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Vanadium is a Chemical Element in the Periodic Table that has the symbol '''V''' and Atomic Number 23. A rare, soft and ductile element, vanadium is found combined in certain Mineral s and is used mainly to produce certain Alloy s. It is one of the 26 elements commonly found in living things. NOTABLE CHARACTERISTICS Vanadium is a soft and ductile, gray-white metal. It has good resistance to Corrosion by Alkali s, Sulfuric and Hydrochloric Acid . It Oxidizes readily at about 933 K . Vanadium has good structural strength and a low fission neutron cross section, making it useful in nuclear applications. Although a metal, it shares with Chromium and Manganese the property of having valency oxides with Acid properties. Common Oxidation State s of vanadium include +2, +3, +4 and +5. A popular experiment with ammonium vanadate ( N H 4V O 3), reducing the compound with Zinc metal, can demonstrate colorimetrically all four of these vanadium oxidation states. A +1 oxidation state is also rarely seen. APPLICATIONS Approximately 80% of vanadium produced is used as ferrovanadium or as a Steel additive. Other uses;
HISTORY Vanadium ( Scandinavia n goddess, Vanadis ) was originally Discovered by Andrés Manuel Del Río (a Spanish - Mexican mineralogist) in Mexico City , in 1801 . He called it "brown lead" (now named Vanadinite ). Through experimentation, its colors reminded him of Chromium , so he named the element panchromium. He later renamed this compound erythronium, since most of the salts turned red when heated. The French chemist Hippolyte Victor Collet-Descotils incorrectly declared that del Rio's new element was only impure Chromium . Del Rio thought himself to be mistaken and accepted the statement of the French chemist that was also backed by Del Rio's friend Baron Alexander Von Humboldt In 1831 , Sefström of Sweden rediscovered vanadium in a new oxide he found while working with some Iron ores and later that same year Friedrich Wöhler confirmed del Rio's earlier work. Later, George William Featherstonhaugh , one of the first US geologists, suggested that the element should be named "rionium" after Del Rio, but this never happened. Metallic vanadium was isolated by Henry Enfield Roscoe in 1867 , who reduced Vanadium Chloride (V Cl 3) with Hydrogen . The name vanadium comes from Vanadis , a goddess in Scandinavian Mythology , because the element has beautiful multicolored Chemical Compound s. BIOLOGICAL ROLE In Biology , a vanadium atom is an essential component of some Enzyme s, particularly the vanadium Nitrogenase used by some Nitrogen-fixing microorganisms. Vanadium is essential to Ascidians or Sea Squirt s in Vanadium Chromagen Proteins . The concentration of vanadium in their blood is more than 100 times higher than the concentration of vanadium in the seawater around them. Rat s and Chicken s are also known to require vanadium in very small amounts and deficiencies result in reduced growth and impaired Reproduction . Administration of oxovanadium compounds has been shown to alleviate Diabetes Mellitus symptoms in certain Animal models and Human s. Much like the chromium effect on sugar metabolism, the mechanism of this effect is unknown. OCCURRENCE Vanadium is never found unbound in nature but it does occur in about 65 different Mineral s among which are Patronite (V S 4), Vanadinite Much of the vanadium metal being produced is now made by Calcium reduction of V2O5 in a pressure vessel. Vanadium is usually recovered as a by-product or co-product, and so world resources of the element are not really indicative of available supply. ''See also .'' ISOLATION Vanadium is available commercially and production of a sample in the Laboratory is not normally required. Commercially, routes leading to metallic vanadium as main product are not usually required as enough is produced as Byproduct in other processes. In industry, heating of vanadium ore or residues from other processes with Salt , NaCl, or Sodium Carbonate , Na2CO3, at about 850°C gives sodium vanadate, NaVO3. This is dissolved in water and acidified to give a red solid which in turn is melted to form a crude form of Vanadium Pentoxide , "V2O5". Reduction of vanadium pentoxide with Calcium , Ca, gives pure vanadium. An alternative suitable for small scales is the reduction of vanadium pentachloride, VCl5, with Hydrogen , H2, or Magnesium , Mg. Many other methods are also in use. Industrially, most vanadium is used as an additive to improve Steel s. Rather than proceed via pure vanadium metal it is often sufficient to react the crude of vanadium pentoxide, "V2O5", with crude Iron . This produces ferrovanadium suitable for further work. COMPOUNDS Vanadium Pentoxide (V2O5) is used as a catalyst, dye and color-fixer. It is extremely toxic if inhaled, and dangerous for the environment. Vanadyl Sulfate (VOSO4), also called vanadium(IV) sulfate oxide hydrate, is used as a relatively controversial Dietary Supplement , primarily for increasing Insulin levels and Body-building . Whether it works for the latter purpose has not been proven, and there is some evidence that athletes who take it are merely experiencing a Placebo Effect . It is toxic in high doses.
ISOTOPES Naturally occurring vanadium is composed of 1 stable Isotope 51V and one radioactive isotope 50V with a Half-life of 1.5×1017 years. 24 artificial Radioisotope s have been characterized (in the range of Mass Number between 40 and 65) with the most stable being 49V with a half-life of 330 days, and 48V with a half-life of 15.9735 days. All of the remaining Radioactive isotopes have half-lives that are less than 1 hour and the majority of these have half lives that are less than 10 seconds. In 4 isotopes, Metastable Excited States were found (including 2 metastable states for 60V). The primary Decay Mode before the most abundant stable isotope, 51V, is Electron Capture and the primary mode after is Beta Decay . The primary Decay Product s before 51V are element 22 ( Titanium ) isotopes and the primary products after are element 24 ( Chromium ) isotopes. PRECAUTIONS Powdered metallic vanadium is a fire hazard, and unless known otherwise, all vanadium compounds should be considered highly toxic. Generally, the higher the oxidation state of vanadium, the more toxic the compound is. The most dangerous one is Vanadium Pentoxide . The Occupational Safety And Health Administration (OSHA) has set an exposure limit of 0.05 mg/m3 for vanadium pentoxide dust and 0.1 mg/m3 for vanadium pentoxide fumes in workplace air for an 8-hour workday, 40-hour work week. The National Institute For Occupational Safety And Health (NIOSH) has recommended that 35 mg/m3 of vanadium be considered immediately dangerous to life and health. This is the exposure level of a chemical that is likely to cause permanent health problems or death. SEE ALSO REFERENCES EXTERNAL LINKS
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