A. Increases the equilibrium concentration of the product
B. Changes the equilibrium constant of the reaction
C. Shortens the time to reach the equilibrium
D. None of these
Related Mcqs:
- 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 - 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. - 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 - 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 - The importance of diffusion in a catalyst are increased by ____________________?
A. Large catalyst particle size
B. An active surface of the catalyst
C. Small pore diameter
D. All A., B. and C. - _____________ 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 - 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 - Effectiveness factor of a catalyst pellet is a measure of the _________________ resistance?
A. Pore diffusion
B. Gas film
C. Chemical reaction
D. None of these - The reaction in which one of the products of reaction acts as a catalyst is called a/an ______________ reaction?
A. Biochemical
B. Photochemical
C. Catalytic
D. Autocatalytic - When a catalyst increases the rate of forward reaction, the value of rate constant__________________?
A. Increases
B. Decreases
C. Remain same
D. Becomes infinite
