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Tantalum pentoxide (Ta 2 O 5) is the most important compound from the perspective of applications. Oxides of tantalum in lower oxidation states are numerous, including many defect structures, and are lightly studied or poorly characterized. [38]
There are 2 parts per million of tantalum in the Earth's crust, making it the 51st most abundant element there. Soil contains on average 1 to 2 parts per billion of tantalum, and seawater contains 2 parts per trillion of tantalum. A typical human contains 2.9 parts per billion of tantalum. Tantalum is found in the minerals tantalite and ...
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.
The river water was contaminated with toxic metals including arsenic, copper, barium, cadmium, chromium, lead, mercury, nickel, and thallium. [2] Cleanup costs may exceed $1.2 billion. [3] A toxic heavy metal is a common but misleading term for a metal-like element noted for its potential toxicity. [4]
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.
Vehicles carrying dangerous goods must be equipped with orange signs, where the upper code number identifies the type of hazard, and the lower code number identifies the specific substance. These symbols cannot be readily interpreted without the aid of a table to translate the numerical codes.
A commercially important example is heptafluorotantalate (TaF 7 2−) and its potassium salt (K 2 TaF 7). Potassium heptafluorotantalate. Many oxides of tantalum are called tantalates. They are viewed as derivatives of "tantalic acid", hypothetic compounds with the formulas Ta 2 O 5 ·nH 2 O [1] or HTaO 3 [2]).