FIGURE 6.8A mixture of NH3(g), N2(g), and H2(g) at equilibrium. (b) The volume is suddenly decreased. (c) The new equilibrium position for the system containing more NH3, less N2, and less H2. The reaction N2(g) + 3H2(g) 2NH3(g) shift to the right (toward the side with fewer molecules) when the container volume is decreased. .