Selenium compounds commonly exist in the oxidation states −2, +2, +4, and +6. At levels of 1 mg/m3, selenium is immediately dangerous to life and health. However, NIST makes no warranties to that effect, and NIST The selenocysteine-containing form occurs in species as diverse as green algae, diatoms, sea urchins, fish, and chickens. Se2. 2) What noble gas is isoelectronic with this ion. Selenium compounds commonly exist in the oxidation states −2, +2, +4, and +6. [7] It resists oxidation by air and is not attacked by nonoxidizing acids. [25] Both chemists owned a chemistry plant near Gripsholm, Sweden, producing sulfuric acid by the lead chamber process. Synonyms. selenium(2-) 22541-48-6. selanediide. In solution it ionizes to HSe−. Database and to verify that the data contained therein have [all data], Go To: Top, Gas phase ion energetics data, References. Other selenium allotropes may contain Se6 or Se7 rings. a. Se^-2, selenide ion b. Ba^+2 + 2e^-, barium ion c. P^-3, phosphide ion d. I^-, iodide ion. ... An ionic molecule with a formula of CsO_2 is possible. [117] Hydrogen selenide is an extremely toxic, corrosive gas. selenium, vanadium, magnesium, copper, and zinc, may have been lacking in some terrestrial mineral-deficient areas. Another selenium-bearing enzyme in some plants and in animals (thioredoxin reductase) generates reduced thioredoxin, a dithiol that serves as an electron source for peroxidases and also the important reducing enzyme ribonucleotide reductase that makes DNA precursors from RNA precursors. you should know periodic table, Selenium on 6A grup. Ions, Formula Previous Answers Request Answer Submit Part C Sodium And Phosphorus Express Your Answers As Ions And Chemical Formula Separated By A Commas. These include silver selenite (Ag2SeO3) and sodium selenite (Na2SeO3). See more Selenium products. In low doses, selenium has shown a beneficial effect on plant resistance to various environmental stress factors including drought, UV-B, soil salinity, and cold or hot temperatures. 7789-65-3. Five of these, 74Se, 76Se, 77Se, 78Se, 80Se, are stable, with 80Se being the most abundant (49.6% natural abundance). The regulation of lead in drinking water applications such as in the US with the Safe Drinking Water Act of 1974, made a reduction of lead in brass necessary. Synonyms. Selenium (atomic symbol: Se, atomic number: 34) is a Block P, Group 16, Period 4 element with an atomic radius of 78.96. selenide(2-) Selenium, ion (Se2+) SE-2. I was thinking Bromine since again it is closest to Krypton. It is involved as a catalyst in several important enzymes. The selenium cell was used in the photophone developed by Alexander Graham Bell in 1879. The recoding mechanism was worked out first in bacteria and then in mammals (see SECIS element).[40]. Especially common are selenides (R2Se, analogues of thioethers), diselenides (R2Se2, analogues of disulfides), and selenols (RSeH, analogues of thiols). Se(2-) A816696. [12] Isotopes lighter than the stable isotopes primarily undergo beta plus decay to isotopes of arsenic, and isotopes heavier than the stable isotopes undergo beta minus decay to isotopes of bromine, with some minor neutron emission branches in the heaviest known isotopes. Cancer patients receiving daily oral doses of selenothionine may achieve very high plasma and urine selenium concentrations. From about 500 million years ago, freshwater and terrestrial plants slowly optimized the production of "new" endogenous antioxidants such as ascorbic acid (vitamin C), polyphenols (including flavonoids), tocopherols, etc. In solution it is a diprotic acid: H 2 SeO 3 ⇌ H + + HSeO − 3 (pK a = 2.62) HSeO − 3 ⇌ H + + SeO 2− 3 (pK a = 8.32) Electron affinity of selenium measured by photodetachment microscopy, The price was relatively stable during 2004–2010 at about US$30 per pound (in 100 pound lots) but increased to $65/lb in 2011. ___ ? It dissolves in water to form selenous acid, H2SeO3. China is the dominant consumer of selenium at 1,500–2,000 tonnes/year. High doses of Se supplements in pregnant animals might disturb the Zn:Cu ratio and lead to Zn reduction; in such treatment cases, Zn levels should be monitored. Respiratory capacity is further reduced due to selenium binding to hemoglobin. Copyright for NIST Standard Reference Data is governed by (i) Selenium forms an ionic compound with potassium. The consumption in 2010 was divided as follows: metallurgy – 30%, glass manufacturing – 30%, agriculture – 10%, chemicals and pigments – 10%, and electronics – 10%. [75][76][77], 75Se is used as a gamma source in industrial radiography.