CRE section 3

Question 1

space velocity

Answer 1

all abc

Question 2

a rxn which is catalyzed by a base is catalyzed by all substances which

Answer 2

gain a proton

Question 3

the rate of chemical rxn A ->B double as the conc of A is doubled. if rate of rxn is proportional to CAn, what is the value of n

Answer 3

1

Question 4

for a homogeneous rxn of nth order, the dimension if the rate constant is given by

Answer 4

concentration^1 - n/time

Question 5

fractional volume change between no conversion and complete conversion for the isothermal gas phase rxn is

Answer 5

-0.5

Question 6

the rxn in ehich one products acts as catalyst is called

Answer 6

autocatalytic

Question 7

a typical example of an exothermic reversible rxn conducted at high pressure in industry is

Answer 7

dehydration of ethanol

Question 8

study of chemical kinetics is the easiest in case of

Answer 8

irreversible

Question 9

in autocatalytic rxn,

Answer 9

one of the products act as catalyst

Question 10

semibatch reqctor is preferred when,

Answer 10

all abc

Question 11

exposure of a photographic plate to produce a latent inage is example of

Answer 11

both b and c

very fast
photochemical

Question 12

for identical flow rate, feed composition and for elementary first order rxn, ‘N’ equal sized mixed reactors in series with a total volume V, this is true when the value of N is

Answer 12

infinity

Question 13

helium-mercury method is used for the measurement of the ___ of the catalyst

Answer 13

both b and c

porosity
pore volume

Question 14

what is the order of rxn whose rate is determined by the variation of one conc term only

Answer 14

first

Question 15

wrong statement (order and molecularity)

Answer 15

order and molecularity of a complex rxn may not be the same

Question 16

rate at which a chemical substance reacts is proportional to its

Answer 16

active mass

Question 17

the exit age distribution of a fluid leaving a vessel is used to study the extent of non-ideal flow in the vessel, value is

Answer 17

1

Question 18

plug flow reqctor is characterized by

Answer 18

presence of lateral mixing

Question 19

three plug flow reactor of 4,5,6 m3 volume. if the total feedrate is 300 tons/hr, then for the same conversion in each branch, the feed rate through branch II should be be

Answer 19

100 tons/hr

Question 20

for a tubular reactor with space time and residence time, the following statements hold good

Answer 20

space time = 0, for an isothermic tubular reactor in which the density of the process fluid is constant

Question 21

rate of an autocatalytic chemical rxn is a function of

Answer 21

all abc

temp, pressure, composition

Question 22

which of the following curves shows the effect of temperature on the extent of gas-solid adsorption at a given pressure

Answer 22

adsorption isobar

Question 23

for an ideal mixed flow reactor (CSTR), the exit age distributiib (Et) is given by

Answer 23

none of the above

Question 24

fluid flow in a real packed bed can be approximated as ___ model

Answer 24

dispersion

Question 25

for series rxn, the relative yield

Answer 25

both a and c

Question 26

the E curve for a non-ideal reactor defines the fraction of fluid having age between t and dt

Answer 26

at the outlet

Question 27

to maximize the formation of R in the simultaneous rxn,

Answer 27

low CA, high CB

Question 28

a rxn is catalyzed by an acid is also catalysed by any substance, which has a tendency to

Answer 28

lose a proton

Question 29

a stirred tank reactor compared to tubular flow reactor provides

Answer 29

all abc

Question 30

a chemical rxn A ->3B, fractional conversion is

Answer 30

1

Question 31

a catalysts inhibitor

Answer 31

all abc

Question 32

in chamber process of sulphuric acid manufacture in industry, the gas phase oxidation of SO2 to SO3 is accomplished by ___ rxn

Answer 32

catakytic homogeneous

Question 33

if the rate of chemical rxn becomes slower at a given temperature, then the

Answer 33

free energy of activatiin is higher

Question 34

the conversion XA and resident time data are collected for zero order liquid phase rxn in a stirred tank reactor, which of the following will be straight line?

Answer 34

XA vs T

Question 35

the rate of rxn X -> Y, quadruple when the conc of X is doubled. the rate of expression for the rxn is r=K Cx^n, the value of n will be

Answer 35

2

Question 36

the value of ateric factor P ranges from

Answer 36

1.0 to 10^-8

Question 37

for a zero order rxn, the concentration of product increases with the

Answer 37

increase of rxn time

Question 38

womrong statement (a batch reactor)

Answer 38

a batch reactor cannot be used to study kinetics of catalytic rxn

Question 39

effectiveness factor of a catalyst pellet is a measure of ___ resistance

Answer 39

pore diffusion

Question 40

the rate expression for a heterogeneous catalytic rxn is given by -rA = K.KA PA (1+ KA.PA + KRPR), where EA is equal to

Answer 40

E + (dHA - dHR)

Question 41

given (rxn) the KO for the rxn CO + H2O = CO2 + H2 is

Answer 41

10^0.67

Question 42

differential method for analysing the kinetic data is used

Answer 42

for testing complicated mechanisms

Question 43

in case kf th irreversible unimolecular type, first order rxn, the fractional conversion at any time for constant volume system as compared to variable volume system is

Answer 43

same

Question 44

fhe rxn in which the rate eqn correspond to stoich eqn is called

Answer 44

elementary

Question 45

the rxn A->B is conducted in an isothermal batch reactor. if the conversion of A increases linearly with holding time, then order of rxn is

Answer 45

0

Question 46

a first order gasous phase rxn is catalysed by a non-porous solid. the effective rate constant is

Answer 46

1/keff = 1/k + 1/kg

Question 47

arrhenius eqn represents graphically the variation between the ___ and temperature

Answer 47

rate constant

Question 48

catalytic rxn involved in the thermal cracking of gas oil

Answer 48

homogeneous

Question 49

variables affecting the rate of homogeneous rxn are

Answer 49

pressure, temp, compositions

Question 50

a chemicla rxn occurs when the energy if the reacting molecules is ___ the activation energy of the rxn

Answer 50

equal to or more than