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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 +:
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 ...
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. The terms used in ligand naming are selanido, or hydrogenselenido. [1]
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 ...
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.
Analogous to the behavior of other chalcogens, selenium forms hydrogen selenide, H 2 Se. It is a strongly odiferous, toxic, and colorless gas. It is more acidic than H 2 S. In solution it ionizes to HSe −. The selenide dianion Se 2− forms a variety of
This hydrolysis occurs because of the extreme basicity of the Se 2− ion. Na 2 Se + H 2 O → NaHSe + NaOH. 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 structure of sodium oxide has been determined by X-ray crystallography.Most alkali metal oxides M 2 O (M = Li, Na, K, Rb) crystallise in the antifluorite structure.In this motif the positions of the anions and cations are reversed relative to their positions in CaF 2, with sodium ions tetrahedrally coordinated to 4 oxide ions and oxide cubically coordinated to 8 sodium ions.