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1) Two cars start at the same time from the same location and go in the same direction.

The speed of the first car is 50 km/h and the speed of the second car is 60 km/h. the

number of hours it takes for the distance between the two cars to be 20 km is _______.

a) 1

b) 2

c) 3

d) 6

Ans. B

2) The search engine’s business model _________ around the fulcrum of trust.

a) Revolves

b) Plays

c) Sinks

d) Bursts

Ans. A

3) The expenditure on the project ___________ as follows: equipment Rs. 20 lakhs,

salaries Rs 12 lakhs, and contingency Rs. 3 lakhs.

a) Break down

b) Break

c) Breaks down

d) Breaks

Ans. C

4) A court is to a judge as _______ is to a teacher.

a) A student

b) a punishment

c) a syllabus

d) a school

Ans. D

5) ten friends planned to share equally the cost of buying a gift for their teacher. Where

two of them decided not to contribute, each of the other friends had to pay Rs 150 more.

The cost of the gift was Rs. _________.

a) 666 b) 3000 c) 6000 d) 12000

Ans. C



6) In a collage, there are three student clubs. Sixty students are only in the Drama club,

80 students are only in the dance club, 30 students are only in the Maths club, 40 students

are in both Drama and Dance clubs, 12 students are in both Dance and Maths clubs, 7

students are in both Drama and Maths clubs, and 2 students are in all the clubs. If 75% of

the students in the collage are not in any of these clubs, then the total number of students

in the college is _________.

a) 1000

b) 975

c) 900

d) 225

Ans. C

7) In the given diagram, teachers are represented in the triangle, researches in the

circle and administrators in the rectangle. Out of the total number of the people, the

percentage of administrators shall be in the range of ________.

a) 0 to 15

b) 16 to 30

c) 31 to 45

d) 46 to 60

Ans. C





8) The police arrested four criminals – P, Q, R and S. the criminals knew each other.

They made the following statements:

P says “Q committed the crime”

Q says “ committed the crime”

R says “I did not do it”

S says “What Q said about me is false”

Assume only one of the arrested four committed the crime and only one of the statements

made above is true. Who committed the crime?

a) P

b) R

c) S

d) Q

Ans. B

9) Three of the five students allocated to a hostel put in special requests to the warden.

Given the floor plan of the vacant rooms, select the allocation plan that will accommodate

all their requests.

Request by X : due to pollen allergy, I want to avoid a wing next to the garden.

Request by Y: I want to live as far from the washrooms as possible , since I am very

sensitive to smell.

Request by Z: I believe in Vaastu and so want to stay in the South- west wing.

The shaded rooms are already occupied. WR is washroom.

a)

b)



c)

d)

Ans. D

10) ‘ A recent High Court judgment has sough to dispel the idea of begging as a disease

which leads to its stigmatization and criminalization-and to regard it as a symptom. The

underlying disease is the failure of the state to protect citizen who fall through the social

security net’

a) Beggars are lazy people who beg because they are unwilling to work

b) Beggars are created because of the lack of social welfare schemes

c) Begging is an offence that that has to be deal with firmly

d) Begging has to be banned because if adversely affects the welfare of the state

Ans. B





TECHNICAL SECTION:

1) For a binary nonideal A-B mixture exhibiting a minimum boiling azeotrope, the

activity coefficients, yI (i= A,B), must satisfy

a) YA > 1, YE > 1

b) YA < 1, YE > 1

c) YA = 1, YE = 1

d) YA < 1, YE < 1

Ans. A

2) Producer gas is obtained by

a) Passing air through red hot coke

b) Thermal cracking of naphtha

c) Passing steam through red hot coke

d) Passing air and steam through red hot coke

Ans. D

3) The most common catalyst used for oxidation of o- xylene to phthalic anhydride is

a) V2O2

b) Pd

c) Pt

d) Ag

Ans. A

4) The correct expression for the colburn j-factor for mass transfer that relates

Sherwood number (Sh). Reynolds number (Re) and Schmidt number (Sc) is

a) 1/3

Sh

(Re)(Se)

b) 1/2

Sh

(Re) (Se)

c) 1/2 1/3

Sh

(Re) (Se)

d) Sh

(Re)(Se)

Ans. A



5) For a first order reaction in a porous spherical catalyst pellet, diffusional effects are

most likely to lower the observed rate of reaction for

a) Slow reaction in a pellet of smell diameter

b) Slow reaction in a peller of large diameter

c) Fast reaction in a pellet of small diameter

d) Fast reaction in a pellet of large diameter

Ans. D

6) In kraft process, the essential chemical reagents used in the digester are

a) Caustic soda, mercaptans and ethylene oxide

b) Caustic soda, sodium sulphide and soda ash

c) Quick lime, salt cake and dimethyl sulphide

d) Baking soda, sodium sulphode and mercaptans

Ans. B

7) A system of n homogeneous linear equations containing n unknowns will have non-

trivial solutions if and only if the coefficient matrix is

a) 1

b) -1

c) 0

d)

Ans. C

8) Consider a sealed rigid bottle containing CO2 and H2O at 10 bar ambient

temperature. Assume that the gas phase in the bottle is pure CO2 and follows the ideal gas

law. The liquid phase in the bottle contains CO2 dissolved in H2O and is an ideal solution.

The Henry’s constant at the system pressure and temperature is HCO2 = 1000 bar. The

equilibrium mole fraction of CO2 dissolved in H2O is _________ (rounded off to three decimal

places).

Ans. 0.010

9) A thermocouple senses temperature based on the

a) Nerst Effect

b) Maxwell Effect

c) Seebeck Effect

d) Peltier Effect

Ans. C



10) In the drying of non- dissolving solids at constant drying conditions, the internal

movement of moisture in the solid has a dominant effect on the drying rate during

a) The initial adjustment period only

b) The constant rate period only

c) The falling rate period only

d) Both the initial adjustment and constant rate periods

Ans. C

11) Consider the two countercurrent heat exchanger designs for heating a cold stream

from tin to tout . as shown in figure. The hot process stream is available at Tin . the inlet

stream conditions and overall heat transfer coefficients are identical in both the designs.

