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Question

From 100g of limestone, 40 g of carbon dioxide were obtained. What is the estimated calcium carbonate in limestone?

Answer 1

CaCO₃ ==> CO₂ + CaO ... balanced equation

40 g CO₂ x 1 mol CO₂ / 44 g = 0.909 moles CO₂ formed

moles CaCO₃ present = 0.909 mols CO₂ x 1 mol CaCO₃ / mol CO₂ = 0.909 mols CaCO₃

Estimated mass of CaCO₃ present = 0.909 mols CaCO₃ x 100 g / mol = 90.9 g CaCO₃ (~91%)