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He was the inventor of the atomic theory.
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Aristotle discovered elements, this was the start of something that would later become the Periodic Table of Elements.
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He came up with the theory that all matter is composed f particles called atoms.
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He contributed theories on magnetism
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Atoms could move and cause things to move
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Atoms were just solid spheres in which they come together to build things.
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Qualitative to a quantitattive one
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Davy discovered 6 new elements that helped contribute to the Periodic Table of Elements.
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Law of definite proportions
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Faraday developed the laws of electrolysis.
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He came up with the first design or drawing of the Periodical Table of Elements.
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The founder of the Quantum Theory
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The first to identify and experiment with what were actually electron rays prod used in vacuum.
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That an atom has a nucleus.
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An atom has a dense positively charged nucleus with electrons floating randomly around the nucleus its self.
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The electrons in an atom move in spherical orbits around the nucleus.
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Discovered protons.
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Developed mathematical equations that describes the motion of an atom.
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Confirmed that an atom had electrons but they are not charged.
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Moving particles in an atom like electrons have some properties of waves.
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G.J. Stoney wrote the letter titled "Elements". Many of his theories in this letter contributed to the atomic theory.
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Roentgen discovered x-rays and how they worked.
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Becquerel discovered radioactivity that consisted of atoms.
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She discovered two radioactive elements, polonium and radium.
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Soddy observed spontaneous disintegration of radioactive elements into isotopes.
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Crookes discovered the element thallium. This element soon became apart of the Periodic Table of Elements.
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Abegg proposed the valance theory and his theory of freezing-point depression. He also discovered that inert gases had a stable electron configuration.
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Einstein's special theory of reactivity helped the law of mechanics and laws of the electromagnetic field. He also helped establish the photon theory of light.
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Geiger invented the Geiger counter to measure radiation.
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Moseley's theory that the relationship between x-rays was a function of the positive charge on the nucleus helped the Atomic Theory.
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Aston discovered the idea that modern atomic masses are based on mass spectral analysis.
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Pauli invented the Pauli Exclusion Principle that states no two electrons can exist in the same quantum state.
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Heisenberg discover a way to formulate quantum mechanics in terms of matrices.
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While conducting "atom-smashing" experiments, Cockcroft and Walton split the atom.
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Dirac discovered new productive forms of the atomic theory. He created the Dirac Equation in 1928. It describes the behavior of fermions like the electron, and predicted the existence of antimatter such as the positron