In order to implement the spirit of the internship in the opening ceremony of the opening ceremony of the first China International Import Expo, the Chairman of the Board of Directors of the People’s Republic of China, the State Council’s Customs Tariff Commission, reviewed and approved, and approve

1 acetylene white acetylene can not be near fire red2 hydrogen H2 light green hydrogen red red P=20, light yellow single ringP=30, light yellow double ring3 Oxygen O2 Light (酞) Blue Oxygen Black P=20, white single ring4 nitrogen N2 black nitrogen yellowish P=30, white double ring5 air black air whit

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 b

Temperature: macroscopically, the degree of heat and cold of an object; microscopically, a sign of the intensity of the irregular movement of molecules inside the object.The relationship between thermodynamic temperature and Celsius temperature: T = t + 273 {T: thermodynamic temperature (K), t: Cels