Description : Kinetics of a catalytic reaction can be best studied on a/an __________ reactor. (A) Mixed (B) Integral (plug flow) (C) Differential (flow) (D) Either (A), (B) and (C)
Last Answer : (D) Either (A), (B) and (C)
Description : Pick out the wrong statement. (A) 'Hold back' is defined as the fraction of material that stays longer than the mean residence time (B) Study of non-ideal flow reactor is done experimentally ... final stages of reaction (D) A batch reactor cannot be used to study the kinetics of catalytic reaction
Last Answer : (D) A batch reactor cannot be used to study the kinetics of catalytic reaction
Description : Which of the following factors control the design of a fluid-solid reactor? (A) Reaction kinetics for single particle (B) Size distribution of solids being treated (C) Flow patterns of solids and fluid in the reactor (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : In a semi-batch reactor, (A) Mixing takes place in axial direction only (B) Velocity of reaction can be controlled (C) Condition similar to plug flow reactor exists (D) Residence time is constant
Last Answer : (B) Velocity of reaction can be controlled
Description : The size of plug flow reactor (PFR) for all positive reaction orders and for any given duty, is __________ that of mixed reactor. (A) Greater than (B) Equal to (C) Smaller than (D) Unpredictable from the data
Last Answer : (C) Smaller than
Description : Time required for 50% decomposition of a liquid in an isothermal batch reactor following first order kinetics is 2 minutes. The time required for 75% decomposition will be about __________ minutes. (A) 3 (B) 4 (C) 6 (D) 10
Last Answer : (B) 4
Description : For high conversion in a highly exothermic solid catalysed reaction, use a __________ bed reactor. (A) Fixed (B) Fluidised bed reactor followed by a fixed (C) Fixed bed reactor followed by a fluidised (D) Fluidised
Last Answer : (B) Fluidised bed reactor followed by a fixed
Description : 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 ... 2V (C) d(VCA )/dt = -FCA - kCA 2V (D) d(VCA )/dt = FCAF - kCA 2V
Last Answer : (D) d(VCA )/dt = FCAF - kCA 2V
Description : A pollutant P degrades according to first order kinetics. An aqueous stream containing P at 2 kmole/m3 and volumetric flow rate 1m3 /h requires a mixed flow reactor of volume V to bring down the pollutant level to 0.5 kmole/ ... reactor should be increased by a factor of: (A) 7 (B) 6 (C) 3 (D) 7/3
Last Answer : (A) 7
Description : Pick out the wrong statement. (A) The integral method of analysing kinetic data is used when the data is scattered (B) The differential method of analysing kinetic data requires more accurate ... less than one for identical feed composition, flow rate, conversion and for all positive reaction orders
Last Answer : (C) When the reaction rate is independent of temperature, the reaction is said to be of zero order
Description : 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
Last Answer : (A) Increases
Description : Pick out the wrong statement. (A) The vessel dispersion number (D/UL) for plug flow and mixed flow approaches zero and infinity respectively (B) Space time in a flow reactor is a ... ideal tubular flow reactor, mixing takes place in radial direction and there is no mixing in longitudinal direction
Last Answer : (C) Mixed reactor is always smaller than the plug flow reactor for all positive reaction orders for a particular duty
Description : Pick out the wrong statement. (A) For a first order consecutive reaction, a tubular flow reactor as compared to a stirred tank reactor provides higher overall selectivity(B) For an ideal ... D) Reaction rate does not decrease appreciably as the reaction proceeds in case of an autocatalytic reaction
Last Answer : (A) For a first order consecutive reaction, a tubular flow reactor as compared to a stirred tank reactor provides higher overall selectivity
Description : For all positive reaction orders for a particular duty, (A) Mixed reactor is always larger than the plug-flow reactor (B) Ratio of the volume of the mixed reactor to that of the plug-flow ... (C) Reactor size is independent of the type of flow (D) Density variation during reaction affects design
Last Answer : (A) Mixed reactor is always larger than the plug-flow reactor
Description : Which of the following is the most suitable for isothermal operation? (A) Batch reactor (B) Back-mix reactor (C) Plug-flow reactor (D) Fixed bed reactor
