GATE CH 2022: Chemical Engineering
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GATE 2022 General Aptitude (GA)
Q.1 – Q.5 Carry ONE mark each.
Q.1 Inhaling the smoke from a burning _________ could _________ you quickly.
(A) tire / tier
(B) tire / tyre
(C) tyre / tire
(D) tyre / tier
Q.2 A sphere of radius r cm is packed in a box of cubical shape.
What should be the minimum volume (in cm3 ) of the box that can enclose the
sphere?
(A) r
8
(B) r
(C) 2r
(D) 8r
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Q.3 Pipes P and Q can fill a storage tank in full with water in 10 and 6 minutes,
respectively. Pipe R draws the water out from the storage tank at a rate of 34
litres per minute. P, Q and R operate at a constant rate.
If it takes one hour to completely empty a full storage tank with all the pipes
operating simultaneously, what is the capacity of the storage tank (in litres)?
(A) 26.8
(B) 60.0
(C) 120.0
(D) 127.5
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Q.4 Six persons P, Q, R, S, T and U are sitting around a circular table facing the
center not necessarily in the same order. Consider the following statements:
P sits next to S and T.
Q sits diametrically opposite to P.
The shortest distance between S and R is equal to the shortest distance
between T and U.
Based on the above statements, Q is a neighbor of
(A) U and S
(B) R and T
(C) R and U
(D) P and S
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Q.5 A building has several rooms and doors as shown in the top view of the building
given below. The doors are closed initially.
What is the minimum number of doors that need to be opened in order to go
from the point P to the point Q?
(A) 4
(B) 3
(C) 2
(D) 1
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Q. 6 – Q. 10 Carry TWO marks each.
Q.6 Rice, a versatile and inexpensive source of carbohydrate, is a critical component
of diet worldwide. Climate change, causing extreme weather, poses a threat to
sustained availability of rice. Scientists are working on developing Green Super
Rice (GSR), which is resilient under extreme weather conditions yet gives higher
yields sustainably.
Which one of the following is the CORRECT logical inference based on the
information given in the above passage?
(A) GSR is an alternative to regular rice, but it grows only in an extreme weather
(B) GSR may be used in future in response to adverse effects of climate change
(C) GSR grows in an extreme weather, but the quantity of produce is lesser than
regular rice
(D) Regular rice will continue to provide good yields even in extreme weather
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A game consists of spinning an arrow around a stationary disk as shown below.
Q.7
When the arrow comes to rest, there are eight equally likely outcomes. It could
come to rest in any one of the sectors numbered 1, 2, 3, 4, 5, 6, 7 or 8 as shown.
Two such disks are used in a game where their arrows are independently spun.
What is the probability that the sum of the numbers on the resulting sectors upon
spinning the two disks is equal to 8 after the arrows come to rest?
(A) 1
16
(B) 5
64
(C) 3
32
(D) 7
64
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Q.8 Consider the following inequalities.
(i) 3p − q < 4
(ii) 3q − p < 12
Which one of the following expressions below satisfies the above two
inequalities?
(A) p + q < 8
(B) p + q = 8
(C) 8 ≤ p + q < 16
(D) p + q ≥ 16
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Q.9 Given below are three statements and four conclusions drawn based on the
statements.
Statement 1: Some engineers are writers.
Statement 2: No writer is an actor.
Statement 3: All actors are engineers.
Conclusion I: Some writers are engineers.
Conclusion II: All engineers are actors.
Conclusion III: No actor is a writer.
Conclusion IV: Some actors are writers.
Which one of the following options can be logically inferred?
(A) Only conclusion I is correct
(B) Only conclusion II and conclusion III are correct
(C) Only conclusion I and conclusion III are correct
(D) Either conclusion III or conclusion IV is correct
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Q.10 Which one of the following sets of pieces can be assembled to form a square
with a single round hole near the center? Pieces cannot overlap.