The heat transfer area in Design I and Design II are respectively I

HXA and II

HXA

If heat losses are neglected, and if both the designs are feasible, which of the following

statements holds true:

a) I I I II

HX HX out outA A T T

b) I I I II


c) I I I II


d) I I I II


Ans. B

12) In petroleum refining operations, the process used for converting paraffins and

naphthes to aromatics is

a) Alkylation

b) Catalytic reforming

c) Hydrocracking

d) Isomerization

Ans. B



13) For a fully- developed turbulent hydrodunamic boundary layer for flow past a flat

plate, the thickness of the boundary layer increases with distance with distance x from the

leading edge of the plate, along the free- stream flow direction, as

a) x0.5

b) x1.5

c) x0.4

d) x0.8

Ans. D

14) the desired liquid phase reaction

1k2 0.3

F 1 D ED E F r k C C

Is accompanied by an undesired side reaction 2k

0.4 1.5

F 2 D ED E F r k C C

Four isothermal reactor schemes (CSTR: ideal Continuous- Stirred Tank Reactor; PFR :

ideal Plug Flow Reactor) for processing equal molar feed rates of D and E are shown in

figure Each scheme is designed for the same conversion. The scheme that gives the most

favorable product distribution is:

Ans. C



15) Consider a cylinder (diameter D and length D), a sphere (diameter D) and a cube

(side length D). Which of the following statements concerning the sphericity (φ) of the

above objects is true.

a) sphere cylinder cube

b) sphere cylinder cube

c) sphere cylinder cube

d) sphere cylinder cube

Ans. A

16) Prandtl number signifies the ratio of

a) MomentrmDiffusivity

ThermalDiffusivity

b) MassDiffusivity

ThermalDiffusivity

c) ThermalDiffusivity

MomentrmDiffusivity

d) ThermalDiffusivity

Mass Diffusivity

Ans. A

17) Three distillation schemes for separating an equimolar, constant relative volatility

ABC mixture into nearly pure components are shown. The usual simplifying assumptions

such as constant molal overflow, negligible heat loss, ideal trays are valids. All the schemes

are designed for minimum total reboiler duty.

Given that the relative volatilities are in the ratio A 5 C; ; 8: 2 :1, the correct option that

arranges the optimally- designed schemes in ascending order of total reboiler duty is

Scheme 1



Scheme 2

A

Scheme 3

A

,

a) I, II, III

b) III, I, II

c) II, I, III

d) III, II, I

Ans. C

18) The value of the expression x

2

tan xlim is

x

a)

b) 0

c) 1

d) -1

Ans. A



19) Pool boiling equipment operating above ambient temperature is usually designed to

operate

a) Far above the critical heat flux

b) Near the critical heat flux

c) Far above the Leidenfrost point

d) Near the Leidenfrost point

Ans.

20) The product of the eigen values of the matrix 2 3

0 7

is ______(rounded off to one

decimal places)

Ans. 14.0

21) The liquid flow rate through an equal percentage control valve, when fully open, is 150

gal/min and the corresponding pressure drop is 50 psi. if the specific gravity of the liquid is

0.8, then the valve coefficient, vC in gal/(min psi 0.5 ___(rounded off to two decimal places)

Ans. 18.97





22) Consider a rigid. Perfectly insulated, container partitioned into two unequal parts by a

thin membrane ( see figure). One part contains one mole of an ideal gas at pressure Pi and

temperature Ti while the other part is evacuated. The membrane ruptures, the gas fils the

entire volume and the equilibrium pressure is / 4f iP P . If pC (molar specific heat capacity

at constant pressure). vC (molar specific heat capacity at constant volume) and R (universal

gas constant) have the same units as molar entropy, the change in molar entropy ( )f iS S

is

a) Cpln2 + Rln4

b) –Cpln2 + Rln4

c) Rln4

d) Cpln2

Ans. C

23) For a hydraulic lift with dimensions shown in figure, assuming g = 10 m/s2, the

maximum diameter Dleft ( in m) that lifts a vehicle of mass 1000 kg using a force of 100 N is

_____(rounded off to two decimal places).

Ans. 0.20



24) For a single component system, vapor (subscript g) and liquid (subscript f) coexist in

mechanical, thermal and phase equilibrium when

a) g fu u ( equality of specific internal energy)

b) g fh h ( equality of specific enthalpy)

c) g fs s ( equality of specific entropy)

d) g fg g ( equality of specific Gibbs free energy)

Ans. D

25) The combination that correctly matches the polymer in Group-I with the

polymerization reaction type in Group-II

Group –I Group-II

P) Nylon 6 I) Condensation polymerization

Q) Polypropylene II) Ring opening polymerization

R) Polyester III) Addition polymerization

a) P-II, Q-I, R-III

b) P-I, Q-III, R-II

c) P-III, Q-II, R-I

d) P-II, Q, III, R-I

Ans. D

26) A countercurrent absorption tower is designed to remove 95% of component a from an

incoming binary gas mixture using pure solvent B. the mole ratio of A in the inlet gas is

