Given that you have 14.5 moles of N2, how many moles of H2 are need to produce 22.5 moles of NH3 according to the reaction: N2+ 3 H2 yields 2...

The balanced reaction is :-

N2(g) + 3H2(g)  ---------->  2NH3(g)

In the above balanced reaction, N2 and H2 reacts in the molar ratio of 1:3.

Thus, for each mole of N2, 3 moles of H2 is required for complete reaction.

Now, moles of N2 present = 14.5

Thus, for complete reaction of N2, moles of H2 required = 3*moles of N2 = 3*14.5 = 43.5 moles

Now, moles of NH3 formed after complete reaction = 2*moles of N2 reacting = (2/3)*moles of H2 reacting = 2*14.5 = 29

Now, clearly, we don't want complete reaction to occur.

The moles of NH3 required to be produced = 22.5

Thus, moles of H2 required = (3/2)*moles of NH3 formed = 33.75 moles

Hence moles of N2 actually reacting = (1/2)*moles of NH3 formed = 22.5/2 = 11.25

Thus, N2 left unreacted = 14.5 - 11.25 = 3.25 moles