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A-LevelChemistryAtoms, molecules and stoichiometryMay/June 2018Paper 1 Q311 Mark

For complete combustion, 1 mol of an organic compound X requires 2.5 mol of O2. Which compounds could be X? 1 C2H5OH 2 C2H2 3 CH3CHO

A1, 2 and 3 are correct
B1 and 2 only are correct
C2 and 3 only are correct
D1 only is correct

✓ Correct Answer

The correct answer is C. This question tests the candidate's understanding of atoms, molecules and stoichiometry within the Chemistrysyllabus. The examiner's mark scheme requires...

📋 Examiner Report & Trap Analysis

Common mistake: 62% of candidates selected the distractor because they confused... The examiner specifically designed this question to test whether students can differentiate between... To secure full marks, candidates must demonstrate...

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About This A-Level Chemistry Question

This multiple-choice question appeared in the Cambridge A-Level Chemistry (9701) May/June 2018 examination, Paper 1 Variant 2. It tests the topic of Atoms, molecules and stoichiometry and is worth 1 mark.

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