GATE Solved Question Papers for Chemical Engineering [CH] by AglaSem.Com

SOLVED PAPERS

GATE

CHEMICAL ENGINEERING (CH)

CONTENTS

• Introduction

•

Question Paper Pattern

•

Design of Questions

•

Marking Scheme

•

Syllabus

• Previous Year Solved Papers

o

Solved Question Paper 2014

o

Answer Key 2014

o

Solved Question Paper 2013

o

Answer Key 2013

o

Solved Question Paper 2012

o

Answer Key 2012

The Graduate Aptitude Test in Engineering (GATE) is the all India level examination

conducted by the Indian Institute of Science and seven Indian Institutes of Technology

(IITs).

A crucial part of GATE preparation is to solve and practice using previous year GATE

papers. Solving previous year GATE papers help the candidate in understanding the exam

pattern, knowing the level of difficulty of questions, and analyzing preparation.

While attempting to solve any previous year GATE paper, it is advisable that it is done in a

simulated test environment. This means, that the candidate sets a timer to countdown to

test time, makes sure there is no other distraction, and then sits down to take the test as if

he / she is in the exam hall. After attempting the paper, check how many questions you

could get right in the first attempt. Analyse the strong and weak areas of preparation, and

accordingly devise a study schedule or revision pattern. After going through those areas

where in the first attempt could not do well, try the next paper.

Almost all of the engineering colleges in India take admission in M.Tech courses on the

basis of GATE scores. Apart from that, PSUs also recruit students directly on this basis.

To score high in this elite examination is tough, but quite achievable.

Question Paper Pattern

In all the papers, there will be a total of 65 questions carrying 100 marks, out of which 10

questions carrying a total of 15 marks are in General Aptitude (GA).

In the papers bearing the codes AE, AG, BT, CE, CH, CS, EC, EE, IN, ME, MN, MT, PI, TF and

XE, the Engineering Mathematics will carry around 13% of the total marks, the General

Aptitude section will carry 15% of the total marks and the remaining percentage of the

total marks is devoted to the subject of the paper.

In the papers bearing the codes AR, CY, EY, GG, MA, PH and XL, the General Aptitude

section will carry 15% of the total marks and the remaining 85% of the total marks is

devoted to the subject of the paper.

GATE would contain questions of two different types in various papers:

(i) Multiple Choice Questions (MCQ) carrying 1 or 2 marks each in all papers and

sections. These questions are objective in nature, and each will have a choice of four

answers, out of which the candidate has to mark the correct answer(s).

(ii) Numerical Answer Questions of 1 or 2 marks each in all papers and sections. For

these questions the answer is a real number, to be entered by the candidate using the

virtual keypad. No choices will be shown for this type of questions.

The questions in a paper may be designed to test the following abilities:

(i) Recall: These are based on facts, principles, formulae or laws of the discipline of the

paper. The candidate is expected to be able to obtain the answer either from his/her

memory of the subject or at most from a one-line computation.

(ii) Comprehension: These questions will test the candidate's understanding of the

basics of his/her field, by requiring him/her to draw simple conclusions from fundamental

ideas.

(iii) Application: In these questions, the candidate is expected to apply his/her

knowledge either through computation or by logical reasoning.

(iv) Analysis and Synthesis: In these questions, the candidate is presented with data,

diagrams, images etc. that require analysis before a question can be answered. A Synthesis

question might require the candidate to compare two or more pieces of information.

Questions in this category could, for example, involve candidates in recognising unstated

assumptions, or separating useful information from irrelevant information.

Marking Scheme

For 1-mark multiple-choice questions, 1/3 marks will be deducted for a wrong answer.

Likewise, for2-marks multiple-choice questions, 2/3 marks will be deducted for a wrong

answer. There is no negative marking for numerical answer type questions.

General Aptitude (GA) Questions

In all papers, GA questions carry a total of 15 marks. The GA section includes 5 questions

carrying 1 mark each (sub-total 5 marks) and 5 questions carrying 2 marks each (sub-total

10 marks).

Question Papers other than GG, XE and XL

These papers would contain 25 questions carrying 1 mark each (sub-total 25 marks) and

30 questions carrying 2 marks each (sub-total 60 marks). The question paper will consist of

questions of multiple choice and numerical answer type. For numerical answer questions,

choices will not be given. Candidates have to enter the answer (which will be a real

number, signed or unsigned, e.g. 25.06, -25.06, 25, -25 etc.) using a virtual keypad. An

appropriate range will be considered while evaluating the numerical answer type

questions so that the candidate is not penalized due to the usual round-off errors.

GG (Geology and Geophysics) Paper

Apart from the General Aptitude (GA) section, the GG question paper consists of two parts:

Part A and Part B. Part A is common for all candidates. Part B contains two sections: Section

1 (Geology) and Section 2 (Geo-physics). Candidates will have to attempt questions in Part

A and either Section 1 or Section 2 in Part B.

Part A consists of 25 multiple-choice questions carrying 1-mark each (sub-total 25 marks

and some of these may be numerical answer type questions). Each section in Part B

(Section 1 and Section 2) consists of 30 multiple choice questions carrying 2 marks each

(sub-total 60 marks and some of these may be numerical answer type questions).

contains 11 questions carrying a total of 15 marks: 7 questions carrying 1 mark each

(sub-total 7 marks), and 4 questions carrying 2 marks each (sub-(sub-total 8 marks). Some questions

may be of numerical answer type questions.

Each of the other sections of the XE paper (Sections B through G) contains 22 questions

carrying a total of 35 marks: 9 questions carrying 1 mark each (sub-total 9 marks) and 13

questions carrying 2 marks each (sub-total 26 marks). Some questions may be of

numerical answer type.

XL Paper (Life Sciences)

In XL paper, Chemistry section (Section H) is compulsory. This section contains 15

questions carrying a total of 25 marks: 5 questions carrying 1 mark each (sub-total 5 marks)

and 10 questions carrying 2-marks each (sub-total 20 marks). Some questions may be of

numerical answer type.

Each of the other sections of the XL paper (Sections I through M) contains 20 questions

carrying a total of 30 marks: 10 questions carrying 1 mark each (sub-total 10 marks) and 10

questions carrying 2 marks each (sub-total 20 marks). Some questions may be of

numerical answer type.

Note on Negative Marking for Wrong Answers

For a wrong answer chosen for the multiple choice questions, there would be negative

marking. For1-mark multiple choice questions, 1/3 mark will be deducted for a wrong

answer. Likewise, for 2-mark multiple choice questions, 2/3 mark will be deducted for a

wrong answer. However, there is no negative marking for a wrong answer in numerical

answer type questions.

Syllabus for General Aptitude (GA)

Verbal Ability: English grammar, sentence completion, verbal analogies, word groups,

instructions, critical reasoning and verbal deduction.

Numerical Ability: Numerical computation, numerical estimation, numerical reasoning

and data interpretation.

Syllabus for Chemical Engineering (CH)

ENGINEERING MATHEMATICS

Linear Algebra: Matrix algebra, Systems of linear equations, Eigen values and

eigenvectors.