0.02. the carrier gas flow rate is 50 kmol/h. the equilibrium relations is given by Y=2Xm,

where Y and X are the mole ratios of A in the gas and liquid phases, respectively. if the

tower is operated at twice the minimum solvent flow rate, the mole ratio of A in the exit

liquid stream is_______

Ans. 0.005



27) The value of the complex number 12i (where i= 1 ) is

a) 1

(1 )2

i

b) 1

2i

c) 1

2i

d) 1

(1 )2

i

Ans. A

28) If x, y and z are directions in a Cartesian coordinate system and I, j and k are the

respective unit vectors, the directional derivative of the function 2( , , ) 3u x y z x yz at the

point (2, 0, - 4 ) in the direction ( 2 ) / 6i j k is______

Ans. 6.53

29) Stream A with heat capacity 2000 / ( )paC J kg K is cooled from 90 oC to 45 oC in a

concentric double pipe counter current heat exchanger having a heat transfer area of 8 m2

the cold stream B of specific heat capacity 1000 / ( )paC J kg K enters the exchanger at a

flow rate 1 kg/s and 45 oC. The overall heat transfer coefficient U=250 W/(m2 K). Assume

that the mean driving force is based on the arithmetic mean temperature difference, that is

, , , ,[ ]

2 2

A in A out B in B out

AMTD

T T T TT

where T1,in and T1,out refer to the temperature of

the ith stream (I = A, B) at the inlet and exit, respectively. the mass flow rate of stream A ( in

kg/s, is_____

Ans. 0.31





30) The elementary irreversible gas-phase reaction AB + C is carried out adiabatically

ion an ideal CSTR (Continuous Stirred Tank Reactor) operating at 10 atm. Pure A enters the

CSTR at a flow rate of 10 mol/s and a temperature of 450 K. assume A, B and C to be ideal

gases. The specific heat capacity at constant pressure ( )piC and heat of formation

0

iH , of component I ( I = (A, B C) are:

CPA = 30 J/(mol K) CPB = 10 J/ (mol K) CPC = 20 J/ (mol K)

0

AH = -90 kJ / mol 0

BH = - 54 kJ/ mol 0

CH = -45 kJ/mol/

The reaction rate constant k (per second) = 0.133 exp 1 1

{ ( )}450

E

R T , E = 31.4 Kj/MOL AND

UNIVERSAL GAS CONSTANT r = 0.082 L atm (mol K) = 8.314 (J/ (mol K). The shafts work

may be neglected in the analysis, and specific heat capacities do not vary with temperature.

All heats of formations are referenced to 273 K. The reactor volume ( in Liters) for 75%

conversion is _____

Ans. 89

31) A solid sphere of radius 1 cm and initial temperature of 25 oC is exposed to a gas

stream at 100 oC . For the solid sphere, the density is 104 kg/m3 and the specific heat

capacity is 500 J/(kg K.). The density of the gas is 0.6 kg/m3 and its specific heat capacity is

103 J/(kg K). the solid sphere is approximated as a lumped system (Biot number << 1) and

all specific heats are constant. If the heat transfer coefficient between the solid and gas is

50 W/(m2 K), the time (in seconds) needed for the sphere to reach 95 oC is ______

Ans. 903



32) A first-order irreversible liquid phase reaction AB (k= 0.1 min-1) is carried our under

isothermal, steady state conditions in the following reactor arrangement comprising an

ideal CSTR (Continuous-Stirred Tank Rector) and two ideal PFRs ( Plug Flow Reactors) fro

the information in the figure the volume of the CSTR (in Liters ) is______

Ans. 856

33) Consider a vessel containing steam at 180 oC. The initial steam quality is 0.5 and the

initial volume of the vessel is 1 m3. The vessel loses heat at a constant rate q under isobaric

conditions so that the quality of steam reduces to 0.1 after 10 hours. The thermodynamic

properties of water at 180 oC are (subscript g: vapor phase; subscript f: liquid phase).

Specific volume: 0.19405gv m3/kg, 0.001127fv m3/kg,

Specific internal energy: 2583.7 / ,gu kJ kg 762.08. /fu kJ kg

Specific enthalpy: 277.2. /gh kJ kg 277.2. /gh kJ kg

The rate of heat loss q ( in kJ/hour) is________

Ans. 747

34) A disk turbine is used to stir a liquid in a baffled tank. To design the agitator,

experiments are performed in a lab-scale model with a turbine diameter of 0.05 m and a

turbine impeller speed of 600 rpm. The liquid viscosity is 0.001 Pa s while the liquid

density 1000 kg/m3 the actual application has a turbine diameter of 0.5 m, and impeller

speed of 600 rpm, a negligible. If the power required in the lab-scale model is Pi and the

estimated power for the actual application is P2 then the ratoo P2/P1 is_____

a) 103 b) 104 c) 105 d) 106

Ans. C



35) Choose the option that correctly matches the step response curves on the left with the

appropriate transfer function on the right. The step input change occurs at time t = 0

a) P-III, Q-IV, R-II S-I

b) P-III, Q-I, R-IV, S-II

c) P-IV, Q-III, R- II, S-I

d) P-III, Q-II, R-IV, S-I

Ans. B

36) Carbon monoxide (CO) reacts with hydrogen sulphide (H2S) at a constant temperature

of 800 K and a constant pressure of 2 bar as:

CO + H2S 2COS H

The Gibbs free energy of the reaction 22972.3og rxn J/mol and universal gas constant R=

8.314 J/(mol K). both the reactants and products can be assumed to be ideal gases. If

initially only 4 mol of H2S and 1 mol of CO are present, the extent of the reaction ( in mol) at

equilibrium is________

Ans. 0.29



37) A centrifugal pump is used to pump water (density 1000 kg/m3)from an inlet pressure of 105 Pa to an exit pressure of 2 x 105 Pa. the exist is at an elevation of 10 m above the pump . the average velocity of the fluid is 10 m/s. the cross-sectional area of the pipes at the pump inlet and outlet is 10-3 m2 and acceleration due to gravity is g = 10 m/s2 Neglecting losses in the system , the power (in watts) delivered by the pump is ____________

Ans. 2000

38) A taxi – car is bought for Rs 10 lakhs . its salvage value is zero. The expected yearly

income after paying all expenses and applicable taxes is Rs 3 lakhs. The compound

interest rate is 9 % per annum the discount payback period (in years), is ______________

(rounded off to the next higher integer).

