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Thales of Miletus - 600 B.C.
First philosopher and thought that everything was made of water. -
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Democritus - 400 B.C.
Believed that if you divided matter enough then you would not be able to divide it any longer. Made the first atomic model and the model was a solid sphere. -
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Aristotle - 400 B.C.
Believed that everything was made from earth, fire, water, and air. -
Sir. Issaic Newton
Discovered gravity, laws of motion, the light spectrum, and he also thought that Democritus was right to believe that everything was made from atoms. He also thought that the atomic model was a solid sphere. -
John Dalton
Believed that matter is made up of atoms that are indestructible and indivisible, all atoms of an element are identicle, atoms of different elements are different, atoms of different atoms combine to create compounds, and atoms cannot be created nor destroyed. He also thought that the atom was a sphere. -
Bacquerel
Descovered radioactivity using the Uranium Experiment. Still believed that the atom was a sphere. -
J.J. Thompson
Descovered the electron using the Cathode Ray Tube, which was a glass tube that showed a stream of electrons. his model changed and is now a circle with electrons randomly placed throughout. -
Milikan
Determined the mass and charge of an electron and used the Oil Drop experiment. HIs model was a circle with small rectangles located inside it. -
Rutherford
Descovered the nucleas and the proton using the Gold Foil Experiment. The Gold Foil Experiment was an experiment that shot particles at a sheet of gold and the majority of the particles passed through and some bounced back, which concluded that the mass of atom is located in its center. His atomic model shows that the protons form the nucleas in the center of the circle. -
Neils Bohr
Found that the electron went around neucleas in a path. His atomic model showed the protons in the nucleas was surrounded by rings that the electrons followed. -
Aston
Discovered different isotops using the Mass Spector Graph. HIs model was the same as Neils Bohr. -
Erwin Schrodinger
Creator of the Schrodinger model which predicts where electrons will be. HIs model looks similar to Neil Bohrs but has shaded areas where the electrons are predected to be. -
James Chadwick
Proved that neutrons existed. His model shows that the neucleas has both protons and neutrons.