O-LevelChemistryStoichiometry5070/12 · Oct/Nov 2020 · Q171 Mark

The equation shows the production of iron by the reduction of iron(III) oxide. Fe2O3 + 3CO → 2Fe + 3CO2 80 tonnes of iron(III) oxide produces 50 tonnes of iron. What is the percentage yield?

A45%

B63%

C68%

D89%

✓ Correct answer

D: 89%

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Topic: Stoichiometry, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, Oct/Nov 2020 Paper 1 Variant 2, question 17.

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