Tests for anions

• Test for halide ions using silver nitrate solution.
• To test for chloride ions:

  • Add a few drops of nitric acid, followed by a few drops of silver nitrate solution
  • A chloride gives a white precipitate of silver chloride
• To test for bromide:

  • Add a few drops of nitric acid, followed by a few drops of silver nitrate solution
  • A bromide gives a cream precipitate of silver bromide
• To test for iodide:

  • Add a few drops of dilute nitric acid, followed by a few drops of silver nitrate solution
  • An iodide gives a yellow precipitate of silver iodide
• Halide ions are negatively charged elements in the Halogen group 7.
• Test for Carbonates using hydrochloric acid
• To test for carbonate ions:

  • Add some barium chloride solution
  • If carbonate ions are present, they will produce a white precipitate of barium chloride
  • Then add some Hydrochloric acid
  • If there are carbonate ions present, the mixture will fizz to produce carbon dioxide.
  • Once all the barium chloride has reacted, you will end up with a colourless solution containing Barium ions.
• Test for Sulfate ions using barium chloride solution
• To test for sulfate ions:

  • First add some barium chloride solution
  • If there are sulfate ions in the solution, a white precipitate of a barium sulfate will form.
  • Then add some dilute Hydrochloric acid to the test sample.
  • Barium sulfate will not react with dilute hydrochloric acid, so the precipitate will not dissolve.