“Iodine flower” experiment
How to color a paper flower without touching it
How can you color a flower with air?
Wear protective gloves, a mask and glasses, and work in a well-ventilated room.
Warning! Only under adults supervision.
Reagents and equipment:
- 10% starch solution (50 ml);
- 10% iodine solution in potassium iodide (5 ml);
- paper napkin;
- wooden stick;
- scotch tape;
- glass dome;
Make a flower from a paper napkin, attach it to the stick with scotch tape and coat the petals with the starch solution. Pour the iodine solution in the potassium iodide into the glass, put the starched flower in the glass and cover with a glass dome. After a few seconds the flower will turn blue.
Iodine has high volatility, and at room temperature it evaporates from the potassium iodide solution. The iodine vapors react with the starch on the flower petals and form a blue starch-iodine complex.