Integral method for analysing the kinetic data is used%!

For testing specific mechanisms with simple rate expressions

For high conversion in a highly exothermic solid catalysed reaction, use a __________ bed reactor.%!

Fixed bed reactor followed by a fluidised

Fluidised bed reactor followed by a fixed

Fixed bed reactor followed by a fluidised

*$_For a tubular reactor with space time '≈ì√ë' and residence time '≈í‚àè', the following statement holds good.?

≈ì√ë = ≈í‚àè , for a non-isothermal reactor

≈ì√ë and ≈í‚àè are always equal

≈ì√ë = ≈í‚àè , when the fluid density changes in the reactor

≈ì√ë = ≈í‚àè , for an isothermic tubular reactor in which the density of the process fluid is constant

≈ì√ë = ≈í‚àè , for a non-isothermal reactor

*$_Transition state theory gives the rate constant as?

K ≈í¬± ‚Äö√ √∂T . e-E/RT

*$_Considering the endotheomic dissociation of CaCO‚Äö√á√â in a closed vessel (CaCO‚Äö√á√â ‚Äö√°√£ CaO + CO‚Äö√á√á), the pressure of CO‚Äö√á√á increases, if?

An inert gas is pumped keeping the temperature constant

*$_Chemical reaction rate of a component depends upon the?

Composition of the component only

*$_The rate expression for a heterogenous 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 ≈í√ÆHR and ≈í√ÆHA are the activation energies of adsorption of R and A)?

E + ≈í√ÆHA - ≈í√ÆHR

*$_Rate determining step in a reaction consisting of a number of steps in series is the __________ step.?

Data insufficient; can't be predicted

*$_For multiple reactions, the flow pattern within the vessel affects the?

Distribution of reaction products

*$_Exothermic reactions are best carried out in?

A plug flow reactor followed by CSTR

CSTR followed by a plug flow reactor

*$_In which of the following reactions, thee-quilibrium will shift to the right, if the total pressure is increased??

N‚Äö√á√áO‚Äö√á√ë ‚Äö√°√£ 2 NO‚Äö√á√á

H‚Äö√á√á + Cl‚Äö√á√á ‚Äö√°√£ 2HCl

N‚Äö√á√á + O‚Äö√á√á ‚Äö√°√£ 2NO

N‚Äö√á√áO‚Äö√á√ë ‚Äö√°√£ 2 NO‚Äö√á√á

H‚Äö√á√á + I‚Äö√á√á ‚Äö√°√£ 2HI

*/*_Integral method for analysing the kinetic data is used?

For testing specific mechanisms with simple rate expressions

*/*_For high conversion in a highly exothermic solid catalysed reaction, use a __________ bed reactor.?

Fixed bed reactor followed by a fluidised

Fluidised bed reactor followed by a fixed

Fixed bed reactor followed by a fluidised

*/*_The increase in the rate of reaction with temperature is due to?

Increase in the average kinetic energy of the reacting molecules

Increase in the number of effective collisions

Increase in the average kinetic energy of the reacting molecules

Is capable of reacting with any one of the reactants

Lowers the activation energy of reacting molecules

Is capable of reacting with any one of the reactants

Can not be recovered chemically unchanged at the end of a chemical reaction

*/*_A high space velocity means that a given?

Reaction can be accomplished with small reactor

Conversion can be obtained with a high feed rate

*/*_Photochemical reaction rate does not depend significantly on temperature, because?

The energy of reacting molecules exceeds the activation energy by absorption of light

*/*_A chemical reaction, A ‚Äö√ú√≠ 3B, is conducted in a constant pressure vessel. Starting with pure A, the volume of the reaction mixture increases 3 times in 6 minutes. The fractional conversion is?

