Organic catalysts differ from the inorganic catalyst in the sense that the former is________________?

Related Mcqs:

1. Effectiveness factor E. of a catalyst pellet is defined as, E = (actual rate within pore of the catalyst)/(rate if not snowed by pore diffusion), Effectiveness factor for a first order reaction is given by (where, T = Thiele modulus) ___________________?

   A. tan hT/T
   B. tan T/T
   C. tan hT/tan T
   D. None of these

2. A catalyst is said to be a negative catalyst, if it ___________________?

   A. Retards the rate of reaction
   B. Reduces the value of equilibrium constant
   C. Does not initiate the reaction
   D. All A., B. and C.

3. A spherical porous catalyst particle of radius R is subjected to reactant A which reacts to form B by a zero order surface reaction A → B. Film mass transfer resistance is negligible and pore diffusion of A is rate controlling. The effectiveness factor of the catalyst is reported as 7/8. Which of the following statement is true?

   A. Inner catalyst core of radius R/8 does not participate in reaction
   B. Inner catalyst core of radius R/2 does not participate in reaction
   C. Inner catalyst core of radius 7R/8 does not participate in reaction
   D. Effectiveness factor for a zero order reaction cannot be 7/8 as it must always be 1

4. Enzymes (a protein) are catalysts found in organisms. Its efficiency of catalysing a reaction is due to its capacity to lower the activation energy of the reaction. The enzyme ptyalin used for food digestion is present in ___________________?

   A. Blood
   B. Saliva
   C. Intestine
   D. Gland

5. Pure ethanol vapor is fed to a reactor packed with alumina catalyst, at the rate of 100 kmole / hr. The reactor products comprise: ethylene: 95 kmole / hr, water vapour: 97.5 k mole / hr and diethyl ether: 2.5 kmole/hr. The reactions occuring can be represented by: C2H5OH → C2H4 + H2O 2C2H5OH → C2H5 – O – C2H5 + H2O The percent conversion of ethanol in the reactor is________________?

   A. 100
   B. 97.5
   C. 95
   D. 2.5

6. A catalyst in a chemical reaction____________________?

   A. Decreases the activation energy
   B. Alters the reaction mechanism
   C. Increases the frequency of collisions of reacting species
   D. All A., B. and C.

7. Promoter is added to the catalyst to improve its____________________?

   A. Porosity
   B. Sensitivity
   C. Surface area
   D. None of these

8. For a first order chemical reaction in a porous catalyst, the Thiele modulus is 10. The effectiveness factor is approximately equal to ____________________?

   A. 0
   B. 1
   C. 0.1
   D. 0.5

9. A catalyst in a chemical reaction _______________ free energy change in the reaction?

   A. Increases
   B. Decreases
   C. Either A. or B.; depends on the type of catalyst
   D. Neither A. nor B.

10. A reaction in which one of the products of reaction acts as a catalyst is called a/an ______________ reaction?

    A. Catalytic
    B. Autocatalytic
    C. Photochemical
    D. None of these