(4) Chemical Reactions Engineering Flashcards
(497 cards)
1
Q
Which of the following will give maximum gas conversion?
A
Semi fluidized bed reactor
2
Q
__________ explains the mechanism of catalysis.
A
Activated complex theory
3
Q
The fractional volume change of the system for the isothermal gas phase reaction, A 3B , between no conversion and complete conversion is
A
2
4
Q
A catalyst
A
5
Q
What is the order of a chemical reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/450-191-1.png , if the rate of formation of ‘C’, increases by a factor of 2.82 on doubling the concentration of ‘A’ and increases by a factor of 9 on trebling the concentration of ‘B’?
A
6
Q
For high conversion in a highly exothermic solid catalysed reaction, use a __________ bed reactor.
A
7
Q
For every 10°C rise in temperature, the rate of chemical reaction doubles. When the temperature is increased from 30 to 70°C, the rate of reaction increases __________ times.
A
8
Q
The single parameter model proposed for describing non-ideal flow is the __________ model.
A
9
Q
A first order reaction requires two equal sized CSTR. The conversion is
A
10
Q
In case of physical adsorption, the heat of adsorption is of the order of __________ kcal/kg.mole.
A
11
Q
The most unsuitable reactor for carrying out reactions in which high reactant concentration favours high yields is
A
12
Q
Pick out the wrong statement pertaining to space velocity of flow reactors.
A
13
Q
A reactor is generally termed as an autoclave, when it is a
A
14
Q
6 gm of carbon is burnt with an amount of air containing 18 gm oxygen. The product contains 16.5 gms CO2 and 2.8 gms CO besides other constituents. What is the degree of conversion on the basis of disappearance of limiting reactant ?
A
15
Q
The rate constant of a chemical reaction decreases by decreasing the
A
16
Q
Reaction rate equation for the reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/448-153-1.png . If S at is present in large excess, what is the order of this reaction?
A
17
Q
Rate of a gaseous phase reaction is given by, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/460-311-1.png . The unit of rate constant is
A
18
Q
__________ is the response curve for a step input signal from a reactor.
A
19
Q
If the catalyst pore size is small in comparison with the mean free path, collisions with the pore wall controls the process’. The diffusivity under this condition is called ‘Knudsen diffusivity’, which is affected by the
A
20
Q
Which of the following is the most suitable for very high pressure gas phase reaction ?
A
21
Q
The reaction between oxygen and organic material is a/an __________ reaction.
A
22
Q
With decrease in temperature, the equilibrium conversion of a reversible endother-mic reaction
A
23
Q
In an exothermic chemical reaction, the reactants compared to the products have
A
24
Q
For a reaction of the type, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/458-286-1.png , the rate of reaction (- rx) is given by
A
25
In a consecutive reaction system https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/446-134-1.png when E1 is much greater than E2, the yield of B increases with the
26
A reversible liquid phase endothermic reaction is to be carried out in a plug flow reactor. For minimum reactor volume, it should be operated such that the temperature along the length
27
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
28
A batch reactor is suitable for
29
For a heterogeneous catalytic reaction
30
The increase in the rate of reaction with temperature is due to
31
A catalyst loses its activity due to
32
N' plug flow reactors in series with a total volume 'V' gives the same conversion as a single plug flow reactor of volume 'V' for __________ order reactions.
33
Specific rate constant for a second order reaction
34
For the irreversible elementary reactions in parallel viz https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/455-247-1.png , the rate of disappearance of 'X' is equal to
35
For an isothermal variable volume batch reactor, the following relation is applicable for a first order irreversible reaction.
36
For a zero order chemical reaction, the
37
BET apparatus
38
Radioactive decay follows __________ order kinetics.
39
The excess energy of reactants in a chemical reaction required to dissociate into products is termed as the __________ energy.
40
For a solid catalysed chemical reaction, the effectiveness of solid catalyst depends upon the __________ adsorption.
41
Pick out the correct statement.
42
The dimensions of rate constant for reaction 3A --> B are (l/gm mole)/min. Therefore the reaction order is
43
Pick out the correct statement
44
If the time required to complete a definite fraction of reaction varies inversely as the concentration of the reactants, then the order of reaction is
45
Sulphuric acid is used as a catalyst in the
46
Fractional conversion __________ with increase in pressure for ammonia synthesis reaction i.e., N2 + 3H2 <->2NH3.
47
Pick out the wrong statement.
48
The reason why a catalyst increases the rate of reaction is that, it
49
A first order irreversible reaction, A --> B is carried out separately in a constant volume as well as in a variable volume reactor for a particular period. It signifies that __________ in the two reactors.
50
When the density of the reaction mixture is constant in a chemical reaction, the ratio of the mean residence time to space time is
51
In an ideal tubular-flow reactor
52
At a given value of E/R (ratio of activation energy and gas constant), the ratio of the rate constants at 500°K and 400°K is 2, if Arrhenious law is used. What will be this ratio, if transition state theory is used with the same value of E/R?
53
__________ is the controlling step in a highly temperature sensitive fluid-solid non-catalytic reaction.
54
An autothermal reactor is
55
The rate constant of a first order reaction depends on the
56
A reaction in which one of the products of reaction acts as a catalyst is called a/an __________ reaction.
57
The ratio of volume of mixed reactor to the volume of P.F.R. (for identical flow rate, feed composition and conversion) for zero order reaction is
58
Which of the following will favour the reverse reaction in a chemical equilibrium reaction ?
59
Conversion increases with increase in temperature in case of a an __________ reaction.
60
Effective diffusivity (DE) in a catalyst pellet is related to molecular diffusivity (DN) and Knudsen diffusivity (DK) as
61
A photochemical reaction is __________ light.
62
Pick out the wrong statement.
63
In a/an __________ reactor, there is exchange of heat with the surroundings with sizeable temperature variation.
64
Unreacted core model' represents the reaction involving
65
For a vapour phase catalytic reaction (A + B --> P) which follows the Ridel mechanism and the reaction step is rate controlling, the rate of reaction is given by (reaction rate is irreversible, product also absorbs).
66
If a solid-gas non-catalytic reaction occurs at very high temperature, the rate controlling step is the __________ diffusion.
67
The units of frequency factor in Arhenious equation
68
Which of the following is not a chemical step in a fluid solid catalytic reaction ?
69
For a series of reactions https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/473-457-1.png having k1 << k2, the reaction system can be approximated as
70
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:
71
In case of __________ reactions, the reaction rate does not decrease appreciably as the reaction proceeds.
72
For nearly isothermal operation involving large reaction time in a liquid-phase reaction, the most suitable reactor is a __________ reactor.
73
What is the Thiele modulus of the solid catalysed first order reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/448-154-1.png , if the pore diffusion offers negligible resistance to reaction ?
74
B.E.T. method can be used to determine the __________ of a porous catalyst.
75
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
76
Which of the following is an independent variable for a batch tank reactor with uniform concentration and temperature?
77
For reactions in parallel viz A -->P (desired product) and A-->Q (unwanted product), if the order of the desired reaction is higher than that of the undesired reaction, a
78
For a gaseous phase reaction, rate of reaction is equal to K. CA . CB. If the volume of the reactor is suddenly reduced to l/4th of its initial volume, then the rate of reaction compared to the original rate will be __________ times.
79
In a reversible chemical reaction having two reactants in equilibrium, if the concentration of the reactants are doubled, then the equilibrium constant will
80
The equilibrium constant of a catalytic chemical reaction __________ due to the presence of a catalyst.
81
The rate constant of a chemical reaction increases by increasing the
82
The catalytic activity of enzymes is due to their capacity to lower the __________ energy.
83
A first order reaction requires two unequal sized CSTR. Which of the following gives higher yield ?
84
Pick out the correct statement.
85
The effect of increasing pressure on the gaseous equilibrium of the reaction 2X+3Y <-->3X+2Y indicates that
86
If in the gaseous phase reaction, N2O4 <--> 2NO2, x is the part of N2O4 which dissociates, then the number of molecules at equilibrium will be
87
A batch reactor is characterised by
88
When a catalyst increases the rate of forward reaction, the value of rate constant
89
Rate determining step in a reaction consisting of a number of steps in series is the __________ step.
90
The rate of a chemical reaction is almost doubled for every 10°C rise in temperature. The rate will increase __________ times, if the temperature rises form 10 to 100°C.
91
A catalyst in a chemical reaction __________ free energy change in the reaction.
92
Signal normally used to study non-ideal flow by stimulus response technique is __________ input.
93
When all the limiting reactant is consumed in the reaction, the operational yield __________ the relative yield.
94
The half life period of a first order reaction is
95
The catalyst in a second order reversible reaction increases the rate of the forward reaction
96
Catalyst carriers
97
For the liquid phase zero order irreversible reaction A--> B, the conversion of A in a CSTR is found to be 0.3 at a space velocity of 0.1min-1 . What will be the conversion for a PFR with a space velocity of 0.2 min-1? Assume that all the other operating conditions are the same for CSTR and PFR.
98
A high space velocity means that a given
99
In flow reactors, the performance equations interrelate the rate of reaction to the
100
Space velocity
101
The rate of the chemical reaction A -->B doubles as the concentration of A i.e.., CA is doubled. If rate of reaction is proportional to CAn, then what is the value of n for this reaction ?
102
A reaction which is catalysed by a base is catalysed by all substances which have a tendency to
103
For a homogeneous reaction of nth order, the dimension of the rate constant is given by
104
The fractional volume change between no conversion and complete conversion, for the isothermal gas phase reaction, 2A-->R, is
105
The reaction in which one of the products of reaction acts as a catalyst is called a/an __________ reaction.
106
A typical example of an exothermic reversible reaction conducted at high pressure in industry is
107
Study of chemical kinetics is the easiest in the case of __________ reactions.
108
In autocatalytic reactions,
109
Semibatch reactor is preferred, when a/an
110
Exposure of a photographic plate to produce a latent image is an example of __________ reaction.
111
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
112
Helium-mercury method is used for the measurement of the __________ of the catalyst.
113
What is the order of a chemical reaction whose rate is deter-mined by the variation of one concentration term only?
114
Pick out the wrong statement.
115
The rate at which a chemical substance reacts is proportional to its
116
The exit age distribution of a fluid leaving a vessel (denoted by E) is used to study the extent of non-ideal flow in the vessel. The value of https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/467-387-1.png is
117
A plug-flow reactor is characterised by
118
Three plug flow reactors (PFR's) of 4, 5 & 6 m3 volumes are arranged in two branches as shown below in the figure. https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/468-389-1.png If the total feed rate is 300 tons/hr, then for the same conversion in each branch, the feed rate through branch II should be __________ tons/hr.
119
For a tubular reactor with space time 'τ' and residence time 'θ', the following statement holds good.
120
Rate of an autocatalytic chemical reaction is a function of
121
Which of the following curves shows the effect of temperature on the extent of gas-solid adsorption at a given pressure?
122
For an ideal mixed flow reactor (CSTR), the exit age distribution E(t) is given by
123
Fluid flow in a real packed bed can be approximated as __________ model.
124
For series reaction, the relative yield
125
The 'E' curve for a non-ideal reactor defines the fraction of fluid having age between t and t + dt
126
To maximise the formation of R in the simultaneous reaction
A + B --> R , rR = 2CA^0.5.CB^2
A + B --> S , rS = 1.5 CA . CB
We should have
127
A reaction which is catalysed by an acid is also catalysed by any substance, which has a tendency to
128
A stirred tank reactor compared to tubular-flow reactor provides
129
A chemical reaction, A -->3B, is conducted in a constant pressure vessel. Starting with pure A, the volume of the reaction mixture increases 3 times in 6 minutes. The fractional conversion is
130
A catalyst inhibitor
131
In chamber process of sulphuric acid manufacture in industry, the gas phase oxidation of SO2 to SO3 is accomplished by a __________ reaction.
132
If the rate of a chemical reaction becomes slower at a given temperature, then the
133
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 ?
134
The rate of the reaction, X--> Y, quadruples when the concentration of 'X' is doubled. The rate expression for the reaction is, r = K Cx^n, the value of 'n' in this case will be
135
The value of steric factor 'P' in the equation k = PZe^E/RT usually ranges from
136
For a zero order reaction, the concentration of product increases with the
137
Pick out the wrong statement.
138
Effectiveness factor of a catalyst pellet is a measure of the __________ resistance.
139
The rate expression for a heterogenous catalytic reaction is given by, - rA = K.KA PA(1 + KA.PA + KR.PR), where K is surface reaction rate constant and KA and KR are absorption equilibrium constants of A and R respectively. If KR PR >> (1 + KA PA), the apparent activation energy EA is equal to (given E is the activation energy for the reaction and ΔHR and ΔHA are the activation energies of adsorption of R and A)
140
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
141
Differential method for analysing the kinetic data is used
142
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
143
The reaction in which the rate equation corresponds to a stoichiometric equation, is called a/an __________ reaction.
144
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
145
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
146
Arrhenious equation represents graphically the variation between the __________ and temperature.
147
__________ catalytic reaction is involved in the thermal cracking of gas oil.
148
Variables affecting the rate of homogeneous reactions are
149
A chemical reaction occurs when the energy of the reacting molecules is __________ the activation energy of the reaction.
150
Which of the following resistances is not involved in a gas phase catalytic (gas-solid) reaction?
151
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
152
A batch adiabatic reactor at an initial temperature of 373°K is being used for the reaction, A-->B. Assume the heat of reaction is - 1kJ/mole at 373°K and heat capacity of both A and B to be constant and equal to 50J/mole.K. The temperature rise after a conversion of 0.5 will be
153
If CA is the quantity of reactants initially present, the quantity left after 'n' half periods will be equal to
154
A photochemical reaction is
155
The rate controlling step for the heterogeneous irreversible catalytic reaction A(g) + B(g)--> C(g) is the surface reaction of absorbed A with absorbed B to give adsorbed C. The rate expression for this reaction can then be written as (where, KA, KB and KC are the equilibrium constants and is the rate constant of the rate controlling step.)
156
The optimum performance for reactors operating in parallel is obtained when the feed stream is distributed in such a way, that the
157
A catalyst is said to be a negative catalyst, ifit
158
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.
159
Pure ethanol vapor is fed to a reactor packed with alumina catalyst, at the rate of 100 kmole / hr. The reactor products comprise: ethylene :95 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
160
The conversion for a second order, irreversible reaction (constant volume), https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/475-469-1.png , in batch mode is given by
161
Pick out the wrong statement.
162
A backmix reactor
163
Rate of a chemical reaction is not influenced by the
164
Pick out the wrong statement:
165
The reaction A B is conducted in an adiabatic plug flow reactor (PFR). Pure A at a concentration of 2 kmol/m3 is fed to the reactor at the rate of 0.01 m3 /s and at a temperature of 500 K. If the exit conversion is 20%, then the exit temperature (in k)is (Data: Heat of reaction at 298 K = - 50000 kJ/ kmole of A reacted Heat capacities CPA = CPB = 100kJ/kmole. K (may be assumed to be independent of temperature))
166
Which of the following is not a theory of homogeneous reaction?
167
A first order homogeneous reaction of the type X Y Z (consecutive reaction) is carried out in a CSTR. Which of the following curves respectively show the variation of the concentration of X, Y and Z with time? https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/446-129-1.png
168
In a semi-batch reactor,
169
Most important characteristics of gas-liquid reactors are the
170
Which of the following is a controlling factor in very fast heterogeneous reaction?
171
Enzymes are destroyed, when the
172
For an autocatalytic reactor, the suitable reactor set up is
173
Ionic reactions occur in
174
Sometimes, batch process is preferred over continuous process, when the product
175
In a chemical reaction https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/454-240-1.png , it is observed that the
(i) rate of formation of 'P' is doubled on doubling the concentration of 'X'.
(ii) rate of formation of 'P' is quadrupled on doubling the concentration of 'Y'.
(iii) doubling the concentration of 'Z' does not affect the rate of formation of 'P'.
What is the order of the above chemical reaction?
176
The half life period of a first order reaction is given by (where, K = rate constant. )
177
Half life period of a chemical reaction is
178
In the gaseous phase ammonia formation reaction (N2 + 3H2<-->2NH3), the value of the equilibrium constant depends on the
179
Transition state theory relates the above quantities as
180
Photochemical reaction rate does not depend significantly on temperature, because
181
A CSTR is to be designed in which an exothermic liquid phase first order reaction of the type, A-->R, is taking place. The reactor is to be provided with a jacket in which coolant is flowing. Following data is given: CA0= 5 kmole/m3 ; XA = 0.5; Feed temperature = reactor temperature = 40°C. Rate constant at 40°C = 1 min-1 ; (ΔH) = - 40kJ/mole; ρ = 1000kg/m3 CP = 4 J/gm.°C ; q = 10-3 m3/min (ρ and CP are same for the reactant and product streams). The amount of heat to be removed is
182
According to the 'law of mass action', the rate of reaction is directly proportional to the
183
In a chemical reaction, __________ are conserved.
184
For an ideal gas mixture undergoing a reversible gaseous phase chemical reaction, the equilibrium constant
185
In the reversible reaction of the type, A + B <--> AB, in general
186
A batch reactor is
187
For a first order reaction carried out in a plug flow reactor, the space time is
188
For an isothermal second order aqueous phase reaction, A --> B, the ratio of the time required for 90% conversion to the time required for 45% conversion is
189
A chemical reaction is of zero order, when the reaction rate is (where, CA = concentration of reactant)
190
Second order consecutive irreversible reactions https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/473-457-1.png were carried out in a constant volume isothermal batch reactor with different initial feed compositions. Reactor temperature was same in all the cases. In experiments where the ratio of concentration of B to that of A in the initial feed was less than 0.5, the concentration of B increased first, reached a maximum and then declined with time. However, for all experiments where this concentration ratio was 0.5 or above, concentration of B decreased monotonically with time right from the beginning. What is the ratio of the two rate constants (k1/k2)?
191
Pick out the wrong statement.
192
There is no correspondence between stoichiometry and the rate equation in case of a/an __________ reaction.
193
A spherical porous catalyst particle of radius R is subjected to reactant A which reacts to form B by a zero order surface reaction A B. Film mass transfer resistance is negligible and pore diffusion of A is rate controlling. The effectiveness factor of the catalyst is reported as 7/8. Which of the following statement is true?
194
Which of the following is used for calcination of limestone and dolomite in industrial practice ?
195
An imbalanced chemical reaction equation is against the law of
196
For the chemical reaction P Q, it is found that the rate of reaction doubles as the concentration of 'P' is doubled. If the reaction rate is proportional to Cpn, then what is the value of 'n' for this chemical reaction ?
197
Which of the following is a characteristic of an ideal plug flow reactor ?
198
Velocity of a reaction depends upon the
199
Threshold energy in a reaction is equal to the
200
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 reactor. The residence time required (in hours) for 40% conversion of P is
201
Design of heterogeous catalytic reactor involves consideration of __________ steps.
202
A consecutive reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/446-133.png , is characterised by
203
What is the unit of the rate constant in a chemical reaction in which 10% of the reactant decomposes in one hour, 20% in two hours, 30% in three hours and so on ?
204
For a fluidised bed reactor, the most suitable/relevant model is a __________ model.
205
The rate at which a chemical substance reacts is proportional to its
206
In a reaction, the threshold energy is equal to (where, A = activation energy N = normal energy of reactants)
207
Thermodynamic equilibrium constant in a system is affected by
208
The most suitable reactor for carrying out an auto-thermal reaction is a
209
Which of the following chemical reactions will be favoured by low pressure ?
210
A catalyst in a chemical reaction
211
Slurry reactors are characterised by the
212
Limiting reactant in a chemical reaction decides the
213
Consider the 'n' th order irreversible liquid phase reaction A --> B. Which one of the following plots involving half life of the reaction (t1/2) and the initial reactant concentration (CA0) gives a straight line plot ?
214
The rate of forward reaction, at chemical equilibrium is____the rate of backward reaction.
215
Pick the WRONG design guideline for a reactor in which the reactions, A -->R (desired) and A --> S (undesired) are to take place. The ratio of the reaction rates is https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/478-493-1.png .
216
With increase in temperature, the equilibrium __________ rises in case of endothermic reaction.
217
In case of a consecutive unimolecular type first order reaction https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/449-170-1.png , the concentration of component __________ increases continuously with time.
218
Enzymes (a protein) are catalysts found in organisms. Its efficiency of catalysing a reaction is due to its capacity to lower the activation energy of the reaction. The enzyme ptyalin used for food digestion is present in
219
Considering the endotheomic dissociation of CaCO3 in a closed vessel (CaCO3 <-->CaO + CO2), the pressure of CO2 increases, if
220
The exit age distribution of fluid leaving a vessel is used to know the
221
From Arhenius law, a plot of loge K versus 1/T gives a straight line with a slope of (-E/R). The unit of E/R is
222
In the converter of the contact process for the manufacture of H2SO4 the equilibrium conversion of SO2 __________ (A) __________ with increase in temperature and __________ (B) __________ with increase in the mole ratio of SO2 to air.
223
For the irreversible elementary first order reaction in parallel viz. https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/455-248-1.png , a plot of Cy Vs. Cz will give a straight line having a slope of
224
The time needed to achieve the same fractional conversion for particles of different sizes (d) when chemical reaction controls, is proportional to
225
A balanced chemical reaction equation conforms to the law of
226
An exothermic reaction takes place in an adiabatic reactor. The product temperature __________ reactor feed temperature.
227
Reverse reaction in a chemical equilibrium is favoured by the
228
The equilibrium constant for the reversible reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/449-174-1.png , is affected by the
229
Sum of the powers of the concentration terms in the rate equation is called the __________ of the reaction.
230
During manufacture of H2SO4, the oxidation of SO2 to SO3 by oxygen is an en-dothermic reaction. The yield of SO3 will be maximised, if the
231
The role of a catalyst in a chemical reaction is to change the
232
The vessel dispersion number (D/μL) for plug flow is
233
Molecularity of a reaction
234
BET apparatus is used to determine the
235
Carrier in a catalyst increases its
236
When the reaction is dominated by in-traparticle diffusion, the apparent order of reaction (nD) as measured is related to the true order (n) as
237
When the reaction occurs in the diffusion controlled region, the apparent activation energy as measured is only __________ the true value.
238
An isothermal irreversible reaction is being carried out in an ideal tubular flow reactor. The conversion in this case will __________ with decrease in space time.
239
An elementary liquid phase decomposition reaction https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/476-479-1.png is to be carried out in a CSTR. The design equation is
240
Kinetics of a solid catalysed reaction can best be studied in a __________ reactor.
241
According to Arhenious equation of temperature dependency of rate constant for an elementary reaction
242
The reactions of high molecularity are rare, because
243
Which of the following is the most suitable for isothermal operation ?
244
For a first order chemical reaction, the rate constant
245
Which of the following is an autocatalytic reaction ?
246
The performance of a cascade of CSTR's can be improved by adding
247
A multiple reaction may be classified as a __________ reaction.
248
Holding time for flow reactors is __________ the space time, for constant fluid density
249
Pick out the wrong statement.
250
The order of the reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/448-162-1.png , is
251
Arhenious equation shows the variation of __________ with temperature.
252
When a catalyst increases the rate of chemical reaction, the rate constant
253
In which of the following reactions, the equilibrium will shift to the right, if the total pressure is increased?
254
The catalyst in a first order chemical reaction changes the
255
Oil is hydrogenated using nickel catalyst in a __________ reactor.
256
The performance equations for constant density systems are identical for
257
Reaction rate of a first order reaction, which is half completed in 23 minutes will be
258
Which of the following is the optimum operating condition for an exothermic reversible reaction taking place in a plug-flow reactor ?
259
The half life period 't' of a zero order reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/449-168-1.png , is equal to
260
The point selectivity of the product 'Y' in the reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/458-295-1.png is equal to
261
In case of calcination of limestone, CaCO3 CaO + CO2, the addition of more of CaO will result in __________ in the concentration of CO2.
262
The rate of a homogeneous reaction is a function of
263
In the fluid catalytic cracker (FCC), the cracking reaction is __________ (A) and the regeneration is___(B) __________
264
Pick out the correct statement.
265
Promoter is added to the catalyst to improve its
266
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
267
When a high liquid hold up is required in a reactor for gas liquid reaction, use __________ coloumn.
268
In an exothermic reaction, the energy of the reacting substances as compared to that of products is
269
For a tubular flow reactor with uniform concentration and temperature, the independent variable is
270
Pick out the wrong statement.
271
The first order gas phase reaction https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/475-470-1.png is conducted isothermally in batch mode. The rate of change of conversion with time is given by
272
The extent of a reaction is
273
Higher free energy of activation of a chemical reaction (at a given temperature) implies
274
Calcination reaction of limestone (CaCO3 --> CaO + CO2) goes to completion in the rotary kiln, because
275
The reactions with low activation energy are
276
Molecularity of an elementary reaction, P + Q --> R + S is
277
Which of the following is not endothermic in nature ?
278
The rate of an autocatalytic reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/467-388-1.png , is given by -rA = k . CA . CB. In this case, the
279
The space time is equivalent to the holding time in a steady state mixed reactor for
280
The dispersion number of perfect mixed flow is
281
For the reaction https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/454-239-1.png , the rate of formation of Z is 0.2 gm mole/litre.hr. what is the rate of disappearance of X in gm mole/litre. hr ?
282
An irreversible aqueous phase reaction, A + B --> P, is carried out in an adiabatic mixed flow reactor. A feed containing 4kmole/m3 of each A and B enters the reactor at 8m3 /hr. If the temperature of the exit stream is never to exceed 390 K, what is the maximum inlet feed temperature allowed?
Data: Heat of reaction = - 50 kJ/mole
Density of the reacting mixture = 1000kg/m3
Specific heat of reacting mixture = 2kJ/kg.K
The above data can be assumed to be independent of temperature and composition.
283
For a heterogenous catalytic reaction, A + B --> C, with equimole feed of A and B, the initial rate - rA0 is invariant with total pressure. The rate controlling step is
284
Half life period of a first order irreversible reaction A B is
285
Pick out the wrong statement.
286
Which of the following is not a dimension-less group used in catalysis ? (where, D = dispersion co-efficient, cm2 /sec.D1 = diffusion co-efficient; cm2/sec L = length of the reactor, cm t = time, sec, v = volumetric flow rate, cm3/sec . V = volume, cm3.)
287
Pick out the wrong statement
288
The energy of activation of a chemical reaction
289
Chemical kinetics can predict the __________ of a chemical reaction.
290
Which of the following fixes the volume of a batch reactor for a particular conversion and production rate?
291
Volume change for unimolecular type first order reaction https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/449-172-1.png , increases __________ with time.
292
Half life period of decomposition of a liquid 'A' by irreversible first order reaction is 12 minutes. The time required for 75% conversion of 'A' is __________ minutes.
293
Decomposition rate of a liquid 'X' which decomposes as per the reaction https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/456-270-1.png is given by
294
With increase in the space time of an irreversible isothermal reaction being carried out in a P.F. reactor, the conversion will
295
A catalyst promoter
296
In case of a P.F.R., there
297
For the non-catalytic reaction of particles with surrounding fluid, the time needed to achieve the same fractional conversion for particles of different but unchanging sizes is proportional to the square of particle diameter, when the __________ is the controlling resistance.
298
If ΔG (free energy change) for a chemical reaction is very large and negative, then the reaction is
299
In a zero order reaction, reactants concentration does not change with time and the
300
The minimum energy required to allow a chemical reaction to proceed is termed as the 'threshold energy '. Chemical reaction with low activation energy are
301
If Thiele modulus is __________ , then the pore diffusion resistance in a catalyst may be considered as negligible.
302
From collison theory, the reaction rate constant is proportional to
303
For a mixed flow reactor operating at steady state, the rate of reaction is given by
304
Catalytic action in a catalytic chemical reaction follows from the ability of catalyst to change the
305
In Langmuir treatment of adsorption,
306
Organic catalysts differ from the inorganic catalyst in the sense that the former is
307
An endothermic aqueous phase first order irreversible reaction is carried out in an adiabatic plug flow reactor. The rate of reaction
308
Pick out the wrong statement.
309
For an ideal plug flow reactor, the value of Peclet number is
310
An endothermic second order reaction is carried out in an adiabatic plug flow reactor. The rate of heat generation is
311
Equilibrium of a chemical reaction as viewed by kinetics is a __________ state.
312
The conversion in a mixed reactor/accomplishing a reaction A -->3R is 50% when gaseous reactant 'A' is introduced at the rate of 1 litre/second and the leaving flow rate is 2 litres/second. The holding time for this operation is __________ second.
313
The size of plug flow reactor (PFR) for all positive reaction orders and for any given duty, is __________ that of mixed reactor.
314
A space time of 3 hours for a flow reactor means that
315
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
316
The experimentally determined overall order of the reaction, A + B --> C + D, is two. Then the
317
In a continuous flow stirred tank reactor, the composition of the exit stream
318
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.
319
The energy balance equation over a tubular reactor under transient conditions is
320
Which of the following factors control the deactivation of a porous catalyst pellet ?
321
For the reaction, A + B -->2B + C,
322
Transition state theory gives the rate constant as
323
A liquid phase reaction is to be carried out under isothermal conditions. The reaction rate as a function of conversion has been determined experimentally and is shown in the figure given below. What choice of reactor or combination of reactors will require the minimum overall reactor volume, if a conversion of 0.9 is desired ?
324
Pick out the wrong statement.
325
In a reversible reaction, a catalyst increases the rate of forward reaction
326
Maximum equilibrium conversion for endothermic reaction is obtained at the __________ temperature.
327
When an exothermic reversible reaction is conducted adiabatically, the rate of reaction
328
For a first order chemical reaction in a porous catalyst, the Thiele modulus is 10. The effectiveness factor is approximately equal to
329
The rate equation for the reaction represented by https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/455-245-1.png , is given by - rx = K1 . Cx/(1 + K2 Cx). At high value of Cx (i.e.., K2Cx > > 1), the order of the reaction and the rate constant are respectively
330
In solid catalysed reactions the diffusional effects are more likely to affect the overall rate of reaction for
331
Helium-mercury method can be used to determine the __________ of the catalyst particle.
332
For the chemical reaction X --> Y, it is observed that, on doubling the concentration of 'X', the reaction rate quadruples. If the reaction rate is proportional to Cxn, then what is the value of 'n' ?
333
Chemical reaction rate of a component depends upon the
334
In a semi-batch reactor
335
A trickle bed reactor is the one, which
336
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 ?
337
The excess energy of the reactants required to dissociate into products is known as the __________ energy.
338
In a/an __________ vessel, the fluid enters and leaves following plug flow.
339
Shift conversion reaction
340
The importance of diffusion in a catalyst are increased by
341
A back mix reactor is
342
Which one is the rate controlling step in a solid-gas non-catalytic reaction occurring at very high temperature?
343
The rate of the heterogenous catalytic reaction A(g) + B(g) -->C(g) is given by -rA = k.KA.pA.PB/(1 + KA.PA + Kc.pc), where KA and Kc are the adsorption equilibrium constants. The rate controlling step for this reaction is
344
For a __________ order chemical reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/449-168-1.png , the half life period is independent of the initial concentration of the reactant A.
345
The ratio of moles of a reactant converted into the desired product to that converted into unwanted product is called
346
The response curve for a step input signal from a reactor is called C-curve. The variance of C-curve in a 'tanks in series model' comprising of 'm' tanks is equal to
347
The eddy diffusivity for a liquid in plug flow must be
348
For multiple reactions, the flow pattern within the vessel affects the
349
The rate expression for the gaseous phase reaction, CO + 2H2 --> CH3OH, is given by, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/477-488-1.png . Which of the following is not possible ?
350
For the same residence time, which one will give the maximum conversion ?
351
__________ gas is normally employed in B.E.T.method of finding out the surface area of catalyst.
352
The exit age distribution curve E(t) for an ideal CSTR with the average residence time, τ, is given by
353
The rate constant of a reaction depends on the
354
For the reversible reaction A <-->2B, if the equilibrium constant K is 0.05 mole/litre; starting from initially 2 moles of A and zero moles of B, how many moles will be formed at equilibrium ?
355
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
356
Time required for 50% decomposition of a liquid in an isothermal batch reactor following first order kinetics is 2 minutes. The time required for 75% decomposition will be about __________ minutes.
357
For a __________ order reaction, the units of rate constant and rate of reaction are the same.
358
In case of staged packed bed reactors carrying out exothermic reaction, use
359
Vegetable oils are hydrogenated in a __________ reactor.
360
Pure A in gas phase enters a reactor 50% of this A is converted to B through the reaction, A --> 3B. Mole fraction of A in the exit stream is
361
The rate of reaction does not decrease appreciably as the reaction proceeds in case of __________ reactions.
362
For all positive reaction orders for a particular duty,
363
The heat of reaction
364
Which of the following does not produce a change in the value of rate constant of a reaction ?
365
With increase in temperature, the equilibrium conversion of a reversible exothermic reaction
366
In a CSTR __________ varies with time.
367
The following gas phase reactions are carried out isothermally in a CSTR.
A --> 2R ; r1 = k1pA ;
k1 = 20mole/(sec.m3 bar)
A --> 3S ; r2 = k2 pA ;
k2 = 40mole/(sec.m3 .bar)
What is the maximum possible value of FR(mole/sec.) ?
368
As the chemical reaction proceeds, the rate of reaction
369
Pick out the wrong statement.
370
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 from 10 moles/litre to 5 moles/litre in the same volume.
371
Photo-chemical reactions occur in presence of
372
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
373
Knudsen diffusion is directly proportional to
374
Fractional conversion __________ for an exothermic reversible chemical reaction, when the temperature is maximum.
375
Non-catalytic fluid-solid reactions are represented by __________ model.
376
A pulse tracer is introduced in an ideal CSTR (with a mean residence time ι) at time, t = 0. The time taken for the exit concentration of the tracer to reach half of its initial value will be
377
On application of pressure to the equilibrium system, ice <--> water ; which of the following phenomenon will occur ?
378
Participation of __________ is involved in the occurrence of a chemical reaction.
379
Promoter.
380
The rate constant of a reaction is a function of the
381
Mean residence time is equal to the space time, when
382
If 'n' is the order of reaction, then unit of rate constant is
383
Batch process is preferred over continuous process, when the
384
The value of 'n' for a chemical reaction A --> B, whose reaction rate is -->CAn, will be __________ if the rate of the reaction increases by a factor of 8, when the concentration of is doubled.
385
With the same reaction time, initial concentration and feed rate, the reaction 2A -->B is carried out separately in CSTR and P.F. reactor of equal volumes. The conversion will be
386
For any reaction, we may write conversion as a function of
387
The use of space time is preferred over the mean residence time in the design of a/an
388
Autocatalytic reactions are best carried out in a
389
The gas phase reaction 2A <--> B is carried out in an isothermal plug flow reactor. The feed consists of 80 mole % A and 20 mole % inerts. If the conversion of A at the reactor exit is 50%, then CA/CA0 at the outlet of the reactor is
390
A batch reactor suffers from following disadvantage.
391
A first order reaction is to be treated in a series of two mixed reactors. The total volume of the two reactors is minimum, when the reactors are
392
A second order liquid phase reaction, A -->B, is carried out in a mixed flow reactor operated in semi batch mode (no exit stream). The reactant A at concentration CAF is fed to the reactor at a volumetric flow rate of F. The volume of the reacting mixture is V and the density of the liquid mixture is constant. The mass balance for A is
393
Half life period of a chemical reaction is proportional to CA0-1 , if the reaction is of __________ order.
394
The irreversible reaction, X --> Y, is the special case of the reversible reaction, X <-->Y, in which the
395
The equilibrium constant K of a chemical reaction depends on
396
The reaction rate almost gets doubled for 10°C rise in temperature. This is due to the fact that the
397
Which of the following is not a unit of reaction rate ?
398
Brunaur, Emmet and Teller (BET) equation is used to determine the specific surface area of a porous particle but not the pore volume & the porosity of the catalyst bed. Which of the following postulates is not used to derive BET equation ?
399
The sequence in which three CSTR's of volumes 5, 10 and 15 m3 will be connected in series to obtain the maximum production in a second order irreversible reaction is
400
The following half life data are available for the irreversible liquid phase reaction A products.
https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/470-419-1.png The overall order of reaction is
401
A non-catalytic chemical reaction of the type https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/457-279-1.png is called a __________ reaction.
402
The unit of frequency factor in Arhenious equation is
403
With increase in the order of reaction (for all positive reaction orders), the ratio of the volume of mixed reactor to the volume of plug flow reactor (for identical feed composition, flow rate and conversion)
404
Reaction of benzene with chlorine gas to produce tri-chlorobenzene exemplifies a/an __________ reaction.
405
For the gaseous reaction 2A --> B, where the feed consists of 50 mole % A and 50 mole % inerts, the expansion factor is
406
The molecularity and the order of reaction respectively, for the hydrolysis of methyl acetate in presence of acids are
407
The irreversible reaction is a special case of reversible reaction, if the
408
A pollutant P degrades according to first order kinetics. An aqueous stream containing P at 2 kmole/m3 and volumetric flow rate 1m3 /h requires a mixed flow reactor of volume V to bring down the pollutant level to 0.5 kmole/m3 . The inlet concentration of the pollutant is now doubled and the volumetric flow rate is tripled. If the pollutant level is to be brought down to the same level of 0.5 kmole/m3 , the volume of the mixed flow reactor should be increased by a factor of
409
For the liquid phase parallel reactions:
R, rR = K1.CA2; E1 = 80 KJ/mole
S, rs= K1.CA ; E2 = 120 KJ/mole
The desired product is R. A higher selectivity of R will be achieved, if the reaction is conducted at
410
In an ideal mixed reactor (at steady state), the
411
The knowledge of initial concentration and rate constant is necessary to determine the half life time of a reaction of __________ order.
412
Which of the following factors control the design of a fluid-solid reactor ?
413
A Catalyst
414
The reaction rate constants at two different temperature T1 and T2 are related by
415
The synthesis of proteins and metabolism in biological objects occur in the presence of biocatalyst called
416
Pick out the wrong statement.
417
Kinetics of a catalytic reaction can be best studied on a/an __________ reactor.
418
In case of a __________ reactor, the composition in the reactor and at the exit of the reactor is the same.
419
Exothermic reactions are best carried out in
420
What is the order of chemical reaction https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/449-166-1.png , if itis found that the reaction rate doubles on doubling the concentration of B and also the reaction rate doubles when the concentrations of both A & B were doubled and quandrupled when the concentrations of both B & C were doubled ?
421
Reactions with high activation energy are
422
If n = overall order of a chemical reaction. a = initial concentration of reactant. t = time required to complete a definite fraction of the reaction. Then pick out the correct relationship.
423
In case of a/an __________ chemical reaction, conversion increases with the rise in temperature.
424
A space velocity of 5 hr-1 means that
425
With increase in initial concentration, the fractional conversion of a first order reaction in a given time
426
The rate of reaction of a/an __________ reaction is not affected by temperature rise.
427
With an increase in pressure in gaseous phase chemical reactions, the fractional conversion __________ when the number of moles decreases.
428
Half-life period for a first order reaction is __________ the initial concentration of the reactant.
429
Carbon particles accummulated on the catalyst used in the gas oil cracking lies in the category of __________ poison.
430
The order of the chemical reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/448-163-1.png , whose rate equation is given as -rA= KCA2. CB is
431
What is the dispersion number for a plug flow reactor ?
432
The decomposition of A into B is represented by the exothermic reaction, A <--> 2B. To achieve maximum decomposition, it is desirable to carry out the reaction.
433
The catalytic converter for conversion of SO2 to SO3 by contact process should have a feed with SO2 content between
434
If the pore diffusion controls in a catalytic reaction, the apparent activation energy Ea is equal to
435
With increase in K2/K1 in case of a unimolecular type elementary reactions https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/449-170-1.png , the fractional yield of 'R' in mixed reactor (for a given conversion of 'A')
436
Collision theory gives the rate constant for bimolecular reaction as
437
Find a mechanism that is consistent with the rate equation and reaction given below:
2A + B --> A2B, ( - rA) = k.CA.CB
438
A gaseous reactant is introduced in a mixed reactor of 3 litres volume at the rate of 1 litre/second. The space time is __________ seconds.
439
The temperature dependence of reaction rate constant (K) by Arhenius law is given by
440
For a __________ order chemical reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/449-169-1.png , the fractional conversion of reactant 'A' is proportional to time.
441
Velocity of a chemical reaction
442
Backmixing is most predominant in
443
If helium is introduced in a reactor containing O2, SO2 and SO3 at equilibrium, so that total pressure increases while volume and temperature remains constant. In this case the dissociation of SO3 (as per Le Chatlier principle)
444
Consider a reversible exothermic reaction in a plug flow reactor. The maximum and minimum permissible temperatures are Tmax and Tmin respectively. Which of the following temperature (T) profiles will require the shortest residence time to achieve the desired conversion.
445
Fluidised bed reactor is characterised by
446
In which of the following gaseous phase reversible reactions, the product yield can not be increased by the application of high pressure ?
447
Space time equals the mean residence time
448
A liquid decomposes by irreversible first order kinetics and the half life period of this reaction is 8 minutes. The time required for 75% conversion of the liquid will be __________ minutes.
449
Rate constant 'k' and absolute temperature 'T' are related by collision theory (for bimolecular) as
450
The conversion for a first order liquid phase reaction. A --> B in a CSTR is 50%. If another CSTR of the same volume is connected in series, then the % conversion at the exit of the second reactor will be
451
What is the dispersion number for a CSTR?
452
Rate of a chemical reaction is independent of the concentration of the reactants for a __________ reaction.
453
With increase in temperature, the rate constant obeying Arhenious equation
454
Bulk diffusion in catalyst pore __________ with increase in pressure.
455
Pick out the correct statement.
456
The concentration of A in a first order reaction, A --> B, decreases
457
The equilibrium constant of chemical reaction __________ in the presence of catalyst.
458
The order of a chemical reaction is
459
A chemical reaction occurs, when the energy of the reacting molecules is __________ the activation energy of reaction.
460
In the hydrodealkylation of toluene to benzene, the following reactions occur:
C7H8 + H2 --> C6H6 + CH4
2C6H6 <--> C12H10 + H2
Toluene and hydrogen are fed to a reactor in a molar ratio 1:5.80% of the toluene gets converted and the selectivity of benzene(defined as moles of benzene formed/moles of toluene converted) is 90%. The fractional conversion of hydrogen is
461
Catalyst is a substance, which __________ chemical reaction.
462
The residence time distribution of an ideal CSTR is
463
A rise in temperature
464
The enzyme which can catalyse the conversion of glucose to ethyl alcohol is
465
For reaction, P + 2 -->3R, molar rate of consumption of P is
466
If pore diffusion is the controlling step in a solid catalysed reaction, the catalyst
467
The conversion of a reactant, undergoing a first order reaction, at a time equal to three times the half life of the reaction is
468
In case of unimolecular type elementary reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/449-176-1.png , plug flow reactor as compared to mixed reactor is
469
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 ?
470
The first order series reaction https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/473-457-1.png is conducted in a batch reactor. The initial concentrations of A, B and C (CA0, CB0, CC0 respectively) are all non-zero. The variation of CB with reaction time will not show a maximum, if
471
A second order reaction of the form A + B --> C is called a pseudo-first order reaction, when
472
Pick out the wrong statement.
473
Effectiveness factor (E) of a catalyst pellet is defined as https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/458-294-1.png , Effectiveness factor for a first order reaction is given by (where, T = Thiele modulus)
474
Inversion of cane sugar is an example of
475
Pick out the correct statement.
476
In which of the following gaseous phase reactions, the equilibrium of the reaction remains unaffacted by pressure changes ?
477
The mean conversion in the exit stream, for a second order, liquid phase reaction in a non-ideal flow reactor is given by
478
Integral method for analysing the kinetic data is used
479
Concentration of the limiting reactant (with initial concentration of a moles/litre) after time t is (a-x). Then 't' for a first order reaction is given by
480
The rate of a gas phase reaction is given by K . CA . CB. If the volume of the reaction vessel is reduced to l/4th of its initial volume, then the reaction rate compared to the original rate will be __________ times.
481
Rate of a chemical reaction is not affected by the
482
Overall rate of reaction in a heterogenous catalytic reaction depends upon the mass and energy transfer from the fluid to solid surface and its rate of reaction is usually __________ the concentration of catalyst, if it does not entail a chain mechanism.
483
__________ resistance is not involved in the combustion of a carbon particle.
484
In an ideal P.F.R. at steady state conditions
485
B.E.T. method of finding out surface area of a catalyst, uses the extension of __________ isotherm.
486
In a chemical reaction, repesented by, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/454-241-1.png , it is observed that the
(i) rate of reaction increases by a factor of 4 on doubling the concentration of the reactant.
(ii) rate of reaction increases by a factor of 9 on trebling the concentration of the reactant.
Then the rate of the reaction is proportional to(where, CA = contentration of the reactant)
487
Which of the following holds good for an elementary reaction,https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/455-249-1.png ?
488
An example of autothermal reactor operation is
489
For a packed bed reactor; the presence of a long tail in the residence time distribution curve is an indication of
490
Space time in flow reactor is
491
For a first order isothermal chemical reaction in a porous catalyst, the effectiveness factor is 0.3. The effectiveness factor will increase if the
492
Cold shot cooling is only practical when the feed temperature is __________ than the reaction temperature.
493
The following gas phase reaction is taking place in a plug flow reactor. https:/ /www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/478-498-1.png
A stoichiometric mixture of A and B at 300 K is fed to the reactor. At 1 m along the length of the reactor, the temperature is 360 K. The pressure drop is negligible and an ideal gas behaviour can be assumed. Identify the correct expression relating the concentration of A at the inlet (CA0), concentration of A at 1m (CA) and the corresponding conversion of A (X).
494
The preferred reacting system for oxidation of o-xylene to phthalic anhydride is
495
The effectiveness factor for large value of Thiele modulus (L.sqrt(K/D1)) of a solid catalysed first order reaction is equal to (where, L = length of the reactor, cm, D1 = diffusion co-efficient, cm2/second)
496
A first order reaction A B occurs in an isothermal porous catalyst pellet of spherical shape. If the concentration of A at the centre of the pellet is much less than at the external surface, the process is limited by
497
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. https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/477-486-1.png
