Imagine I have 2 constant-volume, constant-temperature containers. Container A has a volume of 10 L and one Container B has a volume of 5 L. My hypothetical gases Ideal Gas A and Ideal Gas B have the same properties as each other (temperature, mass, energy, heat capacity, blah blah blah). If I insert 3 moles of Ideal Gas A and 3 moles of Ideal Gas B into Container A and connect the two containers, I'd expect the pressure to equalize between the containers, and the final distribution of the gases to be Container A: 2 moles Gas A, 2 moles Gas B Container B: 1 mole Gas A, 1 mole Gas B makes sense. Now, I restart the experiment, but this time I've placed a magic filter (possibly controlled by a demon) that only allows Gas B to pass, and insert it the connection between the two containers. What would the distribution of the gases be? Obviously all of Gas A stays in Container A, thanks to the filter. Would Gas B move to Container B until the total pressure was equal between the two containers? Or would the partial pressure of Gas B move it until the Gas B pressure was equal. Or does it have to do with the number of moles in each container. Or....? Thanks for any insight anyone who understands ideal gas laws can give!