Various gases in the air

The nitrogen content in the air is the most, and nitrogen is mainly used for ammonia synthesis, and is also an important raw material for synthetic fibers, synthetic resins, and synthetic rubber. Nitrogen can be used as a preservative, refrigerant, and can also be used to make fertilizers.

Followed by oxygen, oxygen has a very wide range of uses. Mainly to supply breathing, support combustion and reaction heat release three aspects:

1. Supply breathing: Under normal circumstances, breathing only needs air. However, in an oxygen-deficient, hypoxic or anaerobic environment, such as diving operations, mountaineering, high-altitude flights, space navigation, medical rescue, etc., oxygen is often required.

2. Support combustion: Under normal circumstances, only air is required for combustion. However, in some special requirements such as high temperature and rapid combustion, such as blast iron making, converter steel making, etc., oxygen-enriched air or oxygen is required.

3. Exothermic reaction: When an oxidation reaction, especially a combustion reaction, is carried out, a large amount of heat released can be utilized. For example, coal heating, thermal power generation; industrial use of acetylene gas generated by the combustion of acetylene in oxygen to weld or cut metal, oxyacetylene flame can produce high temperatures above 3000 °C.

People also use liquid oxygen to impregnate porous materials such as wood chips and charcoal powder to make liquid oxygen explosives, which are used for open-pit engineering blasting such as mountain rocking and trench mining. In addition, oxygen (air) is also a raw material for the production of chemical products such as sulfuric acid and nitric acid.

Carbon dioxide can extinguish fire, produce soda, promote plant photosynthesis (for gas fertilizer); for alkali industry, sugar industry, and for quenching and lead white manufacturing of steel castings, etc.

Rare gases such as helium, neon, argon, xenon, krypton, xenon, etc. can be filled in the bulb for the manufacture of electric light sources for various purposes.