A student investigated the thermal decomposition of calcium carbonate: CaCO₃ → CaO + CO₂. The student heated 10.0 g of calcium carbonate until no further reaction occurred. What volume of carbon dioxide, in dm³, was produced at r.t.p.? [Relative atomic masses: C = 12, O = 16, Ca = 40]

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Question

A student investigated the thermal decomposition of calcium carbonate: CaCO₃ → CaO + CO₂. The student heated 10.0 g of calcium carbonate until no further reaction occurred. What volume of carbon dioxide, in dm³, was produced at r.t.p.? [Relative atomic masses: C = 12, O = 16, Ca = 40]

Accepted Answer

2.4 — 4 dm³). Award 1 mark for correct answer. Mr of CaCO₃ = 40 + 12 + (16 × 3) = 100. Moles of CaCO₃ = 10.0 ÷ 100 = 0.1 mol. From the equation, 1 mol CaCO₃ produces 1 mol CO₂, so 0.1 mol CO₂ is produced. Volume = 0.1 × 24 = 2.4 dm³. A is incorrect because this uses molar volume of 12 dm³. C is incorrect because this assumes 0.2 mol CO₂. D is incorrect because this assumes 1 mol CO₂.

Answer

2.4

Answer

24.0

Answer

4.8

Answer

1.2

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