Required practical: Electrolysis

Question 1

Step 1

Answer 1

Pour 50cm3 of copper chloride (aq) solution into a beaker

Question 2

Step 2

Answer 2

Place a Petri dish on top of the beaker with 2 holes
Place 2 graphite rods into (electrodes) each hole - these will not react as they are inert

Question 3

Step 3

Answer 3

Attach wires to these rods and attach these to a power supply

Question 4

Step 4

Answer 4

Select 4V and turn the power supply on

Question 5

What would the results be for electrolysing copper chloride?

Answer 5

At the cathode, copper is being produced as it is less reactive than hydrogen
At the anode, chlorine gas is being produced as chlorine is a halogen. This means it will be produced.

Question 6

How can we test to see if chlorine gas is being made?

Answer 6

By holding damp blue litmus paper near the anode we can test for chlorine as it becomes bleached

Question 7

What would the results be for electrolysing sodium chloride?

Answer 7

At the cathode, hydrogen gas would be produced rather than potassium as potassium is more reactive than hydrogen
At the anode, chlorine gas would still be produced as chlorine is a halogen

Question 8

How can we test for hydrogen?

Answer 8

Testing it with a lit splint - if it’s present there will a squeaky pop