Question

Consider the following reaction:
CaCO3(s) --> CaO(s) + CO2(g)

A mixture of calcium oxide (CaO) and calcium carbonate (CaCO3) had a mass of 15.08 g and was heated to above 840 oC. After heating, 9.83 g of solid was left. What is the mass percentage of CaCO3(s) in the original mixture?

Answer 1

CaCO3(s) --> CaO(s) + CO2(g)
initial mass = 15.08g
final mass...= 9.83
mass CO2 lost = 15.08-9.83 = ?
Convert mass CO2 to mass CaCO3 using the coefficients in the balanced equation.
%CaCO3 = (mass CaCO3/mass sample)*100 = ?