The balanced chemical equation for the reaction between CaCO3 and HCl is:

CaCO3 + 2HCl → CaCl2 + CO2 + H2O


The molar mass of CaCO3 is 100.1 g/mol, and the molar mass of HCl is 36.5 g/mol.


Since 1 litre of 1 N HCl contains 1 mole of HCl, the number of moles of HCl used in the reaction is:

1 N = 1 mole/L

Therefore, the number of moles of HCl used is 1 mole.


Using the balanced chemical equation, we can see that 1 mole of CaCO3 reacts with 2 moles of HCl. Therefore, the number of moles of CaCO3 used in the reaction is:

1 mole of CaCO3 = 2 moles of HCl

Therefore, the number of moles of CaCO3 used is 0.5 moles.


Using the balanced chemical equation, we can see that 1 mole of CaCO3 produces 1 mole of CO2. Therefore, the number of moles of CO2 produced in the reaction is:

1 mole of CaCO3 = 1 mole of CO2

Therefore, the number of moles of CO2 produced is also 0.5 moles.


The weight of CO2 obtained can be calculated using the molar mass of CO2 and the number of moles of CO2 produced:

Weight of CO2 = Number of moles of CO2 x Molar mass of CO2
Weight of CO2 = 0.5 moles x 44.0 g/mol
Weight of CO2 = 22.0 g

Therefore, the weight of CO2 obtained from the reaction of 100g CaCO3 with 1 litre 1 N HCl is 22.0 g.