89.0 Y; atomic

weight

See also:

• 89.0 Y; atomic weight YTTRIUM [symbol (0 =16)]

YTTRIUM [

See also:

• SYMBOL (Gr. o-uµ(3oXov, a sign)

symbol (0 =16)]  , a metallic chemical element . In its character yttrium is closely allied to, and in nature is always associated with, cerium, lanthanum, didymium and erbium (see RARE EARTHS) . For the preparation of yttrium compounds the best raw material is gadolinite, which, according to Konig, consists of 22.61% of silica, 34.64 of yttria, Y203, and 42.75 of the oxides of erbium, cerium, didymium, lanthanum, iron, beryllium, calcium, magnesium and sodium . The extraction (as is the case with all the rare earths) is a matter of great difficulty . Metallic yttrium is obtainable as a dark grey powder by reducing the chloride with potassium, or by electrolysing the double chloride of yttrium and sodium . It decomposes water slowly in the cold, and more rapidly on heating . Yttria, Y203, is a yellowish white powder, which at high temperatures radiates out a most brilliant white light . It is soluble, slowly but completely, in mineral acids . It is recognized by its very characteristic spark spectrum . Solutions of yttria salts in their behaviour to reagents are not unlike those of zirconia . The atomic weight was determined by Cleve .