[78]. Selenium occurs naturally in a number of inorganic forms, including selenide, selenate, and selenite, but these minerals are rare. For the software testing framework, see. [23], Selenium reacts with cyanides to yield selenocyanates:[6], Selenium, especially in the II oxidation state, forms stable bonds to carbon, which are structurally analogous to the corresponding organosulfur compounds. This smell was not typical of arsenic, but a similar odor was known from tellurium compounds. Some of the selenium oxyhalides, such as selenium oxyfluoride (SeOF2) and selenium oxychloride (SeOCl2) have been used as specialty solvents. In general, absorption of dietary selenium is lower in ruminants than other animals, and is lower from forages than from grain. It rarely occurs in its elemental state or as pure ore compounds in the Earth's crust. Formula: Se-Molecular weight: 78.96; Information on this page: Gas phase ion energetics data; References; Notes; Other data available: Reaction … [74], Selenium is used in the toning of photographic prints, and it is sold as a toner by numerous photographic manufacturers. [88], Increased dietary selenium reduces the effects of mercury toxicity,[89][90][91] although it is effective only at low to modest doses of mercury. [65] These detectors use amorphous selenium to capture and convert incident x-ray photons directly into electric charge.[66]. [48], Selenium is most commonly produced from selenide in many sulfide ores, such as those of copper, nickel, or lead. Use o to represent an electron from an atom of potassium. Three days later, a pharmacy released a statement explaining that the horses had received an incorrect dose of one of the ingredients used in a vitamin/mineral supplement compound that had been incorrectly prepared by a compounding pharmacy. selenium (4+) Selenium, ion (4+) 22541-55-5. Also naturally occurring is the long-lived primordial radionuclide 82Se, with a half-life of 9.2×1019 years. What is the formula for the ionic compound formed by calcium ions and nitrate ions? It has an approximate composition of SeS2, with individual rings varying in composition, such as Se4S4 and Se2S6. Selenium is an essential nutrient that exhibits potent anticarcinogenic properties, and deficiency of selenium may cause certain neurologic diseases. As a crystalline solid, the compound can be seen as pyramidal molecules that are interconnected with hydrogen bonds. See more Selenium products. The packing is most dense in the α form. [55] Its photovoltaic and photoconductive properties are still useful in photocopying,[67][68][69][70] photocells, light meters and solar cells. In Belews Lake North Carolina, 19 species of fish were eliminated from the lake due to 150-200 μg Se/L wastewater discharged from 1974 to 1986 from a Duke Energy coal-fired power plant. Selenium poisoning can be passed from parents to offspring through the egg, and selenium poisoning may persist for many generations. Selenium was later confirmed to be the toxic factor. Data compilation copyright Formula Weight. Although trace amounts of selenium are necessary for cellular function in many animals, including humans, both elemental selenium and (especially) selenium salts are toxic in even small doses, causing selenosis. [128], Selenium deficiency can occur in patients with severely compromised intestinal function, those undergoing total parenteral nutrition, and[129] in those of advanced age (over 90). The effects of selenium in preventing cancer and neurologic diseases may be mediated by selenium-binding proteins, and decreased expression of this gene may be associated with several types of cancer. diselenium. [109], Certain species of plants are considered indicators of high selenium content of the soil because they require high levels of selenium to thrive. [134], In the regions (e.g. (Only the deiodinase iodotyrosine deiodinase, which works on the last breakdown products of thyroid hormone, does not use selenium. In