The mass of Calcium carbonate needed : 246 g
Further explanation
Reaction
CaCO₃(s)→CaO(s)+CO₂(g)
Conditions at T 0 ° C and P 1 atm are stated by STP (Standard Temperature and Pressure). At STP, Vm is 22.4 liters / mol.
Then for 55 L of CO₂, mol :
[tex]\tt \dfrac{55}{22.4}=2.46[/tex]
From the equation, mol ratio for mol CaCO₃ : mol CO₂ = 1 : 1, so :
mol CaCO₃ = mol CO₂ = 2.46
mass CaCO₃(MW=100g/mol) :
[tex]\tt mass=mol\times MW\\\\mass=2.46\times 100\\\\mass=246~g[/tex]
