using avogadros law

Question

Methane gas and oxygen gas react to form water vapor and carbon dioxide gas. What volume of carbon dioxide would be produced by this reaction if 2.3 m3 of oxygen were consumed? 

Answer 1

the balanced equation here is

CH4​(g) + 2O2​(g) → CO2​(g) + 2H2​O(g), meaning that for every 2 molecules of oxygen consumed, 1 molecule of carbon dioxide is produced

so in the context of this question you want to take

2.3 m^3 O2 x 1 CO2 / 2O2 = 1.15 m^3

meaning that 1.15 m^3 of carbon dioxide would be produced

Answer 2

methane = CH₄

Oxygen = O₂

CH₄ + 2O₂ ==> CO₂ + 2H₂O ... balanced equation

2.3m³ O₂ x 1 m³ CO₂ / 2 m³ O₂ = 1.15 m³CO₂ = 1.2 m³ CO₂ (2 sig. figs.)

If you want the volume in liters...

1.15 m3 CO₂ x 1000 L / 1 m³ = 1150 L CO₂ = 1200 L CO₂ (2 sig. figs.)