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By the end of 1860 around 60 elements had been discovered on the periodic table
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Dmitri Mendeleev produced a table based on atomic weights but arranged 'periodically' with elements with similar properties under each other. His Periodic Table included the 66 known elements organized by atomic weights.
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William Ramsay discovered the Noble Gases.
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John Newlands arranged the known elements in order of atomic weights & observed similarities between some elements
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Johann Dobereiner developed groups of 3 elements with similar properties