Question

Calculate the mass of CO2 that would be obtained by completely
dissolving 10kg of pure CaCO3 in HCl.

Answer 1

let W Kg. obtained CO2
CaCO3  +  2HCl   -----------------------> CaCl2 + CO2 + H2O
number of mole CaCO3 = number of mole of CO2
number of mole = weight / molecular weight 
10*1000/100 = W/44         (molecular weight of CaCO3 = 100 & CO2 = 44)
W = 4000 gm.
W = 4.4 Kg.