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[68] [67] [69] Because of its ductility, tantalum can be drawn into fine wires or filaments, which are used for evaporating metals such as aluminium. Tantalum is inert against most acids except hydrofluoric acid and hot sulfuric acid, and hot alkaline solutions also cause tantalum to corrode. This property makes it a useful metal for chemical ...
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
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.
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.
Tantalum exists in two crystalline phases, alpha and beta. The alpha phase is relatively ductile and soft; it has body-centered cubic structure ( space group Im3m , lattice constant a = 0.33058 nm), Knoop hardness 200–400 HN and electrical resistivity 15–60 μΩ⋅cm.
For Congolese, mining is the readiest source of income, because the work is consistently available, even if only for a dollar a day. [44] The work can be laborious; miners can walk for days into the forest to reach the ore, scratch it from the earth with hand tools, and pan it. About 90% of young men [dubious – discuss] in Congo have done ...
It was just after 3 a.m. in the warm Houston summer of 2019, when first responders arrived at Renard and Patricia Spivey 's home and found 52-year-old Patricia dead in the closet from multiple ...
Columbite minerals are mainly composed of magnesium, iron, niobium, and tantalum where trace amounts of tin, titanium, and scandium have been observed. [19] The overall composition of columbite influences the crystalline structure resulting in different formation processes. Currently, there are two prominent theories for the formation of columbite.