Calcium Carbonate has a molecular formula of CaCO3 and a molar mass of 100.0869 g/mol. The molar mass of calcium is 40.078 g/mol so the percent of calcium in calcium carbonate is 40.078/100.0869 which is 0.4004. We multiply this number by the mass given (0.4004*1.32 g) to obtain the mass of calcium present which is 0.52857 g. We then multiply this by (1000mg/1g) to get 528.57 mg.
