| Europium, symbol Eu, is a soft, silvery metallic element
that is among the least abundant of the rare earth elements. Europium is
in the lanthanide series of the periodic table. Europium has an atomic
number of 63.
Europium was discovered spectroscopically by the French chemist Eugène
Demarçay in 1896. It ranks 50th in order of abundance
of the elements in
the earth's crust; it occurs in monazite, bastnaesite, and other
rare earth
minerals, as well as in fission products of uranium, thorium, and plutonium.
Europium is used as a phosphor activator. The screen of a color
television
tube is treated with europium, which, when bombarded with electrons,
produces the color red. Because it readily absorbs neutrons,
europium is
used in the control of nuclear fission in reactors . |
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