Ideal gas going though an adiabatic process

Adiabatic process is a process in which there is no heat exchange between the surrounding and the gas.

So for example if an expansion happens really fast this process is adiabatic because there is no time for the heat to get transfered.

My professor said that we can describe this situation with ideal gas laws. But how can you do that while ideal gas law only hold in equilibrium states and if the process happens very fast there is no enough time for the pressure to become equilibrium pressure?

What we can calculate is if we make a box that is completely isolated and lower the pressure slowly.

• how can you do that while ideal gas law only hold in equilibrium states I think you are jumping ahead of yourself a bit here en.wikipedia.org/wiki/Ideal_gas_law. Have a read of this as to the characteristics needed to fulfill the ideal gas law.
– user176049
Commented Nov 25, 2017 at 18:38
• The ideal gas law applies at the initial and final thermodynamic equilibrium states. Commented Nov 25, 2017 at 19:05
• Yes but in between we can for example find the work done as we do in other processes Commented Nov 25, 2017 at 19:13