What is the total number of moles represented by 20 grams of CACO3

A. 0.1

B. 0.2

C. 1

D. 2

B. 0.2.

Explanation:

We can use the relation:

n = mass/molar mass

mass of CaCO₃ = 20 g, molar mass of CaCO₃ = 100.0869 g/mol.

∴ n = mass/molar mass = (20 g) / (100.0869 g/mol) = 0.1998 ≅ 0.2 mol.

So, the right choice is: B. 0.2.