•3H2 + N2  2NH3
•3 mol of H2 reacts with 1 mol of N2 to form 2 mol of NH3
•3 molecules of H2 reacts with 1 molecule of N2 to form 2 molecules of NH3 
•6H + 2N reacts to give 6H and 2N
•6g of H2 reacts with 28 g of N2 to form 34g of NH3
•Note that