1. Atomic Structure

2. Outside nucleus in electron cloud
3 Parts of the Atom:
Subatomic Particle
Relative Mass
Charge
Where Found
Proton 1 +1
In Nucleus
Neutron
0(neutral)
Electron -1
Outside nucleus in electron cloud

3. Key Points:
The nucleus of an atom contains roughly 99.9% of the mass of an atom.  
More than 99.9% (that's a popular number) of the atom is "empty space" occupied by moving electrons (which weigh very little). If you could make an atom as big as a football stadium, then its nucleus would still be as small as a marble.  
We cannot predict the exact location—only a probable location—of an electron at any given time.
Electrons in the outer energy levels(called valence electrons) are involved with forming compounds.

4. What is the relative mass of a proton?1 2 3

5. What is the charge of an electron?
Positive
Negative
Neutral

6. What subatomic particle has a relative mass of 1 and a (+) charge
Electron
Proton
Neutron

7. What subatomic particle(s) are found inside the nucleus?
Electron
Proton
Neutron
Protons and Neutrons
Protons and Electrons

8. Each energy level can hold a specific # of electrons:

9. How many electrons are found in the 3rd energy level?2 8 10 18

10. I hope we get a handout with all these names!!
How do we know so much about the atom? Who discovered the atom? How long ago?
It started along time ago with a guy named Democritus and went through several changes until a couple of dudes named de Broglie and Schrodinger
I hope we get a handout with all these names!!

11. I look pretty good for a dude 2400 years old!!!
In Greek, the prefix "a" means "not" and the word "tomos" means cut. Our word atom therefore comes from atomos, a Greek word meaning uncuttable.

12. John Dalton: early 1800’s

14. JJ Thomson--1897 Plum Pudding Model But the atom is Neutral!!!!
While studying electric discharge in Cathode-ray tubes, Thomson discovered the electron!!!

15. What Rutherford Expected
Ernest Rutherford--1908
Rutherford’s Gold Foil Experiment
In an attempt to build on Thomson’s model, I discovered some amazing stuff!!!
What Rutherford Expected
Actual Results
Rutherford’s Model

16. Rutherford’s Atomic Model
Notice 2 things:
Atom is made up of mostly empty space.
Electrons are scattered randomly!
Rutherford’s Atomic Model

17. Nucleus
Electrons
Neils Bohr--1913

18. Bohr Model of the Atom The Bohr Model has the following features:
There is a nucleus(Rutherford’s Discovery)
The electrons move about the nucleus in “stationary, stable states”(later referred to as orbits)!

19. The Wave Model of the Atom

20. Discovery of the neutron
In 1932, Sir James Chadwick, working to interpret the results of other scientists, discovered the neutron!!!
James Chadwick--1932

21. Which scientist is credited with the discovery of the electron?
Dalton
Thomson
Rutherford
Bohr

22. Dalton Thomson Rutherford Bohr
Which scientist is credited with the discovery of the “orbital” motion of the electrons around the nucleus?
Dalton
Thomson
Rutherford
Bohr

23. Which scientist is credited with the discovery of the nucleus?
Dalton
Thomson
Rutherford
Bohr

24. Which scientist is credited with the 1st Atomic Theory?
Dalton
Thomson
Rutherford
Bohr

25. I’m going to find Mr. Rodgers
That’s a bunch of stuff!!!
Let’s wrap this up!!!
Mrs. Hardeman
Mrs. Wolcott
Mrs. Hatfield
Mrs. Elliot

26. Democritus/Dalton

27. Chemical Symbols
Shorthand method of writing the names of the elements on the period table.
All symbols either have 1 or 2 letters.
If one letter, then that letter is capitalized.
If two letters, then first letter is capitalized, second letter is lowercase.
H—Hydrogen C-Carbon
Cu—Copper Mg—Magnesium
Cl—Chlorine K-Potassium

28. Classwork
P #1-5