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A-LevelChemistryChemical energetics9701/12 · Feb/Mar 2018 · Q81 Mark

Which equation represents the standard enthalpy change of formation of water?

AH₂(g) + ½ O₂(g) → H₂O(g)
BH₂(g) + ½ O₂(g) → H₂O(l)
C2H₂(g) + O₂(g) → 2H₂O(g)
D2H₂(g) + O₂(g) → 2H₂O(l)

✓ Correct answer

B: H₂(g) + ½ O₂(g) → H₂O(l)

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About this question

Topic
Chemical energetics, A-Level Chemistry (syllabus 9701). Multiple choice, 1 mark.
Source
A-Level Chemistry, Feb/Mar 2018 Paper 1 Variant 2, question 8.

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