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nHendiscovered some rare-earth elements.
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nHenhad a daughter who went on to be the first woman in Sweden to earn andoctoral degree in the sciences.
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Andnhe had a grandson who earned a Nobel Prize in Physiology!
Andnhe had a grandson who earned a Nobel Prize in Physiology!n
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nPernTeodor Cleve was a Swedish chemist and geologist who was born on thisndate in 1840. As he studied rocks and minerals, he tried to figurenout what elements made them up.
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Annearlier scientist, Carl Mosander, had discovered that a mineralncalled cerite was made up of the elements cerium, lanthanum, andndidymium. The latter two elements were Mosander’s discoveries, and sonhe got to name them. Lanthanum and didymium were entered into thenPeriodic Table of Elements of the day, and given appropriatenabbreviations (La and Di). But…it turned out that Mosander wasnwrong about didymium being an element.
Annearlier scientist, Carl Mosander, had discovered that a mineralncalled cerite was made up of the elements cerium, lanthanum, andndidymium. The latter two elements were Mosander’s discoveries, and sonhe got to name them. Lanthanum and didymium were entered into thenPeriodic Table of Elements of the day, and given appropriatenabbreviations (La and Di). But…it turned out that Mosander wasnwrong about didymium being an element.n
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nClevenwas able to prove that didymium could be broken down into twondifferent elements. Later scientists were able to separate the saltsnof the two new elements, which are named neodymium (“new” dymium)nand praseodymium (“green” dymium).
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| Neodymium |
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| Praseodymium |
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nThisnis not an embarrassing chapter of science! This story does not proventhat Mosander was a careless or ignorant scientist! He did the bestnhe could with the equipment he had, and he made many discoveries thatnstill stand today, including three elements. Instead of being annembarrassing chapter of science, this is a great story—it shows,nonce again, that science is self-correcting, that later discoveriesnoften refine older discoveries, and that scientists are able to reachnnew heights of understanding partly because they are figurativelynstanding on the shoulders of great scientists of the past!
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nOurnbirthday boy, Cleve, also discovered two more new rare-earthnelements: holmium and thulium.
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nAlsonon this date:
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nAnniversary of a riot over a silent film
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nCarnival de Oruro in Bolivia
