1. Warm-up 8-24-15 and 8-25-15 Partner Talk
What are inside atoms?
What is inside the nucleus of an atom?
What is the charge of a stable atom?

2. Atoms
Atoms – the basic building blocks of matter that make up everyday objects.

3. Write your name in dots Why are we doing this?
Look at it close then far away

4. Atomic Structure Atoms have 2 regions:
Nucleus – The center of the atom that contains 99% of the atom’s mass.
Electron cloud- large region that surrounds the nucleus and occupies most of the space of the atom.
Nucleus
Electron
Cloud

5. The Nucleus The nucleus contains 2 of the 3 subatomic particles:
Protons – subatomic particles that have a positive electric charge and a mass of 1amu
Neutrons – subatomic particles with a neutral (zero) electric charge and a mass of 1amu

6. Electron Cloud
The third subatomic particles is outside of the nucleus, it is in the electron cloud:
Electron – Subatomic particle with a negative electric charge and with relatively no mass. These circle the nucleus

7. Brain Pop- Atoms
stop at 1:36

8. Electrons are actually organized in the electron cloud…
The electrons are placed in energy levels called orbitals or shells.
Each orbital or shell can only hold a certain amount of electrons.
1st shell can hold up to 2 electrons
2nd shell can hold up to 8 electrons
3rd shell can hold up to 8 electrons

9. So how would we draw/model this?
Fill in the orbitals from the inside out using the 2,8,8 rule.
Ex: Aluminum has 13 electrons
First orbital would have 2 electrons
Second orbital would have 8 electrons
Third orbital would have 3 electrons

10. Let’s practice modeling an atom
Draw the atom model for Magnesium
12 protons, 12 electrons, 12 neutrons

11. Subatomic Particles
Location
Charge
Mass
Proton
Inside Nucleus
+ 1
1 amu
Neutron
Electron
Outside Nucleus
- 1
0 amu

12. Brain Pop

13. Let’s review with some Silent 4 Corners…

14. Silent Four Corners Question #1
What is the charge of a proton?
a. +1.
b. -1.
c. 0.
d. +2.

15. Silent Four Corners Question #2
When José brushes his hair with a comb he receives extra electrons, the same happens when you rub a balloon against your hair. The charges that make your hair static are:
a. positive
b. negative
c. neutral
d. there’s no charge

16. Silent Four Corners Question #3
The center of the atom contains most of its mass and it is positively charged. The center of the atom is called:
a. proton.
b. neutron.
c. electron.
d. nucleus.

17. Silent Four Corners Question #4
Which subatomic particles are found inside of the nucleus?
a. protons.
b. neutrons.
c. electrons.
d. both a and b.

18. Silent Four Corners Question #5
What area of an atom is mostly empty space?
a. the nucleus
b. the proton
c. the electron cloud
d. the neutron

19. Go to http://bit.ly/pHetBaA Click on Atom
pHet Build an Atom
Go to
Click on Atom
When done download “ 8-30 and 8-31 atom model practice”