1. 12.1 Atomic Structure

2. Subatomic Particles
Subatomic particles are particles that are inside the atom.
proton
neutron
electron

3. Protons positive charge located in the nucleus (center of the atom)
accounts for some of the mass of an atom
always the same for atoms of the same element

4. Protons
# of protons = atomic number

5. Check in: How many protons are in the atoms of the following elements?Al
Do the number of protons in an atom ever change?

6. Neutrons neutral charge located in the nucleus
account for the mass of an atom

7. Electrons negative charge located in the electron cloud
account for the volume of the atom

8. Comparing Particles
protons and neutrons are MASSIVE compared to electrons
electrons mass is so small we tend to ignore it
to determine the mass of an atom (mass number)
mass # = protons + neutrons

9. Atomic Forces REVIEW: opposites attract likes repel
Protons and Electrons:
opposite charges – attract
attraction holds electrons onto the outside of the atom

10. Check-in:
If an atom of oxygen has 8 protons and 7 neutrons, what is its mass?
If an atom of chlorine has a mass number of 36, how many neutrons does it have?

11. Good Morning! Take out a notebook Take out your lab notebook
Back page has periodic table!
Take out your homework packet
Begin working on HW packet pg. 3-4

12. Tuesday, February 24, 2015
Learning Target: I can identify subatomic particles and their properties in an atom
Today:
Review Subatomic particles
Review Exit Question
Isotopes, Ions, and more!
Coming up:
Quiz Thursday (atomic structure)
HW Packet pages 2-4 due Thurs

13. Review of Subatomic Particles
Protons – positive, in the nucleus, massive
Neutrons – neutral, in the nucleus, massive
Electrons – negative, outside nucleus, very tiny mass, take up space
Atomic # = # protons
Mass # = # protons + # neutrons

14. Exit Question PP N How many protons? 2 What element? Helium (He)
How many neutrons? 1
How many electrons (if neutral)?** 2 (same as P)

15. Atomic Forces
Think: If like repel, then why are the protons together in the nucleus?
The strong force holds protons together in the nucleus.

16. VIDEO: Just How Small is the Atom???

17. Varying Subatomic Particles
PROTONS NEVER CHANGE FOR ATOMS OF THE SAME ELEMENT!
electrons and neutrons, however, CAN change

18. Isotopes
Isotopes are atoms of the same element that have different number of neutrons.
If the number of neutrons change, the mass of the atom changes
mass # = protons + neutrons

19. Ions ions are atoms that have a charge
atoms lose or gain electrons to change the overall charge of the atom

20. Review Groups Tara, Cole C, Chris, Avery - Station 1
Maddie, Jean, Ayrias - Station 3
Eli, Sam, Brianna, Herlinda - Station 5
Juan, Anna, Devon, Gilberto - Station 7
Lysandra, Mandy, Amanda - Station 9
Mohamed, Lizzy, Randy - Station 11
Jackie, Jazz, Andre - Station 13
Dylan, Tas, Kalie - Desks
Cole F, David, Zach - Desks

21. Good Morning! Take out your notes from yesterday
Turn in your Lab 12a half sheet
Take out your Lab Notebook
Turn to page 82

22. Wednesday, February 25, 2015
Learning Target: I can describe the structure of an atom
Today:
Review Isotopes and Ions (5 min)
Atom building game (30 min)
Work time on homework packet (rest)