(A)
(B)
(C)
(D)
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GATE 2022 Chemical Engineering (CH)
Q.11 – Q.35 Carry ONE mark Each
Q.11 The value of (1 + i) , where i = √−1, is
(A) −64i
(B) 64i
(C) 64
(D) −64
x 1 3
Q.12 Given matrix A = y 2 6 , the ordered pair (x, y) for which det(A) = 0 is
3 5 7
(A) (1,1)
(B) (1,2)
(C) (2,2)
(D) (2,1)
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GATE 2022 Chemical Engineering (CH)
Q.13 Let f(x) = e | | , where x is real. The value of at x = −1 is
(A) −e
(B) e
(C) 1
e
(D) −1 e
Q.14 The value of the real variable x ≥ 0, which maximizes the function
f(x) = x e is
(A) e
(B) 0
(C) 1
e
(D) 1
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GATE 2022 Chemical Engineering (CH)
Q.15 For a single component system at vapor-liquid equilibrium, the extensive variables
A, V, S and N denote the Helmholtz free energy, volume, entropy, and number of
moles, respectively, in a given phase. If superscripts (v) and (l) denote the vapor
and liquid phase, respectively, the relation that is NOT CORRECT is
(A) ∂A( ) ∂A( )
=
∂V ( ) , ()
∂V ( ) , ( )
(B) ∂A( ) ∂A( )
=
∂N ( ) , ()
∂N ( ) , ( )
(C) A + PV ( ) A + PV ( )
=
N N
(D) A + TS ( ) A + TS ( )
=
N N
Q.16 Consider turbulent flow in a pipe under isothermal conditions. Let r denote the
radial coordinate and z denote the axial flow direction. On moving away from the
wall towards the center of the pipe, the rz-component of the Reynolds stress
(A) Increases and then decreases
(B) Decreases and then increases
(C) Remains unchanged
(D) Only increases
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GATE 2022 Chemical Engineering (CH)
Q.17 Consider two stationary spherical pure water droplets of diameters d and 2d . CO2
diffuses into the droplets from the surroundings. If the rate of diffusion of CO2 into
the smaller droplet is W mol s-1, the rate of diffusion of CO2 into the larger droplet
is
(A) 2W
(B) 4W
(C) W
(D) 0.5W
Q.18 In soap manufacturing, the triglycerides present in oils and fats are hydrolyzed to
mainly produce
(A) Fatty acids and glycerol
(B) Glycerol only
(C) Fatty acids only
(D) Glycerol and paraffins
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GATE 2022 Chemical Engineering (CH)
Q.19 The chemical formula of Glauber’s salt, used in the Kraft process, is
(A) Na2CO3.10H2O
(B) Na2S2O4.2H2O
(C) Na2HPO4.2H2O
(D) Na2SO4.10H2O
Q.20 Catalytic reforming is commonly used in the petroleum industry to improve fuel
quality. The undesirable reaction in the catalytic reforming of naphtha is
(A) Hydrocracking of paraffins
(B) Dehydrogenation of naphthenes
(C) Isomerization of naphthenes
(D) Cyclization of paraffins
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GATE 2022 Chemical Engineering (CH)
Q.21 A control system on the jacket side of a reactor is shown in the figure. Pressurized
water flows through the jacket to cool the reactor. The heated water flashes in the
boiler. The exothermic reaction heat thus generates steam. Fresh boiler feed water
(BFW) is added to make-up for the loss of water as steam. Assume that all control
valves are air-to-open. The controller action, ‘direct’ or ‘reverse’, is defined with
respect to the controller. Select the option that correctly specifies the action of the
controllers.
(A) PC: Reverse, LC: Direct, TC: Reverse
(B) PC: Direct, LC: Reverse, TC: Direct
(C) PC: Direct, LC: Reverse, TC: Reverse
(D) PC: Reverse, LC: Direct, TC: Direct
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GATE 2022 Chemical Engineering (CH)
Q.22 Liquid flowing through a heat exchanger (HX) is heated. A bypass stream is
provided to control the temperature of the heated exit stream. From the given
plumbing options, the one that provides the most effective temperature control for
large disturbances while avoiding vaporization in the heat exchanger is
(A)
(B)
(C)
(D)
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GATE 2022 Chemical Engineering (CH)
Q.23 The appropriate feedforward compensator, G , in the shown block diagram is
(A) 2 (8s + 1)
G =
3 (5s + 1)
(B) 2 (8s + 1)
G =−
3 (5s + 1)
(C) 3 (5s + 1)
G = e
2 (8s + 1)
(D) 3 (5s + 1)
G =− e
2 (8s + 1)
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GATE 2022 Chemical Engineering (CH)
Q.24 Choose the option that correctly pairs the given measurement devices with the
quantities they measure.
