4.6.2 - Cation Tests

Question 1

What is a cation!?

Answer 1

Cat ions are positive ions

Question 2

How do you conduct a flame test !?

Answer 2

1. Dip a piece of Nike chrome wire into hydrochloric acid. This wire doesn’t colour the flame and the acid cleans the wire
2. Dip the wire into a sample, a solid or solution. This causes some of the sample to stick onto the wire.
3. Place the tip of the wire into a non-luminous Bunsen flame. 

Question 3

What metal cation produces a red flame !?

Answer 3

.lithium

Question 4

What metal cation produces a yellow flame !?

Answer 4

Sodium

Question 5

What metal cation produces a lilac flame !?

Answer 5

Potassium

Question 6

What metal cation produces a orange-red flame !?

Answer 6

Calcium

Question 7

What metal cation produces a blue-green flame !?

Answer 7

. Copper

Question 8

How do you conduct a sodium hydroxide test !?

Answer 8

1. Dissolve the sample in water.
2. Add a few drops of sodium hydroxide (aq)

Question 9

What metal cation produces a blue precipitate colour !?

Answer 9

Copper ➡️ Cu(OH)2

Question 10

What metal cation produces a green precipitate colour !?

Answer 10

Iron(2➕) ➡️Fe(OH)2

Question 11

What metal cation produces a brown precipitate colour !?

Answer 11

Iron (1➕) ➡️ Fe(OH)3

Question 12

How do you conduct an ammonium test !?

Answer 12

1. Dissolve the sample in water.
2. Add some sodium hydroxide(aq) and warm it.
3. Tested gas involved with damp, red litmus paper (i.e. the ammonia test)