Calculus: Functions of single variable, Limit, continuity and differentiability, Mean value

theorems, Evaluation of definite and improper integrals, Partial derivatives, Total

derivative, Maxima and minima, Gradient, Divergence and Curl, Vector identities,

Directional derivatives, Line, Surface and Volume integrals, Stokes, Gauss and Green’s

theorems.

Differential equations: First order equations (linear and nonlinear), Higher order linear

differential equations with constant coefficients, Cauchy’s and Euler’s equations, Initial

and boundary value problems, Laplace transforms, Solutions of one dimensional heat

and wave equations and Laplace equation.

Complex variables: Analytic functions, Cauchy’s integral theorem, Taylor and Laurent

series, Residue theorem.

Probability and Statistics: Definitions of probability and sampling theorems,

Conditional probability, Mean, median, mode and standard deviation, Random

variables, Poisson, Normal and Binomial distributions.

Numerical Methods: Numerical solutions of linear and non-linear algebraic equations

Integration by trapezoidal and Simpson’s rule, single and multi-step methods for

differential equations.

CHEMICAL ENGINEERING

Process Calculations and Thermodynamics: Laws of conservation of mass and

energy; use of tie components; recycle, bypass and purge calculations; degree of

freedom analysis. First and Second laws of thermodynamics. First law application to

substances: equation of state and departure function, properties of mixtures: partial

molar properties, fugacity, excess properties and activity coefficients; phase equilibria:

predicting VLE of systems; chemical reaction equilibria.

Fluid Mechanics and Mechanical Operations: Fluid statics, Newtonian and

non-Newtonian fluids, Bernoulli equation, Macroscopic friction factors, energy balance,

dimensional analysis, shell balances, flow through pipeline systems, flow meters,

pumps and compressors, packed and fluidized beds, elementary boundary layer

theory, size reduction and size separation; free and hindered settling; centrifuge and

cyclones; thickening and classification, filtration, mixing and agitation; conveying of

solids.

Heat Transfer: Conduction, convection and radiation, heat transfer coefficients, steady

and unsteady heat conduction, boiling, condensation and evaporation; types of heat

exchangers and evaporators and their design.

Mass Transfer: Fick’s laws, molecular diffusion in fluids, mass transfer coefficients, film,

penetration and surface renewal theories; momentum, heat and mass transfer

analogies; stagewise and continuous contacting and stage efficiencies; HTU & NTU

concepts design and operation of equipment for distillation, absorption, leaching,

liquid-liquid extraction, drying, humidification, dehumidification and adsorption.

Chemical Reaction Engineering: Theories of reaction rates; kinetics of homogeneous

reactions, interpretation of kinetic data, single and multiple reactions in ideal reactors,

ideal reactors; residence time distribution, single parameter model;

non-isothermal reactors; kinetics of heterogeneous catalytic reactions; diffusion effects in

catalysis.

Instrumentation and Process Control: Measurement of process variables; sensors,

transducers and their dynamics, transfer functions and dynamic responses of simple

systems, process reaction curve, controller modes (P, PI, and PID); control valves;

analysis of closed loop systems including stability, frequency response and controller

tuning, cascade, feed forward control.

Plant Design and Economics: Process design and sizing of chemical engineering

process economics and cost estimation including total annualized cost, cost indexes,

rate of return, payback period, discounted cash flow, optimization in design.

Chemical Technology: Inorganic chemical industries; sulfuric acid, NaOH, fertilizers

(Ammonia, Urea, SSP and TSP); natural products industries (Pulp and Paper, Sugar, Oil,

and Fats); petroleum refining and petrochemicals; polymerization industries;

polyethylene, polypropylene, PVC and polyester synthetic fibers.

GATE

Previous Year Solved Papers

Chemical Engineering - CH

Duration: 180 minutes Maximum Marks: 100

Read the following instructions carefully.

1. To login, enter your Registration Number and password provided to you. Kindly go through the various symbols used in the test and understand their meaning before you start the examination.

2. Once you login and after the start of the examination, you can view all the questions in the question paper, by clicking on the View All Questions button in the screen.

3. This question paper consists of 2 sections, General Aptitude (GA) for 15 marks and the subject specific GATE paper for 85 marks. Both these sections are compulsory.

The GA section consists of 10 questions. Question numbers 1 to 5 are of 1-mark each, while question numbers 6 to 10 are of 2-mark each.

The subject specific GATE paper section consists of 55 questions, out of which question numbers 1 to 25 are of 1-mark each, while question numbers 26 to 55 are of 2-mark each.

4. Depending upon the GATE paper, there may be useful common data that may be required for answering the questions. If the paper has such useful data, the same can be viewed by clicking on the

Useful Common Data button that appears at the top, right hand side of the screen.

5. The computer allotted to you at the examination center runs specialized software that permits only one answer to be selected for multiple-choice questions using a mouse and to enter a suitable number for the numerical answer type questions using the virtual keyboard and mouse.

6. Your answers shall be updated and saved on a server periodically and also at the end of the examination. The examination will stop automatically at the end of 180 minutes.

7. In each paper a candidate can answer a total of 65 questions carrying 100 marks.

8. The question paper may consist of questions of multiple choice type (MCQ) and numerical answer

type.

9. Multiple choice type questions will have four choices against A, B, C, D, out of which only ONE is the correct answer. The candidate has to choose the correct answer by clicking on the bubble (⃝) placed before the choice.

10. For numerical answer type questions, each question will have a numerical answer and there will not be any choices. For these questions, the answer should be enteredby using the virtual keyboard that appears on the monitor and the mouse.

11. All questions that are not attempted will result in zero marks. However, wrong answers for multiple choice type questions (MCQ) will result in NEGATIVE marks. For all MCQ questions a wrong answer will result in deduction of

⅓

marks for a 1-mark question and

⅔

marks for a 2-mark question. 12. There is NO NEGATIVE MARKING for questions of NUMERICAL ANSWER TYPE.

13. Non-programmable type Calculator is allowed. Charts, graph sheets, and mathematical tables are NOT allowed in the Examination Hall. You must use the Scribble pad provided to you at the examination centre for all your rough work. The Scribble Pad has to be returned at the end of the examination.

Declaration by the candidate:

“I have read and understood all the above instructions. I have also read and understood clearly the instructions given on the admit card and shall follow the same. I also understand that in case I am found to violate any of these instructions, my candidature is liable to be cancelled. I also confirm that at the start of the examination all the computer hardware allotted to me are in proper working condition”.

GATE 2014 Solved Paper

Chemical Enginnering - CH

Q. 1 – Q. 5 carry one mark each.

Q.1 A student is required to demonstrate a high level of comprehension of the subject, especially in the social sciences.

The word closest in meaning to comprehension is

(A) understanding (B) meaning (C) concentration (D) stability

Q.2 Choose the most appropriate word from the options given below to complete the following sentence.

One of his biggest ______ was his ability to forgive.

(A) vice (B) virtues (C) choices (D) strength

Q.3 Rajan was not happy that Sajan decided to do the project on his own. On observing his unhappiness, Sajan explained to Rajan that he preferred to work independently.

