Chemical elements
    Physical Properties
    Chemical Properties
      Hydrogen Selenide
      Selenium Fluorides
      Selenium Monochloride
      Selenium Tetrachloride
      Selenium Monobromide
      Selenium Tetrabromide
      Selenium Chlorobromides
      Selenium Oxyfluoride
      Selenium Oxychloride
      Sulphur Selenium Oxytetrachloride
      Selenium Oxybromide
      Chloroselenic Acid
      Selenium Dioxide
      Selenious Acid
      Selenium Trioxide
      Selenic Acid
      Perselenic Acid
      Selenium Sulphoxide
      Selenotrithionic Acid
      Diselenotrithionic Acid
      Selenopentathionic Acid
      Selenium Nitride
      Nitrosylselenic Acid
      Phosphorus Subselenide
      Phosphorus Monoselenide
      Tetraphosphorus Triselenide
      Phosphorus Triselenide
      Phosphorus Pentaselenide
      Phosphorus Chloroselenide
      Selenophosphates and Oxyselenophosphates
      Carbon Diselenide
      Carbon Subselenides
      Carbon Oxyselenide
      Carbon Sulphidoselenide
      Cyanogen Monoselenide
      Cyanogen Diselenide or Selenocyanogen
      Cyanogen Triselenide
      Selenocyanic Acid
      Ammonium Selenocyanate
      Caesium Triselenocyanate
      Copper Selenocyanate
      Lead Selenocyanate
      Magnesium Selenocyanate
      Mercurous Selenocyanate
      Mercuric Selenocyanate
      Potassium Selenocyanate
      Silver Selenocyanate
      Sodium Selenocyanate
      Zinc Selenocyanate
      Silicon Selenide
    Detection and Estimation

Selenium Oxybromide, SeOBr2

Selenium Oxybromide, SeOBr2, may be prepared by adding the calculated amount of fused selenium to pure selenium dioxide in a cooled flask and dropping in the requisite quantity of bromine slowly. The mixture is then warmed until the whole of the oxide has dissolved.

The oxybromide is a reddish-yellow solid, melting at 41.5° C. It has a boiling-point of 217° C. at 740 mm., with considerable decomposition. It decomposes so readily on heating that it cannot be purified by distillation even under reduced pressure. Its electrical conductivity is 6×10-5 mho at 40° to 50° C.

It is slowly converted by water into a mixture of selenious and hydrobromic acids. It is soluble in carbon disulphide, chloroform, benzene, toluene, xylene and carbon tetrachloride.

Selenium oxybromide is a very active chemical agent. It reacts with sulphur in the cold with the evolution of sulphur dioxide, and with selenium to form the monobromide. Phosphorus reacts violently with the solid; silicon and carbon are unattacked.

The majority of the metals react with selenium oxybromide with the production of the corresponding metal bromides, selenium dioxide and selenium monobromide. Zinc, cadmium, chromium, nickel, cobalt, tungsten and tantalum, however, are not attacked even after prolonged heating at 100° C.

Potassium chlorate liberates bromine from the oxybromide, whilst potassium perchlorate, permanganate, dichromate and chromium trioxide are without action on it.

By bubbling dry air at 60° C. through the oxybromide, bromine is liberated; this is stated by Lenher to be due to a primary dissociation into the dioxide and tetrabromide, followed by a secondary dissociation of the tetrabromide into the monobromide and bromine.

Carbon monoxide and sulphur dioxide have no action on the oxybromide.

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