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Democritus hypothesized that atoms cannot be destroyed, differ in size, shape and temperature, are always moving, and are invisible.
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He thought that all materials on Earth were not made of atom
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Atoms are neither created nor destroyed in a chemical reaction.
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It states an element is one of a kind (aka pure) because all atoms of an element are identical.
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This law states that a compound is composed of exact proportions of elements by mass regardless of how the compound was created.
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The hypothesis states that at the same temperature and pressure, equal volumes of gases contain the same number of molecules or atoms.
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Disovered that cathode rays had the following properties: travel in straight lines, cause glass to fluoresce, and impart a negative charge to objects they strike
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discovered this phenomenon while experimenting with uranium and a photographic plate.
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Used a CRT to experimentally determine the charge to mass ratio od an electron
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Studied uranium and thorium and called their spontaneous decay process "radioactivity".
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used the idea of quanta (discrete units of energy) to explain hot glowing matter.
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Calculates how the movement of molecules in a liquid can cause the Brownian motion.
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He established that the nucleus was: very dense,very small and positively charged
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Using x-ray tubes, determined the charges on the nuclei of most atoms.
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Developed an explanation of atomic structure that underlies regularities of the periodic table of elements.
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Discovered that electrons had a dual nature-similar to both particles and waves.
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Described atoms by means of formula connected to the frequencies of spectral lines.
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Viewed electrons as continuous clouds and introduced "wave mechanics" as a mathematical model of the atom.
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Using alpha particles discovered a neutral atomic particle with a mass close to a proton aka the neutron
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