Measurement Measured
S No S No
Device Quantity
I Bourdon Gauge A Temperature
II Orifice Plate meter B Concentration
III Pyrometer C Pressure
IV Colorimeter D Flow rate
V Pirani Gauge E Liquid level
(A) I-E II-C III-D IV-B V-A
(B) I-C II-D III-A IV-B V-C
(C) I-C II-D III-E IV-A V-D
(D) I-D II-C III-A IV-E V-C
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GATE 2022 Chemical Engineering (CH)
Q.25 A simple distillation column is designed to separate an ideal binary mixture to
specified distillate and bottoms purities at a given column pressure. If RRmin is the
minimum reflux ratio for this separation, select the statement that is NOT
CORRECT with regard to the variation in the total annualized cost (TAC) of the
column with reflux ratio (RR).
(A) TAC has a minimum with respect to RR
(B) The sharpest rise in TAC occurs as RR approaches RRmin from above
(C) The sharpest decrease in TAC occurs as RR approaches RRmin from above
(D) TAC increases with RR for RR >> RRmin
Q.26 The reaction A → B is carried out isothermally on a porous catalyst. The intrinsic
reaction rate is kC , where k is the rate constant and C is the concentration of A.
If the reaction is strongly pore-diffusion controlled, the observed order of the
reaction is
(A) 1
(B) 2
(C) 3
2
(D) √2
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GATE 2022 Chemical Engineering (CH)
Q.27 In an enzymatic reaction, an inhibitor (I) competes with the substrate (S) to bind
with the enzyme (E), thereby reducing the rate of product (P) formation. The
competitive inhibition follows the reaction mechanism shown below. Let [S] and
[I] be the concentration of S and I, respectively, and r be the rate of consumption
of S. Assuming pseudo-steady state, the correct plot of vs [ ] is
(A)
(B)
(C)
(D)
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GATE 2022 Chemical Engineering (CH)
Q.28 The area of a circular field is 25 m2. The radius, r, is to be determined using the
Newton-Raphson iterative method. For an initial guess of r = 2.500 m, the revised
estimate of r after one iteration is ___________ m (rounded off to three decimal
places).
Q.29 5 moles of liquid benzene, 8 moles of liquid toluene and 7 moles of liquid xylene
are mixed at 25 °C and 1 bar. Assuming the formation of an ideal solution and using
the universal gas constant R = 8.314 J mol-1 K-1, the total entropy change is
__________ J K-1 (rounded off to one decimal place).
Q.30 A perfectly insulated double pipe heat exchanger is operating at steady state.
Saturated steam enters the inner pipe at 100 °C and leaves as saturated water at
100 °C. Cooling water enters the outer pipe at 75 °C and exits at 95 °C. The overall
heat transfer coefficient is 1 kW m-2 K-1 and the heat transfer area is 1 m2. The
average specific heat capacity of water at constant pressure is 4.2 kJ kg-1 K-1. The
required cooling water flow rate is __________ kg s-1 (rounded off to two decimal
places).
Q.31 Consider steady-state diffusion in a binary A-B liquid at constant temperature and
pressure. The mole-fraction of A at two different locations is 0.8 and 0.1. Let N
be the diffusive flux of A calculated assuming B to be non-diffusing, and N be the
diffusive flux of A calculated assuming equimolar counter-diffusion. The quantity
( )
× 100 is____________(rounded off to one decimal place).
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GATE 2022 Chemical Engineering (CH)
Q.32 Consider interphase mass transfer of a species S between two immiscible liquids A
and B. The interfacial mass transfer coefficient of S in liquid A is twice of that in
liquid B. The equilibrium distribution of S between the liquids is given by
y = 0.5y , where y and y are the mole-fractions of S in A and B, respectively.
The bulk phase mole-fraction of S in A and B is 0.10 and 0.02, respectively. If the
steady-state flux of S is estimated to be 10 kmol h-1 m-2, the mass transfer coefficient
of S in A is ________ kmol h-1 m-2 (rounded off to one decimal place).
Q.33 A wet solid containing 20% (w/w) moisture (based on mass of bone-dry solid) is
dried in a tray-dryer. The critical moisture content of the solid is 10% (w/w). The
drying rate (kg m-2 s-1) is constant for the first 4 hours, and then decreases linearly
to half the initial value in the next 1 hour. At the end of 5 hours of drying, the
percentage moisture content of the solid is _________% (w/w) (rounded off to one
decimal place).
Q.34 A process described by the transfer function
(10s 1)
G p ( s)
(5s 1)
is forced by a unit step input at time t = 0. The output value immediately after the
step input (at t = 0 ) is __________ (rounded off to the nearest integer).
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GATE 2022 Chemical Engineering (CH)
Q.35 A compressor with a life of 10 years costs Rs 10 lakhs. Its yearly operating cost is
Rs 0.5 lakh. If the annual compound interest rate is 8%, the amount needed at
present to fund perpetual operation of the compressor is Rs _________ lakhs
(rounded to first decimal place).
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GATE 2022 Chemical Engineering (CH)
Q.36 – Q.65 Carry TWO marks Each
Q.36 The partial differential equation
∂u 1 ∂ u
=
∂t π ∂x
where, t ≥ 0 and x ∈ [0,1], is subjected to the following initial and boundary
conditions:
u(x, 0) = sin ( πx)
u(0, t) = 0
u(1, t) = 0
( . , )
The value of t at which = is
( . , )
(A) 1
(B) e
(C) π
(D) 1
e
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GATE 2022 Chemical Engineering (CH)
Q.37 N moles of an ideal gas undergo a two-step process as shown in the figure. Let P,
V and T denote the pressure, volume and temperature of the gas, respectively. The
gas, initially at state-1 (P , V , T ), undergoes an isochoric (constant volume)
process to reach state-A, and then undergoes an isobaric (constant pressure)
expansion to reach state-2 (P , V , T ). For an ideal gas, C – C = NR, where C
and C are the heat capacities at constant pressure and constant volume,
respectively, and assumed to be temperature independent. The heat gained by the
gas in the two-step process is given by
(A) P (V − V ) + C (T − T )
(B) P (V − V ) + C (T − T )
(C) C (T − T ) + C (T − T )
(D) P V −P V
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GATE 2022 Chemical Engineering (CH)
Q.38 A horizontal cylindrical water jet of diameter D = 2 cm strikes a vertical solid
plate with a hole of diameter D = 1 cm, as shown in the figure. A part of the jet
passes through the hole and the rest is deflected along the plate. The density of water
is 1000 kg m-3. If the speed of the jet is 20 m s-1, the magnitude of the horizontal
force, in N, required to hold the plate stationary is
(A) 30
(B) 10
(C) 20
(D) 5
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GATE 2022 Chemical Engineering (CH)
Q.39 Consider a horizontal rod of radius aR (a < 1) in a stationary pipe of radius R.
The rod is pulled coaxially at a constant velocity V as shown in the figure. The
annular region is filled with a Newtonian incompressible fluid of viscosity . The
steady state fully developed axial velocity profile in the fluid is given by
ln( r / R )
u (r ) V , where r is the radial coordinate. Ignoring end effects, the
ln( a )
magnitude of the pulling force per unit rod length is
(A) V
(B) 2V
ln(a )
(C) 0
(D) V
ln(a )
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GATE 2022 Chemical Engineering (CH)
Q.40 Consider a bare long copper wire of 1 mm diameter. Its surface temperature is T
and the ambient temperature is T (T > T ). The wire is to be coated with a 2 mm
thick insulation. The convective heat transfer coefficient is 20 W m-2 K-1. Assume
that T and T remain unchanged. To reduce heat loss from the wire, the maximum
allowed thermal conductivity of the insulating material, in W m-1 K-1, rounded off
to two decimal places, is
(A) 0.02
(B) 0.04
(C) 0.10
(D) 0.01
Q.41 Two large parallel planar walls are maintained at 1000 K and 500 K. Parallel
radiation shields are to be installed between the two walls. Assume that the
emissivities of the walls and the shields are equal. If the melting temperature of the
shields is 900 K, the maximum number of shield(s) that can be installed between
the walls is (are)
(A) 1
(B) 0
(C) 2
(D) 3
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GATE 2022 Chemical Engineering (CH)
Q.42 Saturated steam condenses on a vertical plate maintained at a constant wall
temperature. If x is the vertical distance from the top edge of the plate, then the local
heat transfer coefficient ℎ(x) ∝ Г(x) / , where Г(x) is the local mass flow rate
of the condensate per unit plate width. The ratio of the average heat transfer
coefficient over the entire plate to the heat transfer coefficient at the bottom of the
plate is
(A) 4
(B) 4/3
(C) 3/4
(D) 3
Q.43 Match the product in Group-1 with the manufacturing process in Group-2. The
correct combination is
Group-1 Group-2
P Nitric acid I Trona process
Q Phosphoric acid II Twitchell process
R Potassium chloride III Ostwald’s process
S Stearic acid IV Haifa process
(A) P-III, Q-I, R-IV, S-II
(B) P-IV, Q-I, R-II, S-III
(C) P-III, Q-IV, R-I, S-II
(D) P-I, Q-IV, R-II, S-III
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GATE 2022 Chemical Engineering (CH)
Q.44 The directional derivative of f ( x, y, z ) 4 x 2 2 y 2 z 2 at the point (1,1,1) in the
direction of the vector v iˆ kˆ is _________ (rounded off to two decimal places).
Q.45 Consider a sphere of radius 4, centered at the origin, with outward unit normal n̂
2 xiˆ 3 yjˆ 4 zkˆ
on its surface S . The value of the surface integral nˆ dA is
S
4
___________ (rounded off to one decimal place).
Q.46 dy
The equation xy 2 2 y x 4.5 with the initial condition y( x 0) 1 is to be
dx
solved using a predictor-corrector approach. Use a predictor based on the implicit
Euler’s method and a corrector based on the trapezoidal rule of integration, each
with a full-step size of 0.5. Considering only positive values of y, the value of y at
x = 0.5 is ___________ (rounded off to three decimal places).
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GATE 2022 Chemical Engineering (CH)
Q.47
A substance at 4 °C has a thermal expansion coefficient β = = 0 K-1, an
isothermal compressibility, κ = − = 5 × 10−4 Pa-1 and a molar
volume v = 18 × 10 m3 mol-1. If s is the molar entropy, then at 4 °C, the quantity
v evaluated for the substance is __________ J mol-1 K-1 (rounded off to
the nearest integer).
Q.48 The molar excess Gibbs free energy (g ) of a liquid mixture of A and B is given by
g
= x x [C + C (x − x )]
RT
where x and x are the mole fraction of A and B, respectively, the universal gas
constant, R = 8.314 J K-1 mol-1, T is the temperature in K, and C , C are
temperature-dependent parameters. At 300 K, C = 0.45 and C = −0.018. If γ
and γ are the activity coefficients of A and B, respectively, the value of
γ
ln dx
γ
at 300 K and 1 bar is _________ (rounded off to the nearest integer).
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GATE 2022 Chemical Engineering (CH)
For a pure substance, the following data at saturated conditions are given:
Q.49
ln P (bar) T (K)
0.693 350
1.386 370
Assume that the vapor phase behaves ideally, the molar volume of the liquid is
negligible, and the latent heat of vaporization is constant over the given temperature
range. The universal gas constant, R = 8.314 J K-1 mol-1. From the above data, the
estimated latent heat of vaporization at 360 K is ____________ kJ/mol (rounded
off to one decimal place).
Q.50 Consider the process flowsheet in the figure. An irreversible liquid-phase reaction
A → B (reaction rate −r = 164 x kmol m-3 h-1) occurs in a 1 m3 continuous stirred
tank reactor (CSTR), where x is the mole fraction of A. A small amount of inert,
I, is added to the reactor. The reactor effluent is separated in a perfect splitter to
recover pure B product down the bottoms and a B-free distillate. A fraction of the
distillate is purged and the rest is recycled back to the reactor. At a particular steady
state, the product rate is 100 kmol h-1, the recycle rate is 200 kmol h-1 and the purge
rate is 10 kmol h-1. Given the above information, the inert feed rate into the process
is ____________ kmol h-1 (rounded off to two decimal places).
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GATE 2022 Chemical Engineering (CH)
Q.51 Two reservoirs located at the same altitude are connected by a straight horizontal
pipe of length 120 m and inner diameter 0.5 m, as shown in the figure. A pump
transfers the liquid of density 800 kg m-3 at a flow rate of 1 m3 s-1 from
Reservoir-1 to Reservoir-2. The liquid levels in Reservoir-1 and Reservoir-2 are
2 m and 10 m, respectively. Assume that the reservoirs’ cross-section areas are large
enough to neglect the liquid velocity at the top of the reservoirs. All minor losses
can be ignored. The acceleration due to gravity is 9.8 m s-2. If the friction factor for
the pipe-flow is 0.01, the required power of the pump is _________ kW (rounded
off to one decimal place).
Q.52 A venturi meter (venturi coefficient, C = 0.98) is connected to a pipe of inner
diameter 50 mm. Water (density 1000 kg m-3) is flowing through the pipe. The
pressure-drop measured across the venturi meter is 50 kPa. If the venturi throat
diameter is 20 mm, the estimated flow rate of water is _______ 10-3 m3 s-1
(rounded off to two decimal places).
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GATE 2022 Chemical Engineering (CH)
Q.53 In a constant-rate cake filtration operation, the collected filtrate volumes are 120 m3
and 240 m3 at 1 min and 2 min, respectively. Assume the cake resistance to be
constant and the filter medium resistance to be negligible. If the pressure-drop
across the cake is 10 kPa at 1 min, its value at 2 min is _________ kPa (rounded off
to the nearest integer).
Q.54 A cylindrical fin of diameter 24 mm is attached horizontally to a vertical planar
wall. The heat transfer rate from the fin to the surrounding air is 60% of the heat
transfer rate if the entire fin were at the wall temperature. If the fin effectiveness is
10, its length is ___________ mm (rounded off to the nearest integer).
Q.55 A single-effect evaporator with a heat transfer area of 70 m2 concentrates a salt
solution using steam. The salt solution feed rate and temperature are 10000 kg h-1
and 40 °C, respectively. The saturated steam feed rate and temperature are
7500 kg h-1 and 150 °C, respectively. The boiling temperature of the solution in the
evaporator is 80 °C. The average specific heat of the solution is 0.8 kcal kg-1 K-1.
The latent heat of vaporization is 500 kcal kg-1. If the steam-economy is 0.8, the
overall heat transfer coefficient is ________ kcal h-1 m-2 K-1 (rounded off to the
nearest integer).
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GATE 2022 Chemical Engineering (CH)
Q.56 An equimolar binary mixture is to be separated in a simple tray-distillation column.
The feed rate is 50 kmol min-1. The mole fractions of the more volatile component
in the top and bottom products are 0.90 and 0.01, respectively. The feed as well as
the reflux stream are saturated liquids. On application of the McCabe-Thiele
method, the operating line for the stripping section is obtained as
y = 1.5x − 0.005
where y and x are the mole fractions of the more volatile component in the vapor
and liquid phases, respectively. The reflux ratio is _______ (rounded off to two
decimal places).
Q.57 The dry-bulb temperature of air in a room is 30 °C. The Antoine equation for water
is given as
4000
ln P sat 12.00
T 40
sat
where T is the temperature in K and P is the saturation vapor pressure in bar.
The latent heat of vaporization of water is 2000 kJ kg-1, the humid heat is
1.0 kJ kg-1 K-1, and the molecular weights of air and water are 28 kg kmol-1 and
18 kg kmol-1, respectively. If the absolute humidity of air is Y′ kg moisture per kg
dry air, then for a wet-bulb depression of 9 °C, 1000 × Y′ = _________________
(rounded off to one decimal place).
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GATE 2022 Chemical Engineering (CH)
Q.58 K
In the block diagram shown in the figure, the transfer function G with
( s 1)
K > 0 and τ > 0. The maximum value of K below which the system remains
stable is __________ (rounded off to two decimal places).
Q.59 Consider the tank level control system shown in the figure, where the cross-section
area of the tank is A. Assume perfect flow controllers (FC). The level controller
(LC) is proportional-integral (PI). For an integral time, τ , the level controller gain,
K , is tuned for critical damping. The value of is ________ (rounded off to
the nearest integer).
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GATE 2022 Chemical Engineering (CH)
Q.60 Consider a single-input-single-output (SISO) system with the transfer function
2(s 1)
G p ( s)
1 1
s 1 s 1
2 4
where the time constants are in minutes. The system is forced by a unit step input at
time t = 0. The time at which the output response reaches the maximum is
__________ minutes (rounded off to two decimal places).
Q.61 Information for a proposed greenfield project is provided in the table. The discounted
cash flow for the fourth year is Rs ________ crores (rounded off to one decimal
place).
Fixed capital investment (excluding land) Rs 250 crores
Salvage value Rs 0
Yearly revenue from product sales Rs 120 crores
Yearly manufacturing cost (excluding
Rs 30 crores
depreciation)
Interest rate 10% compounded annually
Annual taxation rate 30%
Double declining balance*
Depreciation method
over seven years
Plant start-up 2 years after project initiation
2
* dk = BVk−1 k: years post start-up d: Depreciation amount BV: Book value
7
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GATE 2022 Chemical Engineering (CH)
Q.62 Consider the process in the figure. The liquid phase elementary reactions
A + B → P −r = k x x
P + B → S −r =k x x
S + A → 2P −r = k x x
occur in the continuous stirred tank reactor (CSTR), where x is the mole fraction
of the jth component (j = A, B, P, S) in the CSTR. It is given that k = k . All
process feed, process exit and recycle streams are pure. At steady state, the net
generation rate of the undesired product, S, in the CSTR is zero. As q = x /x
is varied at constant reactor temperature, the reactor volume is adjusted to maintain
a constant single-pass conversion of B. For a fixed product rate and 90%
conversion of B in the reactor, the value of q that minimizes the sum of the molar
flow rates of the A and S recycle streams is ________ (round off to one decimal
place).
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GATE 2022 Chemical Engineering (CH)
Q.63 An elementary irreversible liquid-phase reaction, 2A → B, is carried out under
isothermal conditions in a 1 m3 ideal plug flow reactor (PFR) as shown in the
figure. The volumetric flow rate of fresh A, v = 10 m3 h-1, and its concentration
C = 2 kmol m-3. For a recycle ratio R 0 , the conversion of A at location 2 with
respect to the fresh feed (location 1) is 50%. For R , the corresponding
conversion of A is _________% (rounded off to one decimal place).
Q.64 An elementary irreversible gas-phase reaction, A → B + C, is carried out at fixed
temperature and pressure in two separate ideal reactors: (i) a 10 m3 plug flow
reactor (PFR), (ii) a 10 m3 continuous-stirred tank reactor (CSTR). If pure A is fed
at 5 m3 h-1 to the PFR operating at 400 K, the conversion is 80%. If a mixture of
50 mol% of A and 50 mol% of an inert is fed at 5 m3 h-1 to the CSTR operating at
425 K, the conversion is 80%. The universal gas constant R = 8.314 J mol-1 K-1.
Assuming the Arrhenius rate law, the estimated activation energy is
__________kJ mol-1 (rounded off to one decimal place).
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GATE 2022 Chemical Engineering (CH)
Q.65 An elementary irreversible liquid-phase reaction, 2P ⎯ Q, where the rate
constant k = 2 L mol-1 min-1, takes place in an isothermal non-ideal reactor. The
E-curve in a tracer experiment is shown in the figure. Pure P (2 mol L-1) is fed to
the reactor. Using the segregated model, the percentage conversion of P at the exit
of the reactor is __________% (rounded off to the nearest integer).
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Q. No. Session Question Subject Key/Range Mark