Data insufficient, can't be predicted

1443 + Mcqs in Chemical Reaction Engineering Page 9 McqOptions

401.	Integral method for analysing the kinetic data is used%!
A.	When the data are scattered
B.	For testing specific mechanisms with simple rate expressions
C.	Both A and B
D.	None of these
Answer» D. None of these

Discussion

402.	The reactions with low activation energy are%!
A.	Always spantaneous
B.	Slow
C.	Fast
D.	Non-spontaneous
Answer» D. Non-spontaneous

Discussion

403.	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
Answer» C. Fixed bed reactor followed by a fluidised

Discussion

404.	Kinetics of a solid catalysed reaction can best be studied in a __________ reactor.%!
A.	Batch
B.	Plug-flow
C.	Mixed
D.	None of these
Answer» D. None of these

Discussion

405.	*$_For a tubular reactor with space time '≈ì√ë' and residence time '≈í‚àè', the following statement holds good.?
A.	≈ì√ë and ≈í‚àè are always equal
B.	≈ì√ë = ≈í‚àè , when the fluid density changes in the reactor
C.	≈ì√ë = ≈í‚àè , for an isothermic tubular reactor in which the density of the process fluid is constant
D.	≈ì√ë = ≈í‚àè , for a non-isothermal reactor
Answer» D. ≈ì√ë = ≈í‚àè , for a non-isothermal reactor

Discussion

406.	*$_The enzyme which can catalyse the conversion of glucose to ethyl alcohol is?
A.	Invertase
B.	Maltase
C.	Diastase
D.	Zymase
Answer» E.

Discussion

407.	*$_When a catalyst increases the rate of forward reaction, the value of rate constant?
A.	Increases
B.	Decreases
C.	Remain same
D.	Becomes infinite
Answer» B. Decreases

Discussion

408.	*$_For every 10¬¨‚àûC rise in temperature, the rate of chemical reaction doubles. When the temperature is increased from 30 to 70¬¨‚àûC, the rate of reaction increases __________ times.?
A.	8
B.	12
C.	16
D.	32
Answer» D. 32

Discussion

409.	*$___________ explains the mechanism of catalysis.?
A.	Activated complex theory
B.	Collision theory
C.	Thermodynamics
D.	None of these
Answer» B. Collision theory

Discussion

410.	*$_Vegetable oils are hydrogenated in a __________ reactor.?
A.	Slurry
B.	Plug flow
C.	Homogeneous catalytic
D.	None of these
Answer» B. Plug flow

Discussion

411.	*$_From Arhenius 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/¬¨‚àûK
C.	¬¨‚àûK
D.	K cal. ¬¨‚àûK
Answer» D. K cal. ¬¨‚àûK

Discussion

412.	*$_The vessel dispersion number (D/≈í¬∫L) for plug flow is?
A.	0
B.	500
C.	750
D.	‚Äö√ √ª
Answer» B. 500

Discussion

413.	*$_Radioactive decay follows __________ order kinetics.?
A.	First
B.	Second
C.	Third
D.	Zero
Answer» B. Second

Discussion

414.	*$_Transition state theory gives the rate constant as?
A.	K ≈í¬± e-E/RT
B.	K ≈í¬± eE/RT
C.	K ≈í¬± T . e-E/RT
D.	K ≈í¬± ‚Äö√ √∂T . e-E/RT
Answer» D. K ≈í¬± ‚Äö√ √∂T . e-E/RT

Discussion

415.	*$_Considering the endotheomic dissociation of CaCO‚Äö√á√â in a closed vessel (CaCO‚Äö√á√â ‚Äö√°√£ CaO + CO‚Äö√á√á), the pressure of CO‚Äö√á√á increases, if?
A.	A catalyst is added
B.	The temperature is increased
C.	An inert gas is pumped keeping the temperature constant
D.	None of these
Answer» C. An inert gas is pumped keeping the temperature constant

Discussion

416.	*$_In a CSTR __________ varies with time.?
A.	Reaction rate
B.	Concentration
C.	Both A & B
D.	Neither A nor B
Answer» E.

Discussion

417.	*$_Chemical reaction rate of a component depends upon the?
A.	Composition of the component only
B.	Temperature of the system
C.	Pressure of the system
D.	All of the above
Answer» E.

