Testing for anions (halides)

Question 1

What are halides

Answer 1

Halogen ions, only from group 7

Question 2

Cl^- (Chloride ion)

Answer 2

Step 1) add nitric acid (cannot use hydrochloric acid because it contains chloride ions which will interfere with the test) to remove possible carbonate impurities
Step 2) add silver nitrate solution
Step 3) observe colour of precipitate
Cl^-(aq) + Ag^+(aq) ->AgCl(s)
white ppt (precipitate)

Question 3

Br^- (Bromide ion)

Answer 3

Step 1) add nitric acid (cannot use hydrochloric acid because it contains chloride ions which will interfere with the test) to remove possible carbonate impurities
Step 2) add silver nitrate solution
Step 3) observe colour of precipitate
Br^-(aq) + Ag^+(aq) ->AgBr(s)
cream ppt (precipitate)

Question 4

I^- (Iodide ion)

Answer 4

Step 1) add nitric acid (cannot use hydrochloric acid because it contains chloride ions which will interfere with the test) to remove possible carbonate impurities
Step 2) add silver nitrate solution
Step 3) observe colour of precipitate
I^-(aq) + Ag^+(aq) ->AgI(s)
yellow ppt (precipitate)