Răspuns:
MCaCO3 =40+12+3×16=100g/mol
MCaO =40++6=56g/mol
MCO2 =12+2×16=44g/mol
100gCaCO3........20g pur
400gCaCO3..........xg
x=20×400/100=80gpur
100g............56g.......44g
CaCO3 => CaO + CO2
80g.............yg.........zg
y=80×56/100= calculează
z=80×44/100= calculează