Question

the density of the sample is 0.9977 g/mL and the molar mass of calcium carbonate is 100.0 g/mol.
2. Calculate the number of moles of calcium ions present in a 50.00 mL water
sample that has a hardness of 75.0 ppm (hardness due to CaCO3).
3. If the 50.00 mL sample from problem 2 above was titrated with a 0.00500 M
EDTA, what volume (in milliliters) of EDTA solution would be needed to reach
the endpoint?

If someone could show their work and help me out that would be great. I always seem to get hung up on setting the problem up.

Thank you.