If you have 5 mol H2 and 2 mol N2, what is the limiting reagent in the reaction below?
3 H2(g) + N2 (g) → 2 NH3 (g)

Hydrogen is the limiting reactant.

Explanation:

Hello!

In this case, for the identification of the limiting reactant, it is necessary to compute the yielded moles of ammonia via both hydrogen and nitrogen in agreement to the 3:2 and 1:2 mole ratios respectively:

Thus, since hydrogen yields the fewest moles of ammonia we infer it is the limiting reactant.

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