Question

how much of quicklime can be obtained by burning 400 gram of limestone

Answer 1

Pure limestone is calcium carbonate, i.e., CaCO3. Pure quicklime is calcium oxide, i.e., CaO. The atomic weights of calcium, carbon and oxygen are 40, 12 and 16 respectively. So 1 mole of limestone weighs 100 grams, 1 mole of quicklime weighs 56 grams. A “pure” conversion of 400 grams of limestone would, therefore, yield 224 grams of quicklime. But in the real world your limestone will contain impurities and your calciner or kiln will not be 100% efficient,