0654.C3.1.02 — Define the molecular formula of a compound as the number and type of atoms in one molecule: past paper questions

Real questions on 0654.c3.1.02 — define the molecular formula of a compound as the number and type of atoms in one molecule

The newest 5 of 5 written questions. Open one to see it on the real paper.

1. 0654/32 · May/June 2026 · Q7a(i)[1]

   Determine the total number of atoms in a molecule of ethene, CH,. number AtOMS 0.

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2. 0654/42 · May/June 2025 · Q6a(i)[1]

   Deduce the molecular formula of molecule X. molecular formula of X =

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3. 0654/42 · May/June 2025 · Q6a(ii)[1]

   Explain why molecule X is not a hydrocarbon.

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4. 0654/33 · October/November 2024 · Q2b(i)[1]

   State the total number of atoms in one molecule of sulfuric acid.

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5. 0654/33 · October/November 2024 · Q2b(ii)[1]

   State the total number of different elements found in one molecule of sulfuric acid.

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What examiners said

There were a wide variety of incorrect responses. Occasionally, candidates miscounted the number of hydrogen atoms.

— Examiner report, May/June 2025, 0654/42 Q6(a)(i) (Cambridge)

This question was answered well with many candidates recognising that hydrocarbons only consist of carbon atoms and hydrogen atoms.

— Examiner report, May/June 2025, 0654/42 Q6(a)(ii) (Cambridge)