Q.1

A trickle bed reactor is the one, which

  • has altogether three streams either entering or leaving.
  • processes three reactants at different flow rates.
  • processes three reactants with same flow rate.
  • employs all the three phases (i.e.. .solid, liquid and gas).
Q.2

A chemical reaction occurs, when the energy of the reacting molecules is __________ the activation energy of reaction.

  • less than
  • equal to
  • more than
  • equal to or more than
Q.3

Holding time for flow reactors is __________ the space time, for constant fluid density

  • double
  • triple
  • equal to
  • none of these.
Q.4

Pick out the wrong statement.

  • In a multistep reaction, the slowest step is the rate determining step.
  • In general, the rate of a reaction becomes triple for every 10°C rise in temperature.
  • Slow chemical reactions have generally high values of activation energy.
  • Molecularity of a reaction can not be zero but the order of a reaction can be zero.
Q.5

For a first order isothermal chemical reaction in a porous catalyst, the effectiveness factor is 0.The effectiveness factor will increase if the

  • catalyst size is reduced or the catalyst diffusivity is reduced.
  • catalyst size is reduced or the catalyst diffusivity is increased.
  • catalyst size is increased or the catalyst diffusivity is reduced.
  • catalyst size is increased or the catalyst diffusivity is increased.
Q.6

For a first order chemical reaction, the rate constant

  • changes on changing the concentration units.
  • is not a function of the unit of time.
  • has unit of time-1.
  • none ofthese.
Q.7

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

  • tank in series
  • bubbling bed
  • plug flow
  • none of these
Q.8

Chemical kinetics can predict the __________ of a chemical reaction.

  • rate
  • feasibility
  • both (a) & (b)
  • neither (a) nor (b)
Q.9

If pore diffusion is the controlling step in a solid catalysed reaction, the catalyst

  • porosity is very important.
  • porosity is of less importance.
  • internal surface area is utilised efficiently.
  • none of these.
Q.10

The importance of diffusion in a catalyst are increased by

  • large catalyst particle size.
  • an active surface of the catalyst.
  • small pore diameter.
  • all (a), (b) and (c).
Q.11

If pore diffusion is the controlling step in a solid catalysed reaction, the catalyst

  • porosity is very important.
  • porosity is of less importance.
  • internal surface area is utilised efficiently.
  • none of these.
Q.12

Which of the following factors control the deactivation of a porous catalyst pellet ?

  • Decay reactions.
  • Pore diffusion.
  • Form of surface attack by poison.
  • All (a), (b) and (c).
Q.13

If the time required for half change is inversely proportional to the square of initial concentration and the velocity depends on the units in which the concentration term is expressed, then the order of reaction is

  • 1
  • 2
  • 3
  • 0
Q.14

In a reversible reaction, a catalyst increases the rate of forward reaction

  • only.
  • to a greater extent than that of the backward reaction.
  • and decreases that of the backward reaction.
  • and the backward reaction equally.
Q.15

What is the order of a chemical reaction in which doubling the initial concentration of the reactants doubles the half life time of the reaction ?

  • 0
  • 1
  • 2
  • 3
Q.16

Sum of the powers of the concentration terms in the rate equation is called the __________ of the reaction.

  • order
  • overall order
  • molecularity
  • none of these
Q.17

Following isothermal kinetic data are obtained in a basket type of mixed flow reactor for a porous catalyst. Determine the role of pore diffusion and external mass transfer processes.

  • Strong pore diffusion control and mass transfer not controlling.
  • Both pore diffusion and mass transfer not controlling.
  • Both pore diffusion and mass transfer controlling.
  • Mass transfer controlling.
Q.18

Cold shot cooling is only practical when the feed temperature is __________ than the reaction temperature.

  • higher
  • much higher
  • lower
  • much lower
Q.19

In a first order reaction, the time required to reduce the concentration of reactant from 1 mole/litre to 0.5 mole/litre will be __________ that required to reduce it frommoles/litre to 5 moles/litre in the same volume.

  • more than
  • less than
  • same as
  • data insufficient; can't be predicted.
Q.20

The conversion of a reactant, undergoing a first order reaction, at a time equal to three times the half life of the reaction is

  • 0.875
  • 0.5
  • 0.425
  • data insufficient to calculate
Q.21

A back mix reactor is

  • suitable for gas phase reactions.
  • ideal at very low conversion.
  • same as plug flow reactor (PFR).
  • same as ideal stirred tank reactor.
Q.22

The rate constant of a reaction is a function of the

  • time of reaction.
  • temperature of the system.
  • extent of reaction.
  • initial concentration of the reactants.
Q.23

Transition state theory gives the rate constant as

  • K α e-E/RT
  • K α eE/RT
  • K α T . e-E/RT
  • K α T . e-E/RT
Q.24

In a continuous flow stirred tank reactor, the composition of the exit stream

  • is same as that in the reactor.
  • is different than that in the reactor.
  • depends upon the flow rate of inlet stream.
  • none of these.
Q.25

Maximum equilibrium conversion for endothermic reaction is obtained at the __________ temperature.

