Say I have a box of volume $V$, with an ideal gas inside it with temperature $T_b$. I don't know the number of particles inside it. The box is surrounded by the room's environment, which has essentially infinite volume, the same kind of ideal gas, but a different temperature $T_a$, and atmospheric pressure $P_a = 1\text{atm}$.
Is it possible to calculate the pressure $P_b$ the box's walls experience? I'm also interested in how to describe the change in $P_b$ as heat is transferred from the box to the environment, and the temperatures equalize, if that is possible to calculate.
I tried to solve this with the $P V = N K_B T$ formula but it is weird how to treat the environment with it's infinite volume.