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ytterbium(ĭtûr`bēəm) [for Ytterby, a town in Sweden], metallic chemical element; symbol Yb; at. no. 70; at. wt. 173.054; m.p. 819°C;; b.p. about 1,194°C;; sp. gr. about 7.0; valence +2 or +3. Ytterbium is a soft, malleable, ductile, lustrous silver-white metal. Although it is one of the 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. 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. 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. , in some of its chemical and physical properties it more closely resembles calcium, strontium, and barium. It exhibits allotropyallotropy
[Gr.,=other form]. A chemical element is said to exhibit allotropy when it occurs in two or more forms in the same physical state; the forms are called allotropes.
..... Click the link for more information. ; at room temperature a face-centered cubic crystalline form is stable. The metal tarnishes slowly in air and reacts slowly with water but rapidly dissolves in mineral acids. It forms numerous compounds, some of which are yellow or green. The oxide (ytterbia, Yb2O3) is colorless. It is widely distributed in a number of minerals, e.g., gadolinite, and is recovered from monazite but has no commercial uses. Its discovery is credited to J. C. G. de Marignac, who in 1878 separated a substance he called ytterbia. In 1907, Georges Urbain showed that this substance contained lutetium in addition to ytterbium. At about this same time C. A. von Welsbach independently discovered ytterbium and called it aldebaranium.
A rare-earth metal of the yttrium subgroup, symbol Yb, atomic number 70, atomic weight 173.04; lustrous, malleable, soluble in dilute acids and liquid ammonia, reacts slowly with water; melts at 824°C, boils at 1427°C; used in chemical research, lasers, garnet doping, and x-ray tubes.
a soft malleable silvery element of the lanthanide series of metals that occurs in monazite and is used to improve the mechanical properties of steel. Symbol: Yb; atomic no.: 70; atomic wt.: 173.04; valency: 2 or 3; relative density: 6.903 (alpha), 6.966 (beta); melting pt.: 819?C; boiling pt.: 1196?C