Since there is excess hydrogen, that means that the concentration of hydrogen is not limiting.
According to the balanced chemical equation:
every mole of N2 and every 3 moles of H2 we obtain 2 moles of NH3. Since we have the amount of N2 and excess of hydrogen, we only need to work with the amount of N2.
1 mol of N2 will produce 2 moles of NH3
so now we can get a conversation tool :
moles of N2 * (2 moles of NH3/ 1 mole of N2) = moles of NH3
(2.22 mol of N2 x 2) ÷ 1 = 4.44 mol of NH3