If 40 moles of CH₄ combine with 72 moles of O₂, how many moles of CO₂ can form? What is the limiting reagent in the reaction CH₄(g) + 2O₂(g) -> CO₂(g) + 2H₂O(g)?
a) 20 moles of CO₂; CH₄ is the limiting reagent
b) 40 moles of CO₂; CH₄ is the limiting reagent
c) 80 moles of CO₂; O₂ is the limiting reagent
d) 160 moles of CO₂; O₂ is the limiting reagent