A. keff = k + kg
B. keff = (k+ kg)/2
C. keff = (kkg)1/2
D. 1/keff = 1/k + 1/kg
Related Mcqs:
- Rate constant for a first order reaction does not depend upon reaction time, extent of reaction and the initial concentration of reactants; but it is a function of reaction temperature. In a chemical reaction, the time required to reduce the concentration of reactant from 100 gm moles/litre to 50 gm moles/litre is same as that required to reduce it from 2 gm moles/litre to 1 gm mole/litre in the same volume. Then the order of this reaction is ?
A. 0
B. 1
C. 2
D. 3 - Following isothermal kinetic data are obtained in a basket type of mixed flow reactor for a porous catalyst. Determine the role of pore diffusion and external mass transfer processes ?
A. Strong pore diffusion control and mass transfer not controlling
B. Both pore diffusion and mass transfer not controlling
C. Both pore diffusion and mass transfer controlling
D. Mass transfer controlling - The rate expression for a heterogeneous catalytic reaction is given by, – rA = K.KA PA(1 + KA.PA + KR.PR), where K is surface reaction rate constant and KA and KR are absorption equilibrium constants of A and R respectively. If KR PR >> (1 + KA PA), the apparent activation energy EA is equal to (given E is the activation energy for the reaction and ΔHR and ΔHA are the activation energies of adsorption of R and A) ?
A. E
B. E + ΔHA
C. E + ΔHA – ΔHR)
D. ΔHA + ΔHR - 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 - 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 - A reaction which is catalysed by a base is catalysed by all substances which have a tendency to_______________________?
A. Lose a proton
B. Gain a proton
C. Gain an electron
D. None of these - A reaction which is catalysed by an acid is also catalysed by any substance, which has a tendency to _________________?
A. Lose a proton
B. Gain a proton
C. Lose an electron
D. None of these - Rate of a gaseous phase reaction is given by the reaction shown in the bellow figure. The unit of rate constant is__________________?
A. (atm)-1
B. (hr)-1
C. (atm)-1.(hr)-1
D. atm.(hr)-1 - For a gaseous phase reaction, rate of reaction is equal to K. CA . CB. If the volume of the reactor is suddenly reduced to 1/4th of its initial volume, then the rate of reaction compared to the original rate will be ______________ times?
A. 8
B. 16
C. 1/8
D. 1/16 - For a solid catalysed chemical reaction, the effectiveness of solid catalyst depends upon the ______________ adsorption?
A. Physical
B. Chemical
C. Both A. and B.
D. Neither A. nor B.
