Labs / Chemistry
Electrolysis
Wire a battery to two electrodes dipped in an electrolyte and force a reaction that would never happen on its own. Positive ions crowd toward the negative cathode and negative ions toward the anode, where they gain or lose electrons — and the readouts count the gas volume or metal mass exactly as Faraday's laws predict.
t 0 sQ 0 Ccathode —anode —
What to try
- Turn the voltage down slowly. Why does everything stop at a certain point, even though the current dial hasn't moved?
- In the water cell, count the bubbles at each electrode. Why does the cathode make roughly twice as much gas as the anode?
- Double the current. Does the metal plate out twice as fast, and does the charge Q climb at twice the rate?
- Switch to copper sulfate. Where does the dissolved copper go, and what builds up on the cathode over time?
- For the same charge Q, which electrolyte deposits more mass or releases more gas — and what in Faraday's law decides that?