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460 B.C. - Greek philosipher who was one of the first suggested atoms exist.
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Proust composed the Law of Constant Composition, which was that the composition of the substance is always the same no matter where it was made or found.
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Pictured atoms as extremely small and indestructable particles with with no internal substance. This led to Dalton's atomic theory,
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Discovered the electron and invented the cathode ray, which passes electric currents throught gases at a low pressure.
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Plank proposed the Plank’s constant h, explaining that the pattern of light intensity. Planck’s claim was that energy is carried in tiny units, which he named “quanta”.
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Rutherford and a few of his coworkers used massive alpha particles (atoms that have a doubly positive charge) and moved them through a thin sheet of gold foil. Most of the particles passed through the gold atoms, but a small amount deflected off at weird angles. Rutherford’s new atomic model showed that the atom is mostly empty except for the protons and neutrons inside a nucleus in the middle.
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Proposed an electron is found only in a specific orbit around the nucleus
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Millikan used a constructed valve and the “charge-to-mass ratio of an electron used by Thomson, he measured the electron’s mass. An electron carries one negative charge and the mass is 1/1840 of a hydrogen atom.
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de Brogile makes a claim that since light has waves, that particles have waves as well. He claimed that moving electron particles have properties of wave.
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Develops mathematical equations to describe motion of electrons in atoms. He created the electon cloud model and the quantum mechanical model.
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Heisenberg claims that it is impossible to know the velocity and the position of a particle at the same time.
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Discovers neutrons which have no charge and reside in the nucleus with protons.
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The World's first helicopter takes flight
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Goes into the common use for common diseases.
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Comes into first existance and a Jewish state
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The Witchhunt hearings took place in the USA.
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First satelite to orbit the earth - it was a Russian spacecraft.
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Is arrested in India for demanding independence from England
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384 B.C.- Aristotle believed that the four elements of air, earth, water, and fire could always be broken down into more matter and always be divided.
