A. K α e-E/RT
B. K α eE/RT
C. K α T . e-E/RT
D. K α √T . e-E/RT
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 - 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 - 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 - According to Arrhenius equation of temperature dependency of rate constant for an elementary reaction _________________?
A. k ∝ √T
B. k ∝ e-E/RT
C. k ∝ T e-E/RT
D. None of these - At a given value of E/R (ratio of activation energy and gas constant), the ratio of the rate constants at 500°K and 400°K is 2, if Arrhenius law is used. What will be this ratio, if transition state theory is used with the same value of „E/R‟ ?
A. 1.6
B. 2
C. 2.24
D. 2.5 - 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 - The rate of a gas phase reaction is given by K . CA . CB. If the volume of the reaction vessel is reduced to l/4th of its initial volume, then the reaction rate compared to the original rate will be _______________ times?
A. 4
B. 16
C. 8
D. 2 - With increase in temperature, the rate constant obeying Arrhenius equation____________________?
A. Increases
B. Decreases
C. Decreases exponentially
D. Can either increase or decrease; depends on the frequency factor - For the chemical reaction P → Q, it is found that the rate of reaction doubles as the concentration of ‘P’ is doubled. If the reaction rate is proportional to Cp n, then what is the value of ‘n’ for this chemical reaction ?
A. 0
B. 1
C. 2
D. 3
