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Isaac proposed that the universe was mechanical and contained solid masses in motion.
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In 1803, John Dalton created his atomic theory: he theorized that all matter was made of small indivisible particles, all atoms of a certain element are identical, and that atoms can be combined into compounds and other complex molecules.
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Michael Faraday discovered electromagnetism induction in atoms through his experiments.
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In 1869, Mendeleev constructed the first Periodic Table of Elements based on atomic mass.
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He discovered the electron, the first known component of the atom. The electron is the negatively charged particle in the atom.
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Rutherford, using thin gold foil and a laser, established the discovery of the nucleus, a small, dense center to the atom.
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Soddy discovered isotopes and the half-life of radioactive substances decaying.
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Einstein proposed his theory of relativity.
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Using an oil-drop experiment, Millikan determined the mass and the charge of an electron.
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Mosely, using X-Rays, determined the charges of the nuclei of atoms. He definited atom number which became the basis of the periodic table.
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Aston used a mass spectrograph to discover isotopes, elements with different masses but still are the same element.
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He created an atomic model containing a nucleus and orbital shells of electrons.
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He discovered that electrons had a dual nature-similar to both particles and waves.
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Chadwick discovered a particle of near equal mass to the proton with no electric charge. He had found the neutron.
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He commenced the first controlled, experimental chain reaction involving releasing energy from an atomic nucleus.
