yttric, adj.
/i"tree euhm/, n. Chem.
a rare trivalent metallic element, found in gadolinite and other minerals. Symbol: Y; at. wt.: 88.905; at. no.: 39; sp. gr.: 4.47. Cf. rare-earth element.
[1815-25; < NL, named after Ytterby. See YTTERBIA, -IUM]

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 (Y), chemical element, rare-earth metal of transition Group IIIb of the periodic table, used for red phosphors (phosphor) in colour television. Yttrium metal is silvery in colour, ductile, and relatively reactive; turnings of the metal ignite readily in air.

      Johan Gadolin in 1794 isolated yttria, a new earth or metallic oxide, from a mineral found at Ytterby, Sweden. Yttria, the first rare earth to be discovered, turned out to be a mixture of oxides from which, over a span of more than a century, nine elements, yttrium, scandium (atomic number 21), and the heavy lanthanoid metals from terbium (atomic number 65) to lutetium (atomic number 71), were separated. Yttrium occurs especially in the heavy rare-earth ores, of which gadolinite, euxenite, and xenotime are the most important. In the igneous rocks of the Earth's crust, this element is more plentiful than any of the other rare-earth elements except cerium and is twice as abundant as lead. Yttrium also occurs in the products of nuclear fission. Commercially yttrium is separated from the other rare earths by ion exchange, and the metal is produced by reduction of the fluoride with calcium.

      Yttrium is used in alloys and in metallurgical operations. Yttrium compounds are used in optical glasses and in special ceramics, as catalysts, and in electronic and optical devices including phosphors and lasers. Red phosphors containing yttrium and europium have greatly improved colour television. One phosphor is a europium-activated yttrium orthovanadate; another is a europium-activated yttrium oxide. Garnets utilizing yttrium oxide for solid-state microwave devices are used in radar and communication systems; yttrium–iron garnets, for example, transmit shortwave energy with very little loss. Neodymium-doped yttrium–aluminum garnet lasers provide efficient tools for cutting and welding metals. Radioactive yttrium is employed in cancer therapy.

      Yttrium behaves chemically as a typical rare-earth element having an oxidation state of +3. Its ionic radius is 0.90 angstrom (Å), near the radii of dysprosium and holmium (0.908 Å and 0.894 Å, respectively); separation from these elements is difficult. It forms a series of nearly white salts including the trioxide, the trisulfate, the trichloride, and the tricarbonate. The Y3+ ion is diamagnetic. Stable yttrium-89 is the only naturally occurring isotope.

atomic number
atomic weight
melting point
1,523° C
boiling point
3,337° C
specific gravity
4.457 (25° C)
oxidation state
electronic config.

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Universalium. 2010.

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  • Yttrium — (pronEng|ˈɪtriəm) is a chemical element with symbol Y and atomic number 39. It is a silvery metallic transition metal chemically similar to the lanthanoids and has historically been classified as a rare earth element. Yttrium is almost always… …   Wikipedia

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  • YTTRIUM — De Ytterby, village de Suède. Symbole chimique: Y Numéro atomique: 39 Masse atomique: 88,905 g Point de fusion: 1 523 0C Point d’ébullition: 3 337 0C Densité (à 25 0C): 4,457 Élément chimique du groupe des terres rares, de couleur argentée,… …   Encyclopédie Universelle

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  • Yttrium — Y, Atomgew. 89, seltenes, im Gadolinit vorkommendes Metall. Das Yttriumoxyd Y2O3 ist neben Thoriumoxyd ein wesentlicher Bestandteil mancher Strümpfe für Auersches Gasglühlicht. Moye …   Lexikon der gesamten Technik

  • Yttrium — Yttrĭum (chem. Zeichen Y), seltenes Erdmetall vom Atomgewicht 89, kommt in den nordischen Mineralien Gadolinit, Orthit und Yttrotantalit vor; nach Abscheidung der Oxyde des Cers, Didyms und Lanthans gewinnt man aus den Rückständen die Yttererde …   Kleines Konversations-Lexikon

  • yttrium — Symbol: Y Atomic number: 39 Atomic weight: 88.905 Silvery grey metallic element of group 3 on the periodic table. Found in uranium ores. The only natural isotope is Y 89, there are 14 other artificial isotopes. Chemically resembles the… …   Elements of periodic system

  • yttrium — metallic rare earth element, 1866, coined in Modern Latin by Swedish chemist Carl Gustaf Mosander (1797 1858) from Ytterby, name of a town in Sweden where mineral containing it was found …   Etymology dictionary

  • yttrium — [i′trē əm] n. [ModL < YTTRIA + IUM: name proposed (1822) before isolation of the element by Mosander (see ERBIUM) in 1843] a rare, trivalent, silvery, metallic chemical element found in combination in gadolinite, monazite sand, samarskite, etc …   English World dictionary

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