🟤 Halogen displacement: virtual chemistry experiment
Chlorine water releases iodine from iodide; starch shows it as blue-black.
▶ 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 5 mL chlorine water to the KI tube (turns brown)
- Add chlorine water to the NaBr tube (turns orange)
- Add starch to the KI tube: blue-black
The chemistry behind it
Cl₂ + 2I⁻ → 2Cl⁻ + I₂. A more reactive halogen displaces a less reactive one from its salts.
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 halogen displacement experiment?
1. Add 5 mL chlorine water to the KI tube (turns brown) 2. Add chlorine water to the NaBr tube (turns orange) 3. Add starch to the KI tube: blue-black You can run every step free in the Faradium virtual chemistry lab.
What is the chemistry behind halogen displacement?
Cl₂ + 2I⁻ → 2Cl⁻ + I₂. A more reactive halogen displaces a less reactive one from its salts.
Can I do the halogen displacement 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: Chlorine (Cl), Iodine (I).
Molar masses you may need: H2O.
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