Theoretical yield of iron from haematite (Fe₂O₃)

Steps:

• Haematite formula is Fe₂O₃; molar mass ≈160 g/mol (Fe: 112 g/mol, O: 48 g/mol).
• Reaction yields 2 mol Fe (112 g) from 1 mol Fe₂O₃ (160 g).
• Mass fraction of Fe: 112/160 = 0.7.
• Maximum iron from 500 kg haematite: 500 × 0.7 = 350 kg.

Why C is correct:

• 350 kg equals the stoichiometric mass of Fe in 500 kg Fe₂O₃, per conservation of mass in balanced equation Fe₂O₃ → 2Fe + (3/2)O₂.

Why the others are wrong:

• A: Underestimates by ignoring full Fe content, perhaps confusing with oxygen mass.
• B: Assumes partial yield, like 48% efficiency instead of 70%.
• D: Overestimates, exceeding total mass of haematite.

Final answer: C