Last Answer : (B) Back-mix reactor
Description : Backmixing is most predominant in (A) A well stirred batch reactor (B) A plug-flow reactor (C) A single CSTR (D) CSTR's connected in series
Last Answer : (C) A single CSTR
Description : The effectiveness factor for large value of Thiele modulus [L√(K/D1 )] of a solid catalysed first order reaction is equal to (where, L = length of the reactor, cm, D1 = diffusion co-efficient, cm2 /second). (A) L √(K/D1 ) (B) 1/[L√(K/D1 )] (C) 1 (D) ∞
Last Answer : (B) 1/[L√(K/D1 )]
Description : For nearly isothermal operation involving large reaction time in a liquid-phase reaction, the most suitable reactor is a __________ reactor. (A) Stirred tank (B) Tubular flow (C) Batch (D) Fixed bed
Last Answer : (A) Stirred tank
Description : Which of the following is the most suitable for very high pressure gas phase reaction? (A) Batch reactor (B) Tubular flow reactor (C) Stirred tank reactor (D) Fluidised bed reactor
Last Answer : (B) Tubular flow reactor
Description : In a semi-batch reactor (A) Velocity of reaction can be controlled (B) Maximum conversion can be controlled (C) Both the reactants flow counter-currently (D) Residence time is constant
Last Answer : (A) Velocity of reaction can be controlled
Description : The conversion in a mixed reactor/accomplishing a reaction A → 3R is 50% when gaseous reactant 'A' is introduced at the rate of 1 litre/second and the leaving flow rate is 2 litres/second. The holding time for this operation is __________ second. (A) 0.5 (B) 1 (C) 2 (D) 3
Last Answer : (A) 0.5
Description : 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)
Last Answer : (B) Chemical
Description : An endothermic second order reaction is carried out in an adiabatic plug flow reactor. The rate of heat generation is: (A) Maximum at the inlet of the reactor (B) Maximum at the exit of the reactor (C) Maximum at the centre of the reactor (D) Constant throughout the reactor
Last Answer : (A) Maximum at the inlet of the reactor
Description : A backmix reactor (A) Is same as plug-flow reactor (B) Is same as ideal stirred tank reactor (C) Employs mixing in axial direction only (D) Is most suitable for gas phase reaction
Last Answer : (B) Is same as ideal stirred tank reactor
Description : A reversible liquid phase endothermic reaction is to be carried out in a plug flow reactor. For minimum reactor volume, it should be operated such that the temperature along the length (A) ... Increases (C) Is at the highest allowable temperature throughout (D) First increases and then decreases
Last Answer : (C) Is at the highest allowable temperature throughout
Description : 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 ... through a minimum along the length of the reactor (D) Is maximum at the exit of the reactor
Last Answer : (A) Is maximum at the inlet of the reactor
Description : Pick out the wrong statement: (A) Chemical reactions with high activation energy are very temperature sensitive (B) A flat velocity profile exists in a plug flow reactor (C) The residence ... D) Half life of a reaction increases with increased initial concentration for reaction orders more than one
Last Answer : (C) The residence time for all the elements of fluid in case of a P.F.R. need not be same
Description : The reaction A → B is conducted in an adiabatic plug flow reactor (PFR). Pure A at a concentration of 2 kmol/m3 is fed to the reactor at the rate of 0.01 m3 /s and at a temperature of 500 K. If the exit ... /kmole. K (may be assumed to be independent of temperature)) (A) 400 (B) 500 (C) 600 (D) 1000
Last Answer : (C) 600
Description : For series reaction, the relative yield (A) Is always greater for plug-flow reactor than for the single CSTR of the same volume (B) Statement in (A) is wrong (C) Decreases with increasing conversion (D) Both (A) and (C) hold good
Last Answer : (D) Both (A) and (C) hold good
Description : A plug-flow reactor is characterised by (A) High capacity (B) Presence of axial mixing (C) Presence of lateral mixing (D) Constant composition and temperature of reaction mixture
Last Answer : (C) Presence of lateral mixing
Description : 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
Last Answer : (B) 5/8
