1. Dot Notation

2. Materials Needed
Periodic Table

3. Identify # of Valence Electrons
Valence electrons determine the chemical characteristics of elements.
The chemical characteristics in each GROUP are similar.
Because- The number of valence electrons in each group are the same.

4. Ignore Transition & Rare Earth Metals
Too complicated with those at the moment.

5. Consider an example of each group.
Consider Electron Configuration:
Hydrogen: 1s1: 1 Valence e-
Beryllium: 2s2: 2 Valence e-
Consider Electron Shells
Boron: 5 total e-, 2 for the first shell, 3 in valence shell …
Carbon 4, nitrogen 5, oxygen 6, fluorine 7, Helium 2 (Full)

6. A Convenient Pattern 1 8 2 3 4 5 6 7

7. Trick to remember: Groups 1 & 2: Their group # = # of valence of e-
Groups 13-18: # of valence electrons = group # - 10

8. Drawing the Dots
The number of dots equals the number of valence electrons.
Steps:
Write the element’s symbol.
Start with a dot to the right.
Moving clockwise, draw a dot on every side of the symbol until all valence e- are represented.

9. Al Consider Aluminum Aluminum has 13 electrons: 2 on inner shell
8 on next shell
3 on valence shell Al

10. Br Consider Bromine Bromine has a Noble Gas Notation: [Ar] 4s2 4p5
Since we know Ar is stable, all the e- represented by its notation are stable.
Add the exponents to determine 7 e- on the valence shell. Br

11. Summarize
Write a 3-5 sentence summary how to determine and draw the valence electron of an atom in Dot Notation.