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Newton believed there were tiny particles everywhere that were constantly moving.
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John Dalton theorized that all matter consists of tiny indestructible particles and that elements are characterized by math.
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Faraday said that the number of elements separated by by passing an electrical current through molten or dissolved salt is proportional to the charge of a circuit.
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Plucker discovered the electric discharge of a cathode ray created a fluorescent glow on the walls of the tube.
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Mendeleev created the first version of the periodic table and used it to predict properties of elements that had not yet been discovered.
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Created the electromagnetic theory. He made the connection between light and electromagnetism.
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Proposed that electricity is made of negatively charged particles.
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Produced and detected electromagnetic radiation now known as as x-rays.
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Discovered the electron. Developed the plum pudding model.
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Curie discovered the radioactive elements polonium.
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Proposed a theory that energy did not flow at a steady rate but was instead delivered in packets called quanta.
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Explained that radioactivity is caused by the transmutation of elements. In 1913 he also concluded that elements can exist in different forms called isotopes.
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Discovered that cathode rays can not exist outside of discharge tubes. Used an experiment in which a thin aluminum slide was was put on the end of a cathode ray tube. The experiment showed that as the slide was pulled away the ray decreased and eventually vanished completely.
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Disagreed with Thomsons model. Believed electrons orbited outside of the atom and could not be found in a positively charged atom. He developed the Saturn Model.
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Einstein created the theory of relativity and also created the law of mass-energu equivelance E=mc^2.
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Developed the Geiger counter which is an electronic tool for measuring radioactivity.
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Millikan proposed that the charge of water is a multiple of the elementary electrical charge.
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Using the gold foil experiment he discovered the positively charged nucleus. He also found that atoms were mostly empty space and that electrons were found in this space.
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Discovered that electrons travel in orbits around the nucleus. Said that the number of electrons determine an elements properties.
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Using experiments on x-ray spectra he discovered that the atomic number of an element is equal to the number of protons in it.
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Discovered the wave nature of electrons
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Suggested electrons were arranged into orbitals which were systematically distributed throughout the electron cloud. He also defined an orbital as a region in which an electron could be found.
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Found a way to formulate quantum physics. He proposed the uncertainty principle.
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Predicted the existence of antiparticles
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Discovered the neutron and helped to develop the atomic bomb. He used nuclear fission in his experiments.
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Disintegrated Lithium atoms through the bombardment of photons.
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Lawrence invented the first particle accelerator to achieve high energy levels.
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Discovered Barium after bombarding uranium with neutrons.
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Discovered the transuranium elements.
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Fermi conducted the first controlled chain reaction and also helped to develop the first nuclear reactor.
