ytterbium

yt·ter·bi·um   (ĭ-tûr'bē-əm)    n.   Symbol Yb A soft, bright, silvery rare-earth element occurring in two allotropic forms and used as an x-ray source for portable irradiation devices, in some laser materials, and in some special alloys. Atomic number 70; atomic weight 173.04; melting point 824°C; boiling point 1,196°C; specific gravity 6.972 or 6.54 (25°C) depending on allotropic form; valence 2, 3. See Table at element. [After Ytterby, a town in Sweden.] yt·ter'bic (-bĭk) adj.

ytterbium 

Main Entry: yt·ter·bi·um
Pronunciation: i-'t&r-bE-&m
Function: noun
: a bivalent or trivalent metallic element of the rare-earthgroup that resembles yttrium and occurs with it and related elements in several minerals —symbol Yb; —see ELEMENT table

ytterbium yt·ter·bi·um (ĭ-tûr'bē-əm)
n.
Symbol Yb
A soft bright allotropic rare-earth element. Atomic number 70; atomic weight 173.04; melting point 824°C; boiling point 1,194°C; specific gravity 6.97 or 6.90 (25°C) depending on allotropic form; valence 2, 3.

ytterbium   (ĭ-tûr'bē-əm)  Pronunciation Key  Symbol Yb A soft, silvery-white metallic element of the lanthanide series that occurs as seven stable isotopes. It is used as a radiation source for portable x-ray machines. Atomic number 70; atomic weight 173.04; melting point 824°C; boiling point 1,196°C; specific gravity 6.972 or 6.54 (25°C) depending on allotropic form; valence 2, 3. See Periodic Table.

ytterbium

((Yb), chemical element, rare-earth metal of the lanthanoid series of the periodic table, a low-melting-point, divalent rare earth with little commercial use.

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