This question-specific review guide is tied to the answer reasoning for a PracticeTestVault item. Use it after you answer the question so the review stays focused on what the prompt actually tested.
What this question is testing
Objective: Apply stoichiometry to a limiting reactant problem
Prompt focus: For the reaction N2 plus 3 H2 yields 2 NH3, if 2 mol N2 react with 3 mol H2, which is the limiting reactant?
Why the correct answer works
H2
Only 3 mol H2 are available but 6 mol would be needed for 2 mol N2, so H2 is the limiting reactant.
Why the tempting wrong answer fails
The tempting wrong answer usually loses because it skips the key condition, priority, or evidence in the prompt.
Plain-language takeaway
The equation requires 3 mol H2 per 1 mol N2. With 2 mol N2 you would need 6 mol H2, but only 3 mol H2 are present, so H2 runs out first and limits the reaction.
Simple analogy
Think of apply stoichiometry to a limiting reactant problem like following a short checklist: identify the clue, confirm the rule, and then make the move that fits this exact scenario.
How to review it before a retake
- Underline the command word and name what the question is asking before rereading the choices.
- Compare the correct answer against the closest distractor and write the exact detail that separates them.
- Retest this objective with a fresh question without looking at the rationale first.