Einsteinium
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Einsteinium is a chemical element, having the chemical symbol Es. Its atomic number (the number of protons) is 99. It has a standard atomic weight of 252 g•mol −1 and it is a solid in its elemental form.
Einsteinium is considered a member of the "Transuranic" class of elements. At a pressure of 101.325 kPa, it has a melting point of 860 °C. There is no data available regarding its boiling point.
Formally it was named for Albert Einstein, although it was initially called "pandamonium" (sic). The Ivy Mike weapons test, directed by the Panda Committee,[1] produced the 20-day 253E isotope in the fallout. Elements 99 and 100 (einsteinium and fermium) were found in debris brought back from the first H-bomb test in the Pacific by Al Ghiorso and co-workers at Berkeley in December 1952.[2][3]
References
- ↑ letter by Eric Evans in the Economist (April 19 1997, p.8)
- ↑ http://www.lbl.gov/today/2005/Jul/11-Mon/ghiobio-jump.html
- ↑ "Einsteinium", Los Alamos National Laboratory