1. BOHR Models and Valence Electrons
Ms. Millimet
August 19, 2013

2. Entrance procedure Enter the room silently
Pick up papers you need for class
Sit down at your table:
Write down homework
Get out homework from last night in first 2 minutes – Check with KEY
Start DO First

3. Objectives
Create a Bohr model for an atom that represents elements 1-18.
Determine the number of valence electrons for any atom based on its a Bohr model of that atom.

4. Homework Review: Questions 5 and 6
What evidence do we have that supports our claim that these models represent Phosphorus and Neon? (Think: Atomic Number, Mass, Protons, etc.)

5. Bohr Model Practice Go over DO First Bohr Models Remember steps:
Draw nucleus and write number of protons and neutrons
Draw energy levels
Draw electrons based on rule
1st energy level – max 2 electrons
2nd energy level – max 8 electrons
3rd energy level – max 8 electrons

6. Valence Electrons
Valence electrons are the electrons that are located in the outer-most energy level
Valence electrons determine the physical and chemical characteristics of an element.
Bohr models are extremely helpful in determining how many valence electrons an element’s atoms have.

7. Valence electrons These electrons
Go back into Bohr models on Do First and circle the valence electrons!

8. Valence Electrons
How many valence electrons does Magnesium have

9. Valence Electrons
How many valence electrons does Neon have?

10. Practice
APE MAN and draw a BOHR Model for the following elements. Label the number of valence electrons the atom has for:
Chlorine
Sodium
Boron

11. BOHR Model UnFair Game!
Create a Bohr model for an atom that represents elements 1-18.
Determine the number of valence electrons for any atom based on its location on the Periodic Table or a Bohr model of that atom.
Review: atomic structure, APE MAN

12. Unfair Game Only playing for 15 minutes  Prizes:
5 MERITS
HOMEWORK PASS
RESTROOM PASS
Popsicles sticks will be pulled
Write down answers in empty space under vocabulary box.

13. Question 1
How many protons are in a hydrogen atom?
1 proton

14. Question 2
How many neutrons are in a fluorine atom?

15. Question 3
How many protons, electrons, and neutrons are in one atom of argon?

16. Question 4
What element’s atom is represented below?
Sodium

17. Question 5
How many valence electrons does this element have? 1

18. Question 6
A student creates a model of a helium atom. Which subatomic particles – and how many of each - would be found in the nucleus?

19. Question 7
Which element’s atom is pictured here?
carbon

20. Question 8
How many valence electrons does this atom have? 2

21. Question 9
How many valence electrons does one atom of Fluorine have?

22. Question 10
How many valence electrons does one atom of Magnesium have?

23. Question 11
electrons

24. Question 12
Which subatomic particle determines an atom’s identity as a certain element?
electrons

25. Question 13
Which subatomic particles are used to calculate the atomic mass?
electrons

26. Question 14
What is the atomic mass of this atom?
electrons

27. Question 15
What is the atomic number of this atom?
electrons

28. Question 16
Which element is identified by having 16 protons?

29. More Practice and Exit Ticket
Complete the practice and HW worksheet silently and independently
Finish for HW
With 8 minutes left – Exit Ticket!
Put notes in your study buddy binder
Take out periodic table and red pen to trade and grade