Transfer of Charge During Electrolysis
Chemistry: Cambridge International GCSE Supplement, topic 4.1.5
Transfer of Charge During Electrolysis
Electrolysis transfers charge through electron flow in circuits, electron gain/loss at electrodes, and ion movement in the electrolyte, driven by an external power supply.
Movement of electrons in the external circuit
- Electrolysis uses an external power supply to drive a reaction.
- Electrons flow from the negative terminal to the cathode in the circuit.
- Electrons return to the positive terminal after leaving the anode.
- This electron flow in the external circuit carries charge during electrolysis.
Loss or gain of electrons at electrodes
- At the cathode, positive ions gain electrons (reduction).
- At the anode, negative ions lose electrons (oxidation).
- Electron gain or loss changes ions into atoms or molecules.
- These electron transfers produce new substances at electrodes.
Movement of ions in the electrolyte
- Positive ions move towards the cathode to gain electrons.
- Negative ions move towards the anode to lose electrons.
- Ion movement inside the electrolyte completes the electrical circuit.
- This ion flow balances charge as electrons move in the external circuit.
Summary of charge transfer in electrolysis
- Electrons move through the external circuit from anode to cathode.
- Electrodes show electron loss (anode) or gain (cathode) during reactions.
- Ions move within the electrolyte to balance charge transfer.
- This combined movement allows electrolysis to produce chemical changes.
Test yourself on Transfer of Charge During Electrolysis
What happens to negative ions at the anode during electrolysis?
What completes the electrical circuit inside the electrolyte during electrolysis?