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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.
A typical human contains 21 parts per billion of niobium. Niobium is in the minerals columbite and pyrochlore. [19] 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.
Metal toxicity or metal poisoning is the toxic effect of certain metals in certain forms and doses on life.Some metals are toxic when they form poisonous soluble compounds. . Certain metals have no biological role, i.e. are not essential minerals, or are toxic when in a certain for
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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.
In humans, heavy metal poisoning is generally treated by the administration of chelating agents. [71] These are chemical compounds, such as CaNa 2 EDTA (calcium disodium ethylenediaminetetraacetate) that convert heavy metals to chemically inert forms that can be excreted without further interaction with the body.
A new color-coded heat warning system relies on magenta to alert Americans to the most dangerous conditions they may see this summer. The National Weather Service and the Centers for Disease ...
The rare-earth elements (REE), also called the rare-earth metals or rare earths, and sometimes the lanthanides or lanthanoids (although scandium and yttrium, which do not belong to this series, are usually included as rare earths), [1] are a set of 17 nearly indistinguishable lustrous silvery-white soft heavy metals. Compounds containing rare ...