Write the balanced chemical equation for the combustion of octane and calculate the mass needed to release 5 mol of CO2

Answer 1

Octane = C₈H₁₈

molar mass C₈H₁₈ = 114 g/mol

Reaction:

2C₈H₁₈ + 25 O₂ ==> 16CO₂ + 18H₂O ... balanced equation

5 mol CO₂ x 2 mol C₈H₁₈ / 16 mol CO₂ x 114 g/mol C₈H₁₈ = 71.3 g C₈H₁₈ = 70 g C₈H₁₈ (1 sig. fig.)