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The name was based on the wide range of colors found in vanadium compounds. Del Río's lead mineral was ultimately named vanadinite for its vanadium content. In 1867, Henry Enfield Roscoe obtained the pure element. Vanadium occurs naturally in about 65 minerals and fossil fuel deposits. It is produced in China and Russia from steel smelter slag.
The color of chemicals is a physical property of chemicals that in most cases comes from the excitation of electrons due to an absorption of energy performed by the chemical. The study of chemical structure by means of energy absorption and release is generally referred to as spectroscopy .
Vanadium ion is rather large and some complexes achieve coordination numbers greater than 6, as is the case in [V(CN) 7] 4−. Oxovanadium(V) also forms 7 coordinate coordination complexes with tetradentate ligands and peroxides and these complexes are used for oxidative brominations and thioether oxidations.
Structure of vanadyl acetylacetonate Cavansite, a mineral containing the vanadyl cation that illustrates its characteristic color. The vanadyl or oxovanadium(IV) cation, VO 2+, [1] is a functional group that is common in the coordination chemistry of vanadium. Complexes containing this functional group are characteristically blue and paramagnetic.
Vanadium(IV) oxide or vanadium dioxide is an inorganic compound with the formula VO 2. It is a dark blue solid. It is a dark blue solid. Vanadium (IV) dioxide is amphoteric , dissolving in non-oxidising acids to give the blue vanadyl ion , [VO] 2+ and in alkali to give the brown [V 4 O 9 ] 2− ion, or at high pH [VO 4 ] 4− . [ 4 ]
The compound is prepared by the addition of ammonium salts to solutions of vanadate ions, generated by dissolution of V 2 O 5 in basic aqueous solutions, such as hot sodium carbonate. The compound precipitates as a colourless solid. [3] [4] This precipitation step can be slow.
Vanadium(V) oxide serves the crucial purpose of catalysing the mildly exothermic oxidation of sulfur dioxide to sulfur trioxide by air in the contact process: 2 SO 2 + O 2 ⇌ 2 SO 3. The discovery of this simple reaction, for which V 2 O 5 is the most effective catalyst, allowed sulfuric acid to become the cheap commodity chemical it is today.
Flame test of a few metal ions. A flame test involves introducing a sample of the element or compound to a hot, non-luminous flame and observing the color of the flame that results. [4] The compound can be made into a paste with concentrated hydrochloric acid, as metal halides, being volatile, give better results. [5]