For problems 2 & 3, the density of the sample is 0.9977 g/ml and the molar mass of calcium carbonate is 100.0 g/mol.
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).
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?

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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.