1443 + Mcqs in Chemical Reaction Engineering Page 10 McqOptions

451.	/_What is the unit of the rate constant in a chemical reaction in which 10% of the reactant decomposes in one hour, 20% in two hours, 30% in three hours and so on??
A.	Litre/mole.second
B.	Moles/litre.second
C.	Litre/mole
D.	Litre/second
Answer» B. Moles/litre.second

Discussion

452.	/_The equilibrium constant K of a chemical reaction depends on?
A.	Temperature only
B.	Pressure only
C.	Temperature and pressure
D.	Ratio of reactants
Answer» B. Pressure only

Discussion

453.	/_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
Answer» B. Gain a proton

Discussion

454.	/_Fluidised bed reactor is characterised by?
A.	Uniformity of temperature
B.	Comparatively smaller equipment
C.	Very small pressure drop
D.	Absence of continuous catalyst regeneration facility
Answer» B. Comparatively smaller equipment

Discussion

455.	/_Semibatch reactor is preferred, when a/an?
A.	A highly exothermic reaction is to be controlled
B.	Undersirable side reaction (at high concentration of one of the reactants) is to be avoided
C.	A gas is to be reacted with liquid (e.g. hydrogenation of fat)
D.	All of the above
Answer» E.

Discussion

456.	/_In the reversible reaction of the type, A + B ‚Äö√°√£ AB, in general?
A.	Both forward and backward reactions will be exothermic
B.	Neither of the reactions will be en-dothermic
C.	The combination reaction will be exothermic, while the dissociation reaction will be endothermic
D.	The combination reaction will be endothermic, while the dissociation reaction will be exothermic
Answer» D. The combination reaction will be endothermic, while the dissociation reaction will be exothermic

Discussion

457.	/_Variables affecting the rate of homogeneous reactions are?
A.	Pressure and temperature only
B.	Temperature and composition only
C.	Pressure and composition only
D.	Pressure, temperature and composition
Answer» E.

Discussion

458.	/_Arrhenious equation represents graphically the variation between the __________ and temperature.?
A.	Rate of reaction
B.	Frequency factor
C.	Rate constant
D.	Activation energy
Answer» D. Activation energy

Discussion

459.	/_The half life period of a first order reaction is?
A.	Always the same irrespective of the reaction
B.	Dependent on initial concentration of the reactants
C.	Proportional to the initial concentration of reactants
D.	Half the specific rate constant
Answer» C. Proportional to the initial concentration of reactants

Discussion

460.	/_Reverse reaction in a chemical equilibrium is favoured by the?
A.	Removal of one of the products regularly
B.	Increase in the concentration of oneof the products
C.	Increase in the concentration of one of the reactants
D.	None of these
Answer» C. Increase in the concentration of one of the reactants

Discussion

461.	/_Which of the following will favour the reverse reaction in a chemical equilibrium reaction??
A.	Increasing the concentration of one of the reactants
B.	Increasing the concentration of one or more of the products
C.	Removal of at least one of the products at regular interval
D.	None of these
Answer» C. Removal of at least one of the products at regular interval

Discussion

462.	/_Fluid flow in a real packed bed can be approximated as __________ model.?
A.	Plug flow
B.	Dispersion
C.	Mixed flow
D.	Tank in series
Answer» C. Mixed flow

Discussion

463.	/_The synthesis of proteins and metabolism in biological objects occur in the presence of biocatalyst called?
A.	A ferment or an enzyme
B.	Haemoglobin
C.	Fungi
D.	None of these
Answer» D. None of these

Discussion

464.	/_The knowledge of initial concentration and rate constant is necessary to determine the half life time of a reaction of __________ order.?
A.	Zero
B.	First
C.	Second
D.	None of these
Answer» D. None of these

Discussion

465.	/___________ is the controlling step in a highly temperature sensitive fluid-solid non-catalytic reaction.?
A.	Gas film diffusion
B.	Ash diffusion
C.	Chemical reaction
D.	None of these
Answer» D. None of these

Discussion

466.	/_When the density of the reaction mixture is constant in a chemical reaction, the ratio of the mean residence time to space time is?
A.	> 1
B.	< 1
C.	1
D.	0
Answer» D. 0