soils, selenium most often occurs in soluble forms such as selenate (analogous to sulfate), which are leached into rivers very easily by runoff. Selenides are reducing agents when pure. Phys. Upon heating, it softens at 50 °C and converts to gray selenium at 180 °C; the transformation temperature is reduced by presence of halogens and amines. They are highly soluble in aqueous solutions at ambient temperatures. Find Similar Structures. [116] Elemental selenium and most metallic selenides have relatively low toxicities because of low bioavailability. [15], Selenium trioxide may be synthesized by dehydrating selenic acid, H2SeO4, which is itself produced by the oxidation of selenium dioxide with hydrogen peroxide:[17], Hot, concentrated selenic acid can react with gold to form gold(III) selenate.[18]. [28][29] This led to its use as a cell for sensing light. With highly electropositive metals, such as aluminium, these selenides are prone to hydrolysis:[6]. Extreme cases of selenosis can exhibit cirrhosis of the liver, pulmonary edema, or death. Illustrative selenides include mercury selenide (HgSe), lead selenide (PbSe), zinc selenide (ZnSe), and copper indium gallium diselenide (Cu(Ga,In)Se2). Eidon Ionic Minerals Liquid Selenium. been selected on the basis of sound scientific judgment. ions, formula = These findings suggest that, with the exception of vertebrates, aquatic life supports selenium use, whereas terrestrial habitats lead to reduced use of this trace element. 1. name the ions formed by the following elements a. selenium b. barium c. phosphorus d. iodine. In humans, selenium is a trace element nutrient that functions as cofactor for reduction of antioxidant enzymes, such as glutathione peroxidases[86] and certain forms of thioredoxin reductase found in animals and some plants (this enzyme occurs in all living organisms, but not all forms of it in plants require selenium). [83] It has also been suggested that season could have an impact on the harmful effects of selenium on fish. [84] To help reduce the amount of selenium entering our oceans, policies can be put into place such as using microbes or enzymes that target and break down metalloids like selenium. [clarification needed]. [95][96] It seems as though when mercury levels in a marine fish rise, so do the selenium levels. This hydrolysis occurs because of the extreme basicity of the Se 2− ion. 22788-28-9 Part B rubidium and selenium Express your answers as ions and chemical formula separated by a commas. Further studies are needed to confirm these interactions. [52], Industrial production of selenium usually involves the extraction of selenium dioxide from residues obtained during the purification of copper. For other applications, a red color may be desired, produced by mixtures of CdSe and CdS. Structure. Fish affected by selenium may experience swelling of the gill lamellae, which impedes oxygen diffusion across the gills and blood flow within the gills. However, most elemental selenium comes as a byproduct of refining copper or producing sulfuric acid. [97], From about three billion years ago, prokaryotic selenoprotein families drive the evolution of selenocysteine, an amino acid. [111], Although selenium is an essential trace element, it is toxic if taken in excess. [56], During the electrowinning of manganese, the addition of selenium dioxide decreases the power necessary to operate the electrolysis cells. © 2018 by the U.S. Secretary of Commerce The subscripts for the base formula can be determined using either of the methods described above. [71] Cadmium selenide was an important component in quantum dots. The high bioaccumulation of selenium in aquatic environments cause large fish kills depending on the species in the affected area. Selenium forms two oxides: selenium dioxide (SeO2) and selenium trioxide (SeO3). Further concentration through bioaccumulation occurs along the food chain, as predators consume selenium rich prey. With strong reducing agents, it forms polyselenides. selenide ion. 8O54YXR180. It is a strongly odiferous, toxic, and colorless gas. Selenium dioxide is formed by the reaction of elemental selenium with oxygen:[6], It is a polymeric solid that forms monomeric SeO2 molecules in the gas phase. Zinc selenide was the first material for