Acetylene, is an organic compound, chemical expression is C2H2, commonly known as wind coal or calcium carbide gas, is the smallest alkyne compound in volume, room temperature and pressure for a colorless gas, slightly soluble in water, soluble in ethanol, acetone, chloroform, benzene, mixed in ether, is one of the important raw materials for organic synthesis, but also synthetic rubber, synthetic fiber and plastic monomer, can also be used for oxygen acetylene welding.

Compressed gas refers to the gas that is completely gaseous when pressurized at -50℃, including the gas whose critical temperature is lower than or equal to -50℃.
Liquefied gas refers to the gas that is partially liquid due to low temperature during transportation (the critical temperature is generally lower than or equal to -50℃).

Hydrogen bromide gas is a chemical compound with the chemical formula HBr. It is a colorless, pungent odor gas with high corrosion and toxicity.

The Common Technical Term for Gases