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Simplest is the material selenium sulfide, which has medicinal properties. It adopt the diverse structures of elemental sulfur but with some S atoms replaced by Se. Other inorganic selenide sulfide compounds occur as minerals and as pigments. One example is antimony selenosulfide.
Selenium is found in metal sulfide ores, where it substitutes for sulfur. Commercially, selenium is produced as a byproduct in the refining of these ores. Minerals that are pure selenide or selenate compounds are rare. The chief commercial uses for selenium today are glassmaking and pigments. Selenium is a semiconductor and is used in photocells.
Download as PDF; Printable version; In other projects ... move to sidebar hide. Selenium sulfide can refer to either of the following : Selenium disulfide, SeS 2 ...
Selenium compounds are more nucleophilic than the corresponding sulfur compounds and also more acidic. The p K a values of XH 2 are 16 for oxygen, 7 for sulfur and 3.8 for selenium. In contrast to sulfoxides , the corresponding selenoxides are unstable in the presence of β-protons and this property is utilized in many organic reactions of ...
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 in these reactions is almost always stereogenic, and the effect of epimerization at selenium (which is acid-catalyzed and occurs readily) on the elimination reaction is nearly unknown. In one example, separation and warming of selenoxides 1 and 2 revealed that 2 decomposes at 0 °C, while 1 , which presumably has more difficulty ...
A mnemonic is a memory aid used to improve long-term memory and make the process of consolidation easier. Many chemistry aspects, rules, names of compounds, sequences of elements, their reactivity, etc., can be easily and efficiently memorized with the help of mnemonics.
A Magic Triangle image mnemonic - when the terms of Ohm's law are arranged in this configuration, covering the unknown gives the formula in terms of the remaining parameters. It can be adapted to similar equations e.g. F = ma, v = fλ, E = mcΔT, V = π r 2 h and τ = rF sinθ.