(4) Chemical Reactions Engineering Flashcards
1
Q
Which of the following will give maximum gas conversion?
A
2
Q
__________ explains the mechanism of catalysis.
A
3
Q
From among the following, choose one which is not an exothermic process.
A
4
Q
The fractional volume change of the system for the isothermal gas phase reaction, A 3B , between no conversion and complete conversion is
A
5
Q
A catalyst
A
6
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
7
Q
For high conversion in a highly exothermic solid catalysed reaction, use a __________ bed reactor.
A
8
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
9
Q
The single parameter model proposed for describing non-ideal flow is the __________ model.
A
10
Q
A first order reaction requires two equal sized CSTR. The conversion is
A
11
Q
In case of physical adsorption, the heat of adsorption is of the order of __________ kcal/kg.mole.
A
12
Q
The most unsuitable reactor for carrying out reactions in which high reactant concentration favours high yields is
A
13
Q
Pick out the wrong statement pertaining to space velocity of flow reactors.
A
14
Q
A reactor is generally termed as an autoclave, when it is a
A
15
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
16
Q
The rate constant of a chemical reaction decreases by decreasing the
A
17
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
18
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
19
Q
__________ is the response curve for a step input signal from a reactor.
A
20
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
21
Q
Which of the following is the most suitable for very high pressure gas phase reaction ?
A
22
Q
The reaction between oxygen and organic material is a/an __________ reaction.
A
23
Q
With decrease in temperature, the equilibrium conversion of a reversible endother-mic reaction
A
24
Q
In an exothermic chemical reaction, the reactants compared to the products have
A
25
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
26
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
27
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
28
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
29
A batch reactor is suitable for
30
For a heterogeneous catalytic reaction
31
The increase in the rate of reaction with temperature is due to
32
A catalyst loses its activity due to
33
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.
34
Specific rate constant for a second order reaction
35
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
36
For an isothermal variable volume batch reactor, the following relation is applicable for a first order irreversible reaction.
37
For a zero order chemical reaction, the
38
BET apparatus
39
Radioactive decay follows __________ order kinetics.
40
The excess energy of reactants in a chemical reaction required to dissociate into products is termed as the __________ energy.
41
For a solid catalysed chemical reaction, the effectiveness of solid catalyst depends upon the __________ adsorption.
42
Pick out the correct statement.
43
The dimensions of rate constant for reaction 3A --> B are (l/gm mole)/min. Therefore the reaction order is
44
Pick out the correct statement
45
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
46
Sulphuric acid is used as a catalyst in the
47
Fractional conversion __________ with increase in pressure for ammonia synthesis reaction i.e., N2 + 3H2 <->2NH3.
48
Pick out the wrong statement.
49
The reason why a catalyst increases the rate of reaction is that, it
50
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.
51
When the density of the reaction mixture is constant in a chemical reaction, the ratio of the mean residence time to space time is
52
In an ideal tubular-flow reactor
53
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?
54
__________ is the controlling step in a highly temperature sensitive fluid-solid non-catalytic reaction.
55
An autothermal reactor is
56
The rate constant of a first order reaction depends on the
57
A reaction in which one of the products of reaction acts as a catalyst is called a/an __________ reaction.
58
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
59
Which of the following will favour the reverse reaction in a chemical equilibrium reaction ?
60
Conversion increases with increase in temperature in case of a an __________ reaction.
61
Effective diffusivity (DE) in a catalyst pellet is related to molecular diffusivity (DN) and Knudsen diffusivity (DK) as
62
A photochemical reaction is __________ light.
63
Pick out the wrong statement.
64
In a/an __________ reactor, there is exchange of heat with the surroundings with sizeable temperature variation.
65
Unreacted core model' represents the reaction involving
66
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).
67
If a solid-gas non-catalytic reaction occurs at very high temperature, the rate controlling step is the __________ diffusion.
68
The units of frequency factor in Arhenious equation
69
Which of the following is not a chemical step in a fluid solid catalytic reaction ?
70
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
71
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:
72
In case of __________ reactions, the reaction rate does not decrease appreciably as the reaction proceeds.
73
For nearly isothermal operation involving large reaction time in a liquid-phase reaction, the most suitable reactor is a __________ reactor.
74
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 ?
75
B.E.T. method can be used to determine the __________ of a porous catalyst.
76
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
77
Which of the following is an independent variable for a batch tank reactor with uniform concentration and temperature?
78
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
79
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.
80
In a reversible chemical reaction having two reactants in equilibrium, if the concentration of the reactants are doubled, then the equilibrium constant will
81
The equilibrium constant of a catalytic chemical reaction __________ due to the presence of a catalyst.
82
The rate constant of a chemical reaction increases by increasing the
83
The catalytic activity of enzymes is due to their capacity to lower the __________ energy.
84
A first order reaction requires two unequal sized CSTR. Which of the following gives higher yield ?
85
Pick out the correct statement.
86
The effect of increasing pressure on the gaseous equilibrium of the reaction 2X+3Y <-->3X+2Y indicates that
87
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
88
A batch reactor is characterised by
89
When a catalyst increases the rate of forward reaction, the value of rate constant
90
Rate determining step in a reaction consisting of a number of steps in series is the __________ step.
91
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.
92
A catalyst in a chemical reaction __________ free energy change in the reaction.
93
Signal normally used to study non-ideal flow by stimulus response technique is __________ input.
94
When all the limiting reactant is consumed in the reaction, the operational yield __________ the relative yield.
95
The half life period of a first order reaction is
96
The catalyst in a second order reversible reaction increases the rate of the forward reaction
97
Catalyst carriers
98
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.
99
A high space velocity means that a given
100
In flow reactors, the performance equations interrelate the rate of reaction to the
101
Space velocity
102
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 ?
103
A reaction which is catalysed by a base is catalysed by all substances which have a tendency to
104
For a homogeneous reaction of nth order, the dimension of the rate constant is given by
105
The fractional volume change between no conversion and complete conversion, for the isothermal gas phase reaction, 2A-->R, is
106
The reaction in which one of the products of reaction acts as a catalyst is called a/an __________ reaction.
107
A typical example of an exothermic reversible reaction conducted at high pressure in industry is
108
Study of chemical kinetics is the easiest in the case of __________ reactions.
109
In autocatalytic reactions,
110
Semibatch reactor is preferred, when a/an
111
Exposure of a photographic plate to produce a latent image is an example of __________ reaction.
112
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
113
Helium-mercury method is used for the measurement of the __________ of the catalyst.
114
What is the order of a chemical reaction whose rate is deter-mined by the variation of one concentration term only?
115
Pick out the wrong statement.
116
The rate at which a chemical substance reacts is proportional to its
117
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
118
A plug-flow reactor is characterised by
119
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.
120
For a tubular reactor with space time 'τ' and residence time 'θ', the following statement holds good.
121
Rate of an autocatalytic chemical reaction is a function of
122
Which of the following curves shows the effect of temperature on the extent of gas-solid adsorption at a given pressure?
123
For an ideal mixed flow reactor (CSTR), the exit age distribution E(t) is given by
124
Fluid flow in a real packed bed can be approximated as __________ model.
125
For series reaction, the relative yield
126
The 'E' curve for a non-ideal reactor defines the fraction of fluid having age between t and t + dt
127
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
128
A reaction which is catalysed by an acid is also catalysed by any substance, which has a tendency to
129
A stirred tank reactor compared to tubular-flow reactor provides
130
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
131
A catalyst inhibitor
132
In chamber process of sulphuric acid manufacture in industry, the gas phase oxidation of SO2 to SO3 is accomplished by a __________ reaction.
133
If the rate of a chemical reaction becomes slower at a given temperature, then the
134
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 ?
135
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
136
The value of steric factor 'P' in the equation k = PZe^E/RT usually ranges from
137
For a zero order reaction, the concentration of product increases with the
138
Pick out the wrong statement.
139
Effectiveness factor of a catalyst pellet is a measure of the __________ resistance.
140
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)
141
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
142
Differential method for analysing the kinetic data is used
143
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
144
The reaction in which the rate equation corresponds to a stoichiometric equation, is called a/an __________ reaction.
145
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
146
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
147
Arrhenious equation represents graphically the variation between the __________ and temperature.
148
__________ catalytic reaction is involved in the thermal cracking of gas oil.
149
Variables affecting the rate of homogeneous reactions are
150
A chemical reaction occurs when the energy of the reacting molecules is __________ the activation energy of the reaction.
151
Which of the following resistances is not involved in a gas phase catalytic (gas-solid) reaction?
152
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
153
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
154
If CA is the quantity of reactants initially present, the quantity left after 'n' half periods will be equal to
155
A photochemical reaction is
156
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.)
157
The optimum performance for reactors operating in parallel is obtained when the feed stream is distributed in such a way, that the
158
A catalyst is said to be a negative catalyst, ifit
159
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.
160
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
161
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
162
Pick out the wrong statement.
163
A backmix reactor
164
Rate of a chemical reaction is not influenced by the
165
Pick out the wrong statement:
166
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))
167
Which of the following is not a theory of homogeneous reaction?
168
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
169
In a semi-batch reactor,
170
Most important characteristics of gas-liquid reactors are the
171
Which of the following is a controlling factor in very fast heterogeneous reaction?
172
Enzymes are destroyed, when the
173
For an autocatalytic reactor, the suitable reactor set up is
174
Ionic reactions occur in
175
Sometimes, batch process is preferred over continuous process, when the product
176
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?
177
The half life period of a first order reaction is given by (where, K = rate constant. )
178
Half life period of a chemical reaction is
179
In the gaseous phase ammonia formation reaction (N2 + 3H2<-->2NH3), the value of the equilibrium constant depends on the
180
Transition state theory relates the above quantities as
181
Photochemical reaction rate does not depend significantly on temperature, because
182
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
183
According to the 'law of mass action', the rate of reaction is directly proportional to the
184
In a chemical reaction, __________ are conserved.
185
For an ideal gas mixture undergoing a reversible gaseous phase chemical reaction, the equilibrium constant
186
In the reversible reaction of the type, A + B <--> AB, in general
187
A batch reactor is
188
For a first order reaction carried out in a plug flow reactor, the space time is
189
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
190
A chemical reaction is of zero order, when the reaction rate is (where, CA = concentration of reactant)
191
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)?
192
Pick out the wrong statement.
193
There is no correspondence between stoichiometry and the rate equation in case of a/an __________ reaction.
194
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?
195
Which of the following is used for calcination of limestone and dolomite in industrial practice ?
196
An imbalanced chemical reaction equation is against the law of
197
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 ?
198
Which of the following is a characteristic of an ideal plug flow reactor ?
199
Velocity of a reaction depends upon the
200
Threshold energy in a reaction is equal to the
201
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
202
Design of heterogeous catalytic reactor involves consideration of __________ steps.
203
A consecutive reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/446-133.png , is characterised by
204
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 ?
205
For a fluidised bed reactor, the most suitable/relevant model is a __________ model.
206
The rate at which a chemical substance reacts is proportional to its
207
In a reaction, the threshold energy is equal to (where, A = activation energy N = normal energy of reactants)
208
Thermodynamic equilibrium constant in a system is affected by
209
The most suitable reactor for carrying out an auto-thermal reaction is a
210
Which of the following chemical reactions will be favoured by low pressure ?
211
A catalyst in a chemical reaction
212
Slurry reactors are characterised by the
213
Limiting reactant in a chemical reaction decides the
214
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 ?
215
The rate of forward reaction, at chemical equilibrium is____the rate of backward reaction.
216
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 .
217
With increase in temperature, the equilibrium __________ rises in case of endothermic reaction.
218
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.
219
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
220
Considering the endotheomic dissociation of CaCO3 in a closed vessel (CaCO3 <-->CaO + CO2), the pressure of CO2 increases, if
221
The exit age distribution of fluid leaving a vessel is used to know the
222
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
223
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.
224
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
225
The time needed to achieve the same fractional conversion for particles of different sizes (d) when chemical reaction controls, is proportional to
226
A balanced chemical reaction equation conforms to the law of
227
An exothermic reaction takes place in an adiabatic reactor. The product temperature __________ reactor feed temperature.
228
Reverse reaction in a chemical equilibrium is favoured by the
229
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
230
Sum of the powers of the concentration terms in the rate equation is called the __________ of the reaction.
231
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
232
The role of a catalyst in a chemical reaction is to change the
233
The vessel dispersion number (D/μL) for plug flow is
234
Molecularity of a reaction
235
BET apparatus is used to determine the
236
Carrier in a catalyst increases its
237
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
238
When the reaction occurs in the diffusion controlled region, the apparent activation energy as measured is only __________ the true value.
239
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.
240
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
241
Kinetics of a solid catalysed reaction can best be studied in a __________ reactor.
242
According to Arhenious equation of temperature dependency of rate constant for an elementary reaction
243
The reactions of high molecularity are rare, because
244
Which of the following is the most suitable for isothermal operation ?
245
For a first order chemical reaction, the rate constant
246
Which of the following is an autocatalytic reaction ?
247
The performance of a cascade of CSTR's can be improved by adding
248
A multiple reaction may be classified as a __________ reaction.
249
Holding time for flow reactors is __________ the space time, for constant fluid density
250
Pick out the wrong statement.
251
The order of the reaction, https://www.indiabix.com/_files/images/chemical-engineering/chemical-reaction-engineering/448-162-1.png , is
252
Arhenious equation shows the variation of __________ with temperature.
253
When a catalyst increases the rate of chemical reaction, the rate constant
254
In which of the following reactions, the equilibrium will shift to the right, if the total pressure is increased?
255
The catalyst in a first order chemical reaction changes the
256
Oil is hydrogenated using nickel catalyst in a __________ reactor.
257
The performance equations for constant density systems are identical for
258
Reaction rate of a first order reaction, which is half completed in 23 minutes will be
259
Which of the following is the optimum operating condition for an exothermic reversible reaction taking place in a plug-flow reactor ?
260
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
261
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
262
In case of calcination of limestone, CaCO3 CaO + CO2, the addition of more of CaO will result in __________ in the concentration of CO2.
263
The rate of a homogeneous reaction is a function of
264
In the fluid catalytic cracker (FCC), the cracking reaction is __________ (A) and the regeneration is___(B) __________
265
Pick out the correct statement.
266
Promoter is added to the catalyst to improve its
267
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
268
When a high liquid hold up is required in a reactor for gas liquid reaction, use __________ coloumn.
269
In an exothermic reaction, the energy of the reacting substances as compared to that of products is
270
For a tubular flow reactor with uniform concentration and temperature, the independent variable is
271
Pick out the wrong statement.
272
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
273
The extent of a reaction is
274
Higher free energy of activation of a chemical reaction (at a given temperature) implies
275
Calcination reaction of limestone (CaCO3 --> CaO + CO2) goes to completion in the rotary kiln, because
276
The reactions with low activation energy are
277
Molecularity of an elementary reaction, P + Q --> R + S is
278
Which of the following is not endothermic in nature ?
279
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
280
The space time is equivalent to the holding time in a steady state mixed reactor for
281
The dispersion number of perfect mixed flow is
282
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 ?
283
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.
284
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
285
Half life period of a first order irreversible reaction A B is
286
Pick out the wrong statement.
287
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.)
288
Pick out the wrong statement
289
The energy of activation of a chemical reaction
290
Chemical kinetics can predict the __________ of a chemical reaction.
291
Which of the following fixes the volume of a batch reactor for a particular conversion and production rate?
292
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.
293
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.
294
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
295
With increase in the space time of an irreversible isothermal reaction being carried out in a P.F. reactor, the conversion will
296
A catalyst promoter
297
In case of a P.F.R., there
298
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.
299
If ΔG (free energy change) for a chemical reaction is very large and negative, then the reaction is
300
In a zero order reaction, reactants concentration does not change with time and the
301
The minimum energy required to allow a chemical reaction to proceed is termed as the 'threshold energy '. Chemical reaction with low activation energy are
302
If Thiele modulus is __________ , then the pore diffusion resistance in a catalyst may be considered as negligible.
303
From collison theory, the reaction rate constant is proportional to
304
For a mixed flow reactor operating at steady state, the rate of reaction is given by
305
Catalytic action in a catalytic chemical reaction follows from the ability of catalyst to change the
306
In Langmuir treatment of adsorption,
307
Organic catalysts differ from the inorganic catalyst in the sense that the former is
308
An endothermic aqueous phase first order irreversible reaction is carried out in an adiabatic plug flow reactor. The rate of reaction
309
Pick out the wrong statement.
310
For an ideal plug flow reactor, the value of Peclet number is
311
An endothermic second order reaction is carried out in an adiabatic plug flow reactor. The rate of heat generation is
312
Equilibrium of a chemical reaction as viewed by kinetics is a __________ state.
313
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.
314
The size of plug flow reactor (PFR) for all positive reaction orders and for any given duty, is __________ that of mixed reactor.
315
A space time of 3 hours for a flow reactor means that
316
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
317
The experimentally determined overall order of the reaction, A + B --> C + D, is two. Then the
318
In a continuous flow stirred tank reactor, the composition of the exit stream
319
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.
320
The energy balance equation over a tubular reactor under transient conditions is
321
Which of the following factors control the deactivation of a porous catalyst pellet ?
322
For the reaction, A + B -->2B + C,
323
Transition state theory gives the rate constant as
324
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 ?
325
Pick out the wrong statement.
326
In a reversible reaction, a catalyst increases the rate of forward reaction
327
Maximum equilibrium conversion for endothermic reaction is obtained at the __________ temperature.
328
When an exothermic reversible reaction is conducted adiabatically, the rate of reaction
329
For a first order chemical reaction in a porous catalyst, the Thiele modulus is 10. The effectiveness factor is approximately equal to
330
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
331
In solid catalysed reactions the diffusional effects are more likely to affect the overall rate of reaction for
332
Helium-mercury method can be used to determine the __________ of the catalyst particle.
333
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' ?
334
Chemical reaction rate of a component depends upon the
335
In a semi-batch reactor
336
A trickle bed reactor is the one, which
337
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 ?
338
The excess energy of the reactants required to dissociate into products is known as the __________ energy.
339
In a/an __________ vessel, the fluid enters and leaves following plug flow.
340
Shift conversion reaction
341
The importance of diffusion in a catalyst are increased by
342
A back mix reactor is
343
Which one is the rate controlling step in a solid-gas non-catalytic reaction occurring at very high temperature?
344
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
345
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.
346
The ratio of moles of a reactant converted into the desired product to that converted into unwanted product is called
347
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
348
The eddy diffusivity for a liquid in plug flow must be
349
For multiple reactions, the flow pattern within the vessel affects the
350
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 ?
351
For the same residence time, which one will give the maximum conversion ?
352
__________ gas is normally employed in B.E.T.method of finding out the surface area of catalyst.
353
The exit age distribution curve E(t) for an ideal CSTR with the average residence time, τ, is given by
354
The rate constant of a reaction depends on the
355
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 ?
356
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
357
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.
358
For a __________ order reaction, the units of rate constant and rate of reaction are the same.
359
In case of staged packed bed reactors carrying out exothermic reaction, use
360
Vegetable oils are hydrogenated in a __________ reactor.
361
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
362
The rate of reaction does not decrease appreciably as the reaction proceeds in case of __________ reactions.
363
For all positive reaction orders for a particular duty,
364
The heat of reaction
365
Which of the following does not produce a change in the value of rate constant of a reaction ?
366
With increase in temperature, the equilibrium conversion of a reversible exothermic reaction
367
In a CSTR __________ varies with time.
368
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.) ?
369
As the chemical reaction proceeds, the rate of reaction
370
Pick out the wrong statement.
371
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.
372
Photo-chemical reactions occur in presence of
373
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
374
Knudsen diffusion is directly proportional to
375
Fractional conversion __________ for an exothermic reversible chemical reaction, when the temperature is maximum.
376
Non-catalytic fluid-solid reactions are represented by __________ model.
377
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
378
On application of pressure to the equilibrium system, ice <--> water ; which of the following phenomenon will occur ?
379
Participation of __________ is involved in the occurrence of a chemical reaction.
380
Promoter.
381
The rate constant of a reaction is a function of the
382
Mean residence time is equal to the space time, when
383
If 'n' is the order of reaction, then unit of rate constant is
384
Batch process is preferred over continuous process, when the
385
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.
386
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
387
For any reaction, we may write conversion as a function of
388
The use of space time is preferred over the mean residence time in the design of a/an
389
Autocatalytic reactions are best carried out in a
390
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
391
A batch reactor suffers from following disadvantage.
392
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
393
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
394
Half life period of a chemical reaction is proportional to CA0-1 , if the reaction is of __________ order.
395
The irreversible reaction, X --> Y, is the special case of the reversible reaction, X <-->Y, in which the
396
The equilibrium constant K of a chemical reaction depends on
397
The reaction rate almost gets doubled for 10°C rise in temperature. This is due to the fact that the
398
Which of the following is not a unit of reaction rate ?
399
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 ?
400
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
401
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
402
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.
403
The unit of frequency factor in Arhenious equation is
404
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)
405
Reaction of benzene with chlorine gas to produce tri-chlorobenzene exemplifies a/an __________ reaction.
406
For the gaseous reaction 2A --> B, where the feed consists of 50 mole % A and 50 mole % inerts, the expansion factor is
407
The molecularity and the order of reaction respectively, for the hydrolysis of methyl acetate in presence of acids are
408
The irreversible reaction is a special case of reversible reaction, if the
409
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
410
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
411
In an ideal mixed reactor (at steady state), the
412
The knowledge of initial concentration and rate constant is necessary to determine the half life time of a reaction of __________ order.
413
Which of the following factors control the design of a fluid-solid reactor ?
414
A Catalyst
415
The reaction rate constants at two different temperature T1 and T2 are related by
416
The synthesis of proteins and metabolism in biological objects occur in the presence of biocatalyst called
417
Pick out the wrong statement.
418
Kinetics of a catalytic reaction can be best studied on a/an __________ reactor.
419
In case of a __________ reactor, the composition in the reactor and at the exit of the reactor is the same.
420
Exothermic reactions are best carried out in
421
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 ?
422
Reactions with high activation energy are
423
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.
424
In case of a/an __________ chemical reaction, conversion increases with the rise in temperature.
425
A space velocity of 5 hr-1 means that
426
With increase in initial concentration, the fractional conversion of a first order reaction in a given time
427
The rate of reaction of a/an __________ reaction is not affected by temperature rise.
428
With an increase in pressure in gaseous phase chemical reactions, the fractional conversion __________ when the number of moles decreases.
429
Half-life period for a first order reaction is __________ the initial concentration of the reactant.
430
Carbon particles accummulated on the catalyst used in the gas oil cracking lies in the category of __________ poison.
431
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
432
What is the dispersion number for a plug flow reactor ?
433
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.
434
The catalytic converter for conversion of SO2 to SO3 by contact process should have a feed with SO2 content between
435
If the pore diffusion controls in a catalytic reaction, the apparent activation energy Ea is equal to
436
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')
437
Collision theory gives the rate constant for bimolecular reaction as
438
Find a mechanism that is consistent with the rate equation and reaction given below:
2A + B --> A2B, ( - rA) = k.CA.CB
439
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.
440
The temperature dependence of reaction rate constant (K) by Arhenius law is given by
441
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.
442
Velocity of a chemical reaction
443
Backmixing is most predominant in
444
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)
445
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.
446
Fluidised bed reactor is characterised by
447
In which of the following gaseous phase reversible reactions, the product yield can not be increased by the application of high pressure ?
448
Space time equals the mean residence time
449
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.
450
Rate constant 'k' and absolute temperature 'T' are related by collision theory (for bimolecular) as
451
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
452
What is the dispersion number for a CSTR?
453
Rate of a chemical reaction is independent of the concentration of the reactants for a __________ reaction.
454
With increase in temperature, the rate constant obeying Arhenious equation
455
Bulk diffusion in catalyst pore __________ with increase in pressure.
456
Pick out the correct statement.
457
The concentration of A in a first order reaction, A --> B, decreases
458
The equilibrium constant of chemical reaction __________ in the presence of catalyst.
459
The order of a chemical reaction is
460
A chemical reaction occurs, when the energy of the reacting molecules is __________ the activation energy of reaction.
461
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
462
Catalyst is a substance, which __________ chemical reaction.
463
The residence time distribution of an ideal CSTR is
464
A rise in temperature
465
The enzyme which can catalyse the conversion of glucose to ethyl alcohol is
466
For reaction, P + 2 -->3R, molar rate of consumption of P is
467
If pore diffusion is the controlling step in a solid catalysed reaction, the catalyst
468
The conversion of a reactant, undergoing a first order reaction, at a time equal to three times the half life of the reaction is
469
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
470
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 ?
471
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
472
A second order reaction of the form A + B --> C is called a pseudo-first order reaction, when
473
Pick out the wrong statement.
474
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)
475
Inversion of cane sugar is an example of
476
Pick out the correct statement.
477
In which of the following gaseous phase reactions, the equilibrium of the reaction remains unaffacted by pressure changes ?
478
The mean conversion in the exit stream, for a second order, liquid phase reaction in a non-ideal flow reactor is given by
479
Integral method for analysing the kinetic data is used
480
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
481
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.
482
Rate of a chemical reaction is not affected by the
483
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.
484
__________ resistance is not involved in the combustion of a carbon particle.
485
In an ideal P.F.R. at steady state conditions
486
B.E.T. method of finding out surface area of a catalyst, uses the extension of __________ isotherm.
487
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)
488
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 ?
489
An example of autothermal reactor operation is
490
For a packed bed reactor; the presence of a long tail in the residence time distribution curve is an indication of
491
Space time in flow reactor is
492
For a first order isothermal chemical reaction in a porous catalyst, the effectiveness factor is 0.3. The effectiveness factor will increase if the
493
Cold shot cooling is only practical when the feed temperature is __________ than the reaction temperature.
494
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).
495
The preferred reacting system for oxidation of o-xylene to phthalic anhydride is
496
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)
497
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
498
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
