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  John Dalton pictures atoms as tiny, indestructible particles, with no internal structure
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  J.J. Thompson discovers the electron which later leads to his "plum pudding" model.
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  Japanese physicist suggests that an atom has a central nucleus. Electrons move in orbits like the rings around saturn
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  Rutherford finds that an atom has a small, dense, positively charged nucleus
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  The electron moves in a circular orbit at fixed distances from the nucleus
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  Moving particles like electrons have some properties of waves.
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  Erwin develops mathematical equations to describe the motion of electrons in atoms.
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  confirms existence of neutrons.