Final answer:
Upon the completion of the reaction of nitrogen gas with hydrogen gas to produce ammonia, starting with 12 moles of nitrogen and 24 moles of hydrogen, 24 moles of ammonia would be produced.
Step-by-step explanation:
The production of ammonia from nitrogen gas (N2) and hydrogen gas (H2) is described by the balanced chemical equation N2 + 3 H2 → 2 NH3. Starting with 12 moles of nitrogen gas and 24 moles of hydrogen gas, and knowing that one mole of nitrogen reacts with three moles of hydrogen to produce two moles of ammonia, we can determine the amount of ammonia produced at completion of the reaction.
Since nitrogen is the limiting reactant, we can directly use its amount to calculate the ammonia produced. The stoichiometry of the reaction is such that for every mole of nitrogen, two moles of ammonia are produced. Therefore, for 12 moles of nitrogen, the number of moles of ammonia produced will be 2 × 12 = 24 moles of ammonia.