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Robert Boyle published this, making distinction from alchemy and chemistry. This also contained theory behind early ideas of the fundamentals of chemistry including atom, molecule and chemical reaction.
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Discovered by German alchemist Hennig Brand
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Henry Cavenish recognised properties of the element Hydrogen as a colorless, odourless gas that burns and is reactive with air.
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Antoine Lavoisier wrote a list of 33 elements, dfferentiating between metals and non-metals.
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John Dalton proposed "Dalton's Law", describing the relationship between different components in mixtures of gases. This helped future scientists to isolate gases and mixtures of gases in order for specific study.
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Jakob Berzelius developed a table of atomic weights, also introducing symbols for elements.
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Johann Dobereiner grouped elements together in 3 groups based on their properties.
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Lothar Meyer organised a table of 28 elements organized by valence.
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Dmitri Mendeleev developed a table based on atomic weights, but arranged them periodically (columns) with elements sharing properties under eachother. This table included 66 elements.
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William Ramsay discovered the Noble Gases.
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Physicist J.J. Thompson discovered electrons, small negatively charged particles in an atom.
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John Townsend and Robert Millikan determined the exact mass and charge of electrons.
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Ernest Rutherford discovered that radioactivity was produced by decaying atoms.
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Ernest Rutherford and Hans Geiger discover that electrons orbit the nucleus of an atom.
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Henry Moseley determined the atomic number of every element, modifying the Periodic Law.
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Edwin McMillan and Philip H. Abelson created neptunium for the first time, the lightest element found in uranium fission.
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In this period of time, many elements were discovered at the University of California, Berkeley. These include Plutonium, Curium, Californium, Einsteinium and Fermium.