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  c. 400 - 370 BCE a Greek scientist and philosopher, named Democritus theorized a small, indivisible, things. Later called Atoms
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  Developed the Laws of Motion.
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  Proposed the Oxygen theory of combustion
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  proposed the "Atomic Theory" where atoms were based on properties of mass.
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  Studied what happened to solutions when elextricity was applie. Coined the term electrolysis.
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  Built the cathode ray tube, that was used in later experiments.
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  Arranged the known elements into 7 specific groups.
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  proposed the idea that magnetic and electric fields filled the void between atoms.
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  Discovered various properties about the cathode ray tube, like how they travel in a straight line, and cause glass to fluoresce.
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  Used a CRT to study canal rays.
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  Said the electricity was made of discrete negative particles.
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  Found "X-rays" coming from a CRT that didn't get defleted by a magnetic field.
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  experimentally determined the charge to mass ratio of an electron,
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  Found and named Alpha and Beta particles
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  discovered and coined the term "radioactivity"
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  Used quanta to explain hot glowing matter
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  Developed the equation E=mc2
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  Determined the charge carried by an electron
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  Found that the nucleus was very dense and very small. Also assumed that electros were located outside the nucleus.
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  Proposed Principle of Indeterminancy
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  introduced "wave mechanics"
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  Discovered neutral atomic particles
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  Made groundbreaking contributions to quantum theory. Had multiple theories.
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  Developed an explanation of atomic structure
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  18 days. (2015, September 7). Retrieved September 17, 2015.
 Buescher, L. (2004). Atomic Structure Timeline. Retrieved September 17, 2015.History of atoms. (2004, November 1). Retrieved September 17, 2015.
