O-LevelChemistryStoichiometry5070/11 · May/June 2019 · Q121 Mark

The reaction for the conversion of bromoethane to ethanol is shown. C₂H₅Br + NaOH → C₂H₅OH + NaBr In an experiment, 10.90 g of bromoethane is converted into 3.45 g of ethanol. What is the percentage yield of ethanol? [Mr: C₂H₅Br, 109; C₂H₅OH, 46]

A32%

B42%

C75%

D100%

✓ Correct answer

C: 75%

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Topic: Stoichiometry, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, May/June 2019 Paper 1 Variant 1, question 12.

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