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The Alchemists created the atomic theory. This theory states that all matter is composed of particles called atoms.
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Democritus and his mentor Leucippus discovered the first atom theory. They believed that everything is made of tiny things that never get deleted, they can only be moved or changed.
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Plato introduced the atomic theory in which ideal geometric forms serve as atoms. According to which atoms broke down mathematically into triangles, such that the form elements had shapes.
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Aristotle discovered that there were elements related to atoms. These elements were air, water, earth, and fire.
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Robert Boyle discovered that atoms must exist based on the relationship between pressure and volume of gas.
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Lavoisier found that the total mass of products and reactants in a chemical reactions is always the same. This led to the theory of the law of conservation of mass.
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Created by John Dalton.
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John Dalton was the first scientist to explain the behavior of atoms in terms of the measurement of weight.
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Dmitri Mendeleev created the first periodic table of elements. He concluded that there were still more elements to find and added to the table.
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J.J. Thomson discovered the electron. He is known for the Thomson atomic theory.
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The curies discovered a ew element, which would prove that the atoms of one element at least were not indivisible.
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Created by J.J. Thomson.
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Robert Millikan created a better method for measuring an electric charge.
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Ernest Rutherford re-constructed the nuclear structure of the atom. He also discovered alpha and beta rays and proposed the laws of radioactive decay.
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created by Neils Bohr.
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Niels Bohr created the Atomic Model. The Bohr model shows the atom as a small, positively charged nucleus surrounded by orbiting electrons.
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He created the Mosely law. Moseley’s law is an empirical law concerning the characteristic x-rays that are emitted by atoms.
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Created by Werner Heisenberg.
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Werner Heisenberg discovered the uncertainty principle. This states that it is impossible to specify the precise position and momentum of a particle at the same time.
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Albert Einstein created the Manhattan Project. This was a research project funded by the U.S that led to the creation of the atomic bomb.
