Chemistry · Stoichiometry

The balanced chemical equation for the formation of ammonia (NH₃) is:

N₂ + 3H₂ → 2NH₃

You start with 28.0 g of N₂ and 8.0 g of H₂. The molar mass of N₂ is 28.0 g/mol, so you have 1 mole of N₂. The molar mass of H₂ is 2.0 g/mol, so you have 4 moles of H₂.

According to the balanced equation, 1 mole of N₂ requires 3 moles of H₂ to fully react. Since you have only 1 mole of N₂ and 4 moles of H₂, N₂ will run out first, making it the limiting reactant. Therefore, the correct answer is Option A: N₂.

Option B is incorrect because there is excess H₂ present. Option C is incorrect because only one reactant can be limiting. Option D is incorrect because there must be a limiting reactant in this scenario.

Nitrogen gas is the limiting reactant because it has fewer moles compared to the amount needed to fully react with hydrogen gas based on the stoichiometric ratio.

Hydrogen gas is not the limiting reactant because it has more moles available than required to react with nitrogen gas.

Both cannot be limiting reactants as there must be one reactant that runs out first, preventing the reaction from continuing.

One of the reactants must be limiting in a chemical reaction where the reactants are not in exact stoichiometric proportions.