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460 BCE
Democritus
Believed all matter is made of tiny indivisible and indestructable particles -
John Dalton
- Elements are compromised of indivisable particle caked atoms.
- All atoms of a given element are identical
- Atoms of different elements can physically mix and chemically combine
- Chemical reactions occure when atoms are seperated, joined, or rearranged
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Eugene Goldstien
-Larger than electrons -
JJ Thomson
Jj Thompson was the one who discoved electrons. The instrument he used was a Cathode Ray Tube. His model was called the plum pudding model -
Albert Einstien
Mathamatically proved the existance of atoms. Einstien also said that atoms were in constant, random motion. -
Ernest Rutherford
Using the Gold Foil experiment, Rutherford came to the important conclusion that the atom was mostly empy space and contained a positively charged nucleus. His model suggests that atoms are also unstable -
Niels Bohr
Suggested a small, dense nuecleus surrounded by orbiting electrons. Bohr also came up with the level system use to classify how many electrons are on each level -
Louis De Broglie
Said that particles could be described as waves -
Werner Heisenberg
Stated that a patricle's position and momentium cannot be known at the same time -
Erwin Schrodinger
Schrodinger's model allowed the electron to occupy 3d space, it also shows the quantinization of atom's energy levels -
James Chadwick
Discovered the Neutron, and how it was more massive than an electron
