Careful, the ideal gas law doesn’t really tell you this at all. The nice case is adiabatic expansion, and at least the sign of the temperature change has the d

Careful, the ideal gas law doesn’t really tell you this at all. The nice case is adiabatic expansion, and at least the sign of the temperature change has the decency to behave the way one would expect: https://en.m.wikipedia.org/wiki/Adiabatic_process https://en.m.wikipedia.org/wiki/Adiabatic_process The more realistic case for a gas station is Joule-Thomson expansion, and it thoroughly defies basic intuition: https://en.m.wikipedia.org/wiki/Joule%E2%80%93Thomson_effect https://en.m.wikipedia.org/wiki/Joule%E2%80%93Thomson_effect