I had a couple of requests for a summary of tests for ions and functional groups. There are series of standard common tests but any reaction in the syllabus that involves an observable change could be used as a ‘test’ to distinguish between two compounds.

The standard tests can be found here in Practical Guide -aqa This is not a list of every reaction that could be used distinguish between compounds though. Almost all the group 2 and group 7 reactions can be used.

How would you distinguish these pairs of compounds?

1. KF (aq) and KCl(aq)

2. KNO₃ and AgNO₃

3. sodium carbonate and potassium nitrate

4. HNO₃ and H₂SO₄

5. NaCl (aq) and KBr (aq)

6. AgCl (s) and  AgI (s)

7. magnesium nitrate and barium nitrate

8. KCl(s) and KI (s)   using only conc sulphuric acid

9  propanone and propanal

10. propanoic acid and hexane

11. cyclohexane and cyclohexene

12. butan-2-ol and 2-methylpropan-2-ol