- Prepare a mixture of water and acetic acid 4/1.
- Mix 100 ml of this mixture with 1.7 g of bismuth oxynitrate. This is the first solution.
- Dissolve 40 g of potassium iodate in 100 ml of water. This is the second solution.
- Mix together 5 ml of both the first and the second solutions, add 20 ml of acetic acid and 70 ml of water.
- Add a few drops of the prepared solution into the test tube with an alkaloid solution (for example, quinine). An orange precipitate is formed.