a, nCO2= 3,36/22,4= 0,15 mol
CaCO3+ 2HCl -> CaCl2+ CO2+ H2O
CaO+ 2HCl -> CaCl2+ H2O
=> nCaCO3= nCO2= 0,15 mol
=> mCaCO3= 0,15.100= 15g
=> mCaO= 20,6-15= 5,6g
%CaCO3= 15.100:20,6= 72,8%
%CaO= 27,2%
b, nCaO= 5,6/56= 0,1 mol
nHCl= 0,15.2+ 0,1.2= 0,5 mol
=> mdd HCl= 0,5.36,5.100:7,3= 250g
Mặt khác, nCaCl2= 0,15+ 0,1= 0,25 mol
m dd spu= 20,6+250- 0,15.44= 264g
=> C% CaCl2= 0,25.111.100:264= 10,5%