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John Dalton created his model of the atom in 1808. He created it after his experiment with gases. He concluded was the total pressure of a mixture of gases amounted to the sum of the partial pressures that each individual gas exerted while occupying the same space.
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experiments with cathode ray tubes showed that all atoms contain tiny negatively charged subatomic particles or electrons. Thomson proposed the plum pudding model of the atom, which had negatively-charged electrons embedded within a positively-charged "soup."
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He postulated the nuclear structure of the atom: experiments done in Rutherford's laboratory showed that when alpha particles are filled into gas atoms, a few are violently deflected, which implies a dense, positively charged central region containing most of the atomic mass.
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In 1913, Niels Bohr proposed the hydrogen atom. After his experiment based on quantities only take discrete values. Then came up with the conclusion that Electrons more around a nucleus, but onlyin prescribed orbits, and if electrons jump to a lower-energy orbit, the difference is sent out as radiation.