Ans. 5

39) For the closed loop system shown in figure, the phase margin(in degress) is ________

Ans. 45.4

40) 100 kg of a feed containing 50 wt% of a solute C is contracted with 80 kg of a solvent

containing 0.5 wt% of C in a mixer-settler unit. From this operations the resultant extract

and raffinate phase contains 40wt% and 20wt% of C, respectively .if E and R denote the

mass of the extract and raffinate phases respectively the ratio E/R is

a) 1/4

b) 1/2

c) 2/3

d) 1

Ans. C



41) Two spherical camphor particles of radii 20cm and 5cm, far away from each other, are

undergoing sublimation in a stream of air. The mass transfer coefficient is proportional to

1/ , where r(t) is the radius of the sphere at time t. Assume that the partial pressure of

camphor far away from the surface of the particle is zero. Also, assume quasi-steady state,

identical ambient conditions, and negligible heat effects. If t1 and t2 are the times required

for complete sublimation of the 20cm and 5cm camphor particles, respectively, the ratio

t1/t2 is______(rounded off to one decimal place).

Ans. 8.0

42) A fractionators recovers 95 mol n-propane as the distillate from an equimolar

mixture of n-propane and n-butane. The condensate is a saturated liquid at 55 C. The

Antoine equation is of the form, In (Psat [in bar])= A-

[ ] , and the constants are

provided below:

A B C n-propane 9.1058 1872.46 -25.16 n-butane 9.0580 2154.90 -34.42 Assuming Raoult’s law, the condenser pressure (in bar) is _______(rounded off to one

decimal place).

Ans. 17.9

43) Consider the reactor-separator-recycle process operating under steady state

conditions as shown in fig. The reactor is an ideal Continuous-Stirred Tank Reactor (CSTR),

where the reaction A+B C occurs. Assume that there is no impurity in the product and

recycle streams. Other relevant information are provided in the fig. The mole fraction of

B(xB)in the reactor that minimizes the recycle rate is__________(rounded off to two decimal

places).

Ans.

44) For a given binary system at constant at constant temperature and pressure, the molar

volume (in m3/mol) is given by 30 20 (15 7 )A B A B A Bv x x x x x x where xA and xB are the

mole fractions of components A and B respectively. the volume change of mixing maxv in

(in m3/mol) at x = 0.5 is__________

Ans. 1

45) A 20 cm diameter cylindrical solid peller of a nuclear fuel with density 6000 kg/m3 and

conductivity of 300 W/(m K) generates heat by nuclear fission at a spatially uniform rate of

104 W/kg. The heat from the fuel pellet is transferred to the surrounding coolant by



convection such that the pellet wall temperature remains constant at 300 0C . Neglecting

the axial and azimuthal dependence, the maximum temperature ( in 0C ) in the pellet at

steady state is___________

Ans. 800



46) A binary mixture with A and B is to be separated in a distillation column to obtain 95

mol% A as the top product. The binary mixture has a constant relative volatility 2AB .

The column feed is a saturated liquid containing 50 mol% A . under that usual simplifying

assumptions such as constant molar overflow, negligible heat loss ideal trays the minimum

reflux ratio for this separating is__________

Ans. 1.7

47) An incompressible Newtonian fluid flow in pipe diameter Di at volumetric flow rate Q.

Fluid with same properties flows in another pipe of diameter D2 = Di /2 at the same flow

rate Q. The transition length required for achieving fully- developed flow is iI for the tube

of diameter Di while it is l2 for the tube of diameter D2 Assuming steady laminar flow in

both case the ratio 1 2/l l is

a) 1/4

b) 1

c) 2

d) 4

Ans. B

48) Two unbiased dice are thrown. Each dice can show any number between 1 and 6. The

probability that the sum of the outcomes

Ans. 0.25

49) The Newton-Raphson method is used to determine the root of the equation f(x)=e-x – x.

If the initial guess for the root is 0, the estimate of the root after two iterations is

_______(rounded off to three decimal places).

Ans. 0.566

50) The solution of the ordinary differential equation

+ 3y=1, subject to the initial

condition y=1 at x=0, is

a)

(1+2e-x/3)

b)

(5-2e-x/3)



c)

(1+2e-3x)

d)

(1+2e-3x)

Ans. D

51) The combination that correctly matches the process in Group-I with the entries in

Group -2

Group -1 Group -2 P) Wulff process I) Sulfur mining Q) Sulfite Process II) Soda ash production R) Solvay process III) Acetylene production S) Frasch process IV) Pulp production

a) P-II,Q-IV,R-III,S-I

b) P-III,Q-IV,R-II,S-I

c) P-IV,Q-I,R-II,S-III

d) P-II,Q-I,R-IV,S-III

Ans. B

52) The elementary liquid –phase irreversible reactions 1 1

1 20.4min 0.1minK K

A B C

Take place in an isothermal ideal CSTR (continues- stirred tank Reactor). Pure A is

fed to the reactor at a concentration of 2 mol/Liter . for the residence time that

maximizes the exit concentration of B ,the percentage yield of B, defined as

100net formation rateof B

consumption rateof A

is __________________.

Ans. 67

53) Consider two competing equipment A and B for a compound interest rate of 10% per

annum in order for equipment B to be the economically cheaper option, its minimum

life (in years) is ___________

Equipment Capital Cost (Rs)

Yearly operating Cost(Rs)

Equipment life (years)

A 80,000 20,000 4 B 1,60,000 15,000 ?

Ans. 8



54) The elementary irreversible, liquid-phase parallel reactions 2A D and 2A U , take

place in an isothermal non-ideal reactor. The C-curve measured in a tracer experiment

is shown in the figure, where C(t) is the concentration of the tracer in g/m3 at the

reactor exit at time t(in min).

