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Democritus suggested matter could not be infinitely divided.
Came up with the term "atom"
(460-370 B.C.) -
Disagreed with Democritus' idea that atoms move through empty space.
Denied existence of atoms due to personal beliefs
(384-322 B.C.) -
"Atoms are the smallest particles of matter and are indevisible and indestructable"
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Needs to determine the mass of single cathode ray particle
Concludes that the mass of the particle was much less than the Hydrogen atom, which disproved Dalton's theory that atoms were indivisible.
Discovers electons
(1856-1940) -
Develops oil drop apparatus to determine the charge of the electron
discovers that and elecron is equal to -1
(1868- 1953) -
Concludes that there is a nucleus
Discovers Protons and Neutrons
