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Jai Ganesh

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Yttrium

Yttrium

Gist

Yttrium (Y) is a chemical element, a silvery-metallic transition metal, and is often classified as a rare earth element. It has an atomic number of 39 and is found in Group 3 of the periodic table. Yttrium is known for its diverse applications, ranging from electronics and medicine to high-tech industries.

Yttrium is a versatile element primarily used in phosphors for displays and lighting, alloys, and certain medical applications. It's also found in ceramics, electronics, lasers, and even some cancer treatments.

Summary

Yttrium is a chemical element; it has symbol Y and atomic number 39. It is a silvery-metallic transition metal chemically similar to the lanthanides and has often been classified as a "rare-earth element". Yttrium is almost always found in combination with lanthanide elements in rare-earth minerals and is never found in nature as a free element. 89Y is the only stable isotope and the only isotope found in the Earth's crust.

The most important present-day use of yttrium is as a component of phosphors, especially those used in LEDs. Historically, it was once widely used in the red phosphors in television set cathode ray tube displays. Yttrium is also used in the production of electrodes, electrolytes, electronic filters, lasers, superconductors, various medical applications, and tracing various materials to enhance their properties.

Yttrium has no known biological role. Exposure to yttrium compounds can cause lung disease in humans.

Details

Yttrium (Y) is a chemical element, a rare-earth metal of Group 3 of the periodic table.

Yttrium is a silvery white, moderately soft, ductile metal. It is quite stable in air; rapid oxidation begins above approximately 450 °C (840 °F), resulting in Y2O3. The metal readily reacts with diluted acids—except hydrofluoric acid (HF), in which the insoluble protective layer of YF3 that forms on the surface of the metal prevents further reaction. Yttrium turnings ignite readily in air, burning white-hot. The metal is paramagnetic with a temperature-independent magnetic susceptibility between 10 and 300 K (−263 and 27 °C, or −442 and 80 °F). It becomes superconducting at 1.3 K (−271.9 °C, or −457 °F) at pressures exceeding 110 kilobars.

In 1794 Finnish chemist Johan Gadolin 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 lanthanide metals from terbium (atomic number 65) to lutetium (atomic number 71)—were separated. Yttrium occurs especially in the heavy rare-earth ores, of which laterite clays, gadolinite, euxenite, and xenotime are the most important. In the igneous rocks of 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 products of nuclear fission.

Stable yttrium-89 is the only naturally occurring isotope. A total of 33 (excluding nuclear isomers) radioactive isotopes of yttrium ranging in mass from 77 to 109 and half-life from 41 milliseconds (yttrium-108) to 106.63 days (yttrium-88) have been reported.

Commercially, yttrium is separated from the other rare earths by liquid-liquid or ion-exchange extraction, and the metal is produced by metallothermic reduction of the anhydrous fluoride with calcium. Yttrium exists in two allotropic (structural) forms. The α-phase is close-packed hexagonal with a = 3.6482 Å and c = 5.7318 Å at room temperature. The β-phase is body-centered cubic with a = 4.10 Å at 1,478 °C (2,692 °F).

Yttrium and its compounds have numerous uses. Major applications include hosts for red phosphors for fluorescent lamps, colour displays, and TV screens that use cathode-ray tubes. Yttrium aluminum garnet (YAG) doped with other rare earths is used in lasers; yttrium iron garnet (YIG) is used for microwave filters, radars, communications, and synthetic gems; and yttrium oxide-stabilized cubic zirconia is used in oxygen sensors, structural ceramics, thermal barrier coatings, and synthetic diamonds. A major use of yttrium is in high-temperature superconducting ceramics, such as YBa2Cu3O7, which has a superconducting transition temperature of 93 K (−180 °C, or −292 °F) for electrical power transmission lines and superconducting magnets. The metal is used as an alloying addition to ferrous and nonferrous alloys for improved corrosion resistance and oxidation resistance. Yttrium compounds are used in optical glasses and as catalysts.

Yttrium behaves chemically as a typical rare-earth element having an oxidation state of +3. Its ionic radius is near the radii of dysprosium and holmium, making separation from those elements difficult. Besides the white sesquioxide, yttrium forms a series of nearly white salts including the sulfate, the trichloride, and the carbonate.

Element Properties

atomic number  :  39
atomic weight  :  88.90585
melting point  :  1,522 °C (2,772 °F)
boiling point  :  3,345 °C (6,053 °F)
specific gravity  :  4.469 (24 °C, or 75 °F)
oxidation state  :  +3.

Additional Information:

Appearance

A soft, silvery metal.

Uses

Yttrium is often used as an additive in alloys. It increases the strength of aluminium and magnesium alloys. It is also used in the making of microwave filters for radar and has been used as a catalyst in ethene polymerisation.

Yttrium-aluminium garnet (YAG) is used in lasers that can cut through metals. It is also used in white LED lights.

Yttrium oxide is added to the glass used to make camera lenses to make them heat and shock resistant. It is also used to make superconductors. Yttrium oxysulfide used to be widely used to produce red phosphors for old-style colour television tubes.

The radioactive isotope yttrium-90 has medical uses. It can be used to treat some cancers, such as liver cancer.

Biological role

Yttrium has no known biological role. Its soluble salts are mildly toxic.

Natural abundance

Xenotime can contain up to 50% yttrium phosphate. It is mined in China and Malaysia. Yttrium also occurs in the other ‘rare earth’ minerals, monazite and bastnaesite. Yttrium metal is produced by reducing yttrium fluoride with calcium metal.

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