Air definition and characteristics are important

Air components: -
A small and unstable amount of water vapor
Inert gases such as argon 97.%
Nitrogen 78%
  Oxygen 21%
  CO 3%
 Inert gases such as argon 97.%
A small and unstable amount of water vapor

We have the air everywhere in the caves and the gaps between the rocks and the soil piles, as well as being dissolved in the rivers and seas, and the lack of feeling of air around you or the lack of wind does not mean that the air does not exist; it can not be felt because it is light but always exists The feeling sometimes when the air is silent that does not exist, but this is known wrong, the air exists all the time, even if it is silent.

One of the most important elements of life is the air. There is no air. There is no life where breathing depends on all kinds of organisms. If it is lost for any reason, it will kill life on the planet.

The importance of air: -
The life of any organism on the earth without air is not a major element in order to continue life, where it is important in the process of breathing for all living things. And generating electricity from windmills. As well as photosynthesis of plants.

Characteristics of air: -
Moves from high to low pressure.
The air does not conduct electricity, it is an electrical insulator.

For air, a block: When a ball is filled with air on the assumption that it may weigh 400 grams. When weighing the same balloon, but without air, it may weigh 370 grams, and we conclude that the air has a mass in which the air is measured.
Air mass: -
The air mass and measured the mass of air according to the space that it contains.

It shrinks with a reduced temperature and expands with an increase in temperature.
The weight of hot air is less than the weight of cold air.
Air is a group of gases with no color, no taste, no smell.
When we grasp the opening of the needle and we press the needle button, we find that the air inside the pressure and the process of drawing the needle, the air expands and this proves that the airs can be compressed and also through this experience prove that the air can expand and press at the same time.
The air is formed in the form of the vessel or vessel inside it. The air has no shape
 For example, if we blow a balloon in the air it takes the shape of the space contained in the balloon, sometimes the air is different shapes may be cylindrical or circular, depending on the shape contained in the air.