The answer key was just passed out. I don't know how these answers were received. We are using Elements of Chemical Reaction Engineering Fifth edition by Fogler. Can you explain how these answers were produced? And explain it like I'm an dingdong. Label your equations with things like "This is the design equation" "I built this equation by combining this and that equation" etc. I received a 17% on the test and I'm trying to learn but the book is difficult.

Q # 4. The gas-phase reaction (2 A + B) has been studied in an isothermal, constant pressure batch reactor. The reaction is 1st order in A. When the reactor is charged with pure A at 200 C, it takes 30 min to react half the amount of A. (a) Find the time to obtain 50% conversion in a constant volume batch reactor. (30 min) (b) Calculate the space time needed for 90% conversion in a PFR with Pure A feed. What is the mean residence time? (69.3 min, 99.7 min) Repeat part (b) for a CSTR under similar conditions. (214 min, 389 min) (c) a