1. How to Draw Lewis Structures

2. What are Lewis Structures?
Simplified Bohr diagrams which only consider electrons in outer energy levels.
The Lewis structure consists of the element symbol surrounded by “dots” to represent the number of electrons in the outer energy level.

3. What is a valence electron?
A valence electron is an electron in the outermost shell of the atom.
An electron in the outer shell of an atom that can be lost to or shared with another atom to form a molecule.
Molecules will be discussed later when learning chemical reactions.

4. How are Lewis Structures and Bohr Models Alike?
They both represent the number of electrons on the valence shell – the outer shell
The Lewis structure is more simple than the Bohr model

5. How are Lewis Structures and Bohr Models Different?
The Bohr model places electrons in energy levels (represented by rings) around the nucleus
The Lewis structure places the electrons around the chemical symbol. The number of valence electrons is placed in a square design.

6. Lewis Structures Find the element on the periodic table.
Determine the number of electrons in the last (valence) shell.
This is how many electrons you will draw.

7. Lewis Structures Find out which group (column) your element is in.
The group # = the # of valence electrons of the element.
You will only draw the valence electrons.

8. Groups - Review Group 8 = 8 electrons Group 1 = 1 electron
Except for He, it has 2 electrons
Group 2 = 2 electrons
Each column is called a “group”
3, 4, 5, 6, 7
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”

9. Lewis Structures Steps
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

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

11. Try these elements on your own:P Ca Ar Cl Al

12. Videos of Lewis Structures
Bozeman science
Steps to Drawing Electron Dot Diagrams

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

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

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

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

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

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

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

21. Chemical Bonding
Chemical Bonds Video Quiz

22. Video Answer Key