Sodium Selenite

Sodium selenite is the inorganic compound with the formula Na2SeO3. This salt is a colourless solid. The pentahydrate Na2SeO3(H2O)5 is the most common water-soluble selenium compound. Sodium selenite is mainly used in the manufacture of colorless glass. The pink color imparted by these selenites cancels out the green color imparted by iron impurities.

Because selenium is an essential element, sodium selenite is an ingredient in some food supplements. The US Food and Drug Administration approved a selenium supplement to animal diets, however the most common form is sodium selenite for pet foods.

Sodium Selenite Pentahydrate BP Grade: Ph Eur Na2SeO3,5H2O -- 263.0 -- 26970-82-1

DEFINITION: Content: 98.5 per cent to 101.5 per cent.

IDENTIFICATION

• Dissolve 50 mg in 5 ml of a mixture of equal volumes of dilute hydrochloric acid and water and heat to boiling. Add 0.05 g of ascorbic acid; a red precipitate is formed which may become black.
• Dissolve 50 mg in a mixture of 1 ml of dilute hydrochloric acid and 5 ml of water. Add 1 ml of barium chloride solution; the solution remains clear.
• It gives reaction of sodium.
• It complies with the limits of the assay.

• TESTS: Solution S: Dissolve 5.0 g in carbon dioxide-free water and dilute to 50.0 ml with the same solvent.
• Appearance of solution: Solution S is clear and colourless.
• Chlorides: Maximum 50 ppm.
• Sulphates and selenates: Maximum 300 ppm (determined as sulphates).
• Iron: Maximum 50 ppm.

Sodium Selenite Anhydrous is also offered as per below mentioned specifications:

• EINECS: 233-267-9
• Molecular Weight  : 172.94
• Sensitive: Hygroscopic
• Appearance: White to off white Crystalline Powde
• Water Solubility: 950 g/L (20° C)
• Selenium Content: 45%
• LOD (By IR): 0.5% max., at 100° C for 1 hr.
• Iron as Fe: 0.005% max.
• Sulphate as SO4: 0.2% max.
• Assay: 98.5% min. ( on dry basis )