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John Dalton pictures atoms as tiny, indestructible particles, with no internal structure.
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J.J. Thomson, a British scientist discovers the electron. The later leads to his "plum-pudding" model. He pictures electrons embedded in a sphere of positive electrical charge.
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A Japanese physicist, suggests that an atom has a central nucleus. Electrons move in orbits like the rings around Saturn.
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New Zealand physicist Ernest Rutherford finds that an atom has a small, dense, positively charged nucleus. Electrons move around the nucleus.
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Niels Bohr changed Rutherford's model to include newer discoveries about how the energy of an atom changes when it absorbs or emits light.
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In Niels Bohr's model, the electron moves in a circular orbit at fixed distance from the nucleus
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Luis de Broglie proposes that moving particles like electrons have some properties of waves. Within a few years, experimental evidence supports the idea.
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Erwin Schrödinger develops mathematical equations to describe the motion of electrons in atoms. His work leads to the electron cloud model.
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In 1926 the Austrian physicist Erwin Schodinger used these new results to device and solve a mathematical equation describing the behavior of the electron in a hydrogen atom.
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An English physicist, confirms the existence of neutrons, which have no charge. Atomic nuclei contain neutrons and positively charged protons.