Yttrium - chemistry.

Yttrium - chemistry. Yttrium, symbol Y, silver-white metallic element with an atomic number of 39. Yttrium is one of the transition elements of the periodic table (see Periodic Law). The elements yttrium, ytterbium, terbium, and erbium were all named for the town of Ytterby in Sweden, the location of a quarry that yielded several rare earth elements. Yttrium was isolated by the Swedish chemist Carl Gustav Mosander in 1843. Yttrium metal can be prepared by the reduction of yttrium triflouride (YF3) with calcium. It oxidizes readily in air to the oxide Y2O 3 and dissolves in hot water to form the hydroxide Y(OH)3. Yttrium ranks about 29th in abundance of the elements in Earth's crust. Yttrium is found as an oxide in rare earth minerals such as monazite and bastnasite. It is used extensively in phosphors employed in color television tubes. Yttrium melts at about 1522°C (about 2772°F), boils at about 3345°C (about 6053°F), and has a specific gravity of 4.47. The atomic weight of yttrium is 88.906. Yttrium is sometimes included among the rare earth elements. Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.