If you use 45 grams of hydrogen, how many moles of ammonia can you make?

Question

Use the equation :

N₂ (g) + 3 H₂ (g) → 2 NH₃ (g)

Answer 1

45 grams of H₂ (hydrogen gas)

The molar mass of H₂ is 2(1.01) = 2.02 grams.

45 g H₂ × (1 mol H₂ / 2.02 g H₂) × (2 mol NH₃ / 3 mol H₂) = 15 mol NH₃

I set up the picket fence to find the number of moles of ammonia. Multiply the molar mass of hydrogen gas by the conversion factor (1 mole of H₂ = 2.02 g of H₂). Multiply that by the mole ratio of 2 moles of ammonia to 3 moles of hydrogen gas. Therefore, there are about 15 moles of ammonia by using significant figures.