🐘 Elephant's toothpaste: virtual chemistry experiment
Iodide-catalysed decomposition of 30% hydrogen peroxide produces a towering, steaming foam.
▶ 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
- Add 10 mL of potassium iodide solution
- Watch the foam erupt; the reaction is strongly exothermic
- Test the gas with a glowing splint
The chemistry behind it
2H₂O₂ → 2H₂O + O₂, catalysed by I⁻ (H₂O₂ + I⁻ → H₂O + IO⁻, then H₂O₂ + IO⁻ → H₂O + O₂ + I⁻). The detergent traps the oxygen as foam.
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 elephant's toothpaste experiment?
1. Add 10 mL of potassium iodide solution 2. Watch the foam erupt; the reaction is strongly exothermic 3. Test the gas with a glowing splint You can run every step free in the Faradium virtual chemistry lab.
What is the chemistry behind elephant's toothpaste?
2H₂O₂ → 2H₂O + O₂, catalysed by I⁻ (H₂O₂ + I⁻ → H₂O + IO⁻, then H₂O₂ + IO⁻ → H₂O + O₂ + I⁻). The detergent traps the oxygen as foam.
Can I do the elephant's toothpaste 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), Iodine (I).
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🫧 CO₂ and limewater
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