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10cf746e54 In general, such elements up to iron are made in large stars in the process of becoming supernovas. As physical laws and processes appear common throughout the visible universe, however, scientist expect that these galaxies evolved elements in similar abundance. Abundances of the chemical elements in the Solar system. Three additional materials now accepted as elements, arsenic, antimony, and bismuth, were recognized as distinct substances prior to 1500 AD. "Recommendations" (PDF). Authority control LCCN: sh85022897 GND: 4009874-6 NDL: 00562407 . Retrieved 19 October 2006. From Boyle until the early 20th century, an element was defined as a pure substance that could not be decomposed into any simpler substance. Put another way, a chemical element cannot be transformed into other chemical elements by chemical processes. Alchemy of the Heavens. "How Stars Make Energy and New Elements" (PDF).
"Evidence for Dark Matter" (PDF). IUPAC prefers that isotope symbols be written in superscript notation when practical, for example 12C and 235U. Timaeus. "Heaviest element made again". For example, at over 1.91019 years, over a billion times longer than the current estimated age of the universe, bismuth-209 has the longest known alpha decay half-life of any naturally occurring element. The very heaviest elements (those beyond plutonium, element 94) undergo radioactive decay with short half-lives and do not occur in nature. These were however used as abbreviations in diagrams or procedures; there was no concept of atoms combining to form molecules. Chemistry of the Elements (2nd ed.). IUPAC. New York Times.