A. Decreases
B. Increases
C. Is at the highest allowable temperature throughout
D. First increases and then decreases
Related Mcqs:
- A second order liquid phase reaction, A → B, is carried out in a mixed flow reactor operated in semi batch mode (no exit stream). The reactant A at concentration CAF is fed to the reactor at a volumetric flow rate of F. The volume of the reacting mixture is V and the density of the liquid mixture is constant. The mass balance for A is_______________________?
A. d(VCA)/dt = -F (CAF – CA) – kCA2V
B. d(VCA)/dt = F (CAF – CA) – kCA2V
C. d(VCA)/dt = -FCA – kCA2V
D. d(VCA)/dt = FCAF – kCA2V - An endothermic aqueous phase first order irreversible reaction is carried out in an adiabatic plug flow reactor. The rate of reaction ?
A. Is maximum at the inlet of the reactor
B. Goes through a maximum along the length of the reactor
C. Goes through a minimum along the length of the reactor
D. Is maximum at the exit of the reactor - The following gas phase reaction is taking place in a plug flow reactor. A stoichiometric mixture of A and B at 300 K is fed to the reactor. At 1 m along the length of the reactor, the temperature is 360 K. The pressure drop is negligible and an ideal gas behaviour can be assumed. Identify the correct expression relating the concentration of A at the inlet (CA0), concentration of A at 1m (CA) and the corresponding conversion of A (X) ?
A. CA = 1.2 CA0 (1 – X)/(1 – 0.33X)
B. CA = 1.2 CA0 (1 – X)/(1 – 0.5X)
C. CA = 0.83 CA0 (1 – X)/(1 – 0.33X)
D. CA = 0.83 CA0 (1 – X)/(1 – 0.5X) - The gas phase reaction 2A ⇌ B is carried out in an isothermal plug flow reactor. The feed consists of 80 mole % A and 20 mole % inerts. If the conversion of A at the reactor exit is 50%, then CA/CA0 at the outlet of the reactor is _______________________?
A. 2/3
B. 5/8
C. 1/3
D. 3/8 - With increase in the order of reaction (for all positive reaction orders), the ratio of the volume of mixed reactor to the volume of plug flow reactor (for identical feed composition, flow rate and conversion)?
A. Increases
B. Decreases
C. Remain same
D. Increases linearly - A liquid phase reaction is to be carried out under isothermal conditions. The reaction rate as a function of conversion has been determined experimentally and is shown in the figure given below. What choice of reactor or combination of reactors will require the minimum overall reactor volume, if a conversion of 0.9 is desired ?
A. CSTR followed by a PFR
B. PFR followed by a CSTR
C. CSTR followed by a PFR followed by a CSTR
D. PFR followed by a CSTR followed by a PFR - An irreversible aqueous phase reaction, A + B → P, is carried out in an adiabatic mixed flow reactor. A feed containing 4kmole/m3 of each A and B enters the reactor at 8m3 /hr. If the temperature of the exit stream is never to exceed 390 K, what is the maximum inlet feed temperature allowed? Data: Heat of reaction = – 50 kJ/mole Density of the reacting mixture = 1000kg/m3 Specific heat of reacting mixture = 2kJ/kg.K The above data can be assumed to be independent of temperature and composition?
A. 190
B. 290
C. 390
D. 490 - The reaction A → B is conducted in an adiabatic plug flow reactor (PFR). Pure A at a concentration of 2 kmol/m3is fed to the reactor at the rate of 0.01 m3 /s and at a temperature of 500 K. If the exit conversion is 20%, then the exit temperature (in k) is (Data: Heat of reaction at 298 K = – 50000 kJ/ kmole of A reacted Heat capacities CPA = CPB = 100kJ/kmole. K (may be assumed to be independent of temperature)) ?
A. 400
B. 500
C. 600
D. 1000 - An isothermal aqueous phase reversible reaction, P ⇌ R, is to be carried out in a mixed flow reactor. The reaction rate in k.mole/m3 .h is given by, r = 0.5CP – 0.125CR. A stream containing only P enters the reactor. The residence time required (in hours) for 40% conversion of P is_________________?
A. 0.80
B. 1.33
C. 1.60
D. 2.67 - ‘N’ plug flow reactors in series with a total volume ‘V’ gives the same conversion as a single plug flow reactor of volume ‘V’ for _______________ order reactions?
A. First
B. Second
C. Third
D. Any
