“Wonder Bottle” experiment
How to make liquid which turns to blue when shaken
Here’s an impressive magical experiment with a bottle! You can conduct this experiment at home with your friends!
Reagents and equipment:
- bottle with stopper;
- 10% sodium hydroxide solution;
- methylene blue solution;
Place the glucose in the bottle, then add the sodium hydroxide solution, and then the methylene blue solution. Mix together, shaking the bottle. The solution turns colorless. Shake the bottle again and the solution turns blue.
Methylene blue is an organic dye and indicator which easily reduces to a colorless state. As a reducer, glucose in an alkaline medium can be used. It reduces methylene blue to a colorless form. If you shake the bottle, the oxygen contained in the air oxidizes the colorless form back to a colored form. Then a reverse transformation to a colorless form takes place, until all of the glucose has oxidized to gluconic acid.
Be careful when working with diluted solution of sodium hydroxide. It is a corrosive substance which can cause burns to the skin and mucous membranes.