1. Valence Electrons and Lewis Dot Structures

2. 118 Known Elements 1 ve - 2 ve - 3 ve - 4 ve - 5 ve - 6 ve - 7 ve - 8 ve - ve - = valence electrons IGNORE THESE YOU WILL USE THEM IN CHEM NOT BIO

3. Valence Electrons Practice 1. How many valence electrons are in Carbon? 2. How many valence electrons are in Argon? 3. How many valence electrons are in Beryllium 4. How many valence electrons are in Lithium 5. How many valence electrons are in Francinium? 6. How many valence electrons in Calcium? 7. How many valence electrons in Kyrpton? 8. How many valence electrons in Arsenic? 9. How many valence electrons in Magnesium? 10. How many electrons in Oxygen?

4. Lewis Structures All you have to do for a Lewis Structure is draw Dots around an Element’s Symbol But How Many????

5. What you are about to learn 1. How many Electrons are found in any Element’s Valence Shell 2. How to draw a Lewis Structure

6. So… The amount of dots you draw for a Lewis Structure (LS for short) is equal to the # of Valence Electrons in an Atom

7. Valence Electrons The # of Valence e- an atom has is dictated by the Group the Element is in Groups are the Vertical Columns on the Periodic Table!!! It’s So Simple!!!!

8. Practice: The First Two Are Tricky so pay attention

9. Practice: All Elements in the first group have only 1 Valence e-

10. Practice: All Elements in the first group would have a LS like this: H

11. Practice: All Elements in the second group have only 2 Valence e-

12. Practice: But what about Helium!!! It only has 2 e- so it can only have 2 e- in its Valence Shell

13. Practice: All Elements in the second group would have a LS like this He

14. So… Group 3 3 Valence e- Structure like this: B

15. Lewis Dot Structure Order

16. Now you should know 1. How many Electrons are found in any Element’s Valence Shell 2. How to draw a Lewis Structure

17. Element Group Number (PT)# of Valance ElectronsLewis Dot Structure Calcium Carbon Hydrogen Helium Oxygen Fluorine Neon Sodium Aluminum 2 2 Ca 4 4 1 1 8 2 6 6 7 7 8 8 1 1 3 3 C H He O F N Na Al