Answer:
82.4 grams N₂(g)
Explanation:
3H₂(g) + N₂(g) => 2NH₃(g)
Assume excess H₂(g).
Convert gms NH₃ to moles, solve for moles of N₂ by rxn ratio then convert back to grams N₂(g).
Moles NH₃(g) = 100g/17g·mol⁻¹ = 5.882 mole NH₃(g)
Production of 5.882 mole NH₃(g) requires 1/2(5.882) mole N₂(g) = 2.9941 mole N₂(g)
Grams N₂(g) needed = 2.9941 mole N₂(g) x 28 gms/mole = 82.4 gms N₂(g).