Question

How do you calculate the percentage of calcium in calcium carbonate, `CaCO_3`?

Answer 1

40.04 %

Explanation:

You take the atomic mass of calcium over the atomic mass of `CaCO_3` and multiply it by 100 to get the percentage.

The mass of `Ca` is 40.078 g; the mass of `C` is 12.01 g, and the mass of `3O`
is 47.997 g (`"15.999 g" xx 3`).

Add all the masses together to get a total mass of 100.085 g.

So, `("40.078 g")/("100.085 g") = "0.4004 or 40.04 %"`.