Answer: Hydrogen molecules will have greatest average speed.
Explanation:
The formula for average speed is :

R = gas constant
T = temperature
M = Molecular Mass
Now putting all the values:



Thus average speed of hydrogen is 8 times the average speed of oxygen. Thus hydrogen molecules will have greatest average speed
Answer:
15.4 mol CO₂
Explanation:
5.12 mol C₃H₈ × (3 mol CO₂ / mol C₃H₈) ≈ 15.4 mol CO₂