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Democritus said all matter was made of unbreakable things called atoms.
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John Dalton created three universal rules: all matter is made of atoms, atoms can’t be divided or destroyed, and all compounds are made of 2 or more types of atoms.
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Dmitri Mendeleev sorted all the atoms and put them into a chart called the periodic table.
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Eugene Goldstein discovered protons on the atom.
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J.J. Thomson was able to discover electron surrounding the atom.
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Max Planck created the quantum theory.
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Robert Millikan was able to measure the charge of electrons in an atom.
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Ernest Rutherford believed that the nucleus was surrounded by empty space and electron circling it.
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Neils Bohr believed that the nucleus was positively charged and electrons orbited it in rings.
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Erwin Schrödinger created quantum mechanical models that show the area of an atom that could contain an electron.
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James chadwick discovered that there were neutrons in the atoms.
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Werner Heisenberg created quantum mechanics.
