Structures
Li N Ne

4. Writing Lewis Dot Structures
When you write a lewis dot structure you follow three steps:
Write the symbol of the element (with room on all sides)
Determine the number of valence electrons (using the periodic table)
Beginning at the right hand side of the symbol draw the dots moving clockwise around the symbol one on each side at a time NO MORE than TWO dots on each side of the symbol.

5. Writing Lewis Dot Structures- Example
Writing the Lewis Dot Structure for Nitrogen:
Write the symbol N
2. Determine the number of valence electrons-
Nitrogen has 5 valence electrons because it is a group 5 element.
3. Begin Drawing dots:
N N N N N

6. Using Lewis Dot Structures to Represent Ions
Lewis Dot Structures can be used to represent ions (elements with a charge)
Sodium Atom Sodium Ion
Na ( - e-) Na +
11 p p+
11 e e-

7. Using Lewis Dot Structures to Represent Ions
Sodium Atom Sodium IonF ( + e-) F -
11 p p+
11 e e-