Select the right one. Explain short.

1. When are unsteady state reactors encountered? a. CSTR in normal operation b. Semi batch reactor c. Catalytic reactions d. Multiple reactions

2. When are unsteady state reactors encountered? a. CSTR in start up b. PFR in normal operation c. Catalytic reactions d. Multiple reactions

3. When are unsteady state reactors encountered? a. CSTR in normal operation b. PFR in normal operation c. Catalytic reactions d. Emergency situations run away reactions etc

4. When are unsteady state reactors encountered? a. CSTR in normal operation b. PFR in normal operation c. Catalytic reactions d. Adiabatic batch reactors

5. A CSTR reactor is cooled with an external heat jacket. The heat transfer fluid has a very high mass flow rate. Which of the following equations is the easiest way to calculate the heat transfer to the reactor? All notation is the same as the lecture notes, T is reactor temperature, Ta is heat transfer fluid temperature. a. Q=mCp(Ta-T) b. Q=mCp(Ta-T)(1-exp(UA/mCp)) c. Q=mCp(Ta1-Ta2) d. Q=mCp(Ta2-Ta1)

6. A CSTR reactor is cooled with an external heat jacket. The heat transfer fluid mass flow rate is quite low. Which equation can be used to calculate the heat transfer to the reactor? All notation is the same as the lecture notes, T is reactor temperature, Ta is heat transfer fluid temperature. a. Q=mCp(Ta-T) b. Q=mCp(Ta-T)(1-exp(UA/mCp)) c. Q=mCp(Ta1-Ta2) d. Q=mCp(Ta2-Ta1)

7. One condition for a runaway reaction is if the heat generated is greater than the maximum heat removed possible, expressed mathematically if [(Hrxn)(V)(-ra)]>[UA(T-Ta)]. Considering this, how could a failure in mixing of the reaction fluid lead to a safety concern? a. The heat transfer fluid flowrate would stop b. Hot spots could develop leading to rapid temperature generation c. The Ws term in the energy equation would change d. The conversion would drop

8. One condition for a runaway reaction is if the heat generated is greater than the maximum heat removed possible, expressed mathematically if [(Hrxn)(V)(-ra)]>[UA(T-Ta)]. Considering this, how could a failure in mixing of the reaction fluid lead to a safety concern? a. The heat transfer fluid flowrate would stop b. The U value will decrease c. The Ws term in the energy equation would change d. The reactant would drop

9. One condition for a runaway reaction is if the heat generated is greater than the maximum heat removed possible, expressed mathematically as [(Hrxn)(V)(-ra)]>[UA(T-Ta)]. Considering this, how could filling a vessel to a larger volume than the reaction normally proceeds at lead to a safety concern? a. The heat transfer fluid flowrate would stop b. Hot spots could develop leading to rapid temperature generation c. The heat generated would increase d. The U value will decrease, reducing heat transfer

10.How could conditions that promote an unwanted side reaction lead to a safety concern? a. The concentration of reactants would decrease b. Hot spots could develop leading to rapid temperature generation c. The heat of reaction may be higher d. The reaction kinetics will be affected