%mFe(trong FeO)=56/56+16.100%=77.78%
%mO(trong FeO)=16/56+16.100%=22.22%
%mc(trongCO2)=12/12+16.2.100%=27.27%
%mO(trong CO2)=16.2/16.2.12.100%=72.72%
%mCa(trong CaCO3)=40/40+12+16.3.100%=40%
%mC(trongCaCO3)=12/12+16.3+40.100%=12%
%mO(trong CaCO3)=100%-12%-40%=48%