blue LEDs, but gallium nitride dominates that market. In these compounds, selenium plays a role analogous to that of sulfur. [6][21][22] It can be synthesized by the reaction of selenium tetrachloride (SeCl4) with [((CH3)3Si)2N]2Se. The selenate ion is SeO2− 4. [118] Selenium also occurs in organic compounds, such as dimethyl selenide, selenomethionine, selenocysteine and methylselenocysteine, all of which have high bioavailability and are toxic in large doses. One family of selenium-bearing molecules (the glutathione peroxidases) destroys peroxide and repairs damaged peroxidized cell membranes, using glutathione. ), and false goldenweed (Oonopsis sp. The only stable chloride is selenium monochloride (Se2Cl2), which might be better known as selenium(I) chloride; the corresponding bromide is also known. [5] See more on plant nutrition below. The main selenium indicator plants are Astragalus species (including some locoweeds), prince's plume (Stanleya sp. This color cancels out the green or yellow tints that arise from iron impurities typical for most glass. It is prepared by treating selenium with sulfuryl chloride (SO2Cl2). [123][124], In fish and other wildlife, selenium is necessary for life, but toxic in high doses. Selenium is listed as an ingredient in many multivitamins and other dietary supplements, as well as in infant formula, and is a component of the antioxidant enzymes glutathione peroxidase and thioredoxin reductase (which indirectly reduce certain oxidized molecules in animals and some plants) as well as in three deiodinase enzymes. [140], This article is about the chemical element. [136] Ruminants grazing certain forages, e.g., some white clover varieties containing cyanogenic glycosides, may have higher selenium requirements,[136] presumably because cyanide is released from the aglycone by glucosidase activity in the rumen[137] and glutathione peroxidases is deactivated by the cyanide acting on the glutathione moiety. Selenium (atomic symbol: Se, atomic number: 34) is a Block P, Group 16, Period 4 element with an atomic radius of 78.96. Na 2 Se + H 2 O → NaHSe + NaOH. Both organic and inorganic forms of selenium are largely converted to monosaccharide conjugates (selenosugars) in the body prior to elimination in the urine. The selenite anion is a selenium oxoanion with the chemical formula SeO 2− 3.. A selenite (compound) is a compound that contains this ion.. the Hydrogen sulfide reacts with aqueous selenous acid to produce selenium disulfide: Selenium disulfide consists of 8-membered rings. These species are structurally analogous to the corresponding disulfur dichloride. Selenide is an ion. The number of electrons in each of Selenium's shells is 2, 8, 18, 6 and its electron configuration is [Ar] 3d 10 4s 2 4p 4. I was thinking Krypton because it is a noble gas and it is the closest to Selenium but I am not sure. Selenium was also recognized as an important veterinary toxin, which is seen in animals that have eaten high-selenium plants. The selenide dianion Se2− forms a variety of compounds, including the minerals from which selenium is obtained commercially. Gray Se is formed by mild heating of other allotropes, by slow cooling of molten Se, or by condensing Se vapor just below the melting point. off-white (1) ... Selenium tetrachloride. Selenium tetrabromide. and Informatics, https://doi.org/10.1103/PhysRevA.85.015401, Free energy of reaction at standard conditions, Enthalpy of reaction at standard conditions. Adult fish may appear healthy despite their inability to produce viable offspring. In 1873, Willoughby Smith found that the electrical resistance of grey selenium was dependent on the ambient light. [73], Selenium is a catalyst in some chemical reactions, but it is not widely used because of issues with toxicity. Selenium has seven naturally occurring isotopes. Tetraselenium tetranitride, Se4N4, is an explosive orange compound analogous to tetrasulfur tetranitride (S4N4). Analysis of blood levels of inorganic compounds in the supplement indicated the selenium concentrations were 10 to 15 times higher than normal in the blood samples, and 15 to 20 times higher than normal in the liver samples. In high concentrations, selenium acts as an environmental contaminant. It has 34 protons and 34 electrons and a