Discussion

467.	/_"A spherical porous catalyst particle of radius R is subjected to reactant A which reacts to form B by a zero order surface reaction A ‚Äö√ú√≠ B. Film mass transfer resistance is negligible and pore diffusion of A is rate controlling. The effectiveness factor of the catalyst is reported as 7/8. Which of the following statement is true?A. Inner catalyst core of radius R/8 does not participate in reaction."?
A.	Inner catalyst core of radius R/8 does not participate in reaction
B.	Inner catalyst core of radius R/2 does not participate in reaction
C.	Inner catalyst core of radius 7R/8 does not participate in reaction
D.	Ffectiveness factor for a zero order reaction can not be 7/8 as it must always be 1
Answer» B. Inner catalyst core of radius R/2 does not participate in reaction

Discussion

468.	/_The sequence in which three CSTR's of volumes 5, 10 and 15 m¬¨‚â• will be connected in series to obtain the maximum production in a second order irreversible reaction is?
A.	15, 10, 5
B.	5, 10, 15
C.	10, 5, 15
D.	10, 15, 5
Answer» B. 5, 10, 15

Discussion

469.	/_A space time of 3 hours for a flow reactor means that?
A.	The time required to process one reactor volume of feed (measured at specified conditions) is 3 hours
B.	Three reactor volumes of feed can be processed every hour
C.	It takes three hours to dump the entire volume of the reactor with feed
D.	Conversion is cent per cent after three hours
Answer» B. Three reactor volumes of feed can be processed every hour

Discussion

470.	/_Recycling back of outlet stream to the reactor from an ideal CSTR carrying out a first order liquid phase reaction will result in __________ in conversion.?
A.	Decrease
B.	Increase
C.	No change
D.	Either A or B, depends on the type of reaction
Answer» D. Either A or B, depends on the type of reaction

Discussion

471.	/_If a solid-gas non-catalytic reaction occurs at very high temperature, the rate controlling step is the __________ diffusion.?
A.	Film
B.	Ash layer
C.	Pore
D.	None of these
Answer» B. Ash layer

Discussion

472.	/_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
Answer» C. Plug flow

Discussion

473.	/_What is the value of 'n' if the reaction rate of the chemical reaction A ‚Äö√ú√≠ B, is proportional to CAn and it is found that the reaction rate triples, when the concentration of 'A' is increased 9 times ??
A.	1/2
B.	1/3
C.	1/9
D.	3
Answer» B. 1/3

Discussion

474.	/_A photochemical reaction is __________ light.?
A.	Initiated by
B.	Accompanied with emission of
C.	Catalysed by
D.	Used to convert heat energy into
Answer» B. Accompanied with emission of

Discussion

475.	/_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 reactor decreases with order
C.	Reactor size is independent of the type of flow
D.	Density variation during reaction affects design
Answer» B. Ratio of the volume of the mixed reactor to that of the plug-flow reactor decreases with order

Discussion

476.	/_A stirred tank reactor compared to tubular-flow reactor provides?
A.	More uniform operating conditions
B.	Permits operation at the optimum temperature for a long reaction time
C.	Higher overall selectivity for a first order consecutive reaction
D.	All of the above
Answer» E.

Discussion

477.	/_An irreversible first order reaction is being carried out in a CSTR and PFR of same volume. The liquid flow rates are same. The relative conversion will?
A.	Be more in CSTR than in PFR
B.	Be more in PFR than in CSTR
C.	Be same in both cases
D.	Depend on the temperature
Answer» C. Be same in both cases

Discussion

478.	/_A first order reaction requires two equal sized CSTR. The conversion is?
A.	Less when they are connected in series
B.	More when they are connected in series
C.	More when they are connected in parallel
D.	Same whether they are connected in series or in parallel
Answer» C. More when they are connected in parallel

Discussion

479.	/_A reactor is generally termed as an autoclave, when it is a?
A.	High pressure batch reactor
B.	Atmospheric pressure tank reactor
C.	High pressure tubular reactor
D.	Atmospheric pressure CSTR
Answer» B. Atmospheric pressure tank reactor

Discussion

480.	/_Study of chemical kinetics is the easiest in the case of __________ reactions.?
A.	Irreversible
B.	Reversible
C.	Surface
D.	Side
Answer» B. Reversible

