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Chemical traffic light

Green, red, yellow — and green again when you shake it.

Topic: Organic chemistryGrade: 10Free

🧪 Start the experiment — free

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What you do

  1. Add indigo carmine to the alkaline glucose solution and watch.
  2. Wait until it turns yellow (speed ×5 helps).
  3. Press “Shake”. Why does it turn green again?

Safety in a real lab

⚠ Sodium hydroxide is corrosive: goggles and gloves.

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