Which one of the statements below is logically valid and can be inferred from the above sentences? (A) Rajan has decided to work only in a group.

(B) Rajan and Sajan were formed into a group against their wishes. (C) Sajan had decided to give in to Rajan’s request to work with him. (D) Rajan had believed that Sajan and he would be working together. Q.4 If y = 5x2 + 3, then the tangent at x = 0, y = 3

(A) passes through x = 0, y = 0 (B) has a slope of +1 (C) is parallel to the x-axis (D) has a slope of −1

Q.5 A foundry has a fixed daily cost of Rs 50,000 whenever it operates and a variable cost of Rs 800Q, where Q is the daily production in tonnes. What is the cost of production in Rs per tonne for a daily production of 100 tonnes?

Q. 6 – Q. 10 carry two marks each.

Q.6 Find the odd one in the following group: ALRVX, EPVZB, ITZDF, OYEIK

(A) ALRVX (B) EPVZB (C) ITZDF (D) OYEIK

Q.7 Anuj, Bhola, Chandan, Dilip, Eswar and Faisal live on different floors in a six-storeyed building (the ground floor is numbered 1, the floor above it 2, and so on). Anuj lives on an even-numbered floor. Bhola does not live on an odd numbered floor. Chandan does not live on any of the floors below Faisal’s floor. Dilip does not live on floor number 2. Eswar does not live on a floor immediately above or immediately below Bhola. Faisal lives three floors above Dilip. Which of the following floor-person combinations is correct?

Anuj Bhola Chandan Dilip Eswar Faisal

(A) 6 2 5 1 3 4

(B) 2 6 5 1 3 4

(C) 4 2 6 3 1 5

Q.8 The smallest angle of a triangle is equal to two thirds of the smallest angle of a quadrilateral. The ratio between the angles of the quadrilateral is 3:4:5:6. The largest angle of the triangle is twice its smallest angle. What is the sum, in degrees, of the second largest angle of the triangle and the largest angle of the quadrilateral?

Q.9 One percent of the people of country X are taller than 6 ft. Two percent of the people of country Y are taller than 6 ft. There are thrice as many people in country X as in country Y. Taking both countries together, what is the percentage of people taller than 6 ft?

(A) 3.0 (B) 2.5 (C) 1.5 (D) 1.25

Q.10 The monthly rainfall chart based on 50 years of rainfall in Agra is shown in the following figure. Which of the following are true? (k percentile is the value such that k percent of the data fall below that value)

(i) On average, it rains more in July than in December

(ii) Every year, the amount of rainfall in August is more than that in January (iii) July rainfall can be estimated with better confidence than February rainfall (iv) In August, there is at least 500 mm of rainfall

(A) (i) and (ii) (B) (i) and (iii)

(C) (ii) and (iii) (D) (iii) and (iv)

END OF THE QUESTION PAPER

General Aptitude - GA

GATE 2014

Q. 1 – Q. 25 carry one mark each.

Q.1 Gradient of a scalar variable is always

(A) a vector (B) a scalar (C) a dot product (D) zero

Q.2 _{For the time domain function} 2 ( )

f t =t , which ONE of the following is the Laplace transform of

0

( )

?

t

f t dt

∫

(A) 3₄ s (B) 2 1 4s (C) 3 2 s (D) 4 2 s

Q.3 If f * ( )x is the complex conjugate of f x( ) =cos( )x +i sin( )x , then for real a and b,

* ( ) ( )

b

a

f x f x dx

∫

is ALWAYS

(A) positive (B) negative (C) real (D) imaginary

Q.4 If f x( )is a real and continuous function of x, the Taylor series expansion of f x( ) about its minima will NEVER have a term containing

(A) first derivative (B) second derivative (C) third derivative (D) any higher derivative

Q.5 From the following list, identify the properties which are equal in both vapour and liquid phases at equilibrium

P. Density Q. Temperature R. Chemical potential S. Enthalpy

Q.6 In a closed system, the isentropic expansion of an ideal gas with constant specific heats is represented by

(A) (B)

(C) (D)

Q.7 _{Match the following}

Group 1 Group 2 P. , , j i i T P n

G

n

≠



∂





_∂







I. Arrhenius equation Q. , , j i i S V n

G

n

≠



∂





_∂







II. Reaction equilibrium constant

R. 0

exp

G

reaction

RT



−∆











III. Chemical potential

S.

∑

(

n d

i

µ

i T P

)

,

=

0

IV. Gibbs-Duhem equation

(A) Q─III, R─I, S─II

(B) Q─III, R─II, S─IV

(C) P─III, R─II, S─IV (D) P─III, R─IV, S─I

P V P V ln(P) ln(V) ln(P) ln(V)

Q.8 In order to achieve the same conversion under identical reaction conditions and feed flow rate for a non-autocatalytic reaction of positive order, the volume of an ideal CSTR is

(A) always greater than that of an ideal PFR (B) always smaller than that of an ideal PFR (C) same as that of an ideal PFR

(D) smaller than that of an ideal PFR only for first order reaction

Q.9 Integral of the time-weighted absolute error (ITAE) is expressed as

(A) 2 0

( )

t

dt

t

ε

∞

∫

(B) 0

( )

t

dt

t

ε

∞

∫

(C) 0

( )

t

ε

t dt

∞

∫

(D) 2 0

( )

t

ε

t dt

∞

∫

Q.10 A unit IMPULSE response of a first order system with time constantτ and steady state gain

K

_p is given by (A)

1

t/ p

e

K

τ

τ

(B)

K e

_p

−

t

/

τ

_(C)

τ

K e

_p −t/τ _(D)

K

p

e

t/

τ

τ

−

Q.11 In a completely opaque medium, if 50% of the incident monochromatic radiation is absorbed, then which of the following statements are CORRECT?

P. 50% of the incident radiation is reflected Q. 25% of the incident radiation is reflected R. 25% of the incident radiation is transmitted S. No incident radiation is transmitted

(A) P and S only (B) Q and R only (C) P and Q only (D) R and S only

Q.12 In case of a pressure driven laminar flow of a Newtonian fluid of viscosity (µ) through a horizontal circular pipe, the velocity of the fluid is proportional to

Q.13 Which of the following statements are CORRECT?

