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Selenium is a semiconductor and is used in photocells. Applications in electronics, once important, have been mostly replaced with silicon semiconductor devices. Selenium is still used in a few types of DC power surge protectors and one type of fluorescent quantum dot.
The isotope selenium-75 has radiopharmaceutical uses. For example, it is used in high-dose-rate endorectal brachytherapy, as an alternative to iridium-192. [8]In paleobiogeochemistry, the ratio in amount of selenium-82 to selenium-76 (i.e, the value of δ 82/76 Se) can be used to track down the redox conditions on Earth during the Neoproterozoic era in order to gain a deeper understanding of ...
Selenium is a component of the amino acids selenocysteine and selenomethionine. In humans, selenium is a trace element nutrient that functions as cofactor for glutathione peroxidases and certain forms of thioredoxin reductase. [1] Selenium-containing proteins are produced from inorganic selenium via the intermediacy of selenophosphate (PSeO 3 3 ...
Selenium forms two oxides: selenium dioxide (SeO 2) and selenium trioxide (SeO 3). Selenium dioxide is formed by the reaction of elemental selenium with oxygen: [5] + It is a polymeric solid that forms monomeric SeO 2 molecules in the gas phase. It dissolves in water to form selenous acid, H 2 SeO 3.
The chemistry of selenium is largely covalent in nature, noting it can form ionic selenides with highly electropositive metals. The common oxide of selenium (SeO 3) is strongly acidic. Tellurium. Tellurium is a silvery-white, moderately reactive, [8] shiny solid, that has a density of 6.24 g/cm 3 and is soft (MH 2.25) and brittle. It is the ...
Native element minerals are those elements that occur in nature in uncombined form with a distinct mineral structure. The elemental class includes metals, intermetallic compounds, alloys, metalloids, and nonmetals. The Nickel–Strunz classification system also includes the naturally occurring phosphides, silicides, nitrides, carbides, and ...
Selenium (Se) is an element in group 16, the chalcogens. Selenium is the first nonmetal in period 4, with properties similar to sulfur. Selenium is quite rare in pure form in nature, mostly being found in minerals such as pyrite, and even then it is quite rare. Selenium is necessary for humans in trace amounts, but is toxic in larger quantities.
Organoselenium chemistry is the science exploring the properties and reactivity of organoselenium compounds, chemical compounds containing carbon-to-selenium chemical bonds. [1] [2] [3] Selenium belongs with oxygen and sulfur to the group 16 elements or chalcogens, and similarities in chemistry are to be expected. Organoselenium compounds are ...