Chemistry · Stoichiometry
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lf 28.0g nitrogen gas is reacted with 8.0g of hydrogen gas to form Ammonia, the limiting reactant among the two will be:
- A
N2
- B
H2
- C
Both a & b
- D
None of them
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.
Tagged under Chemistry · Stoichiometry · 2008