Answer:
The answer to your question is a) 70 moles of COâ‚‚
                           b) 67.2 moles of CO₂
Explanation:
Data
moles of Câ‚‚Hâ‚‚ = 35
moles of Oâ‚‚ = 84
Balanced chemical equation
         2C₂H₂  +  5O₂  ⇒  4CO₂  +  2H₂O
Process
1.- Moles of COâ‚‚
        2 moles of C₂H₂ ------------------- 4 moles of CO₂
       35 moles of C₂H₂ -------------------  x
                     x = (35 x 4)/2
                    x = 70 moles of CO₂
2.- Moles of COâ‚‚
        5 moles of O₂ ----------------------- 4 moles of CO₂
        84 moles of O₂ -----------------------  x
                 x = (84 x 4) / 5
                 x = 67.2 moles of CO₂