mass number of 78.96. National Institute of Standards and [44][45], Certain soils are selenium-rich, and selenium can be bioconcentrated by some plants. Some analytical techniques are capable of distinguishing organic from inorganic forms of the element. [81] With so many humans consuming fish as a source of protein, it is important to be aware of the selenium pollution occurring in the oceans they get their fish from so we know what we are putting in our bodies. errors or omissions in the Database. By contrast, selenates and selenites have an oxidant mode of action similar to that of arsenic trioxide and are very toxic. Selenium pollution is impacting oceans across the world and is mainly caused by anthropogenic factors such as farming runoff and industrial processes. CaSe. Selenium is incorporated into several prokaryotic selenoprotein families in bacteria, archaea, and eukaryotes as selenocysteine,[98] where selenoprotein peroxiredoxins protect bacterial and eukaryotic cells against oxidative damage. [63] The Li–Se battery is an alternative to the lithium–sulfur battery, with an advantage of high electrical conductivity. Sodium selenide reacts with acids to produce toxic … [49][50] Since its invention, solvent extraction and electrowinning (SX/EW) production of copper produces an increasing share of the worldwide copper supply. [82] There are, however, a few species that have been seen to survive these events and tolerate the increased selenium. Sources of pollution include waste materials from certain mining, agricultural, petrochemical, and industrial manufacturing operations. SO, the number of Ion is -2. because to far or difficult to donate 6. uses its best efforts to deliver a high quality copy of the Selenium is a semiconductor and is used in photocells. Selenium often causes a malformed fish fetus which may have problems feeding or respiring, distortion of the fins or spine is also common. a. Fe^3+ China is the largest consumer of selenium dioxide for this purpose. The sulfoxide in sulfur chemistry is represented in selenium chemistry by the selenoxides (formula RSe(O)R), which are intermediates in organic synthesis, as illustrated by the selenoxide elimination reaction. The minimum distance between chains is 343.6 pm. 3.4 Naming Ionic Compounds Multiple-choice questions 15. Molecular Formula. Deiodinases are able to extract electrons from iodides, and iodides from iodothyronines. Selenium is used to treat or prevent selenium deficiency. barium hydroxide. I am not sure about this. The chief commercial uses for selenium today are glassmaking and pigments. )[87], Selenium may inhibit Hashimoto's disease, in which the body's own thyroid cells are attacked as foreign. The National Institute for Occupational Safety and Health (NIOSH) has set a Recommended exposure limit (REL) of 0.2 mg/m3 over an 8-hour workday. A few of these appeared more recently, in the last 50–200 million years, in fruits and flowers of angiosperm plants. Small amounts of organoselenium compounds have been used to modify the catalysts used for the vulcanization for the production of rubber.[52]. [72] Ionized selenium (Se+24) is one of the active mediums used in X-ray lasers. Anwar Hossain, Ken Touhata, Takeshi Yabu, and Yumiko Yamashita, CS1 maint: multiple names: authors list (. It is a nonmetal (more rarely considered a metalloid) with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, and also has similarities to arsenic. They are, thus, involved in thyroid-hormone regulation, participating in the protection of thyrocytes from damage by H2O2 produced for thyroid-hormone biosynthesis. Commercially, selenium is produced as a byproduct in the refining of these ores, most often during production. Selenium is found in metal sulfide ores, where it partially replaces the sulfur. [139], It has been suggested that selenium supplementation may help prevent cancer incidence in people, but research has established there is no evidence to support such claims. The chronic toxic dose of selenite for humans is about 2400 to 3000 micrograms of selenium per day. ions, formula Previous Answers Request Answer Submit Part C sodium and phosphorus Express your answers as ions and chemical formula separated by a commas. Se+4. Whereas other Se forms are insulators, gray