Question

When calcium carbonate is heated, it breaks down into calcium oxide and carbon dioxide.

CaCO3(s) →CaO(s) + CO2(g)

You heat 25 g CaCO3.

Approximately what volume of carbon dioxide will you make?

Assume the conditions of temperature and pressure are such that 1 mole of any gas will occupy 22.4 L.

Responses

1.0 L

1.0 L

5.6 L

5.6 L

11.2 L

11.2 L

22.4 L

22.4 L

Answer 1

Molar mass CaCO3 ≈ 100 g·mol−1. Moles = 25 g / 100 g·mol−1 = 0.25 mol. Reaction gives 1 mol CO2 per mol CaCO3, so CO2 = 0.25 mol. Volume = 0.25 × 22.4 L = 5.6 L.

Answer: 5.6 L.