Dissolving 3.00 g of an impure sample of calcium carbonate in excess hydrochloric acid produced 0.656 L of carbon dioxide (measured at 20.0oC and 792 mmHg). The equation for the reaction is: CaCO3 (s) + 2HCl → CaCl2 (aq) + 2H2O (l) + CO2 (g) Calculate the percent by mass of calcium carbonate in the sample, assuming 100% efficiency.