“Iodine camera“ from the “Chemistry for detectives“ set
Channel: MEL Chemistry
Date: 18/04/2018

Perform this amazing experiment at home with MEL Science: https://melscience.com/en/experiments/iodine-chamber/

Safety
* Put on protective gloves and eyewear.
* Conduct the experiment on the plastic tray.

Disposal
* Add a couple of spoons of Na₂S₂O₃ to neutralize the iodine solution.
* Pour the solution down the sink.
* Wash away with an excess of water.

Step-by-step instructions

1. Prepare 3% solution of hydrogen peroxide H₂O₂.
2. Measure 1 big spoon of 5% potassium iodide KI solution into the plastic cup.
3. Add there 1 big spoon of 1М citric acid solution.
4. Pour 3 big spoons of 3% solution of hydrogen peroxide H₂O₂.
5. Carefully swirl the cup to mix the contents.
6. Take off one protective glove and leave a fingerprint on a white sheet of paper.
7. Cover the cup with the sheet of paper with the fingerprint. Wait 5 min.
8. Iodine reveals the fingerprint!