1. History of the Atom

2. Greek’s
Democritus coined the term atom by saying that all things are made of atoms.
The Greek's only had 4 elements:
Earth
Wind
Fire
Water

3. Dalton’s Atomic Theory
All matter is composed of atoms
Atoms of a given element are identical in size, mass, and other properties
Atoms can not be subdivided, created, or destroyed
Law of Conservation of Matter
Law of Definite Proportion
Law of Multiple Proportion

4. Modern Atomic Theory
The same as Dalton’s Theory except we had to modify statement 2 and 3
Atoms are made of Protons, Neutrons, and Electrons
Atoms of the same element have the same number of protons but can have a different size or mass because of Isotopes

5. Joseph John Thomson
Discovered the Electron

6. Ernest Rutherford
Discovered the Nucleus (protons)