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Democritus
Democritus came up with the idea that all matter was made up of many smaller objects that he called atoms. However he had conducted no expierements and no physical proof. -
John Dalton
Dalton had agreed that all matter was mad of atoms that he stated where indestructable spheres. He also said that compounds are made up of two or more atoms. -
Dalton Model
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JJ Thomson
Thomson was the first scientist to discover the electron using an expieremental that used cathode ray tubes. His model is a bunch of electrons surrounded by a cloud of positive charges. -
JJ Thomson Model
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Robert Millikan
Robert Millikan measured the charge on an electron in 1909 by doing the oil experment -
The Oil Experement
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Ernst Rutherford
Rutherford discovered the nucleus and the protons of an atom using the gold foil expierement in whick lead him to discover the modern model of the atom. -
Gold Foil Experiment
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Neils Bohr
Borh said that outer orbit atoms could have more electrons that in orbit ones. He said knowing this could help decide an atoms property. He also siad that electrons could jump. -
Bohrs Model
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James Chadwick
Chadwick discovered the nuetron. This let scientist understand more deeply how the atom works. -
James Model
