⚡ Electrolysis of water: virtual chemistry experiment
Split water in a Hofmann voltameter: twice as much hydrogen as oxygen.
▶ Launch this experiment freeRuns in your browser on any phone, tablet or laptop. No sign-up, no install, no chemicals needed.
What you'll do
- Switch the power supply on
- Watch the gas volumes: cathode (−) collects twice as much
- Test the cathode gas (squeaky pop) and the anode gas (relights splint)
The chemistry behind it
2H₂O → 2H₂ + O₂. Sodium sulfate only makes the water conduct. Four electrons give two H₂ but only one O₂, so the volumes are 2:1.
Why do this experiment virtually?
Many school labs can't run this experiment safely or don't have the chemicals. In Faradium you set it up in seconds, repeat it as often as you like, change the amounts and see the real result: colours, gases, precipitates and temperature changes. The lab notebook records every observation with the balanced equation for your write-up.
Frequently asked questions
How do you do the electrolysis of water experiment?
1. Switch the power supply on 2. Watch the gas volumes: cathode (−) collects twice as much 3. Test the cathode gas (squeaky pop) and the anode gas (relights splint) You can run every step free in the Faradium virtual chemistry lab.
What is the chemistry behind electrolysis of water?
2H₂O → 2H₂ + O₂. Sodium sulfate only makes the water conduct. Four electrons give two H₂ but only one O₂, so the volumes are 2:1.
Can I do the electrolysis of water experiment online for free?
Yes. Faradium sets up the bench for you and ticks off each step as you complete it. It runs in any browser on a phone, tablet or laptop with no sign-up and no chemicals.
Chemistry in this experiment
Elements involved: Hydrogen (H), Oxygen (O).
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