URANIUM

(Lat.), n. n. U2r(ur)-an(asn)'i2-usm(u4m). Fr., u. Ger., Uran. A metallic element discovered by Klaproth in 1789, eight years after the discovery of the planet Uranus, from which it was named. It occurs in nature usually as an oxide. It is a hard, malleable, grayish-white metal of silvery lustre. In composition it acts as a tetrad, pentad, or hexad. Symbol, U; sp. gr., 18'33; atomic weight, 240. [B, 3.] U. tetroxide. A body, UOi, forming either a colorle micro-crystalline powder, or. combined with water of crystallization, UO4 + 2H,O, a yellowish-white substance. [B.] U. trioxide. A brownish-yellow powder, UO3 = (UO2)' O. [B, 3.] [s. 675]