Discussion

481.	/_The time needed to achieve the same fractional conversion for particles of different sizes (d) when chemical reaction controls, is proportional to?
A.	D
B.	‚Äö√ √∂d
C.	D1.5
D.	D2
Answer» B. ‚Äö√ √∂d

Discussion

482.	/_For identical flow rate and feed composition, X plug flow reactors (PER) in series with a total volume V gives the same conversion as single?
A.	CSTR of volume V
B.	PFR of volume V
C.	CSTR of volume V/X
D.	PFR of volume V/X
Answer» C. CSTR of volume V/X

Discussion

483.	/_For an ideal gas mixture undergoing a reversible gaseous phase chemical reaction, the equilibrium constant?
A.	Is independent of pressure
B.	Increases with pressure
C.	Decreases with pressure
D.	Increases /decreases with pressure depending on the stoichiometric co-efficients of the reaction
Answer» C. Decreases with pressure

Discussion

484.	/_The molecularity and the order of reaction respectively, for the hydrolysis of methyl acetate in presence of acids are?
A.	2 & 1
B.	11 & 2
C.	2 && 2
D.	1 & 1
Answer» B. 11 & 2

Discussion

485.	/_For a heterogeneous catalytic reaction?
A.	Free energy of activation is lowered in the presence of catalyst, which remains unchanged at the end of reaction
B.	A relatively small amount of catalyst can cause the conversion of large amount of reactants which does not mean that catalyst concentration is important
C.	The catalyst does not form an intermediate complex with the reactant
D.	The surface of the catalyst does not play an important role during reaction
Answer» B. A relatively small amount of catalyst can cause the conversion of large amount of reactants which does not mean that catalyst concentration is important

Discussion

486.	/_The rate constant of a reaction depends on the?
A.	Initial concentration of reactants
B.	Time of reaction
C.	Temperature of the system
D.	Extent of reaction
Answer» D. Extent of reaction

Discussion

487.	/_A chemical reaction is of zero order, when the reaction rate is (where, CA = concentration of reactant)?
A.	‚Äö√ √π CA
B.	‚Äö√ √π 1/CA
C.	Independent of temperature
D.	None of these
Answer» E.

Discussion

488.	%_A catalyst promoter_%
A.	Improves the activity of a catalyst
B.	Acts as a catalyst support
C.	Itself has very high activity
D.	All of the above
Answer» B. Acts as a catalyst support

Discussion

489.	%_A first order reaction requires two unequal sized CSTR. Which of the following gives higher yield ?_%
A.	Large reactor followed by smaller one
B.	Smaller reactor followed by larger one
C.	Either of the arrangement A or B will give the same yield
D.	Data insufficient, can
Answer» D. Data insufficient, can

Discussion

490.	%_Most important characteristics of gas-liquid reactors are the_%
A.	Specific inter-facial area
B.	Liquid hold-up
C.	Both A and B
D.	None of these
Answer» D. None of these

Discussion

491.	%_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
Answer» C. Both A and B

Discussion

492.	%_Calcination reaction of limestone (CaCO‚Äö√á√â ‚Äö√ú√≠ CaO + CO‚Äö√á√á) goes to completion in the rotary kiln, because_%
A.	CaO is not dissociated
B.	CO‚Äö√á√á escapes continuously
C.	Of high calcination temperature
D.	CaO is more stable than CaCO‚Äö√á√â
Answer» C. Of high calcination temperature

Discussion

493.	%_In the fluid catalytic cracker (FCC), the cracking reaction is __________ (i) and the regeneration is ____________ (ii)_%
A.	(i) exothermic (ii) endothermic
B.	(i) exothermic (ii) exothermic
C.	(i) endothermic (ii) enodthermic
D.	(i) endothermic (ii) exothermic
Answer» E.