Discussion

418.	*$_The rate expression for a heterogenous 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 ≈í√ÆHR and ≈í√ÆHA are the activation energies of adsorption of R and A)?
A.	E
B.	E + ≈í√ÆHA
C.	E + ≈í√ÆHA - ≈í√ÆHR
D.	≈í√ÆHA + ≈í√ÆHR
Answer» D. ≈í√ÆHA + ≈í√ÆHR

Discussion

419.	*$_A multiple reaction may be classified as a __________ reaction.?
A.	Consecutive or side
B.	Parallel or side
C.	Mixed
D.	All of the above
Answer» E.

Discussion

420.	*$_Rate determining step in a reaction consisting of a number of steps in series is the __________ step.?
A.	Fastest
B.	Slowest
C.	Intermediate
D.	Data insufficient; can't be predicted
Answer» C. Intermediate

Discussion

421.	*$_Higher free energy of activation of a chemical reaction (at a given temperature) implies?
A.	Slower rate of reaction
B.	Higher rate of reaction
C.	Higher equilibrium conversion
D.	Both B and C
Answer» B. Higher rate of reaction

Discussion

422.	*$_For multiple reactions, the flow pattern within the vessel affects the?
A.	Size requirement
B.	Distribution of reaction products
C.	Both A and B
D.	Neither A nor B
Answer» D. Neither A nor B

Discussion

423.	*$_For the chemical reaction P ‚Äö√ú√≠ Q, it is found that the rate of reaction doubles as the concentration of 'P' is doubled. If the reaction rate is proportional to Cpn, then what is the value of 'n' for this chemical reaction?
A.	1
B.	2
C.	3
D.	0
Answer» B. 2

Discussion

424.	*$_For a gaseous phase reaction, rate of reaction is equal to K. CA . CB. If the volume of the reactor is suddenly reduced to l/4th of its initial volume, then the rate of reaction compared to the original rate will be __________ times.?
A.	8
B.	16
C.	1/8
D.	1/16
Answer» C. 1/8

Discussion

425.	*$_Exothermic reactions are best carried out in?
A.	A CSTR
B.	CSTR in series
C.	A plug flow reactor followed by CSTR
D.	CSTR followed by a plug flow reactor
Answer» E.

Discussion

426.	*$_With an increase in pressure in gaseous phase chemical reactions, the fractional conversion __________ when the number of moles decreases.?
A.	Increases
B.	Decreases
C.	Remains unaffected
D.	Unpredictable from the data
Answer» B. Decreases

Discussion

427.	*$_In which of the following reactions, thee-quilibrium will shift to the right, if the total pressure is increased??
A.	H‚Äö√á√á + Cl‚Äö√á√á ‚Äö√°√£ 2HCl
B.	N‚Äö√á√á + O‚Äö√á√á ‚Äö√°√£ 2NO
C.	N‚Äö√á√áO‚Äö√á√ë ‚Äö√°√£ 2 NO‚Äö√á√á
D.	H‚Äö√á√á + I‚Äö√á√á ‚Äö√°√£ 2HI
Answer» C. N‚Äö√á√áO‚Äö√á√ë ‚Äö√°√£ 2 NO‚Äö√á√á

Discussion

428.	/_The reactions with low activation energy are?
A.	Always spantaneous
B.	Slow
C.	Fast
D.	Non-spontaneous
Answer» D. Non-spontaneous

Discussion

429.	/_Integral method for analysing the kinetic data is used?
A.	When the data are scattered
B.	For testing specific mechanisms with simple rate expressions
C.	Both A and B
D.	None of these
Answer» D. None of these

Discussion

430.	/_Kinetics of a solid catalysed reaction can best be studied in a __________ reactor.?
A.	Batch
B.	Plug-flow
C.	Mixed
D.	None of these
Answer» D. None of these

Discussion

431.	/_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
Answer» C. Fixed bed reactor followed by a fluidised

