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Tantalum is a chemical element; it has symbol Ta and atomic number 73. Previously known as tantalium, [citation needed] it is named after Tantalus, a figure in Greek mythology. [11] Tantalum is a very hard, ductile, lustrous, blue-gray transition metal that is highly corrosion-resistant.
Tantalum ores often contain significant amounts of niobium, which is itself a valuable metal.As such, both metals are extracted so that they may be sold. The overall process is one of hydrometallurgy and begins with a leaching step; in which the ore is treated with hydrofluoric acid and sulfuric acid to produce water-soluble hydrogen fluorides, such as the heptafluorotantalate.
As with other metals with low atomic numbers, a variety of reduced halide cluster ions is known, the prime example being [Nb 6 Cl 18] 4−. [31] Tantalum halides span the oxidation states of +5, +4, and +3. Tantalum pentafluoride (TaF 5) is a white solid with a melting point of 97.0 °C. The anion [TaF 7] 2-is used for its separation from ...
Tantalum(V) chloride, also known as tantalum pentachloride, is an inorganic compound with the formula TaCl 5. It takes the form of a white powder and is commonly used as a starting material in tantalum chemistry.
The synthesis of tantalocene trihydride was first reported by Green, McCleverty, Pratt, and Wilkinson in 1961. [1] Tantalum pentachloride was added to a solution of sodium cyclopentadienide in tetrahydrofuran and an excess of sodium borohydride with yields reaching 60%, although the authors report that the preparation does not always succeed.
The mineral group tantalite [(Fe, Mn)Ta 2 O 6] is the primary source of the chemical element tantalum, a corrosion (heat and acid) resistant metal.It is chemically similar to columbite, and the two are often grouped together as a semi-singular mineral called coltan or "columbite-tantalite" in many mineral guides.
Natural tantalum (73 Ta) consists of two stable isotopes: 181 Ta (99.988%) and 180m Ta (0.012%). There are also 35 known artificial radioisotopes, the longest-lived of which are 179 Ta with a half-life of 1.82 years, 182 Ta with a half-life of 114.43 days, 183 Ta with a half-life of 5.1 days, and 177 Ta with a half-life of 56.56 hours.
A toxic heavy metal is a common but misleading term for a metal-like element noted for its potential toxicity. [4] Not all heavy metals are toxic and some toxic metals are not heavy. [ 5 ] Elements often discussed as toxic include cadmium , mercury and lead , [ 6 ] all of which appear in the World Health Organization 's list of 10 chemicals of ...