1. Mrs. Brostrom Integrated Science C
Introduction to Atoms
Mrs. Brostrom
Integrated Science C

2. http://www.youtube.com/watch?v=jq37UQ-krW4&feature=related 0:50
Atom- the smallest part of an element that has all the properties of that element
Extremely small
Aluminum foil 50,000 atoms thick

3. What is an atom made of? Nucleus:
An atom’s central region made up of protons and neutrons (small and dense)
A subatomic particle that has a positive charge is a proton
A subatomic particle that has no charge is a neutron

4. Subatomic Particles Protons:
A subatomic particle with a positive charge
Found in the nucleus
1.7 x g g
About 1 amu
The SI unit used to express the masses of atoms is called the atomic mass unit (amu)

5. Neutron A subatomic particle with no charge Found in the nucleus
Slightly bigger than protons
Mass of about 1 amu

6. Electron a very light subatomic particle that has a negative charge
Found around the nucleus in an electron cloud.
1800 electrons = 1 proton mass
Mass is so small it is negligible (or zero)

7. Atomic number
# of protons in nucleus (also the # of electrons in a neutral atom)
Each element has a different atomic # because it has a specific # of protons

8. Mass number Equals the # of protons + neutrons (in the nucleus)
Mass # - atomic # = # of neutrons

9. An electron has a certain energy that is determined by its path around the nucleus (energy level). Electrons with different amounts of energy exist in different energy levels The higher the energy level the more energy the electrons have

10. First energy level: 2 electrons
Second energy level: 8 electrons
Third energy level: 18 electrons
Fourth energy level: 32 electrons

11. Rules for drawing atoms:
Atomic # = # protons
mass number –atomic number = # neutrons
# of electrons = # of protons
The row (period) the element is on determines how many energy level the atom will need
The group the element is in determines how many electrons will be in the outermost energy level

12. Guided Practice Protons: _____ Neutrons: _____ Electrons: ______16 S
Sulfur
32.066
Protons: _____ Neutrons: _____ Electrons: ______
How many energy shells will this have? ____
How many valence (outer) electrons does this element have? ____
Bohr Model:

13. Guided Practice Protons: _____ Neutrons: _____ Electrons: ______3 Li
Lithium
6.941
Protons: _____ Neutrons: _____ Electrons: ______
How many energy shells will this have? ____
How many valence (outer) electrons does this element have? ____
Bohr Model:

14. Guided Practice Protons: _____ Neutrons: _____ Electrons: ______10 Ne
Neon
20.180
Protons: _____ Neutrons: _____ Electrons: ______
How many energy shells will this have? ____
How many valence (outer) electrons does this element have? ____
Bohr Model:

15. The Atom Song
3:28

16. White Board Practice
Protons and neutrons are found in the ___________ of an atom

17. Electrons have a __________ charge

18. The atomic number =
The number of ______________

19. The number of protons = the number of ________

20. The mass number equals
The number of ________ + the number of _______

21. Electrons exist in ________ _______ around the nucleus