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Selenium is toxic in high concentrations. As sodium selenite, the chronic toxic dose for human beings was described as about 2.4 to 3 milligrams of selenium per day. [7] In 2000, the US Institute of Medicine set the adult Tolerable upper intake levels (UL) for selenium from all sources - food, drinking water and dietary supplements - at 400 μg/day. [8]
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 ...
A bath salt tablet shaped like a seashell. Some bath salts act as water softeners and change the way soap rinses. High concentrations of salts increase the density of the water and increase buoyancy, which makes the body feel lighter in the bath. Very high concentrations of salts in water are used in many isolation tank therapies. Isolation ...
A selenate selenite is a chemical compound or salt that contains selenite and selenate anions (SeO 3 2-and SeO 4 2-). These are mixed anion compounds . Some have third anions.
Salts of selenous acid are called selenites. These include silver selenite (Ag 2 SeO 3) and sodium selenite (Na 2 SeO 3). Hydrogen sulfide reacts with aqueous selenous acid to produce selenium disulfide: + + Selenium disulfide consists of 8-membered rings.
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').
SeO 2 is considered an acidic oxide: it dissolves in water to form selenous acid. [6] Often the terms selenous acid and selenium dioxide are used interchangeably. It reacts with base to form selenite salts containing the SeO 2− 3 anion. For example, reaction with sodium hydroxide produces sodium selenite: SeO 2 + 2 NaOH → Na 2 SeO 3 + H 2 O
Gypsum occurs in nature as flattened and often twinned crystals, and transparent, cleavable masses called selenite. Selenite contains no significant selenium; rather, both substances were named for the ancient Greek word for the Moon. Selenite may also occur in a silky, fibrous form, in which case it is commonly called "satin spar".