A. Fast reactions in catalyst of small pore diameter
B. Fast reaction in catalyst of large pore diameter
C. Slow reactions in catalyst of small pore diameter
D. Slow reactions in catalyst of large pore diameter
Related Mcqs:
- 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 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 - 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. - A first order gaseous phase reaction is catalysed by a non-porous solid. The kinetic rate constant and the external mass transfer co-efficients are k and kg respectively. The effective rate constant (keff) is given by________________?
A. keff = k + kg
B. keff = (k+ kg)/2
C. keff = (kkg)1/2
D. 1/keff = 1/k + 1/kg - 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 - In a chemical reaction, represented by as shown in the bellow figure, it is observed that the (i) Rate of reaction increases by a factor of 4 on doubling the concentration of the reactant. (ii) Rate of reaction increases by a factor of 9 on trebling the concentration of the reactant. Then the rate of the reaction is proportional to(where, CA = concentration of the reactant)_____________________?
A. CA
B. CA2
C. CA3
D. CA4 - For a vapour phase catalytic reaction (A + B → P) which follows the Ridel mechanism and the reaction step is rate controlling, the rate of reaction is given by (reaction rate is irreversible, product also absorbs) ?
A. -rA = (k . PA . PB)/(1 + KAPA + KPPP)
B. -rA = (k . PA
2 – k1PP)/(1 + KAPA + KPPP)
C. -rA = (k . PA . PB)/(1 + KAPB + KBPB . KPPP)
D. -rA = (k . PA . PB)/(1 + KAPA) - The rate controlling step for the heterogeneous irreversible catalytic reaction A(g) + B(g) → C(g) is the surface reaction of absorbed A with absorbed B to give adsorbed C. The rate expression for this reaction can then be written as (where, KA, KB and KC are the equilibrium constants and is the rate constant of the rate controlling step) ?
A. k KA pApB / (1 + KApA + KBpB)
B. k KAKB pApB / (1 + KApA + KBpB)
C. k KAKB pApB / (1 + KApA + KBpB + KCpC)
D. k KAKB pApB / (1 + KApA + KBpB + KCpC)2 - In a chemical reaction as shown in the bellow figure, it is observed that the (i) Rate of formation of ‘P’ is doubled on doubling the concentration of ‘X’ (ii) Rate of formation of ‘P’ is quadrupled on doubling the concentration of ‘Y’ (iii) Doubling the concentration of ‘Z’ does not affect the rate of formation of ‘P’ What is the order of the above chemical reaction ?
A. Zeroth order
B. First order
C. Second order
D. Third order