Q.1

'Unreacted core model' represents the reaction involving

  • combustion of coal particles.
  • roasting of sulphide ores.
  • manufacture of carbon disulphide from elements.
  • none of these.
Q.2

In chamber process of sulphuric acid manufacture in industry, the gas phase oxidation of SO2 to SO3 is accomplished by a __________ reaction.

  • non-catalytic homogeneous
  • non-catalytic heterogeneous
  • catalytic homogenous
  • catalytic heterogeneous
Q.3

For the irreversible elementary reactions in parallel viz , the rate of disappearance of 'X' is equal to

  • CA(K1+K2)
  • CA(K1 + K2)/2
  • CA . K1/2
  • CA . K2/2
Q.4

For a reaction of the type, , the rate of reaction (- rx) is given by

  • (K1+K1)CX
  • (K1+K2+K3)CX
  • K1CV - K2CX
  • (K1-K2)CX
Q.5

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

  • less than
  • equal to
  • more than
  • equal to or more than
Q.6

If the rate of a chemical reaction becomes slower at a given temperature, then the

  • initial concentration of the reactants remains constant.
  • free energy of activation is lower.
  • entropy changes.
  • free energy of activation is higher.
Q.7

B.E.T. method can be used to determine the __________ of a porous catalyst.

  • solid density
  • pore volume
  • surface area
  • all (a), (b) and (c)
Q.8

The conversion XA and residence time data are collected for zero order liquid phase reaction in a stirred tank reactor. Which of the following will be a straight line ?

  • XA Vs . τ
  • XA Vs ln τ
  • XA/(1 - XA)Vs τ
  • XA(1 - XA)Vs τ
Q.9

Exposure of a photographic plate to produce a latent image is an example of __________ reaction.

  • very slow
  • very fast
  • photochemical
  • both (b) and (c)
Q.10

For a series of reactions having k1 << k2, the reaction system can be approximated as

Q.11

Given,
3H2 + CO = CH4 + H2O, KP = 101.84 and,
4H2 + CO2 = CH4 + 2H2O, KP = 101.17
the KP for the reaction CO + H2O = CO2 + H2 is

  • 103.01
  • 10-0.67
  • 10-3.01
  • l00.67
Q.12

Space velocity

  • describes the extensive operating characteristics of a tubular flow reactor.
  • is the maximum feed rate pre unit volume of reactor for a given conversion.
  • is a measure of the ease of the reaction.
  • all (a), (b) and (c)
Q.13

For identical flow rate, feed composition and for elementary first order reactions, 'N' equal sized mixed reactors in series with a total volume 'V' gives the same conversion as a single plug flow reactor of volume 'V' for constant density systems. This is true, when the value of 'N' is

  • 1
  • >1
  • ∞
  • ≥1
Q.14

Helium-mercury method is used for the measurement of the __________ of the catalyst.

  • surface area
  • porosity
  • pore volume
  • both (b) & (c).
Q.15

What is the order of a chemical reaction whose rate is deter-mined by the variation of one concentration term only ?

  • zero
  • first
  • second
  • third
Q.16

The rate of the reaction, X Y, quadruples when the concentration of 'X' is doubled. The rate expression for the reaction is, r = K Cxn, the value of 'n' in this case will be

  • 0
  • 1
  • 2
  • 3
Q.17

In case of the irreversible unimolecular type, first order reaction, the fractional conversion at any time for constant volume system as compared to variable volume system is

  • more
  • less
  • same
  • either (a) or (b), depends on other factors
Q.18

The reaction in which the rate equation corresponds to a stoichiometric equation, is called a/an __________ reaction.

  • elementary
  • non-elementary
  • parallel
  • autokinetic
Q.19

Photochemical reaction rate does not depend significantly on temperature, because

  • it is a reversible reaction.
  • it is an exothermic reaction.
  • the energy of reacting molecules exceeds the activation energy by absorption of light.
  • none of these.
Q.20

A reaction which is catalysed by a base is catalysed by all substances which have a tendency to

  • lose a proton
  • gain a proton
  • gain an electron
  • none of these
Q.21

A reaction which is catalysed by a base is catalysed by all substances which have a tendency to

  • lose a proton
  • gain a proton
  • gain an electron
  • none of these
Q.22

Pick out the wrong statement.

  • Visible radiation provides the necessary activation energy in photochemical reactions.
  • The order and molecularity of a complex reaction may not be the same.
  • For a second order reaction, the slope of the graph/plot between rate and (concentration) is equal to the rate constant (k).
  • Molecularity of the reaction is always a whole number greater than zero.
Q.23

Which of the following resistances is not involved in a gas phase catalytic (gas-solid) reaction ?

  • Ash resistance.
  • Gas film and pore surface diffusion resistances for reactants.
  • Surface phenomenon resistance.
  • Gas film and pore surface diffusion resistances for products.
Q.24

Pick out the wrong statement.