P. For a rheopectic fluid, the apparent viscosity increases with time under a constant applied shear stress

Q. For a pseudoplastic fluid, the apparent viscosity decreases with time under a constant applied shear stress

R. For a Bingham plastic, the apparent viscosity increases exponentially with the deformation rate S. For a dilatant fluid, the apparent viscosity increases with increasing deformation rate

(A) P and Q only (B) Q and R only (C) R and S only (D) P and S only

Q.14 Assume that an ordinary mercury-in-glass thermometer follows first order dynamics with a time constant of 10 s. It is at a steady state temperature of 0 °C. At time t = 0, the thermometer is suddenly immersed in a constant temperature bath at 100 °C. The time required (in s) for the thermometer to read 95 °C, approximately is

(A) 60 (B) 40 (C) 30 (D) 20

Q.15 Packed towers are preferred for gas-liquid mass transfer operations with foaming liquids because

(A) in packed towers, high liquid to gas ratios are best handled (B) in packed towers, continuous contact of gas and liquid takes place (C) packed towers are packed with random packings

(D) in packed towers, the gas is not bubbled through the liquid pool

Q.16 A spherical storage vessel is quarter–filled with toluene. The diameter of the vent at the top of the vessel is 1/20th of the diameter of the vessel. Under the steady state condition, the diffusive flux of toluene is maximum at

(A) the surface of the liquid (B) the mid-plane of the vessel (C) the vent

(D) a distance 20 times the diameter of the vent away from the vent

Q.17 In order to produce fine solid particles between 5 and 10 µm, the appropriate size reducing equipment is

(A) fluid energy mill (B) hammer mill

(C) jaw crusher (D) smooth roll crusher

Q.18 Slurries are most conveniently pumped by a

(A) syringe pump (B) diaphragm pump

(C) vacuum pump (D) gear pump

Q.19 Assuming the mass transfer coefficients in the gas and the liquid phases are comparable, the absorption of CO2 from reformer gas (CO2+H2) into an aqueous solution of diethanolamine is

controlled by

(A) gas phase resistance (B) liquid phase resistance

(C) both gas and liquid phase resistances (D) composition of the reformer gas

Q.20 Which ONE of the following statements is CORRECT for the surface renewal theory? (A) Mass transfer takes place at steady state

(B) Mass transfer takes place at unsteady state (C) Contact time is same for all the liquid elements (D) Mass transfer depends only on the film resistance

Q.21 Steam economy of a multiple effect evaporator system is defined as (A) kilogram of steam used per hour

(B) kilogram of steam consumed in all the effects for each kilogram of steam fed

(C) kilogram of steam used in all the effects for each kilogram of water vaporized per hour (D) kilogram of water vaporized from all the effects for each kilogram of steam fed to the first effect

Q.22 _{Decomposition efficiency (}

η

_{D) of an electrolytic cell used for producing NaOH is defined as} (A)

η

D = (grams of NaOH produced / grams of NaCl decomposed) x 100

(B)

η

D = (grams of NaOH produced / grams of NaCl charged) x 100

(C)

η

D = (gram equivalents of NaOH produced / gram equivalents of NaCl charged) x 100

(D)

η

D = (theoretical current to produce one gram equivalent / actual current to produce one gram

Q.23 The vessel dispersion number for an ideal CSTR is

(A) ─1 (B) 0 (C) 1 (D)

∞

Q.24 Catalytic cracking is

(A) a hydrogen addition process (B) a carbon rejection process (C) an exothermic process (D) a coking process

Q.25 Which ONE of the following statements is CORRECT?

(A) The major components of biodiesel are triglycerides (B) Biodiesel is essentially a mixture of ethyl esters (C) Biodiesel is highly aromatic

(D) Biodiesel has a very low aniline point

Q. 26 – Q. 55 carry two marks each.

Q.26 Consider the following differential equation

ln( ) ; 2 at 0

dy

x y y x dx = + = =

The solution of this equation at x=0.4using Euler method with a step size of h=0.2

is___________

Q.27 The integrating factor for the differential equation

(1 ) 1 dy y x dx− +x= + is (A) 1 1 x+ (B) (1+x) (C) x(1+x) (D) 1 x x +

Q.28

The differential equation

2 2 3 2 x d y dy x x y e dx + dx+ = is a

(A) non-linear differential equation of first degree (B) linear differential equation of first degree (C) linear differential equation of second degree (D) non-linear differential equation of second degree

Q.29 Consider the following two normal distributions

2 1

( )

exp(

)

f x

=

−

π

x

2 2 1 1 ( ) exp ( 2 1) 2 4 f x x x

π

π

  = _− + + _  

If

µ

and

σ

denote the mean and standard deviation, respectively, then

(A)

µ µ

₁

<

₂ and

σ

₁2

<

σ

₂2 (B)

µ µ

₁

<

₂ and

σ

₁2

>

σ

₂2 (C)

µ

₁

>

µ

₂ and

σ

₁2

<

σ

₂2 (D)

µ

₁

>

µ

₂ and

σ

₁2

>

σ

₂2

Q.30 In rolling of two fair dice, the outcome of an experiment is considered to be the sum of the numbers appearing on the dice. The probability is highest for the outcome of ____________

Q.31 A spherical ball of benzoic acid (diameter = 1.5 cm) is submerged in a pool of still water. The solubility and diffusivity of benzoic acid in water are 0.03 kmol/m3 and 1.25 x 10-9 m2/s respectively. Sherwood number is given as Sh = 2.0 + 0.6 Re0.5Sc0.33. The initial rate of dissolution (in kmol/s) of benzoic acid approximately is

(A) 3.54×10-11 (B) 3.54×10-12 (C) 3.54×10-13 (D) 3.54×10-14

Q.32 A wet solid of 100 kg is dried from a moisture content of 40 wt% to 10 wt%. The critical moisture content is 15 wt% and the equilibrium moisture content is negligible. All moisture contents are on dry basis. The falling rate is considered to be linear. It takes 5 hours to dry the material in the constant rate period. The duration (in hours) of the falling rate period is ___________

Q.33 A brick wall of 20 cm thickness has thermal conductivity of 0.7 W m-1 K-1. An insulation of thermal conductivity 0.2 W m-1 K-1 is to be applied on one side of the wall, so that the heat transfer through the wall is reduced by 75%. The same temperature difference is maintained across the wall before and after applying the insulation. The required thickness (in cm) of the insulation is ____________

Q.34 An oil with a flow rate of 1000 kg/h is to be cooled using water in a double-pipe counter-flow heat exchanger from a temperature of 70 °C to 40 °C. Water enters the exchanger at 25 °C and leaves at 40 °C. The specific heats of oil and water are 2 kJ kg-1 K-1 and 4.2 kJ kg-1 K-1, respectively. The overall heat transfer coefficient is 0.2 kW m-2 K-1. The minimum heat exchanger area (in m2) required for this operation is ______________

Q.35 Which ONE of the following is CORRECT for an ideal gas in a closed system? (A) S V

U

U

V

nR

V

S

∂

∂





₌







_∂





_∂











(B) S P

H

H

P

nR

P

S

∂

∂









−

_

_

=

_

_

∂

∂









(C) S P

U

H

V

nR

V

S

∂

∂





₌







_∂





_∂











(D) S V

H

U

P

nR

P

S

∂

∂





₌







_∂





_∂











Q.36 A binary distillation column is operating with a mixed feed containing 20 mol% vapour. If the feed quality is changed to 80 mol% vapour, the change in the slope of the q-line is ________________

Q.37 A homogeneous reaction

(

R→P

)

occurs in a batch reactor. The conversion of the reactant R is 67% after 10 minutes and 80% after 20 minutes. The rate equation for this reaction is

(A)

− =

r

_R

k

(B)

