Electrochemistry

Which statement about electrolysis is correct?

• Electrons move through the electrolyte from the cathode to the anode.

• Electrons move towards the cathode in the external circuit.

• Negative ions move towards the anode in the external circuit.

• Positive ions move through the electrolyte towards the anode during electrolysis.

The diagram shows a circuit used to electrolyse aqueous copper(II) sulfate.

Which arrows indicate the movement of the copper ions in the electrolyte and of the electrons in the external circuit?

• A

• B

• C

• D

Which statements about the electrolysis of concentrated copper(Il) chloride are correct?

1 Electrons are transferred from the cathode to the copper(l) ions.

2 Electrons move round the external circuit from the cathode to the anode.

3 Chloride ions are attracted to the anode.

4 Hydroxide ions transfer electrons to the cathode.

• 1 and 3

• 1 and 4

• 2 and 3

• 2 and 4

Aqueous copper(Il) sulfate is electrolysed using carbon electrodes.

What is the product at each electrode?

• A

• B

• C

• D

An aqueous solution of copper(ll) sulfate was electrolysed using copper electrodes.

• A

• B

• C

• D

Electrolytes can be broken down by electrolysis

Which rows are correct for each electrolyte?

• 1 and 2

• 1 and 4

• 2 and 3

• 3 and 4

What are the ionic half-equations for the electrode reactions during the electrolysis of concentrated aqueous sodium chloride?

• A

• B

• C

• D

Concentrated aqueous copper(ll) chloride is electrolysed using copper electrodes as shown.

What happens to the mass of each electrode during this process?

• A

• B

• C

• D

Iron can be electroplated with zinc to make it resistant to corrosion.

Which row about electroplating iron with zinc is correct?

• A

• B

• C

• D

Which statement about the hydrogen fuel cell is not correct?

• Chemical energy is converted into electrical energy

• Hydrogen is oxidised.

• The reaction that takes place is endothermic

• Water is the only product