/yoo roh"pee euhm, yeuh-/, n. Chem.
a rare-earth metallic element whose salts are light pink. Symbol: Eu; at. wt.: 151.96; at. no.: 63.
[1900-05; EUROPE + -IUM]

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 (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 Eugène-Anatole Demarçay 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).

      In its predominant oxidation state of +3, europium behaves as a typical rare earth, forming a series of generally pale pink salts. The Eu3+ ion is paramagnetic because of the presence of unpaired electrons. Europium possesses the most easily produced and stablest +2 oxidation state of the rare earths. Europium(+3) solutions can be reduced by zinc metal and hydrochloric acid to give Eu2+ in solution; the ion is stable in dilute hydrochloric acid if oxygen from the air is excluded. A series of white to pale yellow or green europium(+2) salts are known, such as europium(II) sulfate, chloride, hydroxide, and carbonate. The halides may be prepared by hydrogen reduction of the anhydrous trivalent halides.

atomic number
atomic weight
melting point
822° C
boiling point
1,527° C
specific gravity
5.244 (25° C)
oxidation states
+2, +3
electronic config.
[Xe]4f 75d06s2

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Universalium. 2010.

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  • Europium — (pronEng|jʊˈroʊpiəm) is a chemical element with the symbol Eu and atomic number 63. It was named after the continent Europe. Characteristics Europium is the most reactive of the rare earth elements; it rapidly oxidizes in air, and resembles… …   Wikipedia

  • Europium — Samarium ← Europium → Gadolinium …   Wikipédia en Français

  • europium — [ ørɔpjɔm ] n. m. • 1901; de Europe ♦ Chim. Élément atomique (Eu; no at. 63; m. at. 151,96) de la série des lanthanides. ● europium nom masculin (de Europe) Métal du groupe des lanthanides ou terres rares, élément chimique de symbole Eu. (C est… …   Encyclopédie Universelle

  • Europium — Eu*ro pi*um, n. [NL.; Europe + ium, as in aluminium.] (Chem.) A metallic element of the rare earth group (Lanthanide series), discovered spectroscopically by Demarcay in 1896. Symbol, Eu; atomic number 63; at. wt., 151.965 (C=12.011); valence =… …   The Collaborative International Dictionary of English

  • europium — EURÓPIUM s.n. v. europiu. Trimis de LauraGellner, 13.09.2007. Sursa: DN …   Dicționar Român

  • europium — Symbol: Eu Atomic number: 63 Atomic weight: 151.25 Soft silvery metallic element belonging to the lanthanoids. Eu 151 and Eu 153 are the only two stable isotopes, both of which are neutron absorbers. Discovered in 1889 by Sir William Crookes …   Elements of periodic system

  • europium — rare earth element, 1901, named by its discoverer, French chemist Eugène Demarçay (1852 1903) in 1896, from EUROPE (Cf. Europe) + ium …   Etymology dictionary

  • europium — [yo͞o rō′pē əm] n. [ModL: so named (1901) by E. A. Demarçay (1852 1904), Fr chemist < EUROPE + IUM] a chemical element, one of the rare earth elements, used as the red phosphor in color TVs: symbol, Eu; at. no., 63: see the periodic table of… …   English World dictionary

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