The equilibrium constant for the following reaction is 3.0: N2(g) + 3 H2(g) = 2 NH3(g)

Enough NH3 was added to a 5.0 L container such that at equilibrium, the container was
found to contain 2.5 mol of N2. How many moles of NH3 were put into the container? Solve using the ICE table.