What is Electrolysis?
Electrolysis is the process of using electricity to break down (decompose) a compound, usually an ionic compound in molten state or in aqueous solution.
This process takes place in an electrolytic cell.
Parts of an electrolytic cell:
Battery (Power Source)
- Draws electrons away from anode.
- Electrons enter the positive terminal of battery and leave from the negative terminal.
- Electrons are supplied to the cathode, which becomes negatively charged.
Electrolyte
- An electrolyte is a molten ionic compound or an aqueous solution that can be decomposed by an electric current to form cations and anions.
- Contains mobile ions, hence allow electricity to flow through.
- Substances that do not conduct electricity under any condition are called non-electrolyte.
- Example: Sulfur, sugar, distilled water, organic compounds.
Electrodes
- Conduct electricity into and out of the electrolyte.
- Anode: The electrode connected to the positive terminal of the battery.
- Cathode: The electrode connected to the negative terminal of the battery.
- Common materials: Carbon (graphite) rods or metal plates.
- Inert electrodes (e.g. platinum, graphite) do not react and do not affect the products formed.
Key Summary
- Anode → Positive electrode (oxidation occurs here)
- Cathode → Negative electrode (reduction occurs here)
- Electricity flows because of the movement of ions in the electrolyte.
Science with Tara 