Experiment How to make Hydrogen bubble

Experiment How to make Hydrogen bubble

Concept
The hydrogen gas is lighter than the air. Let's experiment it by using soap bubbles.

Materials
PET bottle, straw, clay, zinc, diluted hydrochloric acid, glass, and the liquid detergent

Procedure

1. The small hole is made in the cap of the PET  bottle. The straw is passed through the cap. Surrounding of the hole is sealed with clay.
2. The liquid detergent is thinned to 20 times by water and the soap bubble liquid is
   made.
3. Zinc and diluted hydrochloric acid are put in the PET bottle and the cap is done.
4. The straw end is put into the soap liquid. Soap bubbles swell, and these rise in the air.