Description : Which of the following is the optimum operating condition for an exothermic reversible reaction taking place in a plug-flow reactor? (A) Temperature should be high in the beginning and decreased towards ... reaction (C) Very high temperature should be used throughout the reaction (D) None of these
Last Answer : (A) Temperature should be high in the beginning and decreased towards the end of the reaction
Description : For a fluidised bed reactor, the most suitable/relevant model is a __________ model. (A) Tank in series (B) Bubbling bed (C) Plug flow (D) None of these
Last Answer : (B) Bubbling bed
Description : 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
Last Answer : (D) Any
Description : Vegetable oils are hydrogenated in a __________ reactor. (A) Slurry (B) Plug flow (C) Homogeneous catalytic (D) None of these
Last Answer : (A) Slurry
Description : Hydrogenation of oil takes place in a/an __________ reactor. (A) Autothermal (B) Trickle bed (C) Plug flow (D) None of these
Last Answer : (B) Trickle bed
Description : The ratio of Murphree plate efficiency to point efficiency is always > 1 in a __________ flow model. (A) Plug (B) Perfectly mixed (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (A) Plug
Description : The ratio of Murphree plate efficiency to point efficiency is 1 in a __________ flow model. (A) Plug (B) Perfectly mixed (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (B) Perfectly mixed
Description : Fluid flow in a real packed bed can be approximated as __________ model. (A) Plug flow (B) Dispersion (C) Mixed flow (D) Tank in series
Last Answer : (B) Dispersion
Description : ........................ studied the kinetics of enzyme catalysis. a. Arrhenius b. Rutherford c. Micheal Faraday d. Michaelis & Menten
Last Answer : d. Michaelis & Menten
Description : The ratio of volume of mixed reactor to the volume of P.F.R. (for identical flow rate, feed composition and conversion) for zero order reaction is: (A) ∞ (B) 0 (C) 1 (D) > 1
Last Answer : (C) 1
Description : 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 ... (in hours) for 40% conversion of P is (A) 0.80 (B) 1.33 (C) 1.60 (D) 2.67
Last Answer : (C) 1.60
Description : . 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 ... be assumed to be independent of temperature and composition. (A) 190 (B) 290 (C) 390 (D) 490
Last Answer : (B) 290
Description : Pick out the wrong statement. (A) In a batch reactor, which is exclusively used for liquid phase reactions; temperature pressure and composition may vary with time (B) In a semi-batch reactor, ... system (D) In a continuous flow reactor, both the reactants and the products flow out continuously
Last Answer : (C) In a continuous flow reactor, uniform concentration cannot be maintained throughout the vessel even in a well agitated system
Description : The use of space time is preferred over the mean residence time in the design of a/an (A) Batch reactor (B) Ideal tubular-flow reactor (C) Slurry reactor (D) CSTR
Last Answer : (B) Ideal tubular-flow reactor
Description : What is the Thiele modulus of the solid catalysed first order reaction as shown in the bellow figure, if the pore diffusion offers negligible resistance to reaction? (A) < 5 (B) < 0.5 (C) > 1 (D) 5
Last Answer : (B) < 0.5
Description : In solid catalysed reactions the diffusional effects are more likely to affect the overall rate of reaction for (A) Fast reactions in catalyst of small pore diameter (B) Fast reaction in catalyst ... reactions in catalyst of small pore diameter (D) Slow reactions in catalyst of large pore diameter
Last Answer : (C) Slow reactions in catalyst of small pore diameter
Description : If pore diffusion is the controlling step in a solid catalysed reaction, the catalyst (A) Porosity is very important (B) Porosity is of less importance (C) Internal surface area is utilised efficiently (D) None of these
Last Answer : (B) Porosity is of less importance
Description : 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 (ke ff) is given by (A) ke ff = k + kg ( ... + kg )/2 (C) ke ff = (kkg ) 1/2 (D) 1/ke ff = 1/k + 1/kg
Last Answer : (D) 1/ke ff = 1/k + 1/kg
Description : For reactions in parallel viz A → P (desired product) and A → Q (unwanted product), if the order of the desired reaction is higher than that of the undesired reaction, a (A) Batch reactor is preferred over a ... a single CSTR for high yield (C) Both (A) and (B) (D) Single CSTR is the most suitable
Last Answer : (C) Both (A) and (B)