Core Practicals In Paper 2

Question 1

Explain the flame tests for metal ions

Answer 1

Light a Bunsen burner and open the air hole
Pick up a small sample of the solid using a clean wire loop
Hold sample in edge of the flame
Record colour

Question 2

Explain the hydroxide precipitate tests for metal cations

Answer 2

Dissolve a solid salt using distilled water
Add a few drops of dilute sodium hydroxide solution, one at a time
Record colour of any precipitate formed
If white precipitate forms, add excess dilute sodium hydroxide solution to see if it will disappear

Question 3

Explain the test for ammonium ions

Answer 3

Dissolve a little solid salt using distilled water
Add dilute sodium hydroxide solution and warm gently
Remove from flame