![volumetrix thermal expansion ideal gas volumetrix thermal expansion ideal gas](https://media.cheggcdn.com/media%2F055%2F055cd1f2-3486-4c48-815b-5d9aa5f31ee9%2FphpjO5waR.png)
![volumetrix thermal expansion ideal gas volumetrix thermal expansion ideal gas](https://s3.studylib.net/store/data/025222483_1-7d01ad4a1bf4d9a6a494f0d085eaa3eb-768x994.png)
If compression or expansion of gas takes place with no flow of heat energy either into or out of the gas - the process is said to be isentropic or adiabatic. Suffix 1 denotes initial conditions and suffix 2 denotes final conditions Isentropic (or adiabatic) Compression/Expansion Processes The isothermal process can also be expressed as The isothermal process can be expressed with the Ideal Gas Law as If compression or expansion of gas takes place under constant temperature conditions - the process is said to be isothermal. Isothermal Compression/Expansion Processes The relationship between pressure and density when compressing - or expanding - a gas depends on the nature of the process.