🍷 Breathalyser: virtual chemistry experiment
Acidified dichromate turns from orange to green with ethanol.
▶ 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 2 mL of ethanol
- Warm gently with the spirit burner; watch orange → green
The chemistry behind it
Cr₂O₇²⁻ + 3C₂H₅OH + 8H⁺ → 2Cr³⁺ + 3CH₃CHO + 7H₂O. Cr(VI) (orange) is reduced to Cr(III) (green).
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 breathalyser experiment?
1. Add 2 mL of ethanol 2. Warm gently with the spirit burner; watch orange → green You can run every step free in the Faradium virtual chemistry lab.
What is the chemistry behind breathalyser?
Cr₂O₇²⁻ + 3C₂H₅OH + 8H⁺ → 2Cr³⁺ + 3CH₃CHO + 7H₂O. Cr(VI) (orange) is reduced to Cr(III) (green).
Can I do the breathalyser 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: Oxygen (O), Chromium (Cr).
Molar masses you may need: C2H5OH.
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