Discussion

432.	/_A CSTR is to be designed in which an exothermic liquid phase first order reaction of the type, A ‚Äö√ú√≠ 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/m¬¨‚â• ; XA = 0.5; Feed temperature = reactor temperature = 40¬¨‚àûC. Rate constant at 40¬¨‚àûC = 1 min‚Äö√Ö¬™¬¨œÄ ; (≈í√ÆH) = - 40kJ/mole; ≈ì√Ö = 1000kg/m¬¨‚â• CP = 4 J/gm.¬¨‚àûC ; q = 10‚Äö√Ö¬™¬¨‚â• m¬¨‚â•/min (≈ì√Ö and CP are same for the reactant and product streams). The amount of heat to be removed is?
A.	2/3 kW
B.	1kW
C.	5/3 kW
D.	4kW
Answer» D. 4kW

Discussion

433.	/_When the reaction occurs in the diffusion controlled region, the apparent activation energy as measured is only __________ the true value.?
A.	Twice
B.	Half
C.	Equal
D.	None of these
Answer» C. Equal

Discussion

434.	/_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.	8
Answer» C. 6

Discussion

435.	/_Autocatalytic reactions are best carried out in a?
A.	CSTR
B.	CSTR in series
C.	Plug flow reactor
D.	Recycle reactor
Answer» E.

Discussion

436.	/_For the non-catalytic reaction of particles with surrounding fluid, the time needed to achieve the same fractional conversion for particles of different but unchanging sizes is proportional to the square of particle diameter, when the __________ is the controlling resistance.?
A.	Film diffusion
B.	Diffusion through ash layer
C.	Chemical reaction
D.	Either A, B or C
Answer» C. Chemical reaction

Discussion

437.	/_Equilibrium of a chemical reaction as viewed by kinetics is a __________ state.?
A.	Dynamic steady
B.	Static steady
C.	Dynamic unsteady
D.	None of these
Answer» B. Static steady

Discussion

438.	/_The increase in the rate of reaction with temperature is due to?
A.	Increase in the number of effective collisions
B.	Decrease in activation energy
C.	Increase in the average kinetic energy of the reacting molecules
D.	None of these
Answer» C. Increase in the average kinetic energy of the reacting molecules

Discussion

439.	/_A liquid decomposes by irreversible first order kinetics and the half life period of this reaction is 8 minutes. The time required for 75% conversion of the liquid will be __________ minutes.?
A.	4
B.	8
C.	12
D.	16
Answer» E.

Discussion

440.	/_For the reversible reaction A ‚Äö√°√£ 2B, if the equilibrium constant K is 0.05 mole/litre; starting from initially 2 moles of A and zero moles of B, how many moles will be formed at equilibrium??
A.	0.253
B.	0.338
C.	0.152
D.	0.637
Answer» C. 0.152

Discussion

441.	/_Helium-mercury method can be used to determine the __________ of the catalyst particle.?
A.	Pore volume
B.	Solid density
C.	Porosity
D.	All of the above
Answer» E.

Discussion

442.	/_B.E.T. method can be used to determine the __________ of a porous catalyst.?
A.	Solid density
B.	Pore volume
C.	Surface area
D.	All of the above
Answer» D. All of the above

Discussion

443.	/_A catalyst?
A.	Initiates a reaction
B.	Lowers the activation energy of reacting molecules
C.	Is capable of reacting with any one of the reactants
D.	Can not be recovered chemically unchanged at the end of a chemical reaction
Answer» C. Is capable of reacting with any one of the reactants

Discussion

444.	/_For a __________ order reaction, the units of rate constant and rate of reaction are the same.?
A.	Zero
B.	First
C.	Second
D.	Fractional
Answer» B. First

Discussion

445.	/_A high space velocity means that a given?
A.	Reaction can be accomplished with small reactor
B.	Conversion can be obtained with a high feed rate
C.	Both A and B
D.	None of these
Answer» D. None of these

Discussion

446.	/_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
Answer» C. Plug-flow reactor