− =

r

_R

k C

_R2

(C)

− =

r

_R

k C

_R3 (D) − =r_R k C_R0.5

Q.38 A vapour phase catalytic reaction

(

Q+ →R S

)

follows Rideal mechanism (R and S are not adsorbed). Initially, the mixture contains only the reactants in equimolar ratio. The surface reaction step is rate controlling. With constants a and b, the initial rate of reaction

( )

−

r

_o in terms of total pressure

( )

P

T is given by (A) 1 T o T aP r bP − = + (B) 2

1

T o T

aP

r

bP

− =

+

(C) 2

1

T o T

aP

r

bP

− =

+

(D) 2 2

(1

)

T o T

aP

r

bP

− =

+

Q.39 An incompressible fluid is flowing through a contraction section of length L and has a 1-D (x-direction) steady state velocity distribution, u u₀ 1 2x

L

 

= _ + _

 . If u0 = 2 m/s and L = 3 m, the

convective acceleration (in m/s2) of the fluid at L is _____________

Q.40 Match the following

Group 1 Group 2

P. Tank in series model I. Non-isothermal reaction Q. Liquid-liquid extraction II. Mixer-settler

R. Optimum temperature progression III. PFR with axial mixing S. Thiele modulus IV. Solid catalyzed reaction

(A) P─II, Q─IV, R─I, S─III (B) P─I, Q─II, R─III, S─IV (C) P─III, Q─I, R─II, S─IV (D) P─III, Q─II, R─I, S─IV

Q.41 Two elemental gases (A and B) are reacting to form a liquid (C) in a steady state process as per the reactionA+ →B C. The single-pass conversion of the reaction is only 20% and hence recycle is used. The product is separated completely in pure form. The fresh feed has 49 mol% of A and B each along with 2 mol% impurities. The maximum allowable impurities in the recycle stream is 20 mol%. The amount of purge stream (in moles) per 100 moles of the fresh feed is ___________

Q.42 Carbon monoxide (CO) is burnt in presence of 200% excess pure oxygen and the flame temperature achieved is 2298 K. The inlet streams are at 25 °C. The standard heat of formation (at 25°C) of CO and CO2 are ─110 kJ mol

-1

and ─390 kJ mol-1, respectively. The heat capacities (in J mol-1 K-1) of the components are

2 2 3 3

25 14 10

25 42 10

O CO p p

C

T

C

T

− −

=

+ ×

=

+

×

where, T is the temperature in K. The heat loss (in kJ) per mole of CO burnt is_____________

Q.43 A cash flow of Rs. 12,000 per year is received at the end of each year (uniform periodic payment) for 7 consecutive years. The rate of interest is 9% per year compounded annually. The present worth (in Rs.) of such cash flow at time zero is __________

Q.44 A polymer plant with a production capacity of 10,000 tons per year has an overall yield of 70%, on mass basis (kg of product per kg of raw material). The raw material costs Rs. 50,000 per ton. A process modification is proposed to increase the overall yield to 75% with an investment of Rs. 12.5 crore. In how many years can the invested amount be recovered with the additional profit? ___________

Q.45 A step change of magnitude 2 is introduced into a system having the following transfer function

2 2 ( ) 2 4 G s s s = + +

The percent overshoot is ____________

Q.46 Given below is a simplified block diagram of a feedforward control system.

The transfer function of the process is 5

1

p

G s

=

+ and the disturbance transfer function is 2 1 2 1 d G s s =

+ + . The transfer function of the PERFECT feedforward controller,

G s

f

( )

is (A) 5 ₃ (s 1) − + (B) 5 (s 1) − + (C) 1 5(s 1) − + (D) −5(s+1)

Q.47 The bottom face of a horizontal slab of thickness 6 mm is maintained at 300 °C. The top face is exposed to a flowing gas at 30 °C. The thermal conductivity of the slab is 1.5 W m-1 K-1 and the convective heat transfer coefficient is 30 W m-2 K-1. At steady state, the temperature (in °C) of the top face is __________

Q.48 _{In a steady incompressible flow, the velocity distribution is given by}

_V



₌

₃

_xi

ˆ

₋

_Pyj

ˆ

₊

₅

_zk

ˆ

_{, where,}

V is in m/s and x, y, and z are in m. In order to satisfy the mass conservation, the value of the constantP (in s-1) is __________

Q.49 Match the following

Group 1 Group 2

P. Turbulence I. Reciprocating pump

Q. NPSH II. Packed bed

R. Ergun equation III. Fluctuating velocity

S. Rotameter IV. Impeller

T. Power number V. Vena contracta

(A) P─III, R─II, T─IV (B) Q─V, R─II, S─III (C) P─III, R─IV, T─II (D) Q─III, S─V, T─IV

Q.50 In a steady and incompressible flow of a fluid (density = 1.25 kg m-3), the difference between stagnation and static pressures at the same location in the flow is 30 mm of mercury (density = 13600 kg m-3). Considering gravitational acceleration as 10 m s-2, the fluid speed (in m s-1) is ______________

Q.51 Consider a binary liquid mixture at equilibrium with its vapour at 25 °C. Antoine equation for this system is given as

log

10

sat i

B

p

A

t

C

= −

+

where t is in °C and p in Torr. The Antoine constants (A, B, and C) for the system are given in the following table.

Component A B C

1 7.0 1210 230

2 6.5 1206 223

The vapour phase is assumed to be ideal and the activity coefficients (

γ

_i) for the non-ideal liquid phase are given by

2 1 2 1 2 2 1 2

ln( )

[2 0.6 ]

ln(

)

[1.7 0.6 ]

x

x

x

x

γ

γ

=

−

=

+

If the mole fraction of component 1 in liquid phase (x1) is 0.11, then the mole fraction of

component 1 in vapour phase (y1) is ___________

Q.52

A process with transfer function, 2

1

p

G s

=

− is to be controlled by a feedback proportional

controller with a gain Kc. If the transfer functions of all other elements in the control loop are unity,

then which ONE of the following conditions produces a stable closed loop response?

(A)

K

_c

=

0.25

(B)

0

<

K

_c

<

0.25

(C)

0.25

<

K

_c

<

0.5

(D)

K

_c

>

0.5

Q.53 Consider the following block diagram for a closed-loop feedback control system

A proportional controller is being used with

K

_c

= −

4

. If a step change in disturbance of magnitude 2 affects the system, then the value of the offset is ____________

Q.54 Determine the correctness or otherwise of the following Assertion [a] and Reason [r].

Assertion: Significant combustion of coke takes place only if it is heated at higher temperature in

presence of air.

Reason:

C + O

₂

→

CO

₂is an exothermic reaction.

(A) Both [a] and [r] are true and [r] is the correct reason for [a] (B) Both [a] and [r] are true but [r] is not the correct reason for [a] (C) [a] is correct but [r] is false

Q.55 Match the raw materials of Groups 1 and 2 with the final products of Group 3 Group 1 Group 2 Group 3

P1: Ethylene Q1: Ammonia R1: Synthetic fibre

P2: Propylene Q2: 1-Butene R2: Nylon 66

P3: Adipic acid Q3: Ethylene glycol R3: LLDPE

P4: Terephthalic acid Q4: Hexamethylene diamine R4: Acrylonitrile

(A) P1+Q2→R3; P2+Q1→R4; P3+Q4→R2; P4+Q3→R1

(B) P1+Q1→R3; P2+Q3→R1; P3+Q4→R4; P4+Q2→R2

(C) P1+Q2→R2; P2+Q3→R1; P3+Q4→R3; P4+Q1→R4

(D) P1+Q1→R4; P2+Q2→R3; P3+Q4→R2; P4+Q3→R1

END OF THE QUESTION PAPER

GATE 2014 - Answer Keys

General Aptitude– GA

Q. No.

Key / Range Q. No.

Key / Range Q. No.

Key / Range

1

A

5

1300 to 1300 9

D

2

B

6

D

10

B

3

D

7

B

4

C

8

180 to 180

Chemical Engineering - CH

Q. No.

Key / Range Q. No.

Key / Range Q. No.

Key / Range

1

A

20

B

39

7.99 to 8.01

2

D

21

D

40

D

3

C

22

C

41

9.99 to 10.01

4

A

23

D

42

32.0 to 38.0

5

B

24

B

43

60000 to

61000

6

D

25

B

44

2.55 to 2.70

7

C

26

2.3 to 2.4

45

16.0 to 16.8

8

A

27

A

46

C

9

C

28

B

47

268 to 274

10

D

29

C

48

7.99 to 8.01

11

A

30

6.99 to 7.01

49

A

12

C

31

B

50

79 to 82

13

D

32

1.1 to 1.3

51

0.65 to 0.75

14

C

33

17.0 to 17.03 52

D

15

D

34

3.75 to 3.95

53

0.49 to 0.51

16

C

35

D

54

B

17

A

36

3.6 to 3.9

55

A

18

B

37

B

19

A

38

C

Paper specific instructions:

1. There are a total of 65 questions carrying 100 marks.Questions are of multiple choice type or numerical answer type. A multiple choice type question will have four choices for the answer with only one correct choice. For numerical answer type questions, the answer is a number and no choices will be given. A number as the answer should be entered using the virtual keyboard on the monitor. 2. Questions Q.1 – Q.25 carry 1mark each. Questions Q.26 – Q.55 carry 2marks each. The 2marks questions include two pairs of common data questions and two pairs of linked answer questions. The answer to the second question of the linked answer questions depends on the answer to the first question of the pair. If the first question in the linked pair is wrongly answered or is not attempted, then the answer to the second question in the pair will not be evaluated.

3. Questions Q.56 – Q.65 belong to General Aptitude (GA) section and carry a total of 15 marks. Questions Q.56 – Q.60 carry 1mark each, and questions Q.61 – Q.65 carry 2marks each.

4. Questions not attempted will result in zero mark. Wrong answers for multiple choice type questions will result in NEGATIVE marks. For all 1 mark questions,

⅓

mark will be deducted for each wrong answer. For all 2 marks questions,

⅔

mark will be deducted for each wrong answer. However, in the case of the linked answer question pair, there will be negative marks only for wrong answer to the first question and no negative marks for wrong answer to the second question. There is no negative marking for questions of numerical answer type.

5. Calculator is allowed. Charts, graph sheets or tables are NOT allowed in the examination hall. 6. Do the rough work in the Scribble Pad provided.

Duration: Three Hours Maximum Marks:100

GATE 2013

Chemical Engg. - CH

GATE 2013 Solved Paper

Chemical Engineering - CH

Q. 1 – Q. 25 carry one mark each.

Q.1 The number of emails received on six consecutive days is 11, 9, 18, 18, 4 and 15, respectively. What are the median and the mode for these data?

(A) 18 and 11, respectively (B) 13 and 18, respectively (C) 13 and 12.5, respectively (D) 12.5 and 18, respectively

Q.2 For two rolls of a fair die, the probability of getting a 4 in the first roll and a number less than 4 in the second roll, up to 3 digits after the decimal point, is _________

Q.3 Which of the following statements are TRUE? P. The eigenvalues of a symmetric matrix are real

Q. The value of the determinant of an orthogonal matrix can only be +1 R. The transpose of a square matrix A has the same eigenvalues as those of A S. The inverse of an ‘n × n’ matrix exists if and only if the rank is less than ‘n’

(A) P and Q only (B) P and R only (C) Q and R only (D) P and S only Q.4 Evaluate

1

x

dx

e





( Note: C is a constant of integration.) (A) 1  x x e C e (B)





ln



1



x x

e

C

e

(C)

ln

1









_







x x

e

C

e

(D)

ln 1





x

e



C





Q.5 A gaseous system contains H2, I2, and HI, which participate in the gas-phase reaction

2 2 2 HIH + I

At a state of reaction equilibrium, the number of thermodynamic degrees of freedom is _________

Q.6 The thermodynamic state of a closed system containing a pure fluid changes from (T1, p1) to

(T2, p2), where T and p denote the temperature and pressure, respectively. Let Q denote the heat

absorbed (> 0 if absorbed by the system) and W the work done (> 0 if done by the system). Neglect changes in kinetic and potential energies. Which one of the following is CORRECT?

(A)Q is path-independent and W is path-dependent (B)Q is path-dependent and W is path-independent (C) (Q − W) is path-independent

Q.7 An equation of state is explicit in pressure p and cubic in the specific volume v. At the critical point ‘c’, the isotherm passing through ‘c’ satisfies

(A) 2 2 0, 0 p p v v  _  _   (B) 2 2 0, 0 p p v v  _  _   (C) 2 2 0, 0 p p v v  _  _   (D) 2 2 0, 0 p p v v  _  _  

Q.8 The units of the isothermal compressibility are

(A) m-3 (B) Pa-1 (C) m3 Pa-1 (D) m-3 Pa-1

Q.9 An open tank contains two immiscible liquids of densities (800 kg/m3 and 1000 kg/m3) as shown in the figure. If g = 10 m/s2, under static conditions, the gauge pressure at the bottom of the tank in Pa is ___________

Q.10 The apparent viscosity of a fluid is given by

0.3

0.007

dV

dy

where

dV

dy













is the velocity gradient. The fluid is

(A) Bingham plastic (B) dilatant (C) pseudoplastic (D) thixotropic Q.11

The mass balance for a fluid with density (and velocity vector

V



 

 

 

is (A) V 0 t



_

  _{  } _      (B) t V

 

0





_

 _{   }  (C) V 0 t

 

  _{ }  _  _    (D) t V

 

0





  _{   } 

Q.12 An incompressible Newtonian fluid, filled in an annular gap between two concentric cylinders of radii R1 and R2 as shown in the figure, is flowing under steady state conditions. The outer cylinder

is rotating with an angular velocity of  while the inner cylinder is stationary. Given that



R2R1



R1, the profile of the -component of the velocity V can be approximated by,

(A)

R

₂



(B)







2 21









r

R

r

R

R

(C)







1



1 2 1

r

R

R

R

R







(D)







1



2 2 1

r

R

R

R

R







Q.13 For a Newtonian fluid flowing in a circular pipe under steady state conditions in fully developed laminar flow, the Fanning friction factor is

(A) 0.046 Re0.2 (B) 0.0014 0.125_0.32 Re  (C) 16 Re (D) 24 Re

Q.14 In the Tyler standard screen scale series, when the mesh number increases from 3 mesh to 10 mesh, then

(A) the clear opening decreases (B) the clear opening increases (C) the clear opening is unchanged (D) the wire diameter increases

Q.15 Taking the acceleration due to gravity to be 10 m/s2, the separation factor of a cyclone 0.5 m in diameter and having a tangential velocity of 20 m/s near the wall is _________

R1

R2

r

W

Q.16 The effectiveness of a heat exchanger in the -NTU method is defined as (A) increase in temperature of the cold fluid

decrease in temperature of the hot fluid

(B) actual exit temperature attained by the cold fluid maximum exit temperature attainable by the cold fluid (C) actual exit temperature attained by the hot fluid

minimum exit temperature attainable by the hot fluid (D) actual heat transfer rate

maximum possible heat transfer rate from hot fluid to cold fluid Q.17 In a pool boiling experiment, the following phenomena were observed.

P. Natural convection Q. Film boiling R. Transition boiling S. Nucleate boiling

What was the CORRECT sequence of their occurrence?

(A) P, Q, R, S (B) S, R, Q, P (C) Q, R, P, S (D) P, S, R, Q

Q.18 A hole of area 1 cm2 is opened on the surface of a large spherical cavity whose inside temperature is maintained at 727 °C. The value of Stefan-Boltzmann constant is 5.67×10-8 W/m2-K4. Assuming black body radiation, the rate at which the energy is emitted (in W) by the cavity through the hole, up to 3 digits after the decimal point, is ________

Q.19 The packing of an existing absorption tower is replaced with a new type of packing. The height of the packing and the inlet conditions are maintained the same as before. Tests reveal that the number of transfer units is lower than before. This indicates that the tower with the new packing, when compared to that with the old packing, will

(A) have a higher rate of absorption of the solute from the gas stream (B) have a lower rate of absorption of the solute from the gas stream (C) have the same rate of absorption of the solute from the gas stream (D) have a lower height of transfer unit

Q.20 A wet solid is dried over a long period of time by unsaturated air of nonzero constant relative humidity. The moisture content eventually attained by the solid is termed as the

(A) unbound moisture content (B) bound moisture content (C) free moisture content

Q.21 The exit age distribution for a reactor is given by E(t) = (t - 4), where t is in seconds. A first order liquid phase reaction (k = 0.25 s-1) is carried out in this reactor under steady state and isothermal conditions. The mean conversion of the reactant at the exit of the reactor, up to 2 digits after the decimal point, is __________

Q.22 An isothermal liquid phase zero order reaction A  B (k = 0.5 mol/m3-s) is carried out in a batch reactor. The initial concentration of A is 2 mol/m3. At 3 seconds from the start of the reaction, the concentration of A in mol/m3 is __________

Q.23 The overall rates of an isothermal catalytic reaction using spherical catalyst particles of diameters 1 mm and 2 mm are rA1 and rA2 (in mol (kg-catalyst)-1 h-1), respectively. The other physical

properties of the catalyst particles are identical. If pore diffusion resistance is very high, the ratio rA2/rA1 is __________

Q.24 In the manufacture of sulphuric acid by the contact process, the catalytic oxidation of SO2 is carried

out in multiple stages mainly to

(A) increase the reaction rate by providing inter-stage heating (B) increase the overall conversion by providing inter-stage heating (C) increase the overall conversion by providing inter-stage cooling

(D) decrease the overall conversion by removing sulphur trioxide between stages

Q.25 Match the following.

Group 1 Group 2

(P) Viscosity (1) Pyrometer

(Q) Pressure (2) Hot wire anemometer (R) Velocity (3) Rheometer

(S) Temperature (4) Piezoelectric element

(A) P-4, Q-3, R-1, S-2 (B) P-3, Q-4, R-2, S-1 (C) P-3, Q-4, R-1, S-2 (D) P-4, Q-3, R-2, S-1

Q. 26 to Q. 55 carry two marks each.

Q.26 For the function

    

1 2 2 f z z z    the residue at z = 2 is _________

Q.27 The solution of the differential equation 2 0 dy y dx  , given

y



1

at

x



0

is (A) 1 1 x (B) 1 1 x (C)





2

1

1 x



(D) 3 1 3 x 

Q.28 The solution of the differential equation

2 2 0.25 0 d y dy y dx dx  , given

y



0 at

x



0

and 1 at 0 dy x dx   is (A) x e0.5x x e0.5x (B) 0.5x ex0.5x ex (C) x e0.5x (D) x e0.5x

Q.29 The value of the integral

∫

_..

evaluated by Simpson’s rule using 4 subintervals (up to 3 digits after the decimal point) is ____

Q.30 In a process occurring in a closed system F, the heat transferred from F to the surroundings E is 600 J. If the temperature of E is 300 K and that of F is in the range 380 - 400 K, the entropy changes of the surroundings (ΔSE) and system (ΔSF), in J/K, are given by

(A) ΔSE = 2, ΔSF = -2 (B) ΔSE = -2, ΔSF = 2

(C) ΔSE = 2, ΔSF < -2 (D) ΔSE = 2, ΔSF > -2

Q.31 A binary liquid mixture is in equilibrium with its vapor at a temperature T = 300 K. The liquid mole fraction x1 of species 1 is 0.4 and the molar excess Gibbs free energy is 200 J/mol. The value

of the universal gas constant is 8.314 J/mol-K, and i denotes the liquid-phase activity coefficient of

species i. If ln(1) = 0.09, then the value of ln(2), up to 2 digits after the decimal point, is ________

Q.32 Water (density 1000 kg/m3) is flowing through a nozzle, as shown below and exiting to the atmosphere. The relationship between the diameters of the nozzle at locations 1 and 2 is D1 = 4 D2.

