How to prove the existence of air, 6 ways to prove the existence of air

1 Weigh the mass of a closed container, sealed, weighed; The sealed air is then extracted in a sealed state and weighed again. There is a difference between the two weighings, which means that air is present. The amount of air pumped out is the difference between two weighings.

2 Look at the space Place an empty bottle upside down in the water, carefully open the cap, the water cannot fill the empty bottle, indicating that there is a certain volume of air present.

3 Measuring the pressure The atmospheric pressure can be measured by using the mercury column to be 760mmHg, and the existence of atmospheric pressure can be proved by using the Magdeburg hemispheric test Changing the sealing temperature, the change in pressure can be measured to prove the existence of air

4. Chemical reactions The presence of oxygen in the air can be proved using the combustion test.

5. Liquefaction By reducing the air temperature, different components of the air can be obtained at different low temperatures, such as liquid oxygen, liquid nitrogen, etc.

6 Why can you blow up balloons. Why do you feel resistance when you run into the wind?

7. Find an empty beer bottle, put the bottle mouth vertically facing down, and put it in the water until the water submerges the entire bottle, if the process is well controlled, there will be no bubbles coming out, and there will be no water entering (note that it should be vertical, if it is tilted, there will be bubbles), which means that the air is present so the water cannot enter.

Then slowly tilt the water bottle in the water, you will see bubbles coming out, and the water gradually enters the bottle, which is the air discharge, and the water enters the space that occupies the air.

Both processes in this test prove the presence of air.

When the fan rotates, the air blows out, and it is the flow of air.

Out. Breathe.

Turn the cup upside down and buckle it into the water, slightly diagonal, and bubbles will bubble.

Pump up your tires.

Inflate the balloons.

Cheer up the basketball.

Why can you blow up balloons. Why do you feel resistance when you run into the wind? Wait a minute.

The presence of air resistance proves the presence of air.

Turn the cup upside down and buckle it into the water, slightly diagonal, and bubbles will bubble.

This can be demonstrated with balloons.

6 Ways to Prove the Existence of Air::

1. Put the cup upside down in the water, and then let the regret crook the cup, and you can see bubbles coming out of the cup, which proves that the air is there.

2. Put the cup upside down in the water, the water cannot enter the cup, it proves that the air in the cup exists, and in the case of air, the water cannot enter the cup.

3. The rotation of the windmill can also feel the presence of the surrounding air.

4. Put the sponge into the water and squeeze it to produce bubbles to prove the existence of air.

5. Fill the sink with a beverage bottle and see bubbles bubble to prove the existence of air.

6. Today's aircraft are like *** and fixed-wing aircraft, and they can't fly without air.

Air is a mixture of gases in the Earth's atmosphere, which is composed of nitrogen, oxygen, noble gases (helium, neon, argon, krypton, xenon, radon), carbon dioxide, and other substances (such as water vapor, impurities, etc.). Among them, the volume fraction of nitrogen is about 78%, the volume fraction of oxygen is about 21%, the volume fraction of rare gases (helium, neon, argon, krypton, xenon, radon) is about, the volume fraction of carbon dioxide is about, and the volume fraction of other substances (such as water vapor, impurities, etc.) is about.

The composition ratio of air varies with altitude and air pressure. Historically, humans believed that air was a single substance, until the French scientist Lavoisier first came to the conclusion that air is composed of oxygen and nitrogen. At the end of the 19th century, scientists discovered through a large number of experiments that there were rare gases such as helium, argon, and xenon in the air.

If you put a bottle upside down in the water, the water will not flow into the bottle, and if you press the bottle downward, you will feel a resistance, which proves that there is air in the bottle.

Put the bricks, chalk, and put the bubbles in the water respectively, and put the bottle mouth into the water: there are no bubbles in the straight place, and there are bubbles in the oblique place.

Throw the plastic bag into the air and put the air into the bag, and then you can pinch, squeeze, and pat ......You can also feel the presence of air around you when you turn ...... windmill

For example, if you put a sponge in water and squeeze it to produce bubbles to prove the existence of air, use a plastic bag to capture the air, fan the air with your hand to prove the existence of air, take a bottle, fill it with water, and then put it upside down, the water will flow out, and then put in a piece of white phosphorus.

Close the lid, wait until the white phosphorus is natural, put the bottle into the water, and then release the lid, the water will enter, proving that the air in the bottle has entered, making the white phosphorus spontaneously combust, and it is proven!