Discussion

494.	%_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.	‚Äö√ √ª
B.	0
C.	1
D.	> 1
Answer» D. > 1

Discussion

495.	%_The equilibrium constant of a catalytic chemical reaction __________ due to the presence of a catalyst._%
A.	Increases
B.	Decreases
C.	Remains unaffected
D.	Unpredictable from the data
Answer» D. Unpredictable from the data

Discussion

496.	%_Collision theory gives the rate constant for bimolecular reaction as_%
A.	K ≈í¬± ‚Äö√ √∂T.e-E/RT
B.	K ≈í¬± eE/RT
C.	K ≈í¬± e-E/RT
D.	None of these
Answer» D. None of these

Discussion

497.	%_The excess energy of the reactants required to dissociate into products is known as the __________ energy._%
A.	Thermal
B.	Activation
C.	Threshold
D.	Binding
Answer» C. Threshold

Discussion

498.	%_Which of the following curves shows the effect of temperature on the extent of gas-solid adsorption at a given pressure?_%
A.	Langmuir adsorption isotherm
B.	Adsorption isobar
C.	Freundlich adsorption isotherm
D.	None of these
Answer» C. Freundlich adsorption isotherm

Discussion

499.	%_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
Answer» C. Stirred tank reactor

Discussion

500.	%_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
Answer» E.

Discussion

Explore topic-wise MCQs in Chemical Engineering.

*/*_What is the unit of the rate constant in a chemical reaction in which 10% of the reactant decomposes in one hour, 20% in two hours, 30% in three hours and so on??

*/*_The equilibrium constant K of a chemical reaction depends on?

*/*_A reaction which is catalysed by an acid is also catalysed by any substance, which has a tendency to?

*/*_Fluidised bed reactor is characterised by?

*/*_Semibatch reactor is preferred, when a/an?

*/*_In the reversible reaction of the type, A + B ‚Äö√°√£ AB, in general?

*/*_Variables affecting the rate of homogeneous reactions are?

*/*_Arrhenious equation represents graphically the variation between the __________ and temperature.?

*/*_The half life period of a first order reaction is?

*/*_Reverse reaction in a chemical equilibrium is favoured by the?

*/*_Which of the following will favour the reverse reaction in a chemical equilibrium reaction??

*/*_Fluid flow in a real packed bed can be approximated as __________ model.?

*/*_The synthesis of proteins and metabolism in biological objects occur in the presence of biocatalyst called?

*/*_The knowledge of initial concentration and rate constant is necessary to determine the half life time of a reaction of __________ order.?

*/*___________ is the controlling step in a highly temperature sensitive fluid-solid non-catalytic reaction.?

*/*_When the density of the reaction mixture is constant in a chemical reaction, the ratio of the mean residence time to space time is?

*/*_The sequence in which three CSTR's of volumes 5, 10 and 15 m¬¨‚â• will be connected in series to obtain the maximum production in a second order irreversible reaction is?

*/*_A space time of 3 hours for a flow reactor means that?

*/*_Recycling back of outlet stream to the reactor from an ideal CSTR carrying out a first order liquid phase reaction will result in __________ in conversion.?

*/*_If a solid-gas non-catalytic reaction occurs at very high temperature, the rate controlling step is the __________ diffusion.?

*/*_For a fluidised bed reactor, the most suitable/relevant model is a __________ model.?

*/*_What is the value of 'n' if the reaction rate of the chemical reaction A ‚Äö√ú√≠ B, is proportional to CAn and it is found that the reaction rate triples, when the concentration of 'A' is increased 9 times ??

*/*_A photochemical reaction is __________ light.?

*/*_For all positive reaction orders for a particular duty,?

*/*_A stirred tank reactor compared to tubular-flow reactor provides?

*/*_An irreversible first order reaction is being carried out in a CSTR and PFR of same volume. The liquid flow rates are same. The relative conversion will?

*/*_A first order reaction requires two equal sized CSTR. The conversion is?

*/*_A reactor is generally termed as an autoclave, when it is a?

*/*_Study of chemical kinetics is the easiest in the case of __________ reactions.?

*/*_The time needed to achieve the same fractional conversion for particles of different sizes (d) when chemical reaction controls, is proportional to?

*/*_For identical flow rate and feed composition, X plug flow reactors (PER) in series with a total volume V gives the same conversion as single?

*/*_For an ideal gas mixture undergoing a reversible gaseous phase chemical reaction, the equilibrium constant?

*/*_The molecularity and the order of reaction respectively, for the hydrolysis of methyl acetate in presence of acids are?

*/*_For a heterogeneous catalytic reaction?

*/*_The rate constant of a reaction depends on the?

*/*_A chemical reaction is of zero order, when the reaction rate is (where, CA = concentration of reactant)?

