Chromium

(krō'me-nт.) [Gr. chromo;-so called because its compounds are remarkable for their numerous and brilliant colors.) (Chem.) A metallic element discovered by Vauquelin in 1797. It is almost unknown in the metallic state. Its most abundant native compound is chrome iron-ore, a combination of oxides of iron and chromium, found in the U. States, in Sweden, and in Ru ia. The at. weight of C. is 26-2; its symbol Cr. It forms several oxides: the prot oxide (Cro), the sesquioxide (CrO3), chromic acid (CrO3), and the per chromic acid (Cr207). Chromic acid, the most important of these, forms fine crimson needles, which are deliquescent. It forms salts with bases. See CHROMATES. Chromo-lithography. See LITHOGRAPHY. Chromo-photography. See PHOTOGRAPHY. [s. 185]