Chemical elements
  Nickel
    History
    Occurrence
    Isotopes
    Energy
    Production
    Preparation
    Application
    Catalyst
    Physical Properties
    Compounds
      Nickel Fluoride
      Nickel Dichloride
      Double Nickel Chlorides
      Nickel Dibromide
      Nickel Di-iodide
      Nickel Chlorate
      Nickel Perchlorate
      Nickel Bromate
      Nickel Iodate
      Tri-nickel Suboxide
      Nickel Suboxide
      Nickel Monoxide
      Nickel Dihydroxide
      Nickelo-nickelic Oxide
      Nickel Dioxide
      Nickel Subsulphide
      Nickel Monosulphide
      Nickel Sesquisulphide
      Tri-nickel Tetrasulphide
      Nickel Disulphide
      Nickel Tetrasulphide
      Nickel Sulphite
      Nickel Thiosulphate
      Nickel Dithionate
      Nickel Sulphate
      Nickel Subselenide
      Nickel Selenide
      Nickel Sesquiselenide
      Nickel Selenite
      Nickel Sesquitelluride
      Nickel Tellurite
      Nickel Chromate
      Nickel Dichromate
      Double Nickel Chromates
      Nickel Molybdate
      Nickel Nitride
      Nickel Azoimide
      Nickelamide
      Nitro-nickel
      Nickel Nitrite
      Nickel Nitrate
      Di-nickel Phosphide
      Nickel Sesquiphosphide
      Nickel Diphosphide
      Nickel Triphosphide
      Nickel Hypophosphite
      Nickel Phosphite
      Nickel Metaphosphate
      Nickel Orthophosphate
      Nickel Pyrophosphate
      Nickel Thio-orthophosphate
      Nickel Thiopyrophosphite
      Nickel Thiopyrophosphate
      Tri-nickel Diarsenide
      Nickel Arsenide
      Nickel Diarsenide
      Nickel Arsenite
      Nickel Orthoarsenate
      Nickel Antimonide
      Nickel Antimonate
      Nickel Thioantimonite
      Nickel Vanadate
      Nickel Carbide
      Nickel Tetracarbonyl
      Nickel Carbonate
      Nickel Monocyanide
      Nickel Cyanide
      Nickel Thiocyanate
      Nickel Thiocarbonate Hexammoniate
      Nickel Subsilicide
      Nickel Orthosilicate
      Nickel Monoboride
      Nickel Borates
    PDB 1a5n-1g2a
    PDB 1g3v-1mn0
    PDB 1mro-1s9b
    PDB 1scr-1xmk
    PDB 1xu1-2cg5
    PDB 2cqz-2jih
    PDB 2jk8-2v4b
    PDB 2vbq-3c2q
    PDB 3c6c-3h85
    PDB 3hdp-3kvb
    PDB 3l1m-3o00
    PDB 3o01-4ubp
    PDB 8icl-9ant

Nickel Dibromide, NiBr2






Nickelous Bromide or Nickel Dibromide, NiBr2, may be obtained in the anhydrous condition by heating the finely divided metal in bromine vapour and subliming the product at bright red heat in the absence of air. A mixture of nitrogen and hydrogen bromide is particularly suitable. It may also be produced by addition of the calculated quantity of dry bromine to finely divided nickel in ether. A yellow salt of composition corresponding to the formula NiBr2.(C2H5)2O results, and this on heating yields the ether-free, anhydrous bromide. The salt usually occurs as golden scales which absorb moisture on exposure to air. The colour, however, varies according to the state of aggregation of the salt from yellow to dark bronze brown. At red heat in the presence of traces of air or moisture some nickelous oxide is formed, but Richards and Cushman could find no evidence of the existence of an oxybromide under such conditions.

The sublimed salt is slowly soluble in hot water, yielding a clear solution, which may be boiled without decomposition. Berthelot states that the solution on standing in air deposits nickel monoxide. This, however, is not the case with the pure substance. The density of the sublimed salt is 4.64 at 28° C.

The trihydrate, NiBr2.3H2O, may be obtained by introducing finely divided nickel into bromine under water, or by dissolving nickel monoxide in aqueous hydrogen bromide. On concentrating the solution, the salt crystallises out in the form of deliquescent needles.

The solubility of nickel bromide in water is as follows:

Temperature ° С010204060100
Grams NiBr2 in 100 grams solution.53.055.056.759.160.460.8


The hexahydrate, NiBr2.6H2O, has been prepared. It melts at 28.5° C., and from the liquid the trihydrate crystallises out. The nonahydrate, NiBr2.9H2O, melting at -2.5° C. without decomposition, has also been isolated.

When ammonia is added to a solution of nickel bromide, beautiful violet crystals of the hexammoniate, NiBr2.6NH3, separate out. These are soluble in concentrated hot ammonium hydroxide, but insoluble in the cold. On boiling with excess of water, nickel dihydroxide is produced. Since cobalt does not yield a similar derivative, the formation of nickel hexammoniate forms a useful method of separating nickel from cobalt.


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