  • highest possible
  • lowest possible
  • intermediate
  • room
Q.26

The excess energy of the reactants required to dissociate into products is known as the __________ energy.

  • thermal
  • activation
  • threshold
  • binding
Q.27

The preferred reacting system for oxidation of o-xylene to phthalic anhydride is

  • jacketted liquid phase CSTR.
  • jacketted steam heated multitubular reactor.
  • multitubular reactor with cooling.
  • multistage multitubular reactor with interstage cooling.
Q.28

Photo-chemical reactions occur in presence of

  • sunlight.
  • darkness,
  • solid catalysts.
  • monochromatic radiation only.
Q.29

Which one is the rate controlling step in a solid-gas non-catalytic reaction occurring at very high temperature?

  • Pore diffusion
  • Film diffusion
  • Ash layer diffusion
  • Chemical reaction
Q.30

Mean residence time is equal to the space time, when

  • the feed rate is measured at temperature and pressure in the reactor.
  • the temperature, pressure and the density of reaction mixture remains constant throughout the reactor.
  • there is no change in number of moles in gaseous reaction.
  • all (a), (b) and (c).
Q.31

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

  • CSTR of volume V
  • PFR of volume V
  • CSTR of volume V/X
  • PFR of volume V/X
Q.32

A batch reactor suffers from following disadvantage.

  • Poor product quality control.
  • High labour and handling cost.
  • High shutdown time requirement for emptying, cleaning and refilling.
  • All (a), (b)and(c).
Q.33

Pick out the wrong statement.

  • Use of different catalysts in a reversible catalytic chemical reaction does not change the equilibrium composition.
  • Alumina is added as a promoter to iron catalyst in ammonia synthesis reaction.
  • Activation energy for a reaction is obtained from the intercept of the Ar-rhenious plot.
  • Presence of inerts affects the equilibrium conversion of reactants in a chemical reaction.
Q.34

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.

  • decrease
  • increase
  • no change
  • either (a) or (b), depends on the type of reaction
Q.35

The energy balance equation over a tubular reactor under transient conditions is

  • an ordinary non-linear differential equation.
  • an algebric differential equation.
  • a linear partial differential equation.
  • a non-linear partial differential equation.
Q.36

When an exothermic reversible reaction is conducted adiabatically, the rate of reaction

  • continuously increases.
  • continuously decreases.
  • passes through a maximum.
  • passes through a minimum.
Q.37

For a first order chemical reaction in a porous catalyst, the Thiele modulus isThe effectiveness factor is approximately equal to

  • 1
  • 0.5
  • 0.1
  • 0
Q.38

Inversion of cane sugar is an example of

  • unimolecular reaction with first order.
  • bimolecular reaction with second order.
  • bimolecular reaction with first order.
  • unimolecular reaction with second order.
Q.39

In a/an __________ vessel, the fluid enters and leaves following plug flow.

  • open
  • closed
  • open-closed
  • close-opened
Q.40

Shift conversion reaction

  • converts N2 and H2 into NH3.
  • converts CO to CO2 with steam.
  • is non-catalytic.
  • is highly exothermic.
Q.41

Pick out the wrong statement.

  • Use of different catalysts in a reversible catalytic chemical reaction does not change the equilibrium composition.
  • Alumina is added as a promoter to iron catalyst in ammonia synthesis reaction.
  • Activation energy for a reaction is obtained from the intercept of the Ar-rhenious plot.
  • Presence of inerts affects the equilibrium conversion of reactants in a chemical reaction.
Q.42

The energy balance equation over a tubular reactor under transient conditions is

  • an ordinary non-linear differential equation.
  • an algebric differential equation.
  • a linear partial differential equation.
  • a non-linear partial differential equation.
Q.43

'n' number of plug flow reactors (P.F.R) in series with a total volume 'V' gives the same conversion as one P.F.R. of volume

  • V/n
  • V
  • V.n
  • 1/V
Q.44

Knudsen diffusion is directly proportional to

  • T
  • T
  • 1/T
  • T2
Q.45

Inversion of cane sugar is an example of

  • unimolecular reaction with first order.
  • bimolecular reaction with second order.
  • bimolecular reaction with first order.
  • unimolecular reaction with second order.
Q.46

The equilibrium constant K of a chemical reaction depends on

  • temperature only.
  • pressure only.
  • temperature and pressure.
  • ratio of reactants.
Q.47

If 'n' is the order of reaction, then unit of rate constant is

  • 1/(time)(concentration)n - 1
  • (time)-1 (concentration)n - 1
  • (time)n - 1 (concentration)
  • none of these
Q.48

What is the value of 'n' if the reaction rate of the chemical reaction A B, is proportional to CAn and it is found that the reaction rate triples, when the concentration of 'A' is increased 9 times ?

  • 1/2
  • 1/3
  • 1/9
  • 3
Q.49

Time required fordecomposition of a liquid in an isothermal batch reactor following first order kinetics is 2 minutes. The time required fordecomposition will be about __________ minutes.

  • 3
  • 4
  • 6
  • 8
Q.50

For a __________ order reaction, the units of rate constant and rate of reaction are the same.

  • zero
  • first
  • second
  • fractional
0 h : 0 m : 1 s