%_A catalyst promoter_%

%_A first order reaction requires two unequal sized CSTR. Which of the following gives higher yield ?_%

%_Most important characteristics of gas-liquid reactors are the_%

%_For a solid catalysed chemical reaction, the effectiveness of solid catalyst depends upon the __________ adsorption._%

%_Calcination reaction of limestone (CaCO‚Äö√á√â ‚Äö√ú√≠ CaO + CO‚Äö√á√á) goes to completion in the rotary kiln, because_%

%_In the fluid catalytic cracker (FCC), the cracking reaction is __________ (i) and the regeneration is ____________ (ii)_%

%_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_%

%_The equilibrium constant of a catalytic chemical reaction __________ due to the presence of a catalyst._%

%_Collision theory gives the rate constant for bimolecular reaction as_%

%_The excess energy of the reactants required to dissociate into products is known as the __________ energy._%

%_Which of the following curves shows the effect of temperature on the extent of gas-solid adsorption at a given pressure?_%

%_Which of the following is the most suitable for very high pressure gas phase reaction?_%

%_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._%

/_What is the unit of the rate constant in a chemical reaction in which 10% of the reactant decomposes in one hour, 20% in two hours, 30% in three hours and so on??

/_The equilibrium constant K of a chemical reaction depends on?

/_A reaction which is catalysed by an acid is also catalysed by any substance, which has a tendency to?

/_Fluidised bed reactor is characterised by?

/_Semibatch reactor is preferred, when a/an?

/_In the reversible reaction of the type, A + B ‚Äö√°√£ AB, in general?

/_Variables affecting the rate of homogeneous reactions are?

/_Arrhenious equation represents graphically the variation between the __________ and temperature.?

/_The half life period of a first order reaction is?

/_Reverse reaction in a chemical equilibrium is favoured by the?

/_Which of the following will favour the reverse reaction in a chemical equilibrium reaction??

/_Fluid flow in a real packed bed can be approximated as __________ model.?

/_The synthesis of proteins and metabolism in biological objects occur in the presence of biocatalyst called?

/_The knowledge of initial concentration and rate constant is necessary to determine the half life time of a reaction of __________ order.?

/___________ is the controlling step in a highly temperature sensitive fluid-solid non-catalytic reaction.?

/_When the density of the reaction mixture is constant in a chemical reaction, the ratio of the mean residence time to space time is?

/_The sequence in which three CSTR's of volumes 5, 10 and 15 m¬¨‚â• will be connected in series to obtain the maximum production in a second order irreversible reaction is?

/_A space time of 3 hours for a flow reactor means that?

/_Recycling back of outlet stream to the reactor from an ideal CSTR carrying out a first order liquid phase reaction will result in __________ in conversion.?

/_If a solid-gas non-catalytic reaction occurs at very high temperature, the rate controlling step is the __________ diffusion.?

/_For a fluidised bed reactor, the most suitable/relevant model is a __________ model.?

/_What is the value of 'n' if the reaction rate of the chemical reaction A ‚Äö√ú√≠ B, is proportional to CAn and it is found that the reaction rate triples, when the concentration of 'A' is increased 9 times ??

/_A photochemical reaction is __________ light.?

/_For all positive reaction orders for a particular duty,?

/_A stirred tank reactor compared to tubular-flow reactor provides?

/_An irreversible first order reaction is being carried out in a CSTR and PFR of same volume. The liquid flow rates are same. The relative conversion will?

/_A first order reaction requires two equal sized CSTR. The conversion is?

/_A reactor is generally termed as an autoclave, when it is a?

/_Study of chemical kinetics is the easiest in the case of __________ reactions.?

/_The time needed to achieve the same fractional conversion for particles of different sizes (d) when chemical reaction controls, is proportional to?

/_For identical flow rate and feed composition, X plug flow reactors (PER) in series with a total volume V gives the same conversion as single?

/_For an ideal gas mixture undergoing a reversible gaseous phase chemical reaction, the equilibrium constant?

/_The molecularity and the order of reaction respectively, for the hydrolysis of methyl acetate in presence of acids are?

/_For a heterogeneous catalytic reaction?

/_The rate constant of a reaction depends on the?

/_A chemical reaction is of zero order, when the reaction rate is (where, CA = concentration of reactant)?

%_In the fluid catalytic cracker (FCC), the cracking reaction is (i) and the regeneration is __ (ii)_%