A gas mixture with 20% O2 with pressure 100 Pa at 27oC at the rate 50 liter/s is passed through a reactor and products a gas mixture with 40% O2 with pressure 25 Pa at 27oC, what is the rate of product?

Correct Answer: 100 liter/s
O2 balance: 0.2*100*50 = 0.4*25*P, => P = 100 liter/s.