Discussion

447.	/_Photochemical reaction rate does not depend significantly on temperature, because?
A.	It is a reversible reaction
B.	It is an exothermic reaction
C.	The energy of reacting molecules exceeds the activation energy by absorption of light
D.	None of these
Answer» D. None of these

Discussion

448.	/_A chemical reaction, A ‚Äö√ú√≠ 3B, is conducted in a constant pressure vessel. Starting with pure A, the volume of the reaction mixture increases 3 times in 6 minutes. The fractional conversion is?
A.	0.33
B.	0.5
C.	1
D.	Data insufficient, can't be predicted
Answer» D. Data insufficient, can't be predicted

Discussion

449.	/_Fractional conversion __________ with increase in pressure for ammonia synthesis reaction i.e., N‚Äö√á√á + 3H‚Äö√á√á ‚Äö√°√£ 2NH‚Äö√á√â.?
A.	Increases
B.	Decreases
C.	Remains unchanged
D.	Unpredictable from the data
Answer» B. Decreases

Discussion

450.	/_When a catalyst increases the rate of chemical reaction, the rate constant?
A.	Decreases
B.	Increases
C.	Remains constant
D.	Becomes infinite
Answer» C. Remains constant

Discussion

Explore topic-wise MCQs in Chemical Engineering.

Integral method for analysing the kinetic data is used%!

The reactions with low activation energy are%!

For high conversion in a highly exothermic solid catalysed reaction, use a __________ bed reactor.%!

Kinetics of a solid catalysed reaction can best be studied in a __________ reactor.%!

*$_For a tubular reactor with space time '≈ì√ë' and residence time '≈í‚àè', the following statement holds good.?

*$_The enzyme which can catalyse the conversion of glucose to ethyl alcohol is?

*$_When a catalyst increases the rate of forward reaction, the value of rate constant?

*$_For every 10¬¨‚àûC rise in temperature, the rate of chemical reaction doubles. When the temperature is increased from 30 to 70¬¨‚àûC, the rate of reaction increases __________ times.?

*$___________ explains the mechanism of catalysis.?

*$_Vegetable oils are hydrogenated in a __________ reactor.?

*$_From Arhenius 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?

*$_The vessel dispersion number (D/≈í¬∫L) for plug flow is?

*$_Radioactive decay follows __________ order kinetics.?

*$_Transition state theory gives the rate constant as?

*$_Considering the endotheomic dissociation of CaCO‚Äö√á√â in a closed vessel (CaCO‚Äö√á√â ‚Äö√°√£ CaO + CO‚Äö√á√á), the pressure of CO‚Äö√á√á increases, if?

*$_In a CSTR __________ varies with time.?

*$_Chemical reaction rate of a component depends upon the?

*$_A multiple reaction may be classified as a __________ reaction.?

*$_Rate determining step in a reaction consisting of a number of steps in series is the __________ step.?

*$_Higher free energy of activation of a chemical reaction (at a given temperature) implies?

*$_For multiple reactions, the flow pattern within the vessel affects the?

*$_For the chemical reaction P ‚Äö√ú√≠ Q, it is found that the rate of reaction doubles as the concentration of 'P' is doubled. If the reaction rate is proportional to Cpn, then what is the value of 'n' for this chemical reaction?

*$_For a gaseous phase reaction, rate of reaction is equal to K. CA . CB. If the volume of the reactor is suddenly reduced to l/4th of its initial volume, then the rate of reaction compared to the original rate will be __________ times.?

*$_Exothermic reactions are best carried out in?

*$_With an increase in pressure in gaseous phase chemical reactions, the fractional conversion __________ when the number of moles decreases.?

*$_In which of the following reactions, thee-quilibrium will shift to the right, if the total pressure is increased??

*/*_The reactions with low activation energy are?

*/*_Integral method for analysing the kinetic data is used?

*/*_Kinetics of a solid catalysed reaction can best be studied in a __________ reactor.?

*/*_For high conversion in a highly exothermic solid catalysed reaction, use a __________ bed reactor.?

