1. There is gas tank, contains 5 liters of CO2 under pressure 14.7 MPa, temperatute is 300K. I try to calculate, what temperature gas will have after release (to atmospheric 0.1 MPa and 2000 liters volume). But I cannot :( 2. volume * pressure / temperature = const 3. The attempt at a solution To simplify, lets say it releases without any other expenses and all at once (ideal container without ability to transfer or store energy, no resistence from atmospheric air, etc). 5 liters *14.7 MPa /300Kelvin = 2000 liters *0.1 MPa /t2 73.5/300 = 200 /t2 0.245=200/t2 t2=816. Whoa! It become hot instead! Can anybody point me where I am wrong? Thank You.