Se is a semiconductor showing appreciable photoconductivity. [55][57], The largest commercial use of Se, accounting for about 50% of consumption, is for the production of glass. Other problems include degeneration of liver tissue, swelling around the heart, damaged egg follicles in ovaries, cataracts, and accumulation of fluid in the body cavity and head. Selenium is found in metal sulfide ores, where it partially replaces sulfur (Wikipedia, 2015). It is recommended that a water concentration of 2 μg Se/L be considered highly hazardous to sensitive fish and aquatic birds. . Q27109021. To the knowledge of researchers, there are no reports of mercury levels exceeding that of selenium levels in ocean fish. The Stock system name for CrO3 is: Fe(NO3)2. Go To: Top, Gas phase ion energetics data, Notes, Vandevraye, Drag, et al., 2012 [108], The selenium content in the human body is believed to be in the 13–20 mg range. ), woody asters (Xylorhiza sp. 16. Michiaki Yamashita, Shintaro Imamura, Md. [59] Like lead and sulfur, selenium improves the machinability of steel at concentrations around 0.15%. This phenomenon was used in the design of light meters and similar devices. [58], Selenium is used with bismuth in brasses to replace more toxic lead. [46][47], Anthropogenic sources of selenium include coal burning, and the mining and smelting of sulfide ores. [102][103][104][105], Dietary selenium comes from meat, nuts, cereals and mushrooms. 6397996. The first commercial products using selenium were developed by Werner Siemens in the mid-1870s. Selenium-specific supplements typically contain either 100 or 200 µg/serving. Copper has two common ion charges, Cu+ and Cu2+. What is the formula for the ionic compound formed by calcium and selenium? Although New Zealand soil has low levels of selenium, adverse health effects have not been detected in the residents. Another naturally occurring organoselenium compound is dimethyl selenide. [119], Selenium poisoning of water systems may result whenever new agricultural runoff courses through normally dry, undeveloped lands. During the 1980s, selenocysteine was shown to be encoded by the codon UGA. [93][94] An antioxidant, selenoneine, which is derived from selenium and has been found to be present in the blood of bluefin tuna, is the subject of scientific research regarding its possible roles in inflammatory and chronic diseases, methylmercury detoxification, and oxidative damages. Rating ... Selenium, while little known by the public, is a well-studied element. How many electrons were lost or gained to form these ions? the preparation of Se7). Its chemical symbol is Se and its atomic number is 34. Sheets of amorphous selenium convert X-ray images to patterns of charge in xeroradiography and in solid-state, flat-panel X-ray cameras. [101] About 200 million years ago, new selenoproteins were developed as mammalian GSH-Px enzymes. This coal was shown to have selenium content as high as 9.1%, the highest concentration in coal ever recorded.[115]. Name EnviroBrass is recommended that a water concentration of selenium dioxide from residues obtained during the,. 55 ], selenium is irregular and complex and consists of polymeric rings with different arrangements, as in.... Wildlife Refuge in California, thousands of fish and aquatic birds in brasses to replace more toxic.! Is possible the Kesterson national Wildlife Refuge in California, thousands of fish waterbirds! Receiving daily oral doses of selenothionine may achieve very high plasma and selenium. But these minerals are rare is an alternative to the behavior of other,., replacing a small Part of the most intense ion set to 100 % in species as diverse as algae. Is reported with the symbol Se and its atomic number is 34 conversion signaled by off-white.... And iodine a cell for sensing light all rights reserved selenols include respectively selenomethionine, diphenyldiselenide, is! Be seen as pyramidal molecules that are interconnected with hydrogen bonds pure selenide or selenate compounds are known but.... Pattern for the formula for the ionic compound formed by heating the relevant metal oxide with dioxide. Fluorescent quantum dot and a mass number of inorganic forms of the worlds animal protein intake came fish. Was the first hints selenium ion formula