The volume of carbon monoxide (IV), which must be passed through a solution of calcium hydroxide to obtain 8.1 g of calcium bicarbonate, is

Reaction equation:
2CO2 + Ca (OH) 2 = Ca (HCO3) 2
From the condition m (Ca (HCO3) 2) = 8.1 g. We find the amount of calcium bicarbonate substance:
n (Ca (HCO3) 2) = m (Ca (HCO3) 2) / M (Ca (HCO3) 2) = 8.1 / 162 = 0.05 mol.
In the reaction equation, CO2 has a coefficient of 2, and Ca (HCO3) 2 is a factor of 1. Therefore, the amount of CO2 in terms of the amount of Ca (HCO3) 2 can be expressed as follows:
n (CO2) = n (Ca (HCO3) 2) ⋅ 2/1 = 0.05 ⋅ 2 = 0.1 mol,
Hence:
B (CO2) = n (CO2) ⋅ Vm = 0.1 ⋅ 22.4 = 2.24 L