1. MT 2 Chemical Bonds
How to Draw
Lewis Dot Structures

2. Lewis Structures What is a Lewis Structure?
A simplified way to represent an atom & its valence electrons
Has 2 Parts
Atomic Symbol of Element
Dots representing the electrons surrounding it

3. Lewis Structures Steps
Find your element on the periodic table.
Determine the number of valence electrons.
This is how many electrons you will draw.

4. Lewis Structures Find out which group (column) your element is in.
This will tell you the number of valence electrons your element has.
You will only draw the valence electrons.

5. Groups Group 18 = 8 electrons Group 1 = 1 electron
Except for He, it has 2 electrons
Group 2 = 2 electrons
Each column is called a “group”
13, 14, 15, 16, 17
Each element in a group has the same number of electrons in their outer orbital, also known as “shells”.
The electrons in the outer shell are called “valence electrons”

6. C Lewis Structures Write the element symbol.
Carbon is in the 14th group, so it has 4 valence electrons.
Starting at the right, draw 4 electrons, or dots, counter-clockwise around the element symbol. C

7. C Lewis Structures Check your work.
Using your periodic table, check that Carbon is in the 14th group.
You should have 4 total electrons, or dots, drawn in for Carbon. C

8. C Lewis Structures Now, try these elements on your own: H P Ca Ar ClAl C

9. H Lewis Structures On your paper, try these elements on your own: H PCa Ar Cl Al H

10. P Lewis Structures On your paper, try these elements on your own: H PCa Ar Cl Al P

11. Ca Lewis Structures On your paper, try these elements on your own: H PAr Cl Al Ca

12. Ar Lewis Structures On your worksheet, try these elements on your own:P Ca Ar Cl Al Ar

13. Cl Lewis Structures On your worksheet, try these elements on your own:P Ca Ar Cl Al Cl

14. Al Lewis Structures On your paper, try these elements on your own: H PCa Ar Cl Al Al

15. What do I do now??
Complete the Lewis Structure Worksheet You should know how to draw Lewis Structures for the first 20 elements.