Yttrium Facts - Chemical Physical Properties

Yttrium Facts - Chemical Physical Properties Yttrium oxides are a component of the phosphors used to produce the red color in television picture tubes. The oxides have potential use in ceramics and glass. Yttrium oxides have high melting points and impart shock resistance and low expansion to glass. Yttrium iron garnets are used to filter microwaves and as transmitters and transducers of acoustic energy. Yttrium aluminum garnets, with a hardness of 8.5, are used to simulate diamond gemstones. Small quantities of yttrium may be added to reduce the grain size in chromium, molybdenum, zirconium, and titanium, and to increase the strength of aluminum and magnesium alloys. Yttrium is used as a deoxidizer for vanadium and other nonferrous metals. It is used as a catalyst in the polymerization of ethylene. Basic Facts About Yttrium Atomic Number: 39 Symbol: Y Atomic Weight: 88.90585 Discovery: Johann Gadolin 1794 (Finland) Electron Configuration: [Kr] 5s1 4d1 Word Origin: Named for Ytterby, a village in Sweden near Vauxholm. Ytterby is the site of a quarry which yielded many minerals containing rare earths and other elements (erbium, terbium, and ytterbium). Isotopes: Natural yttrium is composed of yttrium-89 only. 19 unstable isotopes are also known. Properties: Yttrium has a metallic silver luster. It is relatively stable in the air except when finely divided. Yttrium turnings will ignite in air if their temperature exceeds 400Â °C. Yttrium Physical Data Element Classification: Transition Metal Density (g/cc): 4.47 Melting Point (K): 1795 Boiling Point (K): 3611 Appearance: silvery, ductile, moderately reactive metal Atomic Radius (pm): 178 Atomic Volume (cc/mol): 19.8 Covalent Radius (pm): 162 Ionic Radius: 89.3 (3e) Specific Heat (20Â °C J/g mol): 0.284 Fusion Heat (kJ/mol): 11.5 Evaporation Heat (kJ/mol): 367 Pauling Negativity Number: 1.22 First Ionizing Energy (kJ/mol): 615.4 Oxidation States: 3 Lattice Structure: hexagonal Lattice Constant (Ã…): 3.650 Lattice C/A Ratio: 1.571 References: Los Alamos National Laboratory (2001), Crescent Chemical Company (2001), Langes Handbook of Chemistry (1952), CRC Handbook of Chemistry Physics (18th Ed.)