A. Increases
B. Decreases
C. Decreases exponentially
D. Can either increase or decrease; depends on the frequency factor
Related Mcqs:
- The temperature dependence of reaction rate constant (K) by Arrhenius law is given by_______________?
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 - 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 - Arrhenius equation shows the variation of ___________________ with temperature?
A. Reaction rate
B. Rate constant
C. Energy of activation
D. Frequency factor - Arrhenius equation represents graphically the variation between the ______________ and temperature?
A. Rate of reaction
B. Frequency factor
C. Rate constant
D. Activation energy - The rate of a chemical reaction is almost doubled for every 10°C rise in temperature. The rate will increase ______________ times, if the temperature rises from 10 to 100°C?
A. 256
B. 512
C. 112
D. 612 - 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 - 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 - A CSTR is to be designed in which an exothermic liquid phase first order reaction of the type, A → R, is taking place. The reactor is to be provided with a jacket in which coolant is flowing. Following data is given: CA0= 5 kmole/m3; XA = 0.5; Feed temperature = reactor temperature = 40°C. Rate constant at 40°C = 1 min-1; (ΔH) = – 40kJ/mole; ρ = 1000kg/m3 CP = 4 J/gm.°C ; q = 10-3 m3/min (ρ and CP are same for the reactant and product streams). The amount of heat to be removed is_________________?
A. 2/3 kW
B. 1 kW
C. 5/3 kW
D. 4 kW - From Arrhenius law, a plot of loge K versus 1/T gives a straight line with a slope of (-E/R). The unit of E/R is___________________?
A. k cal
B. k cal/°K
C. °K
D. k cal. °K
