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Period: Oct 10, 1001 to
Atom timeline
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Oct 9, 1417
DEMOCRITUS
He preformed no experiments, had only the slimest piece of evidence for postulating the existance of atoms. -
Period: Oct 9, 1417 to
THe history of Matter
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John Dalton
Determined that each chemical element is cohostof a unique type of atom. That the atoms defered by their masses. -
William Crooke
Did experiments with a glass vaccume tube. The glass tube had two peices of metal called electrodes. The other cathode has a negative charge, one electrode, and one posotive charge. The were called cathode rays. -
George Stoney
He discovered the alpha particle ,but had no further proof of it. -
J.J. Thompson
Placed a magnet beside the cathode ray. The beam is beant in the opposite direction of the magnet. Proton is the positive particle in the nucleus. Suggested a modle of the atom as a sphere of positive matter in which electrons are positition by electrostatic forces. -
Period: to
History of the Atom
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Earnest Rutherford
Ran tests on the Apha Particle.Studied from J.J. Thompsons work and wanted to prove it. He predicted that alpha paricles would go through a sheet of gold. Then after that he discovered the nucleous since the alpha particles would refract back to him. -
Niels Bore
Developed an explanation oatomic structyre that unlined regularites of the perdidic table of elements his atomic modle had orbits around the nucules.
