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Chapter 1
  1. In the formula for CSTR, if the rate of reaction is not constant and is dependent on the concentration, should we take to mean? the integral mean?

    Because the reactor is well-mixed, the concentrations, temperature, and rate of reaction are the same throughout the reactor volume, including the exit point. Consequently, the concentrations, temperature, and rate of reaction in the reactor are all evaluated at the exit conditions of the CSTR.

  2. What is the difference between packed bed and fluidized bed reactors?

    Packed bed- Catalyst particles are packed in a tube
    Fluidized bed- Analogous to a CSTR with catalyst, see Figure 10-16 (p.620).

  3. Why does a semi-batch reactor have better temperature control than a batch reactor?

    One can also control the feed rate of one of the reactants as well as control the heat exchanger.

  4. Why would you choose to have CSTRs and PFRs in series?

    It is what reactors you might have on hand that you could connect together to obtain a high conversion.

Chapter 2
  1. How would the problem involving three reactors in series in Chapter 2 change if there were sidestreams between?

    One can't use the definition of total conversion up to a point because the reactant is fed to the stream between reactors. One must work in terms of molar flow rates when writing the mole balances.

  2. Is there ever a time when a CSTR will have a lower volume than a PFR for the same conversion and flow rates?

    Yes, for some adiabatic reactions.

  3. In the 3-reactor series, (CSTR, PFR, CSTR) why wouldn't you just use the PFR to have the least volume overall to achieve the best conversion?

    You would if you had a PFR large enough. We are assuming that you have these reactors available for your use. See ICM-Staging.

  4. For the three reactors in series example, can a PFR use liquid like the 2 CSTRs?

    Yes.

  5. If you had three reactors and two were CSTR's and the other was a PFR, would the PFR be placed at the end to minimize volume?

    Yes, in most instances when the reaction is isothermal and the curve of (1/-rA) increases monotonically (i.e. no valleys or mountains) with X.

  6. Does (for aA + bB cC + dD) only hold for first order reactions?

    No! This relationship has only to do with stoichiometry and nothing to do with rate laws. It holds for reactions of ANY order.

  7. How do you use the equation to model reactors in parallel?

    See Example 4-2 (p.142).

Chapter 3
  1. What is the frequency factor and where can we get values for it? What is it dependent on?

    Generally the frequency factor is independent of temperatures, however on occasion it can be a weak function of temperature. See p.944

  2. Why is the limiting reactant our basis of calculation?

    One could calculate a NEGATIVE concentration otherwise. See Example 3-5 (p.90).

  3. What is the relationship between the K in chemistry (A + B <--> C) and the k in the rate laws?

    KC is an equilibrium constant, and k is specific rate constant. k has units of time, K does not.

  4. How does the k (specific reaction rate) depend on pressure, or does it?

    ONLY in very very rare instances at very high pressures such as, 6000 atm, for liquid phase reactions is k a function of pressure. See p.220 and CD-ROM on critiquing what you read.

  5. What is the frequency factor, A, in the Arrhenius Equation; I want to know what it's physical meaning is and/or what it is a frequency factor.

    Arrhenius Equation is k = Ae-E/RT
    The frequency factor, A, is the coefficient of the exponential term. It has the same units as k. It is related to the number of collisions between molecules. See p.942 and 943.

  6. What does the overall order of the power law model indicate?

    One can classify reactions by their overall order of reaction.

  7. Who determines all the rate laws?

    These can be found in the literature, journals, books, tables, etc., see the footnote on p.75. They can also be determined in the laboratory. See Ch.5