Helium-mercury method is used for the measurement of the ________________ of the catalyst?

Related Mcqs:

1. Helium-mercury method can be used to determine the _____________ of the catalyst particle?

   A. Pore volume
   B. Solid density
   C. Porosity
   D. All A., B., & C.

2. 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

3. 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.

4. 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

5. If helium is introduced in a reactor containing O2, SO2 and SO3 at equilibrium, so that total pressure increases while volume and temperature remains constant. In this case the dissociation of SO3 (as per Le Chatelier’s principle)?

   A. Decreases
   B. Increases
   C. Remains unaltered
   D. Changes unpredictably

6. B.E.T. method can be used to determine the ___________________ of a porous catalyst?

   A. Solid density
   B. Pore volume
   C. Surface area
   D. All A., B. and C.

7. _____________ gas is normally employed in B.E.T. method of finding out the surface area of catalyst?

   A. N2
   B. H2
   C. CO2
   D. He

8. B.E.T. method of finding out surface area of a catalyst, uses the extension of _________________ isotherm?

   A. Langmuir
   B. Freundlich
   C. Tempkin
   D. None of these

9. Overall rate of reaction in a heterogeneous catalytic reaction depends upon the mass and energy transfer from the fluid to solid surface and its rate of reaction is usually ________________ the concentration of catalyst, if it does not entail a chain mechanism?

   A. Proportional to
   B. Independent of
   C. Inversely proportional to
   D. Proportional to the square of

10. If Thiele modulus is ________________, then the pore diffusion resistance in a catalyst may be considered as negligible?

    A. 0
    B. ∞
    C. < 0.5
    D. > 0.5