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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.
As a crystalline solid, the compound can be seen as pyramidal molecules that are interconnected with hydrogen bonds. In solution it is a diprotic acid: [3] H 2 SeO 3 ⇌ H + + HSeO − 3 (pK a = 2.62) HSeO − 3 ⇌ H + + SeO 2− 3 (pK a = 8.32) It is moderately oxidizing in nature, but kinetically slow. In 1 M H +: H 2 SeO 3 + 4 H + + 4 e − ...
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 ...
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 ...
Side effects in dogs and cats include hypersalivation, diarrhea, loss of appetite, and vomiting. [12] [16] Eight percent of dogs taking maropitant at doses meant to prevent motion sickness vomited right after, likely due to the local effects maropitant had on the gastrointestinal tract. Small amounts of food beforehand can prevent such post ...