When limestone (solid CaCO3) is heated, it decomposes into

Last updated: 7/25/2022

When limestone (solid CaCO3) is heated, it decomposes into lime (solid CaO) and carbon dioxide gas. This is an extremely useful industrial process of great antiquity, because powdered lime mixed with water is the basis for mortar and concrete - the lime absorbs CO₂ from the air and turns back into hard, durable limestone. Suppose some calcium carbonate is sealed into a limekiln of volume 500. L and heated to 520.0 °C. When the amount of CaCO3 has stopped changing, it is found that 3.84 kg have disappeared. Calculate the pressure equilibrium constant Kp, this experiment suggests for the equilibrium between CaCO3 and CaO at 520.0 °C. Round your answer to 2 significant digits. Note for advanced students: it's possible there was some error in this experiment, and the value it suggests for Kp, does not match the accepted value. Kp =