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460 B.C. Democritus, an Ancient Greek Philosopher created the first atomic theory.
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Delcaration of Independence
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Came up with the Law of Constant Composition, which stated that the composition of a substance is always the same.
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In 1803, John Dalton came up with the atomic theory that said, all matter was composed of small indivisible particles termed atoms, atoms of a given element possess specific characteristics and weight, and there are three types of atoms which are simple, compound, and complex.
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Civil War
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Henri Becquerel discovered natural radioactivity and showed that the rays emitted by uranium, caused gases to ionize aand this dependedon the type ofX-ray in and could be deflected by electric or magnetic fields.
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In the year of 1897, J.J. Thomson discovered the electron and created the cathode ray, which passes electric currents throught gases at a low pressure.
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Paper Clip invented
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Plank proposed that energy had a resonator of frequency (v) is hv where (h) is a universal constant, which is now known as Planck's constant.
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Wilbur and Orville Wrightsucceeded in flying an airplane they built for 12 seconds
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Rutherford came up with a new atomic model that showed the atom is almost empty but protons and neutrons are inside a nucleus located in the middle.
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Introduced that electrons orbit around the nucleus of an atom.
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July 28, 1914 - November 11,1918
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Millikan found out what the charge was carried by an electron by using the elegant "falling-drop" method and that it was true for all electrons.
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Louis de Broglie claimed that particles and electrons all have waves, just like light.
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Heisenberg stated that you cannot give an electron a position in space at a given time, nor follow it in its orbit,
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With the help of some of Albert Einsteins notes, Erwin Schrödinger began to think of ways to describe how an electron moves in a wave-like motion. In the year 1926, he proposed a theory using Neil Bohr's atomic model, which then became known as Schrödinger's wave equation
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The Great Depression
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Chadwick discovers neutrons exist and come to the conclusion that they are in the nucleus with the protons and have no charge.
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September 1, 1939 -September 16, 1945
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NASA is founded on October 3, 1958
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Kennedy Assassination
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Apollo 11 Moon Landing
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384 BC. Aristotle, an Ancient Greek philosopher and scientist believed that air, earth, water, and fire ccould be broken down into more matter.
