How to make a flying balloon?

The method of making flying balloons is as follows:

Method one

1, cut 5 cm long from a long straw. Half the cut straw is inserted into the opening of the balloon.

2. Fasten the straw firmly at the opening of the balloon with plastic tape. Because the air is blown into the balloon through a straw, it must be wrapped with tape to ensure that there is no gap.

3. Inflate the balloon with a straw. Then take the balloon out of your mouth, press the opening of the straw with your fingers to prevent the gas in the balloon from escaping, and then suddenly release your hand.

Balloons run around the room instantly, and each flight mode is different, which is very interesting. Try one yourself.

Method 2

Make a pocket similar to a hot air balloon with fine cloth or soft paper, except that the mouth cannot leak. Tie several edges of the pocket with a string, and then tie a small basket similar to a hot air balloon at the other end of the rope. Pay attention to the uniform balance and the length of the rope should be the same. Put a small candle on the basket to support your pocket so that it won't burn. Then you can light the candle and let go when the hot air fills your pocket.

Balloons fly because the gas in the balloon is lighter than air, but the gas exhaled by our population contains more carbon dioxide, so it is denser than air, so the blowing mouth must be heavy.

A balloon inflated by an ordinary air pump can float gently or fall, but it won't fly, because the gas in the balloon is the same as the air. Balloons can fly by introducing a gas that is less dense than air, and try to use a gas that is much less dense than air.

The first thing that comes to mind is hydrogen, which is cheap. It is sold in many places and can be bought online, but one thing is that hydrogen is a combustible gas and has potential safety hazards. Helium is a better gas, but inert gas is very safe. The inflation step is very simple, and there are instructions after buying the inflation equipment.

Take a glass bottle with a rubber stopper and insert a glass tube. Put zinc granules into a bottle, pour in a proper amount of dilute hydrochloric acid, plug the cork, and put the balloon mouth on the glass tube at the bottle mouth. Soon, you can see that the balloon is full of hydrogen produced in the bottle. Take the balloon with enough hydrogen off the bottle mouth and tie the balloon mouth with thread. Once you let go, the balloon will fly into the sky under the buoyancy of the air.