Consider a rigid piston cylinder arrangement. Assume that the cylinder and the piston are covered by a perfectly insulating material and the piston cylinder interface is very smooth. Two types of ideal gases are separated in the cylinder by the piston. The number of gas molecules of type A is equal to N and the number of gas molecules of type B is twice as that of A. At thermal equilibrium, one finds that the volume occupied by each of gases is the same and equal to V. the temperature of the gas is T, and the temperature of the gas A is twice that of gas B. After a certain time, a door in the piston is slowly opened and the gases are allowed to mix. Find the pressure, after mixing is complete.
PV = N KbT