1. Lewis Dot Structures
It’s all about the dots

2. What do we know? Valence Electrons: What are they?
Why are they important?
How do we find them on the periodic table?
Valence Electrons are the outermost electrons in an atom.

3. What else?       How do we find valence electrons using:
Orbital Diagrams?
Electron Configuration?
1s² 2s² 2p⁶ 3s¹      

4. Why do we use Lewis Dot Structures?
We use them for many reasons:
To show the amount of valence electrons
To provide a diagram to work with
To describe bonding
So what do they look like?
Here’s a Lewis Diagram for Boron:
How would we draw a Lewis Diagram for
(a) Carbon and (b) Nitrogen B C N

5. From Atomic to Lewis
Atomic Model Lewis Diagram C

6. Lewis Diagrams only show VALENCE ELECTRONS
A Lewis Diagram is made up of two parts:
The element symbol
Dots that represent the electrons
Dots are ONLY allowed to go on the sides of the element symbol.
How many for Bromine? Br

7. Writing Lewis Dot Diagrams: Rules
There must be ONE electron dot on each side of the element before putting two.
What rule is this like? - HUND’S RULE!!
Here is an example: Carbon C C

8. What else? Only use s and p valence electrons
DO NOT use d or f valence electrons. Remember, these are found in between the s and p sublevels. So they are NEVER on the outside. We only want to consider the outermost electrons!
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p2

9. Se Do you hate dots yet? 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p⁴
In the element Selenium, the electron configuration is:
How many outer valence electrons does it have?
Let’s Draw it!
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p⁴ Se

10. Practice
Chlorine
Strontium
Tin

11. BE THE ARTIST. Complete the first part of the packet you picked up.
Answer all of the questions.
Work with your partner, ask them questions. If you still can’t figure it out, then ask me.
Make sure to check each other’s work!
You will turn it all in at the in a few blocks.