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A-LevelChemistryChemical energetics9701/12 · Oct/Nov 2019 · Q61 Mark

Which reaction is endothermic?

ACa(OH)₂(aq) + 2HCl(aq) → CaCl₂(aq) + 2H₂O(l)
B2Cl(g) → Cl₂(g)
C2Ca(s) + O₂(g) → 2CaO(s)
DCaCO₃(s) → CaO(s) + CO₂(g)

✓ Correct answer

D: CaCO₃(s) → CaO(s) + CO₂(g)

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About this question

Topic
Chemical energetics, A-Level Chemistry (syllabus 9701). Multiple choice, 1 mark.
Source
A-Level Chemistry, Oct/Nov 2019 Paper 1 Variant 2, question 6.

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