A tablet containing calcium carbonate and fillers with a mass of 1.631 g was dissolved in HCl. After the fillers were filtered out, the HCl was neutralized by adding sodium carbonate. The resulting precipitate was pure calcium carbonate (with the fillers removed). The solid calcium carbonate was collected on a watch glass that had a mass of 46.719 g when empty. After the calcium carbonate had been allowed to dry, the mass of the watch glass plus product was found to be 47.623

1. Calculate the mass percent of calcium in calcium carbonate. Report your answer to at least 3 significant figures.

Calculate dry wt of Calcium Carbonate without watch glass... Then, ratio [CaCO3(s) / tablet mass] x 100% => Wt% CaCO3

I get 55.4% w/w.

To calculate the mass percent of calcium in calcium carbonate, we need to determine the mass of calcium in the compound and divide it by the total mass of calcium carbonate.

First, let's find the mass of calcium in the calcium carbonate tablet. We know that the mass of the tablet was 1.631 g and that the resulting precipitate of calcium carbonate collected on the watch glass had a mass of 47.623 g (including the watch glass).

To find the mass of calcium, we need to subtract the mass of the watch glass from the total mass of the watch glass plus product. Therefore, the mass of calcium carbonate is:

Mass of calcium carbonate = Mass of watch glass + product - Mass of watch glass
Mass of calcium carbonate = 47.623 g - 46.719 g
Mass of calcium carbonate = 0.904 g

Now, we need to calculate the mass percent of calcium in calcium carbonate. We can express this as:

Mass percent = (mass of calcium / mass of calcium carbonate) x 100

Mass percent = (mass of calcium / 0.904 g) x 100

To proceed further, we need to know the molar mass of calcium carbonate. The molar mass of calcium carbonate is:
- Calcium (Ca) atomic mass = 40.08 g/mol
- Carbon (C) atomic mass = 12.01 g/mol
- Oxygen (O) atomic mass = 16.00 g/mol

Since there is one calcium atom, one carbon atom, and three oxygen atoms in calcium carbonate, the molar mass of calcium carbonate is:

Molar mass of calcium carbonate = (1 x 40.08 g/mol) + (1 x 12.01 g/mol) + (3 x 16.00 g/mol)
Molar mass of calcium carbonate = 100.09 g/mol

Now, we can calculate the mass percent of calcium in calcium carbonate:

Mass percent = (mass of calcium / 0.904 g) x 100
Mass percent = (40.08 g/mol / 100.09 g/mol) x 0.904 g x 100
Mass percent = 35.96 %

Therefore, the mass percent of calcium in calcium carbonate is 35.96%.