Understanding Electrolysis
Electrolysis means "splitting up with electricity," and it's actually pretty straightforward once you get the hang of it. You need an electrolyte (a liquid or solution containing ions) because the ions must be free to move around and carry electrical charge.
Here's the key thing to remember: ionic solids can't be electrolysed because their ions are stuck in fixed positions. But when you melt them or dissolve them in water, the ions become mobile and can carry charge around the circuit.
The setup involves two electrodes - a negative cathode and a positive anode - connected to a power supply. Positive ions (cations) always head to the negative cathode, whilst negative ions (anions) zoom towards the positive anode.
Quick Memory Trick: Remember "OIL RIG" - Oxidation Is Loss (of electrons), Reduction Is Gain (of electrons). This will save you in every chemistry exam!
At each electrode, specific reactions happen. Reduction (gaining electrons) occurs at the cathode, forming metals like lead from lead ions. Oxidation (losing electrons) happens at the anode, often producing gases like bromine or oxygen.