dysprosium(redirected from Element 66)
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Related to Element 66: Element 56, Element 69, Element 68, Element 67, Element 89, Element 77, Element 99
dysprosium(dĭsprō`zēəm) [Gr.,=hard to get at], metallic chemical element; symbol Dy; at. no. 66; at. wt. 162.500; m.p. 1,412°C;; b.p. 2,562°C;; sp. gr. 8.54 at 25°C;; valence+3. Dysprosium is a lustrous silvery metal; it is very soft and can be cut with a knife. It is in Group 3 of the periodic tableperiodic table,
chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley. In the periodic table the elements are arranged in columns and rows according to increasing atomic number (see the table entitled
..... Click the link for more information. and is a member of the lanthanide serieslanthanide series,
a series of metallic elements, included in the rare-earth metals, in Group 3 of the periodic table. Members of the series are often called lanthanides, although lanthanum (atomic number 57) is not always considered a member of the series.
..... Click the link for more information. ; all members of this series are rare-earth metalsrare-earth metals,
in chemistry, group of metals including those of the lanthanide series and actinide series and usually yttrium, sometimes scandium and thorium, and rarely zirconium. Promethium, which is not found in nature, is not usually considered a rare-earth metal.
..... Click the link for more information. and resemble one another in their chemical properties. Dysprosium is stable in air at room temperature. It dissolves in both dilute and concentrated mineral acids; forms a white oxide known as dysprosia; and, with other elements, forms several brightly colored salts. It is commonly found with other rare-earth metals in several minerals, including gadolinite and euxenite. Dysprosium and its compounds are among the most highly susceptible to magnetization of all substances and are used in special magnetic alloys. A cermet of dysprosium oxide and nickel is used in nuclear reactor control rods. Dysprosium is used with argon in mercury-vapor lamps to give a higher light output and balance the color spectrum. Although dysprosium was discovered (but not isolated) in 1886 by P. E. Lecoq de Boisbaudran, a French chemist, it did not become available in relatively pure form until the 1950s.
A metallic rare-earth element, symbol Dy, atomic number 66, atomic weight 162.50.
a soft silvery-white metallic element of the lanthanide series: used in laser materials and as a neutron absorber in nuclear control rods. Symbol: Dy; atomic no.: 66; atomic wt.: 162.50; valency: 3; relative density: 8.551; melting pt.: 1412?C; boiling pt.: 2567?C