The main components in the air are nitrogen, oxygen, rare gases, carbon dioxide and other substances (such as water vapor, impurities, etc.).
Air is a mixture, and its composition is very complex, which is mainly the result of mutual compensation of various changes in nature. The variable components of air are carbon dioxide and water vapor.
The indefinite composition of the air varies completely from region to region. For example, the air near the factory area will contain ammonia, acid vapor, etc. due to different production projects. In addition, the air also contains very small amounts of hydrogen, ozone, nitrogen oxides, methane and other gases. Dust is more or less suspended impurities in the air.
In general, the composition of air is generally fixed. This is very important for the survival of human beings and other animals and plants. However, with the development of modern industry, the harmful gases and soot discharged into the air have changed the composition of the air and caused air pollution. The polluted air will seriously damage human health, affect the growth of crops, and cause damage to natural resources and buildings.