The rate constants are K1=0.2 Liter/(mol min) and K2=0.3 Liter/(mol min).pure A is fed to

the reactor at a concentration of 2 mol/liter. Using the segregated model, the percentage

conversation in the reactor is ________________-

Ans. 65

55) consider two non-interacting tank in series as shown in fig. water enters TANK 1at q

cm3/s and drains down to TANK 2 by gravity at a rate 3

1 ( / )k h cm s similarly water drains

from TANK 2 by gravity at a ratio of 3

2 ( / ).k h cm s where h1 and h2 represent levels of

TANK 1 and TANK 2, respectively (see figure). Drain value constant k =4 cm2.5/s and cross

sectional areas of the two tanks are A1=A2=28 cm2

At steady state operation, the water inlet flow rate is qxx=16 cm3/s. the transfer function

relating the deviation variable 2h

(cm) to flow rate 3( / )q cm s

is

a) 2

2

(56 1)s

b) 2

2

(62 1)s

c) 2

2

(36 1)s

d) 2

2

(49 1)s

Ans. A





Detailed Solutions

Technical Section

Solution: 2)

Producer Gas is made when partial combustion of carbonaceous Substance usually coal or cake takes

place in an atmosphere of air and steam.

According to given options.

When air & steam both passes through red hot coke.

D) is the correct answer

Solution: 3)

Catalyst used in the production of Phthalic Anhydride from 0 – xylene is V2O5

A)

is the correct answer



Solution: 4)

The correct expression used in the J-Factor analogy that relates the Sherwood number, Reynold’s

Number and Schmidt Number is______

1

3M

f SherwoodJ

2 Re ynolds.Schmidt

13

M

f SherwoodJ

2 Re ynolds.Pr andtl

A)

is the correct answer

Solution: 5)

Pore diffusion will control the process only and only when pore diffusion resistence will be high.

So for large pore diffusion resistance, Thiele modulus, 4

Thus, √

Hence, fast surface run & large pore size will be required.


Solution: 6)

In the Kraft process, for the making of pulp, the chemical reagents used is white liquor, water and

woodchips.

50 Parts of water Caustic soda Sodium sulphide

25 Parts of white liquor (NaoH + Na2S)

25 Parts of woodchips (obtained from chipper bin)

White liquor essentially is NaOH but Na2S is added so that later on bleaching becomes easy.

B) is the correct answer

Solution: 8)

Answer:- According to Henry’s law

Pa = H.xA



For the pure Co2, particle pressure will be same as the pressure of Co2 in gas phase, which is 10

bar.

10=1000. XA

XA =

= 0.01

Solution: 9)

A Thermocouple senses temperature based on

a) Nernest Effect: It is observed when a sample allowing electrical conduction is subjected to a

magnetic field.

Hence it cannot be the answer

b) Peltier Effect: It is observed when electric current passes through or across a junction

between two dissimilar conductors.

Hence it cannot be the answer.

c) Maxwell Effect: It is a characteristic property of liquids related to birefringence

Hence It cannot be the answer.

d) Seeback Effect: Also known as thermoelectric effect that states an emf is generated

between two ends when they are at different temperatures.

C) is the Right Answer.

Solution: 11)

out in in out out in in out

1 X 1 Xout in out in

in out in out

T ' t T t T" t T tQ UA ' UA"

T ' t T" tln ln

T t T t

inT and outt are same

out out in in out out in in

1 X 1 Xout in out in

in out in out

T ' t T t T" t T tQ UA ' UA"

T ' t T" tln ln

T t T t



This is possible only if 1 X 1 XA" A" and out outT' T"


Solution: 12)

Process for converting Napthenes and paraffins to Aromatics is Catalytic Reforming.


Solution: 13)

for Turbulent boundary layer

0.2 0.2 0.2

1 0.2

0.8

0.385

Re Rex x

x x

x x

x

x


Solution: 15)

Sphere=D

Cube=D

Cylinder= 2=D

sphere = 1

cube= 0.806

Cylinder =0.873

A) is the correct answer



Solution: 17)

Relative volatilities of A.B. & C = 8, 2, 1 Arrange the given options into ascending order of

“Reboiler Duty”

Scheme 1

Scheme 2

A

Scheme 3

A

,



In Scheme 1

Reboiler Duty (Scheme) is being utilized for the vaporization of B & C in the first column and C

from the second colum.

In Scheme 2

Reboiler Duty is being utilized for the vaporization of B & C from the first and B from the second

column.

In Scheme 3

Reboiler Duty is being utilized for the partial valorization of B & C from the first and B and C

from the second and third column.

Ascending order for Increase in reboiler duty is Scheme 2 < Scheme 1 < Scheme 3

Answer - C

Solution: 18)

2

tan

x

xLim

x

R.H.L

0

tan2

2

h

h

Lim

h

0

coth

2

hLim

h

0

cot h

2

hLim

h

cot 0

2



L.H.L

2

0

0

0

tan

tan2

( )2

coth

2

cot

2

cot 0

2

x

h

h

h

xLim

x

h

Lim

h

Lim

h

hLim

h

R.L.S = L.H.S = Ans

Solution: 20)

7 6

0 2A

14 0 14A

Product of Eigen values = Determinant of Matrix =14

Ans. 14

Solution: 21)

Liquid Flow Rate |fully opened value= 150 gal/min

Pressure drop = 20 Psi



Specific Gravity of the liquid = 0.8

Valve coefficient Cv= ?

We know

Q = Cv VP

G

Cv = ?

