Calcium carbonate is a white mineral. A chemist burns calcium carbonate, CaCO3, to produce carbon dioxide, CO2, and a white powder, CaO. The chemical equation for this reaction is CaCO3 → CO2 + CaO. Compare the properties of the products and reactants in this reaction. Use numbers of atoms to describe the amounts of calcium, carbon, and oxygen before and after the reaction. Explain where the equation shows the conservation of matter.