europium

europium

[yoo-roh-pee-uhm, yuh-]
noun Chemistry.
a rare-earth metallic element whose salts are light pink. Symbol: Eu; atomic weight: 151.96; atomic number: 63.

Origin:
1900–05; Europe + -ium

Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source Link To europium
Collins
World English Dictionary
europium (jʊˈrəʊpɪəm)
 
n
a soft ductile reactive silvery-white element of the lanthanide series of metals: used as the red phosphor in colour television and in lasers. Symbol: Eu; atomic no: 63; atomic wt: 151.965; valency: 2 or 3; relative density: 5.244; melting pt: 822°C; boiling pt: 1527°C
 
[C20: named after Europe + -ium]

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
American Heritage
Medical Dictionary

europium eu·ro·pi·um (yu-rō'pē-əm)
n.
Symbol Eu
A rare-earth element used as a neutron absorber in nuclear research. Atomic number 63; atomic weight 151.96; melting point 822°C; boiling point 1,596°C; specific gravity 5.244; valence 2, 3.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Cite This Source
American Heritage
Science Dictionary
europium   (y-rō'pē-əm)  Pronunciation Key 
Symbol Eu
A very rare, silvery-white metallic element that is the softest member of the lanthanide series. It is used in making color television tubes and lasers and as a neutron absorber in nuclear research. Atomic number 63; atomic weight 151.96; melting point 826°C; boiling point 1,439°C; specific gravity 5.259; valence 2, 3. See Periodic Table.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source
Encyclopedia Britannica
Encyclopedia

europium

(Eu), chemical element, rare-earth metal of the lanthanoid series of the periodic table; it is the least dense, softest, and most volatile member of the lanthanoid series. The element was discovered (1896) by Eugene-Anatole Demarcay and named for Europe. One of the least abundant rare earths, it occurs in minute amounts in many rare-earth minerals such as monazite and also in the products of nuclear fission. Europium is usually separated by reducing it to the +2 oxidation state and precipitating it with sulfate ions. The primary use of europium has been for research purposes. Because it readily absorbs thermal neutrons, it may prove to be of use in nuclear-reactor control rods. It has been used as a phosphor activator, as a component of certain electronic materials, and as an agent in the manufacture of fluorescent glass. The metal has been prepared by electrolysis of the fused halides and by reduction of its oxide by lanthanum metal followed by distillation of the europium metal. It quickly reacts in air, oxygen, and water. Both of its naturally occurring isotopes are stable: europium-151 (47.8 percent) and europium-153 (52.2 percent).

Learn more about europium with a free trial on Britannica.com.

Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
Cite This Source
Copyright © 2014 Dictionary.com, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature