Q.1
The rate constant of a chemical reaction increases by 100 times when the temperature is increased from 400 °K to 500 °K. Assuming transition state theory is valid, the value of E/R is
Q.2
Find a mechanism that is consistent with the rate equation and reaction given below: 2A + B → A₂B, ( - rA) = k.CA.CB
Q.3
Threshold energy in a reaction is equal to the
Q.4
In case of calcination of limestone, CaCO₃ CaO + CO₂, the addition of more of CaO will result in __________ in the concentration of CO₂.
Q.5
Rate constant for a first order reaction does not depend upon reaction time, extent of reaction and the initial concentration of reactants ; but it is a function of reaction temperature. In a chemical reaction, the time required to reduce the concentration of reactant from 100 gm moles/litre to 50 gm moles/litre is same as that required to reduce it from 2 gm moles/litre to 1 gm mole/litre in the same volume. Then the order of this reaction is
Q.6
For the reaction, A + B → 2B + C,
Q.7
The rate at which a chemical substance reacts is proportional to its
Q.8
The rate at which a chemical substance reacts is proportional to its
Q.9
Which of the following will give maximum gas conversion?
Q.10
For the same residence time, which one will give the maximum conversion?
Q.11
At a given temperature, K₁, K₂ and K3 are equilibrium constants for the following reactions 1, 2, 3 respectively.
CH₄(g) + H₂O(g) ⇋ CO(g) + 3H₂(g),
CO(g) + H₂O(g) ⇋ CO₂(g) + H₂(g)
CH₄(g) + 2H₂O(g) ⇋ CO₂(g) + 4H₂(g)
Then K₁, K₂ and K3 are related as:
Q.12
The catalytic activity of enzymes is due to their capacity to lower the __________ energy.
Q.13
According to the 'law of mass action', the rate of reaction is directly proportional to the
Q.14
What is the dispersion number for a CSTR?
Q.15
The equilibrium constant of chemical reaction __________ in the presence of catalyst.
Q.16
From among the following, choose one which is not an exothermic process.
Q.17
An irreversible first order reaction is being carried out in a CSTR and PFR of same volume. The liquid flow rates are same. The relative conversion will
Q.18
A first order reaction requires two equal sized CSTR. The conversion is
Q.19
A first order gaseous phase reaction is catalysed by a non-porous solid. The kinetic rate constant and the external mass transfer co-efficients are k and kg respectively. The effective rate constant (keff) is given by
Q.20
The half life period of a first order reaction is given by (where, K = rate constant. )
Q.21
The conversion of a reactant, undergoing a first order reaction, at a time equal to three times the half life of the reaction is
Q.22
A typical example of an exothermic reversible reaction conducted at high pressure in industry is
Q.23
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.
Q.24
The catalyst in a first order chemical reaction changes the
Q.25
A batch reactor is suitable for
Q.26
For a fluidised bed reactor, the most suitable/relevant model is a __________ model.
Q.27
For an ideal mixed flow reactor (CSTR), the exit age distribution E(t) is given by
Q.28
Mean residence time is equal to the space time, when
Q.29
If a solid-gas non-catalytic reaction occurs at very high temperature, the rate controlling step is the __________ diffusion.
Q.30
Catalyst is a substance, which __________ chemical reaction.
Q.31
A chemical reaction is of zero order, when the reaction rate is (where, CA = concentration of reactant)
Q.32
Limiting reactant in a chemical reaction decides the
Q.33
In an exothermic chemical reaction, the reactants compared to the products have
Q.34
An isothermal aqueous phase reversible reaction, P ⇋ R, is to be carried out in a mixed flow reactor. The reaction rate in k.mole/m³ .h is given by, r = 0.5CP - 0.125CR. A stream containing only P enters the
Q.35
If Thiele modulus is __________ , then the pore diffusion resistance in a catalyst may be considered as negligible.
Q.36
Which of the following chemical reactions will be favoured by low pressure ?
Q.37
If the rate of a chemical reaction becomes slower at a given temperature, then the
Q.38
A space time of 3 hours for a flow reactor means that
Q.39
Higher free energy of activation of a chemical reaction (at a given temperature) implies
Q.40
The time needed to achieve the same fractional conversion for particles of different sizes (d) when chemical reaction controls, is proportional to
Q.41
A trickle bed reactor is the one, which
Q.42
Study of chemical kinetics is the easiest in the case of __________ reactions.
Q.43
The eddy diffusivity for a liquid in plug flow must be
Q.44
The most suitable reactor for carrying out an auto-thermal reaction is a
Q.45
In an ideal tubular-flow reactor
Q.46
A reactor is generally termed as an autoclave, when it is a
Q.47

The minimum energy required to allow a chemical reaction to proceed is termed as the 'threshold energy '. Chemical reaction with low activation energy are

  • always irreversible.
  • insensitive to temperature changes.
  • mostly irreversible.
  • highly temperature sensitive.
Q.48

For the same residence time, which one will give the maximum conversion ?

  • Single stirred tank (v = 5 litres).
  • Two stirred tank (each of 2.5 litres) in series.
  • Stirred tank followed by tubular flow reactor (each of 2.5 litres).
  • Single tubular flow reactor (v = 5 litres).
Q.49

The synthesis of proteins and metabolism in biological objects occur in the presence of biocatalyst called

  • a ferment or an enzyme
  • haemoglobin
  • fungi
  • none of these
Q.50

If Thiele modulus is __________ , then the pore diffusion resistance in a catalyst may be considered as negligible.

  • 0
  • ∞
  • < 0.5
  • > 0.5
0 h : 0 m : 1 s