In the reaction N_2 + 3H_2 → 2NH_3, how many hydrogen molecules (H_2) are required to completely react with 10 nitrogen molecules (N_2)?

• A. 30
• B. 20
• C. 5
• D. 10

Answer: (A)

Verified step by step guidance

1. Identify the balanced chemical equation: \(\mathrm{N_2 + 3H_2 \rightarrow 2NH_3}\).
2. From the equation, note the mole ratio between nitrogen molecules (\(\mathrm{N_2}\)) and hydrogen molecules (\(\mathrm{H_2}\)) is 1:3, meaning 1 mole of \(\mathrm{N_2}\) reacts with 3 moles of \(\mathrm{H_2}\).
3. Given 10 molecules of \(\mathrm{N_2}\), multiply this amount by the mole ratio of hydrogen to nitrogen to find the required hydrogen molecules: \$10 \times 3$.
4. Calculate the total number of hydrogen molecules needed to completely react with 10 nitrogen molecules.
5. Express the final answer as the number of hydrogen molecules required.