The average velocity of the stream at location 2 is 16 m/s and the frictional loss between location 1 and location 2 is 10000 Pa. Assuming steady state and turbulent flow, the gauge pressure in Pa, at location 1 is ___________

Q.33 In the elutriation leg of a commercial crystallizer containing a mixture of coarse and very fine crystals of the same material, a liquid is pumped vertically upward. The liquid velocity is adjusted such that it is slightly lower than the terminal velocity of the coarse crystals only. Hence

(A) the very fine and coarse crystals will both be carried upward by the liquid (B) the very fine and coarse crystals will both settle at the bottom of the tube (C) the very fine crystals will be carried upward and the coarse crystals will settle (D) the coarse crystals will be carried upward and the very fine crystals will settle

Q.34 100 ton/h of a rock feed, of which 80% passed through a mesh size of 2.54 mm, were reduced in size such that 80% of the crushed product passed through a mesh size of 1.27 mm. The power consumption was 100 kW. If 100 ton/h of the same material is similarly crushed from a mesh size of 5.08 mm to a mesh size of 2.54 mm, the power consumption (in kW, to the nearest integer) using Bond’s law, is _____________

Q.35 Calculate the heat required (in kJ, up to 1 digit after the decimal point) to raise the temperature of 1 mole of a solid material from 100 °C to 1000 °C. The specific heat (Cp) of the material (in

J/mol-K) is expressed as Cp = 20 + 0.005T, where T is in K. Assume no phase change. _________

Q.36 In a double pipe counter-current heat exchanger, the temperature profiles shown in the figure were observed. During operation, due to fouling inside the pipe, the heat transfer rate reduces to half of the original value. Assuming that the flow rates and the physical properties of the fluids do not change, the LMTD (in °C) in the new situation is

Q.37 The vapor-liquid equilibrium curve of a binary mixture A-B, may be approximated by a linear equation over a narrow range of liquid mole fractions ( 0.2 <

x

_A< 0.3) as follows

*

1.325 0.121

A A

y  x 

Herey*_A is the mole fraction of A in the vapor. 100 moles of a feed (x_{A F,} = 0.28) is batch distilled to a final residue (x_{A W,} = 0.2). Using the Rayleigh equation, the number of moles of the residue left behind in the distillation unit, up to 2 digits after the decimal point, is ____________

Q.38 A crosscurrent cascade of N ideal stages is used to treat a feed stream of molar flow rate E. The feed stream contains a solute which is to be recovered by a pure solvent having a molar flow rate S. The solvent is divided equally between these N stages. The linear equilibrium curve relating the mole fractions x and y* of the solute in the raffinate and the extract respectively, is given by y* = m x. Assume dilute conditions. The ratio of the solute mole fraction in the original feed to that in the exit raffinate stream i.e.



x / x_{0 N}



is given by

(A) _1  __     N mS NE (B) _1  __     N NS mE (C) _1  __     N NE mS (D) _1  __     N mE NS

Q.39 A study was conducted in which water was pumped through cylindrical pipes made of a sparingly soluble solid. For a given pipe and certain flow conditions, the mass transfer coefficient kc has been

calculated as 1 mm/s using the correlation

Sh = 0.025 Re 0.6 Sc 0.33

If the velocity of the fluid and the diameter of the pipe are both doubled, what is the new value of kc

in mm/s, up to 2 digits after the decimal point? ____________

Q.40 The gas phase decomposition of azomethane to give ethane and nitrogen takes place according to the following sequence of elementary reactions.

(CH3)2N2 + (CH3)2N2

→

(CH3)2N2 + [(CH3)2N2]*

[(CH3)2N2]* + (CH3)2N2

→

(CH3)2N2 + (CH3)2N2

[(CH3)2N2]*

→

C2H6 + N2

Using the pseudo-steady-state-approximation for [(CH3)2N2]*, the order with respect to azomethane

in the rate expression for the formation of ethane, in the limit of high concentrations of azomethane, is ___________

Q.41 A first order liquid phase reaction is carried out isothermally at a steady state in a CSTR and 90% conversion is attained. With the same inlet conditions and for the same overall conversion, if the CSTR is replaced by two smaller and identical isothermal CSTRs in series, the % reduction in total volume, to the nearest integer, is ____________

Q.42 Match the reactant-product combination in Group 1 with the unit process in Group 2.

Group 1 Group 2

(P) propylene - butanol (1) Pyrolysis

(Q) cumene - phenol (2) Dehydrogenation (R) butane - butadiene (3) Hydroformylation (S) ethylene dichloride - vinyl chloride (4) Peroxidation

(A) P-3, Q-2, R-4, S-1 (B) P-2, Q-4, R-3, S-1 (C) P-1, Q-3, R-2, S-4 (D) P-3, Q-4, R-2, S-1

Q.43 Identify which of the following statements are FALSE.

(P) Oils with an oleic radical (1 double bond) are more suitable than oils with a linolenic radical (3 double bonds) as film forming vehicles for paints

(Q) Production of synthesis gas from coal and steam is an endothermic process (R) Use of chlorine for bleaching of wood pulp results in the release of dioxins

(S) In the manufacture of urea from ammonia, the main intermediate product formed is ammonium bicarbonate

(A) P and Q only (B) R and S only

(C) Q and R only (D) P and S only

Q.44 A unit gain 2nd order underdamped process has a period of oscillation 1 second and decay ratio 0.25. The transfer function of the process is

(A) ₂ 1 0.024s 0.067s1 (B) 2 1 0.067s 0.024s1 (C) 2 1 0.021s 0.1176s1 (D) 2 1 0.1176s 0.021s1

Q.45 A control valve, with a turndown ratio of 50, follows equal percentage characteristics. The flow rate of a liquid through the valve at 40% stem position is 1 m3/h. What will be the flow rate in m3/h at 50% stem position, if the pressure drop across the valve remains unchanged? (Up to 2 digits after the decimal point.) ________

Q.46 The purchase cost of a heat exchanger of 20 m2 area was Rs. 500000 in 2006. What will be the estimated cost (in Rs. to the nearest integer) of a similar heat exchanger of 50 m2 area in the year 2013? Assume the six-tenths factor rule for scaling and the cost index for 2006 as 430.2. The projected cost index for the year 2013 is 512.6. _________

Q.47 A plant manufactures compressors at the rate of N units/day. The daily fixed charges are Rs. 20000 and the variable cost per compressor is Rs. 500 + 0.2 N1.3. The selling price per compressor is Rs. 1000. The number of compressors to be manufactured, to the nearest integer, in order to maximize the daily profit is ___________

Common Data Questions

Common Data for Questions 48 and 49:

A reverse osmosis unit treats feed water (F) containing fluoride and its output consists of a permeate stream (P) and a reject stream (R). Let CF, CP, and CR denote the fluoride concentrations in the feed, permeate, and

reject streams, respectively. Under steady state conditions, the volumetric flow rate of the reject is 60 % of the volumetric flow rate of the inlet stream, and CF = 2 mg/L and CP = 0.1 mg/L.

Q.48 The value of CR in mg/L, up to one digit after the decimal point, is _________

Q.49 A fraction f of the feed is bypassed and mixed with the permeate to obtain treated water having a fluoride concentration of 1 mg/L. Here also the flow rate of the reject stream is 60% of the flow rate entering the reverse osmosis unit (after the bypass). The value of f , up to 2 digits after the decimal point, is __________

Common Data for Questions 50 and 51:

Liquid reactant A decomposes as follows

A  R r_R k C₁ 2_A k1 = 0.5 m 3

/mol-s A  S r_S k C_{2 A} k2 = 1 s

-1

An aqueous feed of composition CA0 = 30 mol/m 3 , CR0 = 2 mol/m 3 , and CS0= 1 mol/m 3 enters a CSTR in which the above reactions occur. Assume isothermal and steady state conditions.

Q.50 If the conversion of A is 80 %, the concentration of R in the exit stream in mol/m3, to the nearest integer, is _________