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Tantalum was discovered in Sweden in 1802 by Anders Ekeberg, in two mineral samples – one from Sweden and the other from Finland. [15] [16] One year earlier, Charles Hatchett had discovered columbium (now niobium). [17] In 1809, the English chemist William Hyde Wollaston compared the oxides of columbium and tantalum, columbite and tantalite.
The CompTox Chemicals Dashboard is a freely accessible online database created and maintained by the U.S. Environmental Protection Agency (EPA). The database provides access to multiple types of data including physicochemical properties, environmental fate and transport, exposure, usage, in vivo toxicity, and in vitro bioassay.
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 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.
Coltan is the colloquial name for the mineral columbite-tantalum ("col-tan"). In the early 21st century coltan mining is associated with human rights violations such as child labour, systematic exploitation of the population by governments or militant groups, exposure to toxic chemicals and other hazards as a result of lax environmental protection, and general safety laws and regulations. [1]
macOS Sequoia (version 15) is the twenty-first and current major release of Apple's macOS operating system, the successor to macOS Sonoma. It was announced at WWDC 2024 on June 10, 2024. [ 4 ] In line with Apple's practice of naming macOS releases after landmarks in California , it is named after Sequoia National Park , located in the Sierra ...
Pentakis(dimethylamido)tantalum is an organometallic compound of tantalum. It is a colorless solid that is soluble in organic solvents . It hydrolyzes readily to release dimethylamine .