noun
real gas
Technical term in physics and chemistry, contrasted with 理想気体 (ideal gas). Used when gas behavior deviates from the ideal gas law.
See also: 理想気体
実在気体は、高圧下では理想気体の法則から外れる。
Real gases deviate from the ideal gas law under high pressure.
理想気体 is an idealized model that perfectly follows PV=nRT, while 実在気体 refers to actual gases with intermolecular forces and volume.
Compound of 実在 (actual existence) and 気体 (gas). The term is a direct conceptual translation of the English 'real gas'.