Home / Chemical Engineering / Chemical Reaction Engineering :: Section-11

Chemical Engineering :: Chemical Reaction Engineering

  1. The response curve for a step input signal from a reactor is called C-curve. The variance of C-curve in a 'tanks in series model' comprising of 'm' tanks is equal to

  2. A.

     m

    B.

     1/m

    C.

     √m

    D.

     m²


  3. Reactions with high activation energy are

  4. A.

     Very temperature sensitive

    B.

     Temperature insensitive

    C.

     Always irreversible

    D.

     Always reversible


  5. The minimum energy required to allow a chemical reaction to proceed is termed as the 'threshold energy '. Chemical reaction with low activation energy are

  6. A.

     Always irreversible

    B.

     Insensitive to temperature changes

    C.

     Mostly irreversible

    D.

     Highly temperature sensitive


  7. In a semi-batch reactor,

  8. A.

     Mixing takes place in axial direction only

    B.

     Velocity of reaction can be controlled

    C.

     Condition similar to plug flow reactor exists

    D.

     Residence time is constant


  9. Catalytic action in a catalytic chemical reaction follows from the ability of catalyst to change the

  10. A.

     Activation energy

    B.

     Equilibrium constant

    C.

     Heat of reaction

    D.

     None of these


  11. If the catalyst pore size is small in comparison with the mean free path, collisions with the pore wall controls the process'. The diffusivity under this condition is called 'Knudsen diffusivity', which is affected by the

  12. A.

     Pressure

    B.

     Temperature

    C.

     Both A & B

    D.

     Neither A nor B


  13. The energy of activation of a chemical reaction

  14. A.

     Is same as heat of reaction at constant pressure

    B.

     Is the minimum energy which the molecules must have before the reaction can take place

    C.

     Varies as fifth power of the temperature

    D.

     Both B and C


  15. Backmixing is most predominant in

  16. A.

     A well stirred batch reactor

    B.

     A plug-flow reactor

    C.

     A single CSTR

    D.

     CSTR's connected in series


  17. Pick out the wrong statement.

  18. A.

     In a batch reactor, which is exclusively used for liquid phase reactions; temperature pressure and composition may vary with time

    B.

     In a semi-batch reactor, one reactant is charged batchwise, while the other reactant is fed continuously

    C.

     In a continuous flow reactor, uniform concentration can not be maintained throughout the vessel even in a well agitated system

    D.

     N a continuous flow reactor, both the reactants and the products flow out continuously


  19. Time required for 50% decomposition of a liquid in an isothermal batch reactor following first order kinetics is 2 minutes. The time required for 75% decomposition will be about __________ minutes.

  20. A.

     3

    B.

     4

    C.

     6

    D.

     8