Question

A few Drops of HCl spilled over in the CaCO3 sample. Will the Reported percent of CaCO3 be too high, too low or unaffected?

Answer 1

Since the HCl reacts with the CaCO₃, I'd say the % would be less.

And, it would be carbonated!

Answer 2

I don't think this is a very good question, mostly because I don't think it has an answer. Yes, the HCl reacts with the CaCO3 and if you are measuring the CO2 output then the results will be too low; however, we don't know how much the water (in which the HCl was dissolved) weighs so the loss of CO2 + gain by water is the overall gain/loss. We don't know what that is because we don't know the mass of the water.