Type Name (MK)
1 4 MCQ GA C 1
2 4 MCQ GA D 1
3 4 MCQ GA C 1
4 4 MCQ GA C 1
5 4 MCQ GA C 1
6 4 MCQ GA B 2
7 4 MCQ GA D 2
8 4 MCQ GA A 2
9 4 MCQ GA C 2
10 4 MCQ GA C 2
11 4 MCQ CH D 1
12 4 MCQ CH B 1
13 4 MCQ CH C 1
14 4 MCQ CH A 1
15 4 MCQ CH D 1
16 4 MCQ CH A 1
17 4 MCQ CH A 1
18 4 MCQ CH A 1
19 4 MCQ CH D 1
20 4 MCQ CH A 1
21 4 MCQ CH C 1
22 4 MCQ CH C 1
23 4 MCQ CH A 1
24 4 MCQ CH B 1
25 4 MCQ CH C 1
26 4 MCQ CH C 1
27 4 MCQ CH A 1
28 4 NAT CH 2.830 to 2.850 1
29 4 NAT CH 178.7 to 180.7 1
30 4 NAT CH 0.14 to 0.15 1
31 4 NAT CH 53.0 to 54.0 1
32 4 NAT CH 221.0 to 223.0 1
33 4 NAT CH 8.0 to 8.4 1
34 4 NAT CH 2 to 2 1
35 4 NAT CH 24.7 to 25.1 1
36 4 MCQ CH A 2
37 4 MCQ CH A 2
38 4 MCQ CH A 2
39 4 MCQ CH B 2
40 4 MCQ CH A 2
41 4 MCQ CH A 2
42 4 MCQ CH B 2
43 4 MCQ CH C 2
44 4 NAT CH 4.20 to 4.30 2
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45 4 NAT CH 191.9 to 192.1 2 46 4 NAT CH 0.860 to 0.880 2 47 4 NAT CH 0 to 0 2 48 4 NAT CH 0 to 0 2 49 4 NAT CH 36.3 to 38.3 2 50 4 NAT CH 0.95 to 1.05 2 51 4 NAT CH 87.0 to 88.0 OR 161.7 to 163.2 2 52 4 NAT CH 3.10 to 3.17 2 53 4 NAT CH 20 to 20 2 54 4 NAT CH 94 to 94 2 55 4 NAT CH 675 to 680 2 56 4 NAT CH 0.61 to 0.65 2 57 4 NAT CH 10.0 to 12.0 2 58 4 NAT CH 0.70 to 0.72 2 59 4 NAT CH -4 to -4 OR 4 to 4 2 60 4 NAT CH 0.54 to 0.56 2 61 4 NAT CH 52.0 to 54.0 2 62 4 NAT CH 3 to 3 2 63 4 NAT CH 38.0 to 38.5 2 64 4 NAT CH 47.0 to 49.0 2 65 4 NAT CH 50 to 50 2
Text of page 1
Q. No. Session Question Subject Key/Range Mark
Type Name (MK)
1 4 MCQ GA C 1
2 4 MCQ GA D 1
3 4 MCQ GA C 1
4 4 MCQ GA C 1
5 4 MCQ GA C 1
6 4 MCQ GA B 2
7 4 MCQ GA D 2
8 4 MCQ GA A 2
9 4 MCQ GA C 2
10 4 MCQ GA C 2
11 4 MCQ CH D 1
12 4 MCQ CH B 1
13 4 MCQ CH C 1
14 4 MCQ CH A 1
15 4 MCQ CH D 1
16 4 MCQ CH A 1
17 4 MCQ CH A 1
18 4 MCQ CH A 1
19 4 MCQ CH D 1
20 4 MCQ CH A 1
21 4 MCQ CH C 1
22 4 MCQ CH C 1
23 4 MCQ CH A 1
24 4 MCQ CH B 1
25 4 MCQ CH C 1
26 4 MCQ CH C 1
27 4 MCQ CH A 1
28 4 NAT CH 2.830 to 2.850 1
29 4 NAT CH 178.7 to 180.7 1
30 4 NAT CH 0.14 to 0.15 1
31 4 NAT CH 53.0 to 54.0 1
32 4 NAT CH 221.0 to 223.0 1
33 4 NAT CH 8.0 to 8.4 1
34 4 NAT CH 2 to 2 1
35 4 NAT CH 24.7 to 25.1 1
36 4 MCQ CH A 2
37 4 MCQ CH A 2
38 4 MCQ CH A 2
39 4 MCQ CH B 2
40 4 MCQ CH A 2
41 4 MCQ CH A 2
42 4 MCQ CH B 2
43 4 MCQ CH C 2
44 4 NAT CH 4.20 to 4.30 2
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45 4 NAT CH 191.9 to 192.1 2 46 4 NAT CH 0.860 to 0.880 2 47 4 NAT CH 0 to 0 2 48 4 NAT CH 0 to 0 2 49 4 NAT CH 36.3 to 38.3 2 50 4 NAT CH 0.95 to 1.05 2 51 4 NAT CH 87.0 to 88.0 OR 161.7 to 163.2 2 52 4 NAT CH 3.10 to 3.17 2 53 4 NAT CH 20 to 20 2 54 4 NAT CH 94 to 94 2 55 4 NAT CH 675 to 680 2 56 4 NAT CH 0.61 to 0.65 2 57 4 NAT CH 10.0 to 12.0 2 58 4 NAT CH 0.70 to 0.72 2 59 4 NAT CH -4 to -4 OR 4 to 4 2 60 4 NAT CH 0.54 to 0.56 2 61 4 NAT CH 52.0 to 54.0 2 62 4 NAT CH 3 to 3 2 63 4 NAT CH 38.0 to 38.5 2 64 4 NAT CH 47.0 to 49.0 2 65 4 NAT CH 50 to 50 2
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Source: GATE. Question paper published by GATE.