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Democritus
democritus
Democritus lived form 460 B.C to 370 B.C. He came up with the first atomic theory, and he said all matter came from atoms. -
John Dalton
John Dalton Biography
John Dalton was born in september 6, 1766 and died July 26, 1844. He agreed with democritus that all matter is made of atoms, He used experiments and created a table that showed the different masses of atoms. -
J.J Thomson
J.J. thomson
J.J Thomson was born in 1856 and died in 1940. he won the 1906 Nobel Price in Physics. He found that there was a positive and negative portion of atoms. He did experiments using his cathode ray and created a chocolate chips cookie model. -
Ernest Rutherford
Ernest Rutherford was born in 1871 and died in 1937. He was a former student of Thomson and proved Thomson's theory wrong. He found that the protons were in the nucleus. He also proved most of tha atom is empty space. He did his experiments use his model called the planetary model. -
Niels Bohr
Niels Bohr was born in 1885 and died in 1962. He refined Rutherfords. He proposed electrons orbited the nucleus without losing energy and that they could move only in fixed orbits of specific energies. -
James Chadwick
James Chadxick was born in was born in 1891 and died in 1974. He figured out about the existence of the neurton. He also said there was the same number of protons, but a different number of nuetron.
