Calculate the weight of lime(CaO) obtained by heating 200kg of 95% pure limestone(CaCO3)

95% of 200 kg = 190 kg.
The molar mass of CaCO₃ is 100 g/mol, so 190 kg = (190,000 g)/(100 g/mol)
= 1900 mol.
CaCO₃ → CaO + CO₂, so 1900 mol of CO₂ are removed by heating. The molar mass of CO₂ is 44 g/mol, so 1900 mol = (1900 mol)(44 g/mol) = 83 600 g = 83.6 kg.
190 kg - 83.6 kg = 106.4 kg CaO.

95% pure means you have 95/100*200 = 190kg pure CaCO3

Molar mass CaO = 56g/mol
molar mass CacO3 = 100g/mol

Mass CaO produced from 190kg CaCO3 = 56/100*190 = 106.4kg CaO produced.

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