Selenium Dioxide Micron Powder

Selenium dioxide is the chemical compound with the formula SeO2. This colorless solid is one of the most frequently encountered compounds of selenium. Selenium dioxide appears as a white or creamy-white volatile lustrous crystal or crystalline powder with a pungent sour smell. Melting point of selenium dioxide is approximately 340℃. Selenium dioxide micron powder is prepared by oxidation of selenium by burning in air or by reaction with nitric acid or hydrogen peroxide, but perhaps the most convenient preparation is by the dehydration of selenous acid. Selenium dioxide powder imparts a red colour to glass. It is used in small quantities to counteract the colour due to iron impurities and so to create (apparently) colourless glass. In larger quantities, it gives a deep ruby red colour. Selenium dioxide is the active ingredient in some cold-bluing solutions. It is also used as a toner in photographic developing.