*500 BC- 1720: Alchemists used Ancient Art, during the middle Ages, to discover a substance that would change common metals to gold or silver. *442 BC: Democritus came up with the theory of atoms, and also he stated that the universe is made up of empty space and that all matter is composed of indivisible atoms. *384 - 322 BC: Aristotle developed techniques for gathering scientific facts. His progress provided the basis for scientific work more than a millennium. *1777: Lavoisier, …showed first 75 words of 524 total…

…showed last 75 words of 524 total…Uranium is bombarded by neutrons it produces smaller nuclei roughly half the size of the original Uranium nucleus. *1938- Lise Meitner realized that Hahn was splitting the Uranium nucleus, something never done before. *1951- Glen Seaborg succeeded in making man-made elements first. *1964- Murray Gell-Mann and George Zweig recommended the idea of quarks called up, down, or strange, unruffled of mesons and baryons, with spin 0.5 and electric charges of 2/3, -1/3, and -1/3 in that order.