The equilibrium constant for the reaction, 3 H₂(g) + N₂(g) ⇄ 2 NH₃(g), at a given temperature is 1.4 × 10^–7. Calculate the equilibrium concentration of ammonia, if [H₂] = 1.2 × 10^–2 mol L^–1 and [N₂] = 3.2 × 10^–3 mol L^–1.