In the reaction N2 + 3H2 → 2NH3, which of the following is the correct method to convert moles of N2 to moles of NH3?

• A. Multiply the moles of N2 by the ratio 2 mol NH3 / 1 mol N2
• B. Multiply the moles of N2 by the ratio 1 mol NH3 / 3 mol N2
• C. Multiply the moles of N2 by the ratio 3 mol NH3 / 1 mol N2
• D. Multiply the moles of N2 by the ratio 1 mol NH3 / 2 mol N2

Answer: (A)

Verified step by step guidance

1. Identify the balanced chemical equation: \(\mathrm{N_2 + 3H_2 \rightarrow 2NH_3}\).
2. Understand that mole ratios come directly from the coefficients in the balanced equation. Here, 1 mole of \(\mathrm{N_2}\) produces 2 moles of \(\mathrm{NH_3}\).
3. Set up the conversion factor as a ratio of moles of \(\mathrm{NH_3}\) to moles of \(\mathrm{N_2}\), which is \(\frac{2\ \mathrm{mol\ NH_3}}{1\ \mathrm{mol\ N_2}}\).
4. To convert moles of \(\mathrm{N_2}\) to moles of \(\mathrm{NH_3}\), multiply the given moles of \(\mathrm{N_2}\) by this ratio: \(\mathrm{moles\ of\ N_2} \times \frac{2\ \mathrm{mol\ NH_3}}{1\ \mathrm{mol\ N_2}}\).
5. This method ensures the units of \(\mathrm{N_2}\) cancel out, leaving the amount in moles of \(\mathrm{NH_3}\).