Cv = 150

18.9750

0.8V

q

P

G

Answer = 18.97

Solution: 22)

/ 4

f f

f c p n n

i i

in

i

T ps s c R

T p

pR

p

Tf = Ti, free expansion

= 4nR

C) is the correction answer

Solution: 23)

We have

1000 kg, g = 10 m/s100 N2



By pascal’s law

1 2

1 2

1 2

2 2

1

2

1 1

100 1000 10

(2)4 4

, 0.04 0.2

P P

F F

A A

d

Thus d d m

Solution: 24)

In Vapor-Liquid equilibrium system, where thermal, mechanical and chemical equilibrium exist, means

thermodynamic equilibrium exist, the criteria of thermodynamic equilibrium says,

(molar cuibbs energy)Liquid phase = (molar cuibbs energy)Vapor phase

D) is the correct answer.

Solution: 25)

Nylon -6 belongs to Ring Opening Polymerization, Polypropylene belongs to Addition and Polyester

belongs to Condensation


Solution: 26)

For 95% removal of solute in absorption using solvent flow rate twice of the minimum solvent flow rate.

Exit composition is equal to______.

Equilibrium relation is y = 2X



2 1

2 1

y y 0.02 0.001m 1.9

x x 0.01 0

Also minLsm

Gs (slope of operating line)

minmin

Ls1.9 Ls 95

50 Gs 50 given

Ls operating = 2 Lsmin (Given) = 2 x 95 =190

Lsoperating

Gs=

1903.8

50

1

1

0.02 0.001 Lsoperatingm 3.8

X 0 Gs

1X 0.005

Ans= 0.005



Solution: 27)

Find the value of 1

2i

We know

/2

1

2( 1/2) 42

cos sin

cos sin2 2

i

i

ii

e i

and

e i i

whichmeans

i e e

1

2 4

1

2

1

2

cos sin4 4

1 1 11

2 2 2

(1 )

2

i

i e i

i i i

ii

A)

Solution: 28)

2( , , ) 3u x y z x xy

u u uu i j k

x y z

= 2 ( 3 ) ( 3 )x i z j y k

(2,0, 4) 4 12 0u i j k

6

i j ka



Directional Derivate = .u a

= 4 12 16

6.5326 6

Solution: 29)

A

45 0C

x

2

2000 /

1000 /

250 /

?

1 /

h

c

h

c

c J kg k

c J kg k

U w m k

m

m kg s

90 45 45 90( )

2 2 2

AMTD

x xT

( ) 2000 45 1 1000 ( 45) AMTD hQ UA T m x

90250 8 90000 1000( 45)

2

h

xm x

On solving above equations, we get:

0.31 / hm kg s

Solution: 30)

10AO

Pure A

F mol



To =450K

CPA = 30

10 20, ,

. .PB Pc

J J JC C

mol k mol mol K

= (-45) + (-54) – (-90)

9 /o

rxnH kj mol

K = 0.133 exp 1 1

450

E

R T

31.4 /

8.314 / .

E kJ mol

R J mol K

XA = 0.75 Vm ( ) = ?

FA= FAo ( 1-XA) = 2.5 mol

FB = FBO + . 7.5AO

bF XA mol

a

FC = FCO + . 7.5AO A

cF X mol

a

Energy in – Energy out = Energy due to reaction

1 2 2 0( ) ( )AO PA B PB C PC A PAF C T T F C F C F C T T 0.FAO XA H rxn

210 30 (450 273) [2.5 30 7.5 10 7.5 20] ( 273)T = 7.5 7.5 ( - 9000 )

253100 [300]( 273) 67500T

2

2

53100 67500 300( 273)

675

T

T K

Solution: 31)

We know that



4

3

ln

95 100 50ln

125 10010 500

3 100

2.708 3 10

902.68sec

i

T T ht

T T PLc

t

X XX

X t

t onds

Ans. 903 seconds rounded off to the nearest integer.

Solution: 32)

Here it is given for 1st order reaction,

K = 0.1 min-1

PFR in series can be replaced by single PFR of same equivalent volume

Thus, for PFR line

1

,2 ( )AO AO

CA CACA AOP A

nC C

O A CA A

d CV d C

V r k k C

100 1 1

,2 0.1 0.5

,2 14.427 / min

n

o

o

V

V

There for ,1 ,2 100 14.427Vo Vo Vo

,1 85.573Vo

For MFR, ,1

AO A AO A

A

C C C CVm

Vo rA k C

,1 85.573.( ) (1 0.5)

0.1 0.5

855.73

AO A

A

VoVm C C

k C

Vm

Solution: 33)



We have

(1 )

1 .5 .19405 .5 .001127

10.24711

g fV m xv x v

m

m kg of mixture

i.e 5.123555 kg of steam and

5.123555 kg of saturated water

Since total volume of 1 m3 remains constant

1 2 2 1 1 2

2 2 1 1

2 1 2 1

2 1

(1 ) u (1 )

( ) ( )

( )( )

(0.1 0.5)(2583.7 762.08) / 10

g f g f

g f

g f

q u u w

x u x x u x u

u x x x x u

x x u u

kJ kg in hrs

Total heat transfer = -728.648 kJ/kg , -ve sign indicates that heat is lost to the surroundings

728.648 10.24711

10

746.65 /

747 / .

Heat lost per hr

kJ hr

kJ hr rounded off to thenearest integer

Solution: 34)

After checking Reynolds no. it is coming out to be 22500 which is above 1000, hence the operating flow

regime is Turbulent. And For Turbulent flow regime,

Power Number = 3 5

P

cN D

180 oC

1 m3



1 2

3 5 3 5

1 1 2 2

5 3

2 2 2

1 1 1

2 2

1 1

5 3

2

1

52

1

0.5 , 6000

0.05 , 600

0.5 600

0.05 600

10

P P

N D N D

P D N

P D N

D m N rpm

D m N rpm

P

P

P

P

Solution: 35)

Match the given response functions with the transfer function.