  • Catalytic activity of enzyme catalysed reactions which is affected by temperature, pH value & chemical agents, is maximum at a temperature of about 45°C.
  • Most of the enzyme catalysed reactions involve at least two substrates.
  • Enzymes help in increasing the activation energy of the reaction.
  • Equilibrium concentrations in enzyme catalysed reactions can be calculated by using the thermodynamic properties of substrates & products.
Q.25

The optimum performance for reactors operating in parallel is obtained when the feed stream is distributed in such a way, that the

  • space time for each parallel line is same.
  • space time for parallel lines is different.
  • larger reactors have more space time compared to smaller ones.
  • none of these.
Q.26

According to the 'law of mass action', the rate of reaction is directly proportional to the

  • equilibrium constant.
  • volume of the reaction vessel.
  • nature of the reactants.
  • molar concentration of the reactants.
Q.27

Pick out the wrong statement.

  • Catalytic activity of enzyme catalysed reactions which is affected by temperature, pH value & chemical agents, is maximum at a temperature of about 45°C.
  • Most of the enzyme catalysed reactions involve at least two substrates.
  • Enzymes help in increasing the activation energy of the reaction.
  • Equilibrium concentrations in enzyme catalysed reactions can be calculated by using the thermodynamic properties of substrates & products.
Q.28

For a homogeneous reaction of nth order, the dimension of the rate constant is given by

  • l/(time)n
  • (concentration)1 - n/(time)
  • (concentration)n - 1/(time)
  • none of these
Q.29

If the time required to change the concentration of reactant to half its original value is independent of the initial concentration, the order of reaction is

  • zero
  • one
  • two
  • three
Q.30

There is no correspondence between stoichiometry and the rate equation in case of a/an __________ reaction.

  • elementary
  • multiple
  • autocatalytic
  • non-elementary
Q.31

A catalyst is said to be a negative catalyst, ifit

  • retards the rate of reaction.
  • reduces the value of equilibrium constant.
  • does not initiate the reaction.
  • all (a), (b) and (c).
Q.32

In a chemical reaction, __________ are conserved.

  • ions
  • masses
  • atoms
  • both(b) & (c)
Q.33

The reaction A B is conducted in an isothermal batch reactor. If the conversion of A increases linearly with holding time, then the order of the reaction is

  • 0
  • 1
  • 1.5
  • 2
Q.34

In a chemical reaction, __________ are conserved.

  • ions
  • masses
  • atoms
  • both(b) & (c)
Q.35

Which of the following is used for calcination of limestone and dolomite in industrial practice ?

  • Fluidised bed reactor
  • Moving bed reactor
  • Fixed bed reactor
  • None of these
Q.36

For the non catalytic reaction of particles with surrounding fluid, the same needed to achive the same fractional conversion for particles of different unchanging sizes is proportional to the particle diameter, when the __________ is the controlling resistance.

  • film diffusion
  • diffusion through ash layer
  • chemical reaction
  • either (a), (b) or (c)
Q.37

For an ideal gas mixture undergoing a reversible gaseous phase chemical reaction, the equilibrium constant

  • is independent of pressure.
  • increases with pressure.
  • decreases with pressure.
  • increases /decreases with pressure depending on the stoichiometric co-efficients of the reaction.
Q.38

The fractional volume change between no conversion and complete conversion, for the isothermal gas phase reaction, 2A R, is

  • 0.5
  • -0.5
  • 1
  • 1.5
Q.39

A photochemical reaction is

  • accompanied with emission of light.
  • catalysed by light.
  • initiated by light.
  • all (a), (b) & (c).
Q.40

A photochemical reaction is

  • accompanied with emission of light.
  • catalysed by light.
  • initiated by light.
  • all (a), (b) & (c).
Q.41

Which of the following is used for calcination of limestone and dolomite in industrial practice ?

  • Fluidised bed reactor
  • Moving bed reactor
  • Fixed bed reactor
  • None of these
Q.42

Pure ethanol vapor is fed to a reactor packed with alumina catalyst, at the rate ofkmole / hr. The reactor products comprise: ethylene :kmole / hr, water vapour: 97.5 k mole / hr and diethyl ether :2.5 kmole/hr. The reactions occuring can be represented by:
C2H5OH C2H4 + H2O
2C2H5OH C2H5 - O - C2H5 + H2O
The percent conversion of ethanol in the reactor is

  • 100
  • 97.5
  • 95
  • 2.5
Q.43

Pure ethanol vapor is fed to a reactor packed with alumina catalyst, at the rate ofkmole / hr. The reactor products comprise: ethylene :kmole / hr, water vapour: 97.5 k mole / hr and diethyl ether :2.5 kmole/hr. The reactions occuring can be represented by:
C2H5OH C2H4 + H2O
2C2H5OH C2H5 - O - C2H5 + H2O
The percent conversion of ethanol in the reactor is

  • 100
  • 97.5
  • 95
  • 2.5
Q.44

A photochemical reaction is

  • accompanied with emission of light.
  • catalysed by light.
  • initiated by light.
  • all (a), (b) & (c).
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