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Aristotle disagreed and stated that matter was made of four elements water, wind, earth, fire. and others agreed.
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Democritus proposed everything in the world is made up of tiny particles. With empty space around it, also speculated that there are different shapes and sizes of atoms.
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John Dalton showed that common substances always broke down into the same elements in the same proportions. John Dalton stated that common substances always broke down to the same atoms in the same proportions. John Dalton stated the atoms could neither be created or destroyed.
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J.J. Thompson discovered the electron and found atoms were spheres packed with positive charged atoms filled with negatively charged electrons.
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Ernest Rutherford shot positively charged alpha particles at a sheet of gold foil and found out that most can go through but some bounce back. So, some particles bounce back from a dense positively charged nucleus.
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Neils Bohr discovered that electrons orbit the nucleus at fixed energies and distances, but experiments have shown that the electrons move in waves around the nucleus.
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Galileo c. Ptolemy b. Copernicus created the solar system model
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In 1926 Erwin Schrodinger expained the movement of electrons in an atom. He concluded that it was a wave of motion. He called this idea Wave Mechanics. His discovery was the first to explain the movement of electrons with visuals, and the second to explain the idea.
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Werner Heisenberg discovered it is impossible to determine the exact position and speed of electrons as they move around an atom.
