Names | |
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IUPAC name
Sodium selenate
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Identifiers | |
3D model (JSmol)
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ChEBI | |
ECHA InfoCard | 100.033.169 |
EC Number | 236-501-8 |
PubChem CID
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UNII | |
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Properties | |
Na2O4Se | |
Molar mass | 188.95 g·mol−1 |
Appearance | White or grey powder |
Density | 3.098 g/cm3 |
soluble | |
Pharmacology | |
A12CE01 (WHO) | |
Hazards | |
EU classification (DSD) (outdated)
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Toxic (T) Dangerous for the environment (N) |
R-phrases (outdated) | R23/25, R33, R50/53 |
S-phrases (outdated) | (S1/2), S20/21, S28, S45, S60, S61 |
NFPA 704 | |
Flash point | Non-flammable |
Related compounds | |
Other anions
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Sodium sulfate |
Other cations
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Potassium selenate |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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what is ?) | (|
Infobox references | |
Sodium selenate is the inorganic compound with the formula Na
2SeO
4, not to be confused with sodium selenite. It exists as the anhydrous salt, the heptahydrate, and the decahydrate. These are white, water-soluble solids. The decahydrate is a common ingredient in multivitamins and livestock feed as a source of selenium. The anhydrous salt is used in the production of some glass. Although the selenates are much more toxic, many physical properties of sodium selenate and sodium sulfate are similar.
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.
It was prepared shortly after the discovery of Selenium by Jöns Jacob Berzelius in 1817.
One of the earliest applications of sodium selenate was in the glass industry. Selenium produces a red hue in glass The molten glass is treated with sodium selenate and then arsenic trioxide to reduce the compound and provide elemental selenium. Sodium selenate is also used as a decolorizing agent in glass production. The red hue it gives glass is complementary to the green hue given by ferrous oxides in the manufacturing process. When used together, the two compound produce a colorless glass.
Sodium selenate is a common ingredient in some insecticides used against mites, aphids, and mealybugs. For most insects, a dose of 10 mg/kg is enough to be fatal. It is also used in some fungicides.