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  -Originated the concept of the Atom.
 -Did not perform any experiaments
 -His ideas were based on theory since no experiament was conducted
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  -Father of the atomic theory
 -1) All matter is made of atoms. Atoms are indivisible and indestructible. 2) All atoms of a given element are identical in mass and properties 3) Compounds are formed by a combination of two or more different kinds of atoms. 4) A chemical reaction is a rearrangement of atoms.
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  -Studied canal rays and found that they were connected with protons
 -Announced that cathode rays were negatively charged particles now called electrons.
 --Plum pudding model, believed electrons were like plums.
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  -Began experiments to determine the electric charge of electrons.
 -Performed oil drop experament.
 -1916 he determined the mas of electrons
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  -Helped develop nuclear atomic model of the atom
 -Worked with J.J Thompson
 -He did the gold foil experament and discovered the nucleus.
 - Renamed canal rays to protons in 1920
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  -Liquid Droplet theory, understanding of the mechanism of nuclear fission
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  -Looked at electrons as continuous clouds.
 -Introduced "Wave mechanics" as a different model of the atom
 -Developed the probability function for the hydrogen atom
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  -Using alpha particles, he introduced a neutral atomic particle with the mass that is similar to a proton.
 -Discovered neutron
 -worked with rutherford