N2+3H2=2NH3

Question

Assume 0.150 mol of N2 and 0.477 mol of H2 are present initially. After complete reaction, how many moles of ammonia are produced?

Answer 1

This is a limiting reagent problem. I work these the long way. First we determine which is the limiting reagent.
How much NH3 can be produced with 0.150 mol N2 and all the H2 needed?
0.150 mol N2 x (2 mol NH3/1 mol N2) = ?

How much NH3 can be produced with 0477 mol H2 and all the N2 needed?
0.477 mol H2 x (2 mol NH3/3 mol H2) = ?

You obtain two different answers; the correct answer in limiting reagent problems is ALWAYS the smaller number and the reagent producing that value is the limiting reagent.