The elements contained in Group 5 of the periodic table (prepared according to IUPAC ) are:
vanadium (23)
niobium (41)
tantalum (73)
dubnium (105)
These elements are classed in Group 5 because their 5 electrons in the valence shell. Dubnium not exist in nature.
Vanadium Vanadium is the ' chemical element of atomic number 23. Its symbol is V. It is a rare element, soft and ductile, which is in the form of a compound in certain minerals. It is mainly used in metallurgy for the production of alloys.
Features: V is present in abundance of 0.0136% (136ppm) that is the 5th most abundant element among the later transition elements Fe, Ti, Mn and Zr
Vanadium is a bright white metal, soft and ductile. It has good resistance to corrosion by alkali , 's sulfuric acid and ' s hydrochloric acid. Exposed to ' air you oxidizes rapidly at temperatures above 933 K (660 ° C).
Vanadium has a good consistency and a small cross section with neutrons from nuclear fission , making it suitable for use in applications related to nuclear energy production . Chemically
shows an intermediate response between metal and non-metal both acid that basic . The
oxidation states most frequently assumed by the vanadium compounds are +2, +3, +4 and +5. In a laboratory experiment can be observed colorimetrically by the passage of these vanadium oxidation states during the reduction of ammonium vanadate with NH4VO3 zinc metal.
In rare cases, the vanadium oxidation may also take the number of +1.
Niobium Niobium, also formerly known by the name of Columbia because the discovered together tantalum in the mineral columbite , is the ' chemical element of atomic number 41. Its symbol is Nb. It is a transition metal rare, soft, ductile, gray. Is extracted from niobate and is mainly used in the production of special alloys and high strength welds.
Features: Niobium is a shiny gray ductile metal that takes on a bluish tinge when left exposed to air at room temperature for prolonged periods. The chemical properties of niobium are similar to those of tantalum, which belongs to the same group of the periodic table of the elements, this similarity in the reactivity of Nb and Ta is due to the fact that their dimensions are almost identical, strange thing can be explained by the lanthanide contraction .
Even at high temperatures, is processed in an inert atmosphere, since already at 200 ° C tends to undergo oxidation . His
oxidation states most common are +2, +3 and +5.
Tantalum Tantalum is the ' chemical element of atomic number 73. Its symbol is Ta.
is a transition metal hard and malleable, shiny, blue-gray, very resistant to corrosion, especially the attack of acids , and is a good conductor of heat and electricity. It is rather rare in nature and is found in mineral tantalite . Tantalum is used in surgical instruments and installations intracorporeal implants, because they do not react with body fluids.
Features: As already stated, tantalum is highly resistant to corrosion, in practice, at temperatures below 150 ° C , it can be considered completely immune to chemical attack, even at extremely aggressive substances as the ' aqua regia, and can be affected only by' hydrofluoric acid, from acid solutions containing fluoride ion and sulfur trioxide free. Tantalum has a very high melting point, surpassed only by tungsten and rhenium (3290 K melting point, boiling point 5731 K). Tantalum has the highest electrical capacity specific than any other substance.
Dubnium
Dubnium 's chemical element in the periodic table of elements, that has the symbol Db and atomic number as 105.
is a synthetic element, highly radioactive isotope which has a more stable half-life of less than 40 seconds. This element therefore has no practical applications and its properties are poorly understood.
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