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For the question "Calculate the mass(in grams)of calcium carbonate present in a 50.00mL sample of an aqueous calcium carbonate standard, assuming the standard is known to have a hardness of 75.0 ppm (hardness due to CaCO3).", the answer is 3740gCaCO3
For the question "If the 50.00mL sample from problem 2 above was titrated with a 0.00500MEDTA, what volume (in milliliters) of EDTA solution would be needed to reach the endpoint?", the answer is 7470.L of EDTA.