What volume of carbon dioxide gas is produced from this amount of calcium carbonate,
at STP?
Answers
Write the balanced chemical equation between CaCO3 and CO2:
CaCO3 + 2HCl → CaCl2 + CO2 + H2O
Its well-established that there is a 1:1 relationship between CaCO3 and CO2.
Determine the amount of CaCO3 in moles, Excess of HCl is not a big concern.
Use the molar mass of CaCO3, which is 100 g/mol:
mol CaCO3 = 50 g CaCO3 x 1 mol CaCO3/100 g CaCO3 = 0.5 mol CaCO3
Now, calculate the amount in moles of the produced CO2:
0.5 mol CaCO3 x 1 mol CO2/1 mol CaCO3 = 0.5 mol CO2.
Since CO2 is a gas, we can use the ideal gas equation (PV=nRT) to interconvert between pressure (P), volume (V), mol (n) and temperature (T).
P x V = n x R x T
or, 1 atm x V = 0.5 mol x 0.08206 (L.atm/mol.K) x 273.15
or, V = 11.2 L
else, the problem can be directly solved by the number of moles of CO2 you produced, as under STP conditions, 1 mol of an ideal gas occupies 22.4 L:
0.5 mol * 22.4 L/mol = 11.2 L.