The equation for the complete combustion of methane is CH4(g) + 2O2(g) ® 2H2O(g) + CO2(g). If 50 L of methane at STP are burned, what volume of carbon dioxide will be produced at STP?

Answer 1

By the Ideal Gas Law, we know that 1 mol of any gas is equivalent to 22.4 L of that gas at STP. We can use this fact to determine the volume of CO₂ that is produced at STP.

50 L CH₄ x (1 mol CH₄/22.4 L CH₄) x (1 mol CO₂/1 mol CH₄) x (22.4 L CO₂/1 mol CO₂) =

50 L CO₂

Alternatively, we could take advantage of the fact that since CH₄ and CO₂ are in a 1:1 molar ratio, then they must be the same volume, as they both would correspond to an equivalent number of moles.