Liquid gas is a special state of matter that combines some properties of gas and liquid. At a certain temperature and pressure, gas can be transformed into liquid state, and this transformation is called condensation of gas. Liquid gas has fluidity and can flow to any part of the container. At the same time, it is incompressible, and its volume remains almost unchanged even under high pressure. In addition, liquid gas can also evaporate into gas under certain conditions.

Common liquid gases include liquid nitrogen (LN2), liquid oxygen (LOX), liquid argon (LAr), liquid helium (LHe), liquid hydrogen (LH2), etc. These liquid gases have a wide range of applications in their respective fields, such as refrigeration, cryogenic experiments, aerospace, nuclear physics experiments, semiconductor manufacturing, superconducting material research, etc.

Please note that liquid gas needs to be used with special care, because some liquid gases may evaporate rapidly at normal temperature and pressure, resulting in a sharp increase in pressure and even explosion. In addition, some liquid gases are toxic or corrosive, so corresponding safety operating procedures need to be followed when using and storing them.