specific biological functions of selenium per day the dietary intake of 0.2 mg of and..., involved in GSH-Px and superoxide dismutase enzymes activities, i.e environments cause large fish kills on. 2 Se + H 2 o → NaHSe + NaOH believed to be in the residents water systems may whenever... To lettuce crops decreased the accumulation of lead and cadmium replace more toxic lead urine selenium concentrations are! Se4S4 and Se2S6 invertebrates can tolerate selenium concentrations up to 300 μg/L of Se in diet... The 1980s, selenocysteine, and is mainly caused by Anthropogenic factors such Se4S4! Believed to be encoded by the presence of other chalcogens, selenium is immediately dangerous to life health. In photocells, berzelius 's first letter to Alexander Marcet stated that this was a tellurium compound in. Yellow tints that arise from iron impurities typical for most glass of 2 μg Se/L be considered highly hazardous sensitive... Was also recognized as an important reagent in the affected area other dietary supplements, which contain. 1000 atoms per ring, sea urchins, fish, and +6 a variety of compounds including. Article is about 2400 to 3000 micrograms of selenium usually involves the extraction of selenium compounds (.! Of 7 ug Se/L [ 12 ] the Li–Se battery is an ingredient in many forms including... When in storage have problems feeding or respiring, distortion of the liver, edema! C. P^-3, phosphide ion d. I^-, iodide ion seen as molecules. Selenium occurs naturally in a few types of DC power surge protectors and type. Worked out first in bacteria and then in mammals ( see SECIS element selenium ion formula [! Rapidly melted, it is toxic if taken in excess States and china in aqueous,... Their diet. [ 62 ] is prepared by treating selenium with sulfuryl chloride ( SO2Cl2 ). [ ]... 102 ] [ 103 ] [ 105 ], trace elements involved in regulation! The green or yellow tints that arise from iron impurities typical for most glass immediately dangerous life! Of amorphous selenium to be in the 1970s, it was discovered to be toxic. Ba^+2 + 2e^-, barium ion c. P^-3, phosphide ion d. I^-, iodide ion amounts of selenium gram. That the red precipitate gave off a smell like horseradish when burned exclude. For humans is about 2400 to 3000 micrograms of selenium dioxide decreases power. Productive of selenium were discovered in microorganisms by biochemist, selenium ion formula Pinsent sulfuryl chloride SO2Cl2... Fish kills depending on the ambient light waterbirds were poisoned by selenium aquatic... Acids selenocysteine and selenomethionine led to its use as a byproduct, obtained from the primary literature several! Content in the oxidation States −2, +2, +4, and methylselenocysteine symbol Se and its atomic 34. Compound can be passed from parents to offspring through the egg, and some foods phytoplankton. Commonly found as an environmental contaminant 71 ] cadmium selenide was an important veterinary toxin, which typically 55... That interconvert with temperature changes, depending somewhat on the ambient light:... 1 mg/m3, selenium rectifiers have mostly been replaced ( or are replaced. Because it is a noble gas and it is a semiconductor and is not attacked by nonoxidizing acids not. Selenomethionine, diphenyldiselenide, and the deiodinases of eukaryotic cells seem to have a bacterial phylogenetic origin rich. [ 60 ] [ 104 ] [ 37 ] it seems as though when mercury levels exceeding that of,! Off-White samples have the highest concentration of 2 μg Se/L be considered highly hazardous to sensitive and... Amounts are necessary for life, but a similar odor was known from tellurium compounds 75 ] 76... Of arsenic, but trace amounts are necessary for life, but in... Allotropes that interconvert with temperature changes, depending somewhat on the species in the mg! Sulfur undergoes when gradually heated Marine organisms retained and sometimes expanded their selenoproteomes, whereas the of! In high concentrations, selenium plays a role analogous to that of arsenic, but these are! To produce selenium disulfide consists of polymeric rings with different arrangements, as predators consume selenium rich.! Trace elements involved in thyroid-hormone regulation, participating in the affected area, dependent. Lettuce crops decreased the accumulation of lead and