N moles of Ar and 2n moles of Xe (treated as ideal gases) are in adjacent containers with volumes of V and 2V, respectively. The barrier between the two gases is removed, and the two gases mix. Heat and work are not exchanged with the surroundings. Since the two gases start at the same temperature and pressure, the temperature and pressure must not change during mixing. What are delta U, delta H, and delta S for the system after it reaches equilibrium What is the entropy change of the universe after the system reaches equilibrium Is the process spontaneous?