A container has two chambers of volumes \(\text{V}_1\,=\, 2\,\text{litres}\) and \(\text{V}_2\,=\, 3\,\text{litres}\) separated by a partition made of a thermal insulator. The chambers contain n1 = 5 and n2 = 4 moles of ideal gas at pressure p1 = 1 and p2 = 2 atm, respectively. When the partition is removed, the mixture attains equilibrium pressure of