*/*_When the reaction occurs in the diffusion controlled region, the apparent activation energy as measured is only __________ the true value.?

*/*_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.?

*/*_Autocatalytic reactions are best carried out in a?

*/*_For the non-catalytic reaction of particles with surrounding fluid, the time needed to achieve the same fractional conversion for particles of different but unchanging sizes is proportional to the square of particle diameter, when the __________ is the controlling resistance.?

*/*_Equilibrium of a chemical reaction as viewed by kinetics is a __________ state.?

*/*_The increase in the rate of reaction with temperature is due to?

*/*_A liquid decomposes by irreversible first order kinetics and the half life period of this reaction is 8 minutes. The time required for 75% conversion of the liquid will be __________ minutes.?

*/*_For the reversible reaction A ‚Äö√°√£ 2B, if the equilibrium constant K is 0.05 mole/litre; starting from initially 2 moles of A and zero moles of B, how many moles will be formed at equilibrium??

*/*_Helium-mercury method can be used to determine the __________ of the catalyst particle.?

*/*_B.E.T. method can be used to determine the __________ of a porous catalyst.?

*/*_A catalyst?

*/*_For a __________ order reaction, the units of rate constant and rate of reaction are the same.?

*/*_A high space velocity means that a given?

*/*_Which of the following is the most suitable for isothermal operation??

*/*_Photochemical reaction rate does not depend significantly on temperature, because?

*/*_A chemical reaction, A ‚Äö√ú√≠ 3B, is conducted in a constant pressure vessel. Starting with pure A, the volume of the reaction mixture increases 3 times in 6 minutes. The fractional conversion is?

*/*_Fractional conversion __________ with increase in pressure for ammonia synthesis reaction i.e., N‚Äö√á√á + 3H‚Äö√á√á ‚Äö√°√£ 2NH‚Äö√á√â.?

*/*_When a catalyst increases the rate of chemical reaction, the rate constant?

/_The reactions with low activation energy are?

/_Integral method for analysing the kinetic data is used?

/_Kinetics of a solid catalysed reaction can best be studied in a __________ reactor.?

/_For high conversion in a highly exothermic solid catalysed reaction, use a __________ bed reactor.?

/_When the reaction occurs in the diffusion controlled region, the apparent activation energy as measured is only __________ the true value.?

/_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.?

/_Autocatalytic reactions are best carried out in a?

/_For the non-catalytic reaction of particles with surrounding fluid, the time needed to achieve the same fractional conversion for particles of different but unchanging sizes is proportional to the square of particle diameter, when the __________ is the controlling resistance.?

/_Equilibrium of a chemical reaction as viewed by kinetics is a __________ state.?

/_The increase in the rate of reaction with temperature is due to?

/_A liquid decomposes by irreversible first order kinetics and the half life period of this reaction is 8 minutes. The time required for 75% conversion of the liquid will be __________ minutes.?

/_For the reversible reaction A ‚Äö√°√£ 2B, if the equilibrium constant K is 0.05 mole/litre; starting from initially 2 moles of A and zero moles of B, how many moles will be formed at equilibrium??

/_Helium-mercury method can be used to determine the __________ of the catalyst particle.?

/_B.E.T. method can be used to determine the __________ of a porous catalyst.?

/_A catalyst?

/_For a __________ order reaction, the units of rate constant and rate of reaction are the same.?

/_A high space velocity means that a given?

/_Which of the following is the most suitable for isothermal operation??

/_Photochemical reaction rate does not depend significantly on temperature, because?

/_A chemical reaction, A ‚Äö√ú√≠ 3B, is conducted in a constant pressure vessel. Starting with pure A, the volume of the reaction mixture increases 3 times in 6 minutes. The fractional conversion is?

/_Fractional conversion __________ with increase in pressure for ammonia synthesis reaction i.e., N‚Äö√á√á + 3H‚Äö√á√á ‚Äö√°√£ 2NH‚Äö√á√â.?

/_When a catalyst increases the rate of chemical reaction, the rate constant?