Assuming a 70.% yield in the overall reaction, discuss what mass of limestone is needed to remove all the sulfur dioxide produced by the combustion of 8.5*104kg of coal that is0.33 mass % sulfur? The Limestone (CaCO3) is used to remove the acidic pollutants from smokestack flue gases. It is heated to form lime (CaCO3), which reacts with sulfur dioxide to produce the calcium sulfite.