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In 1803 John Dalton created his Atomic Theory. It stated that all matter was composed of atoms, and that atoms are small, indivisible particles.
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Michael Faraday created the two laws of electrolysis.
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J. Plucker creates one of the first cathode ray tubes.
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He created organized the elements into 7 groups according to properties. This is known as the Periodic Law.
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Discovered cathode rays had certain properties such as they travel in a straight line and the impart a negative charge on an impacted item.
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G.J. Stoney proposed electricity contained negatively charged particles he called electrons.
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Wilhelm Roentgen found that chemicals near the cathode ray tubes glowed. He named them X-rays.
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J.J. Thompson discovered the mass to charge ratio of an electorn using a cathode ray tube.
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Rutherford discovered radiation emmitted from uranium and thorium. He named them alpha and beta.
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Marie Sklodowska Curie discovered radioactivty. She beleived it was the decay proccess of uranium and thorium
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Soddy discovered half lives. He also made calculations on energy released during decay.
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Nagaoka came up with the "Saturnian" model of an atom. It consisted of electrons orbiting a positively charged particle on a flat plane.
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R.A. Millikan calculated the mass and charge of an elctron.
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Ernest Rutherford discovered the nucleus was a very small, very dense, positively charged center of an atom.
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H.G.J. Moseley discovered that the atomic number of an element is equal to the number of protons in the nucleus using x-ray tubes.
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The neutron is discovered by James Chadwick using alpha particles.
