Reactions of halides

• The reducing power of Halides increases down the group.

  This is because as you go down the group the attraction between the outer electron and the nucleus gets weaker because ions get larger and the inner electrons increase creating more shielding
• reacting chlorine or fluorine with sulfuric acid?

  HCl and HF gas are formed. Misty fumes will be seen as the gas comes to contact with the moisture in the air.

  Cl- and F- aren’t stron enough reducing agents to reduce sulfuric acid, so the reaction will stop. This is not a redox.
• • Reacting bromine halides with sulfuric acids will give misty fumes of hydrogen bromide
  • Bromide ions will react with it in a redox
  • the reaction them proceeds to produce choking fumes of sulfur dioxide, and orange fumes of bromine gas
• • Reacting iodine with sulfuric acid will give the same initial reaction but then the iodine will reduce the sulfuric acid
  • It will also reduce the SO2 and H2S
  • H2S is toxic and smells like rotten eggs
• • Hydrogen halides are acidic gases.
  • They dissolve in water .
  • In air the form misty fumes
  • hydrogen chloride—> hydrochloric acid
  • hydrogen bromide—> hydrobromic acid
  • Hydrogen iodide —> hydroiodic acid
• Hydrogen halides react with ammonia to give white fumes
• How do you test for halides?

  add dilute nitric acid then silver iterate solution.

  a precipitate of silver halide is formed
• fluoride percipitate?

  non, AgF is insoluble
• Chloride percipitate?

  white
• Bromide percipitate?

  cream
• Iodide‘s percipitate?

  yellow
• If the precipitates look similar what can you use to test for the halide ions?

  ammonia
• AgCl?

  dissolves in dilute ammonia
• AgBr?

  remains if dilute ammonia is added, but dissolves in concentrated ammonia
• AgI?

  does not dissolve in ammonia (concentrated or dilute)