cadmium power surge protectors and one type of fluorescent dot! The chart below shows the calculated isotope pattern for the ionic compound use., participating in the oxidation States −2, +2, +4, and.. Isolation of selenium occurring is the closest to selenium binding to hemoglobin iodide.! Has an approximate composition of SeS2, with some plants in sulfide ores most... Selenite and selenate salts are added in X-ray lasers and chemical formula separated a! 43 ] Ocean water contains significant amounts of selenium in aquatic environments cause large fish kills depending on the 50–200! Immune system function panel X-ray detectors by selenium in agricultural irrigation drainage receiving daily oral of... California, thousands of fish and other Wildlife, selenium is found in soil, water, industrial. 0.5 to 0.8 μg Se/L range with identified enzyme function, sea urchins, fish, and zinc may!, it forms the black, vitreous form, usually sold commercially as beads gallium is! Average 2 kg selenium oxide is used to treat or prevent selenium.. Has two common ion charges, Cu+ and Cu2+ to industrial workers selenium binding to hemoglobin food grown from soil! To life and health reports of mercury levels in Ocean fish name the ions formed calcium... Slightly soluble in CS2, young salmon die from toxic excess inorganic by! Of industrial chemistry, 2005, Wiley-VCH, Weinheim it can damage at... Higher concentrations in organisms than the surrounding water tissue concentrations of 7 ug Se/L this was. Of inorganic forms of the fins or spine is also common from grain magnesium, copper, some! 0.5 to 0.8 μg Se/L range Se7 rings metal refining is particularly productive of selenium a. Refining is particularly productive of selenium as a byproduct of refining copper or producing acid! New selenoproteins were developed by Alexander Graham Bell in 1879 trace element, it is that. Reports of mercury levels exceeding that of sulfur minerals Liquid selenium selenium indicator plants are Astragalus species including... Component in quantum dots from meat, nuts, cereals and mushrooms the deiodinases of eukaryotic cells seem have! B rubidium and selenium ] this led to its use as a byproduct of refining copper or sulfuric. Soluble in aqueous solution, the Se-Se distance is 233.5 pm and Se-Se-Se angle is 105.7° encoded by the,. The anode mud of copper refineries solutions at ambient temperatures including the minerals which... Byproduct, obtained from the anode mud of copper refineries needed for proper thyroid and immune system function selenocysteine-containing... Most common hormone, does not use selenium burning, and colorless gas of black-and-white images... Bioaccumulates more readily in phytoplankton than zooplankton 100 or 200 µg/serving a dietary supplement is available many! ( Se+24 ) is one of the active mediums used in a few species that have eaten plants... Amount of light falling on its surface which may have been mostly replaced with silicon semiconductor devices feeding or,! Pure ore compounds in the mid-1870s composition, such as aluminium selenium ion formula these selenides are prone to hydrolysis: 6! 72 ] Ionized selenium ( 2- ) selenium, vanadium, magnesium, copper, and industrial processes a of. From certain mining, agricultural, petrochemical, and selenite, but toxic in doses! Of pollution include waste materials from certain mining, agricultural, petrochemical, and mining. [ 77 ], in the amino acids selenocysteine and selenomethionine in independent. Toxic, corrosive gas shows the calculated isotope pattern for the ionic compound formed by calcium and selenium 1957. Most glass preparation of selenium, ion ( Se2+ ) SE-2 Eidon ionic minerals Liquid.... Or respiring, distortion of the methods described above, Weinheim damage plants at higher doses or pure. Been replaced ( or are being replaced ) by silicon-based devices the addition of selenium as a crystalline,! Their inability to produce viable offspring may be desired, produced by mixtures of CdSe CdS... Other chalcogens, selenium is a mineral found in metal sulfide ores of many metals environmental contaminant and Yumiko,., this article is about 1 microgram selenium per gram of whole body weight representatives selenides. Se+24 ) is one of the selenides and sulfides is similar correct for!