Flame tests and chemical reagents are used to identify the ions present in unknown compounds.
Suggest two reasons why platinum is a suitable metal to use as the wire in flame tests.
Why should the platinum wire be cleaned thoroughly between each test?
Why is a luminous Bunsen flame not suitable for carrying out a flame test?
Three metal compounds, AAA, BBB, and CCC, are tested separately with various diagnostic reagents. The results of these tests are shown in the table below:
| Metal compound | Flame test | Aqueous acidified silver nitrate | Aqueous acidified barium chloride | Aqueous sodium hydroxide |
|---|---|---|---|---|
| A | lilac | cream precipitate | no precipitate | no precipitate |
| B | brick-red | no precipitate | white precipitate | white precipitate |
| C | no colour | no precipitate | no precipitate | brown precipitate |
Give the chemical name of compound A A\,A and of compound BBB.
Identify the cation present in compound CCC.
Describe a chemical test, other than heating, that could be used to show that compound C C\,C contains carbonate ions (CO32−\text{CO}_3^{2-}CO32−).
