GCSE Chemistry Electrolysis required practical explained.

Aim

To identify products made at the electrodes during electrolysis of aqueous copper chloride.

Method students should know

1. Pour copper chloride solution into a beaker.
2. Place graphite electrodes into the solution without touching.
3. Connect electrodes to a low-voltage DC supply.
4. Turn on the power and observe each electrode.
5. Test gas at the positive electrode using damp blue litmus paper.

Variables

Independent variable

Solution being electrolysed.

Dependent variable

Products formed at each electrode.

Control variables

Voltage, Electrode material, Volume and concentration of solution

Safety and common mistakes

• Wear eye protection.
• Use low voltage.
• Chlorine is toxic, so use small quantities in a ventilated room.
• Confusing cathode and anode charges.
• Writing atoms move instead of ions move.
• Forgetting state symbols in half equations.