CRE section 2

Question 1

When the density of the rxn mixture is constant, the ratio of the mean residence time to space time is

Answer 1

1

Question 2

In an ideal tubular flow reactor,

Answer 2

All abc

Question 3

At a given value of

Question 4

controlling step in a highly temperature sensitive fluid-solid non catalytic rxn

Answer 4

chemical rxn

Question 5

autothermal reactor is

Answer 5

completely self-supporting in its thermal

Question 6

rate constant of a first order rxn depends on

Answer 6

temperature

Question 7

a rxn in which one of the product of rxn acts as a catalyst

Answer 7

autocatalytic

Question 8

ratio of volume of mixed reqctor to the volume of PFR for zero order rxn is

Answer 8

1

Question 9

which favor the reverse rxn in a chemical equilibrium rxn

Answer 9

increasing the concentration of one or more of the products

Question 10

conversion increases with increase in temperature in case of an

Answer 10

reversible endothermic

Question 11

effective diffusivity in a catalyst pellet is related to molecular diffusivity and knudsen diffusivity as ___

Answer 11

1/DE = 1/DN + 1/DK

Question 12

photochemical rxn is

Answer 12

initiated by light

Question 13

wrong statement (continuous flow reactor)

Answer 13

uniform conc cannot be maintained throughout the vessel even in a well agitated system

Question 14

there is a exchange if heat with the surrounding with sizeable temperature variation

Answer 14

non-adiabatic

Question 15

unreqcted core model represents the rxn involving

Answer 15

roasting of sulphide ores

Question 16

for a vapor phase catalytic rxn which follows Ridel Mechanism, the rate if rxn is

Question 17

if a solid non-catalytic rxn occurs at very high temperatures, the rate controlling step is __

Answer 17

film diffusion

Question 18

units of frequency factor in arrhenius equation

Answer 18

the same of the rate constant

Question 19

not a chemical step in a fluid solid catalytic

Answer 19

none of these

Question 20

for a series of rxn having k1&laquo_space;k2, the rxn system can be approximated as

Question 21

K1 K2 and K3 are equilibrium constant for the following rxn, the they are related as

Answer 21

K3 = K1.K2

Question 22

the rxn does not decrease appreciably as the rxn proceeds

Answer 22

auto catalytic

Question 23

for nearly isothermal operation involving large rxn time in a liquid phase rxn, the most suitable reactor is

Answer 23

stirred tank

Question 24

what is the thiele modulus of the solid catalysed forst order rxn if the pore diffusion offers negligible resistance to rxn

Answer 24

< 0.5

Question 25

BET method can be used to determine the ___ of porous

Answer 25

surface area

Question 26

rate constant for a first order rxn does not depend upon rxn time, extent of rxn and the initial conc of reactant: given (100gn to 50gm to reduce from 2gm to 1gm) , the order of rxn is

Answer 26

1

Question 27

which of the following is a independent variable for a batch tank reqctor with uniform concentration and temperature

Answer 27

time

Question 28

for rxn in parallel viz A --> P and A -->Q, if the order the desired rxn is higher than that if the desired rxn, a

Answer 28

both a and b batch is oreferred over single cstr, tubular is preferred over single cstr

Question 29

for a gaseous phase rxn, rate of rxn is equal to K.CA,CB. if the volume of the reqctor is auddenly reduced to 1/4th kf initial volume, the rate of rxn compared to the origial rate will be

Answer 29

16 times

Question 30

in a reversible chemical rxn having two reactants in equilibrium, if the conc of the reactant are doubled, then the equilibrium constant is __

Answer 30

remain the same

Question 31

the equilibrium constant of a catalytic chemical rxn ___ due to catalyst

Answer 31

remains unaffected

Question 32

rate constant if chemical rxn increases by increasing the

Answer 32

temperature

Question 33

the catalytic activity of enzymes is due to capacity to lower the

Answer 33

activation

Question 34

a first order rxn requires two unequal sized cstr, which gives higher yield

Answer 34

either of a and b large followed by small small followed by large

Question 35

correct statement

Answer 35

lower temperature favors the rxn of lower activation energy

Question 36

effect if increasing pressure on the gaseous equilibrium of the rxn 2x+3y <--> 3x+2y indicates that

Answer 36

a pressure has no effect

Question 37

if in the gasous rxn, N2O4 <--> 2NO2, x is the part of N2O4 which dissociates, the number of molecules at equilibrium will be

Answer 37

1 + x

Question 38

batch reactor is characterized by

Answer 38

variation in extent of rxn and properties

Question 39

when a catalyst increases the rate of forward rxn, the value if rate constant __

Answer 39

increase

Question 40

rate determining step in a reaction consisting of a number of steps in series is ___ step

Answer 40

slowest

Question 41

rate if chemical rxn is almost doubled for every 10C rise in temperature, the rate will increase ____ times

Answer 41

512

Question 42

a catalyst in chemical rxn ___ free energy change in the rxn

Answer 42

either a and b, depends on the type of catalyst

Question 43

signal normally used to study non ideal flow by stimulus response techniques is ___ input

Answer 43

both a and b pulse step

Question 44

when all the limiting reactant is consumed, the operational umyield ___ relative yield

Answer 44

equals

Question 45

half life period of first order rxn

Answer 45

independent on initial concentration of the reactants

Question 46

the catalyst in a second order reversible rxn increases the rate of forward rxn and

Answer 46

backward rxn equally

Question 47

catakyst carrier

Answer 47

provide large surface area with a small amount of active material

Question 48

for the liquid phase zero order irreversible rxn A->B, the concersion of A in a CStR is found to be 0.3 at a space velocity of 0.1 min-1. what will be the conversion kf a PFR with a space velocity of 0.2 min-1?

Answer 48

0.6

Question 49

a high soace velocity means that a given

Answer 49

both a and b large followed rxn can be accomplished with small reactor conversion can be obtained with a high feed rate

Question 50

in flow reactors, the performance equation interrelate the rate of rxn to the

Answer 50

all abc feed rate reactor volume extent of rxn