O-LevelChemistryStoichiometry5070/12 · Oct/Nov 2018 · Q111 Mark

A compound contains 40.0% carbon, 6.7% hydrogen and 53.3% oxygen by mass. The relative molecular mass of the compound is between 55 and 65. What is the molecular formula of the compound?

ACH2O

BC2H4O

CC2H4O2

DC2H6O2

✓ Correct answer

C: C2H4O2

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Topic: Stoichiometry, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, Oct/Nov 2018 Paper 1 Variant 2, question 11.

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