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442BC
Democritus proposed the first idea of the atom; "by convention bitter, by convention sweet, but in reality atoms and void." -
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Proposed an atomic theory with spherical solid atoms based upon measurable properties of mass.
- All matter is made up of atoms
- Atoms of the same element are the same -
Discovered the x-ray machine.
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Planck created the quantum theory: energy is not emitted constantly, but in small packages called quantum.
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Albert Einstein published the famous equation E=mc^2
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Millikan performed the oil trap experiment, which determined the charge of an electron as negative.
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Rutherford established that the nucleus was: very dense,very small and positively charged. He also assumed that the electrons were located outside the nucleus.
