Testing for Halide Ions

Question 1

What is the first step in testing for halide ions?

Answer 1

Add acidified silver nitrate (H+/AgNO3 (aq))

Question 2

Why do we add acidified silver nitrate when testing for halide ions?

Answer 2

The HNO3 neutralises and carbonate or hydroxide impurities present which interfere with the halide test.

Question 3

What does Ag2CO3 form?

Answer 3

White precipitate

Question 4

What does AgOH form?

Answer 4

Brown precipitate

Question 5

What is the second step in testing for halides?

Answer 5

Add aqueous ammonia (NH3)

Question 6

What is the result of adding AgNO3 dropwise to a solution containing F-?

Answer 6

No precipitate AgF(aq)

Question 7

What is the result of adding AgNO3 dropwise to a solution containing Cl-?

Answer 7

White precipitate AgCl(s)

Question 8

What is the result of adding AgNO3 dropwise to a solution containing Br-?

Answer 8

Cream precipitate AgBr(s)

Question 9

What is the result of adding AgNO3 dropwise to a solution containing I-?

Answer 9

Pale yellow precipitate AgI(s)

Question 10

What is the result of adding NH3 to AgF(aq)?

Answer 10

No reaction

Question 11

What is the result of adding NH3 to AgCl(s)?

Answer 11

AgCl(s) dissolves in dilute NH3(aq)

Question 12

What is the result of adding NH3 to AgBr(s)?

Answer 12

AgBr(s) dissolves in conc NH3(aq)

Question 13

What is the result of adding NH3 to AgI(s)?

Answer 13

AgI(s) will not dissolve