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Selenite, satin spar, desert rose, and gypsum flower are crystal habit varieties of the mineral gypsum.. All varieties of gypsum, including selenite and alabaster, are composed of calcium sulfate dihydrate (meaning that it has two molecules of water), with the chemical formula CaSO 4 ·2H 2 O. Selenite contains no selenium, the similar names both derive from Greek selḗnē (σελήνη 'Moon').
Iron(III) selenite is an inorganic compound with the chemical formula Fe 2 (SeO 3) 3. It exists anhydrous form and as various hydrates. It exists anhydrous form and as various hydrates. The heptahydrate is produced by the reaction of ferric chloride and selenous acid (or sodium selenite ) at a pH of 1.05. [ 3 ]
Selenite refers to the anion with the chemical formula Se O 2− 3. It is the oxyanion of selenium. It is the selenium analog of the sulfite ion, SO 2− 3. Thus selenite is pyramidal and selenium is assigned oxidation state +4. Selenite also refers to compounds that contains this ion, for example sodium selenite Na 2 SeO 3 which is a common ...
Sodium selenite is the inorganic compound with the formula Na 2 SeO 3. This salt is a colourless solid. The pink coloured pentahydrate Na 2 SeO 3 (H 2 O) 5 is the most common water-soluble selenium compound.
Selenite (ion), anion is a selenium oxoanion with the chemical formula SeO 3 2−. Selenous acid, the conjugate acid, with the formula H 2 SeO 3; Salts of this anion: Silver selenite, an inorganic compound of formula Ag 2 SeO 3; Sodium selenite, a salt, a colourless solid, and the most common water-soluble selenium compound
Selenite "sword", 22.6 by 2.6 by 1.6 centimetres (8.90 in × 1.02 in × 0.63 in). A small version of the giant crystals, likely found in a natural cavity in the mine. A scientific team coordinated by Paolo Forti, specialist of cave minerals and crystallographer at the University of Bologna (Italy), explored the cave in detail in 2006.
Potassium selenate is produced by the reaction of selenium trioxide and potassium hydroxide.. SeO 3 + 2 KOH → K 2 SeO 4 + H 2 O. Alternatively, it can be made by treating selenous acid with potassium hydroxide, followed by oxidation of the resulting potassium selenite with bromine water.
The element selenium exhibits several valence states. Selenate is the least reduced, followed by selenite, and elemental selenium; selenide is even more reduced than elemental selenium. [6] The valence state is an important factor to the toxicity of selenium. Selenate is the form required by organisms that need selenium as a micronutrient.