P)

It looks like a first order system with a Transfer function of p1

p1

k

1 S

R)



It looks like an inverse response for which 1 1

2 2

k1

k

Q)

Response is going to be unbounded and correct option for this is

1

1

k S 1

S S 1

Also by applying final value theorem, it can be validated.

Value = t s oLim f t Lim f s

d)

It matches with the last option remaining and can be matched by taking the inverse Laplace of the

transfer function.


Solution: 36)

T=800 K

P=2 bar



CO +H2S COS + H2

0 22972.3 /

8.314 /

G J mol

R J mol

wkt, 0

n

GK

RT

thus, 22972.3 /

8.314 / 800n

J molK

J mol K

K = 0.03162

For ideal gas mixture & standard state to be at 1 bar,

K = Ka = Kp = 0.03612

We know that

Kp = Ky . Pv

Here,

Yco = 2 cos

1, ,

5 5 5Hy y

yH2S = 4

05

v

putting values, 0

55 0.03160 (2)

1 4

5 5

0.2889

Solution: 37)

We have



(2)

2 2

1 1 2 21 2

5 5

3 3

2 2

10 2 1010

10 10 10 10

pump

Pump

P V P Vy H y

g g g g

H

(Pump)

20 10 10 20

. .

Pump

Pump Pump

H m

Power WQH g Q H

3 2 3

2

10 10 10 / sec

P 1000 10 10 20

2000

Pump

Q AV m

W

Solution: 38)

payback time is defined as the time period at which the investment can be easily (fully) recovered with

the help of cash flow (profit)

1 2

3 3 310 ........

(1 ) (1 ) (1 )n

L L LLakhs

i i i

As interest Rate is given, time value of money concept is used.



(1 ) 1

(1 )3 (1 ) 1

10(1 )

Pr

3 1.12 110

0.12 1.12

n

n

n

n

n

n

R iP

i iL i

Lakhs wherei i

P esentValue

R uniform periodic payments

LLakhs

0.4(1.12 ) 1.12 1n n

1 0.6(1.12)n

1 1(1.12) ln(1.12)

0.6 0.6

n n lm

1

0.64.507 5

(1.12)

Ln

n yearsLn

Solution: 39)

Find the phase margin for the given block diagram.

Step 1. Find the open loop transfer function.

GOLTF =

Step 2. Identify the system involved in the diagram. One is dead time system with td = 0.1 other

is first order system with p =0.5

Step 3. Finding the phase margin.

180 PM Where is the value of phase at gain crossover frequency.

At Gain Cross over frequency

AR=1

AR of given system = 5 × 1 ×

√

Putting AR=1, w=9.7979 rad/time

= -td w ×

+ tan-1 (-w p )

Phase angle for phase angle for first

Dead time system order system

Putting w=wcog = 9.7979



= -56.16156 - 78.46297 = -134.6245

180 PM = 180 - 134.6245

PM = 45.4

Solution: 40)

Fxf + Sys = RxR + EyE

50+0.4=0.2+ 0.4E

Also

F + S = R + E

R + E = 180

R = 180-E

Equation (i) can be written as

50.4 = 0.2(180-E)+ 0.4E

50.4= 36-0.2E + 0.4E

14.4= 0.2E

E=72 and R= 180-E = 180

=

=

Solution: 41)

Corresponding radii of spherical camphor particles are 20 cm and 5 cm.

Mass transfer coefficient 1

( )r t

‘t1’ and ‘t2’ are the times required for the complete sublimation then t1/t2 = ?

We know that, in the case of spherical naphthalene ball in air, flux

(NA)|r = r1 = 1 2

1

AB A A

BLM

P D P P

RT r P

Also, NA = KG PA



Where KG = 1

AB

BLM

P D

RT r P

Also, time taken for the complete Evaporation of naphthalene Ball

t = 2

1

2

BLM

A AB A

r RT P

M P D P

which means

t= 1

1

1

2 |A r r

r

M NA

t = 1

1

1

r

r

t r13/2

3/2

3/21 1

2 2

1 2

1

2

4 8

8

8

t r

t r

t t

t

t

Solution: 44)

We know that, volume change of mixing,

1 1 2 2

v

( v v )

i iV V x

V V x x

Molar volumes, will be

For component (1), 1

3

1 1 30m /molV x

For component (2), 3

2 2 1 20m /molV x

Thus, 21 2 1 1 2[30 20 (15 7 )]V x x x x x x 1 2(30 20 )x x



1 2 1 2(15 7 )V x x x x

1 20.5, 0.5at x x

1 0.5 0.5 0.5 (15 0.5 7 0.5)xV

3

1 0.5 1x

mV

mol

Solution: 45)

We know that

1 d dT Qr 0

r dr dr r

d dT Qr r 0

dr dr r

Integrating, 2dT Qr

r Gdr 2r

When r = 0, G = 0

dT Qr0

dr 2r _______(i)

Integrating again 2

2

QrT C

4r

When

21

2

Q Rr R,T Tw;Tw C

4R

1 2 21Q r R

T Tw Q4R 4R 4R

1 2 2

2

Q R rT Tw 1

4R R

_______(ii)



For max temp, dT

0dr

From (i) r = 0

In equation (ii)

1 2Q RT Tw

4R

Q is Heat generated/volume

2

4

3

.1wT 300 10 6000

m 4 300

= 300 + 500 = 0800 C

Solution: 46)

Find the value of minimum reflux ratio when the feed given is saturated liquid and equimolar.

Distillate Mole fraction is given as 0.95 Relative Volatility is 2.

In the condition of minimum reflux rectifying line, Equilibrium curve and feed line intersects at a

point.

Equilibrium Curve is given by y=

As on the feed line, x-coordinate is given as 0.5.

y-coordinate can be calculated from equilibrium curve as both intersects.

