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Hydrogen selenide is hazardous, being the most toxic selenium compound [3] and far more toxic than its congener hydrogen sulfide. The threshold limit value is 0.05 ppm. The gas acts as an irritant at concentrations higher than 0.3 ppm, which is the main warning sign of exposure; below 1 ppm, this is "insufficient to prevent exposure", while at ...
Sodium hydroselenide is an inorganic compound with the chemical formula Na Se H. It is a salt of hydrogen selenide. It consist of sodium cations Na + and hydroselenide anions − SeH. Each unit consists of one sodium, one selenium, and one hydrogen atom. Sodium hydroselenide is a selenium analog of sodium hydroxide NaOH.
Sample of cadmium selenide, a pigment. The parent inorganic selenide is hydrogen selenide (H 2 Se). It is a colorless, malodorous, toxic gas. It dissolves in aqueous solution, to give the hydrogenselenide or biselenide ion HSe −. At higher pH, selenide forms. Solutions of hydrogen selenide and selenide are oxidized by air to give elemental ...
A hydroselenide (or biselenide or selanide) is an ion or chemical compound containing the [SeH] − ion. The radical HSe is a pseudohalogen.Hydroselenide can be a ligand in transition metal complexes where it can be attached to a single atom, or bridge two atoms.
In solution it ionizes to HSe −. The selenide dianion Se 2− forms a variety of compounds, including the minerals from which selenium is obtained commercially. Illustrative selenides include mercury selenide (HgSe), lead selenide (PbSe), zinc selenide (ZnSe), and copper indium gallium diselenide (Cu(Ga,In)Se 2). These materials are ...
Similarly, sodium selenide is readily oxidized to polyselenides, a conversion signaled by off-white samples. Sodium selenide reacts with acids to produce toxic hydrogen selenide gas. Na 2 Se + 2 HCl → H 2 Se + 2 NaCl. The compound reacts with electrophiles to produce the selenium compounds.
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.
Sodium selenate is produced by oxidation of selenium, first with nitric acid, producing selenous acid. The selenous acid is neutralized to form sodium selenite. The sodium selenite is oxidized in a basic medium hydrogen peroxide to form a selenate, which is then spray-dried. [3] Se + 2HNO 3 → H 2 SeO 3 + NO + NO 2 H 2 SeO 3 + Na 2 CO 3 → Na ...