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101
Thales - 600 BC
- believed everything was made of water
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101
Democritus - 460 BC
- first man to believe the atom was made of a circle, thought of the atom
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101
Aristotle - 400 BC
- believed that everything was made of Earth, water, air, and fire
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Sir Isaac Newton - 1670
- discovered gravity, laws of motion, and light spectrum
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John Dalton - 1807
- stated matter is atoms, indivisible, and indestructable. All elements are identical atoms and different elements are different
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Becquerel - 1896
- discovered radioactivity
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JJ Thompson - 1897
- discovered electron and did cathode ray experiment
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Robert Millikan - 1909
- oil drop experiment and determined the charge and the mass of the electron and charge
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Rutherford - 1911
- discovered nucleus and proton with gold foil experiment
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Niels Bohr - 1913
- discovered how electrons travel around nucleus
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Francis Aston - 1919
- discovered mass spectograph and discovered isotopes
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Erwin Schrodinger - 1926
- created the Schrodinger model and had the electron clouds
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James Chadwick - 1932
- created plum pudding model and proved that neutrons exist