This practical can be adapted to determine the amount of calcium carbonate in a variety of different substances ranging from eggs shells to the shells of sea creatures, such as crabs, or in natural or artificial stone such as marble, limestone cliffs or lime mortar from old buildings. The basic reaction is simply: CaCO3(s) + 2HCl(aq) → CaCl2(aq) + CO2(g) + H2O(l)It is not practical to measure the exact amount of acid...