Y=

=

=

=

Now, Rectifying Line one end is (0.95, 0.95)and other point is (0.5,

).

Slope=

=

= Rmin = 1.7



Solution: 47)

We have

12

1 2 1 2

1 2 1 2

2

22 1

1 1 1 1 1 1 1

222 2 2 2 2 2 2

2

1 2

1

2

,2

min

0.006Re

Re.

.

4.

4

1

Q Q Q P P P

DD D D

l Enhancelength

for fully developed la ar flow

l

d

l d

vdl d

l vd

dl V d V V A Q

l V d V V A Qd

Q Q Q

l

l

B) is the correct answer.

Solution: 48)

We know when two dice are thrown, minimum possible sum is 2 and Maximum possible sum is 12.

4, 8, 12 are divisible by 4.



Number of favorable cases for getting the sum 4

(1, 3), (2, 2), (3, 1)

Number of favorable cases for getting the sum 8

(2,6), (3,5), (4,4), (5,3), (6,2)

Number of favorable cases for getting the sum 12.

(6, 6)

Total number of favorable cases = 9

Probability of getting the sum divisible by 4 = Number of favorablecases

Total number of cases

= 9 3 1

0.2536 12 4

Solution:49)

( ) xf x e x

0 0( )x Given

01 1 '

0

0

0

( )

( )

( 0 1 10

( 1) 1 1 1 2

f xx x Newton Rapson Method

f x

e

e

12 1 '

0

1/2

1/2

( )

( )

( 1/ 2 1 0.6065 0.51/ 2

( 1) 1 2 0.6065 1

f xx x

f x

e

e

0.10650.5 0.5 0.06629

1.6065

0.56629

After 2nd iteration, value of x is 0.5663



Solution: 50)

(1 3 ) (0) 1

1 3

dyy y

dx

dydx

y

Integrating both sides

1

1

1 1

3

3

2 2

3

2

3

2

22 2

3

1 3

3

1 3 3 3

1 3 3 [ 3 ]

1 3 ,

1 3 , [ ]

1 3

10

3

1

1 (1)1 3 1 2

3

1 2

3

cx

cx

x

x

x

Ln yx c

Ln y x c

Ln y x c let c c

y e e

y e c let c e

c e y

c ey put x

y

cc c

ey


Solution: 51)

Match the column

Sulfite process is used to make pulp which in turn is used to make white paper.

Solvay process is the oldest process to make Soda Ash commercially.

Frasch process is used to produce Sulphur from sulphur ore which in turn is used to make Sulphuric acid.




Solution: 52)

For First order Rxns, in MFR

For CB max, max

1 1

1. 2 0.4 0.1

k k

max 5min

Thus, for A ( ) ,

o oCA CA CA CA

rA K CA

2 25

0.4 3

CA molCA

CA

For ‘B’ 0

1 2A

CB CB CB

rB k C k CB

5 0.8892

0.4 0.13

CB molCB

CB

Hence, % yield of ‘B’ ' '

100' '

molesof B formeds

total molesof A reacted

= 100o

NB NBo

NA NA

100CB

CAo CA

YB/A = 0.889

100 66.67% 672 0.667

Solution: 53)

Capitalized cost factor = (1 )

[(1 ) 1]

n

n

i

i



The net present worth of yearly operating cost R is (1 ) 1

(1 )

n

n

iR

i i

If we convert it into capitalized cost by multiplying with capitalized cost factor, we get R

i

For equipment A: 80000 + 4

80000 20000452376.6

(1 0.1) 1 0.10

For equipment B: 160000 + 160000 15000 160000

310000(1 0.1) 1 0.10 (1.1) 1n n

For B. to be economical cheaper, n = 8 year

Solution: 54)

c (t)

5

0 6t

What will be the mean conversion using saggregation model?

Hence,

22 2

1 1 22 ( )A AA

rA k k k kCC C

Hence for 2nd order Rxn,



0

( 1 2)

1 ( 1 2)

oA

k k CA tX

k k CA t

0

0

0 0

1 )

. 1 ) 1 ): 1 )

1 ) 1 )

A A

A

A

X X E t dt

X c t dt c tX E t

c t c t dt

61 2 0

01 2 0

6

0

( )

1 (( )

1 )

AA

A

A

k k C tX

k k C t

C t dt

1 61 2 1 2

0 11 2 0 1 2 0

6

0

( ) 1 ) ( ) 1 )

1 ( ) 1 ( )

1 )

AA A

A

k k C t dt k k C t dtX

k k C t k k C t

C t dt

1 6

0 1

6

0

(0.5) 2 ( ) 0.5 2 ( )

1 0.5 2 1 0.5 2

1 )A

A

tc t dt t c t dt

t t

XC t dt

1 6

0 1

6

0

( ) (( )

1 1

( )A

A

tc t dt t c t dt

t tXC t dt

Here,

C 1t) = 5t for o < t <1

C1t) = (6 – t ) for 1 < t < 6

& 6

0

11 ) 15 ( : 6 5)

2c t dt Area

1 6

0 1

5 (6 )

1 10.6464

15

A

t t dt t t dt

t tX

Thus, % 64.64 65 AX



Solution: 55)

For Non-Interacting systems

According to the given data, A1 = A2 = 28 cm2

Steady state value of in let flow rate = 16 cm3/sec

Also, ssFo or ssFi =ss1ss 1k h 16 k h

k = 4 (Given) 1ssh 16cm

We also know

1R or

SS

ss1

1

sso

12 h1 2 16kR 2

k 42 hiF h

2 1 2

i ii

h s F s h s

F sF s F s

2

1 1 2 2

R1

A R S 1 A R S 1

Similarly the value of 2R is calculated.

As iss 1ss 2ssF F F 16

2

2i

h s 1 2 2

28 2 S 1 28 2 S 1F s 56s 1

A) Is the correct answer



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