Vanadium
. Vanadium, symbol V, silver-white metallic element with an atomic number of 23. Vanadium is one of the transition elements of the periodic table . It was discovered in 1801 in Mexico by Andrés Manuel del Rio, but it was mistaken for a form of chromium . Vanadium was rediscovered in about 1830 by the Swedish chemist Nils Gabriel Sefström. PROPERTIES AND OCCURRENCE Vanadium takes a high polish and is one of the hardest of all metals. It melts at about 1890° C (about 3434° F), boils at about 3380° C (about 6116° F), and has a specific gravity of 5.96. The atomic weight of vanadium is 50.941. Vanadium is soluble in nitric and sulfuric acids and insoluble in hydrochloric acid, dilute sodium hydroxide, and dilute alcohol. Vanadium forms several acidic oxides, the most important of which are the dark green trioxide and the orange pentoxide. Other important compounds include vanadium monosulfide, vanadium trisulfide, vanadium dichloride, vanadium trichloride, vanadium dihydroxide, and metava...