Q 1. Verify the the authenticity of the statements: (i) (ii) (iii) (iv)
The thermal conductivity of liquid usually decreases with the increase in tem perature Critical Radius will be more in forced convection than in free convection Rate of Heat Transfer will always decre ase with increase in insulation of a plane wall Increasing the number of fins in a car radiator, will always result in increase in overall heat transfer, but this is usually not practiced due to expensive fin material
(a) TTFT (b) TFFF
(c) FFTT
(d) TFTF
Questions 2&3 are common data based questions Consider the following transfer function: (Note: The unit of the process time constant is in seconds.) G p(s) = 5/(2s+1)4 Q 2. The crossover crossover frequency (in rad/s) of the process process is (A) 20 (B) 0.1 (C) 0.5 (D) 0.05 Q 3. For the computation computation of Ziegler-Nichols Ziegler-Nichol s settings, the ultimate period (in s/cycle) and the ultimate gain are: (A) π and 0.8, respectively (B) 4 π and 0.8, respectively (C) 4π and 1.25, respectively (D) π and 1.25, respectively
Questions 4 and 5 are common data based questions: In a pharmaceutical industry a drying test with a solid material is done .It shows relation for the falling rate period of drying as dX/dt = -0.5(X-0.08) Where X is moisture content on dry basis and t is time in hours. The critical moisture content is 1.5 kg moisture per kg of dry material. Q 4. Calculate the time required in hours for drying the material from initial moisture content content of 4.5 to 0.4 moisture content on dry basis. a.)5
b.)7.9
c.)8.75
d.)9
Q 5. Find the equilibrium moisture content for the above drying process. a.)0.1
b.)0.05
d.)0.08
d.)0.12
Q 6. Relate the Dimensionless numbers with its significance.
(a) (b) (c) (d)
Biot Number (i) The relative thickness of the velocity and the thermal boundary layers Nusselt Number (ii) Inertia forces and viscous forces Reynolds Number (iii) Temperature gradient within the body Prandtl Number (iv) Enhancement of heat transfer through a fluid layer as a result of convection relative to conduction across the same fluid layer.
(A) a - iii; b - iv; c - ii; d – i (B) a - iv; b - iii; c - i; d – ii
(C) a - i; b - iv; c - ii; d – iii (D) a - iii; b - iv; c - ii; d – i
Q 7. T he Bode stability criterion is applicable when (A) Gain and phase curves decrease continuously with frequency (B) Gain curve increases and phase curve decreases with frequency (C) Gain curve and phase curve both increase with frequency (D) Gain curve decreases and phase curve increases with frequency Q 8. A thermometer initially at 100°C is dipped at t = 0 into an oil bath, maintained at 150°C. If the recorded temperature is 130°C after 1 minute, then the time constant of thermometer (in min) is (A) 1.98 (B) 1.35
(C) 1.26
(D) 1.09
Q 9. Air with wet bulb temperature tw1 is passed through an adiabetic cooler from which it emerges with wet bulb temperature tw2.Then (B)
a.) tw1=tw2
b.)tw2 > tw1
c.)tw2 < tw1
Q 10. A thermosyphon works on the principle of ____________ (a) (b) (c) (d)
d,)tw2 >= tw1
gradient.
Pressure Temperature Density Chemical potential
Q 11. For identical tube pitch and flow rates in a STHE , the appropriate order of tube layouts of shellside heat transfer coefficient and pressure drop are: (a) (b) (c) (d)
30° = 45° = 60° = 90° 30° > 45° > 60° > 90° 90° > 60° > 45° > 30° (30° = 60°) < (45° = 90°)
Q 12. A cascade control system for pressure control is shown in the figure. The pressure transmitter has the range of 0 to 6 bar and the flow transmitter range is 0 to 81 nm 3/h. The normal flow rate through the valve is 32.4 nm3/h corresponding to the value of set point for pressure = 1 bar and to give the flow, the valve must be 40% opened. The control valve has linear characteristics and is fail to open.
The types of action of two controllers are: (A) Direct acting for pressure control and direct acting for flow control. (B) Indirect acting for pressure control and indirect acting for flow control. (C) Direct acting for pressure control and indirect acting for flow control. (D) Indirect acting for pressure control and direct acting for flow control.
Q 13. An equi-molar mixture of four hydrocarbons (1,2,3,4) is to be separated into high purity individual components using a sequence of simple distillation colums (one overhead and one bottom stream). Four possible schemes are shown.
Component
Ki
1
6
2
3
3
2.5
4
1.1
Using the Ki(=yi*/xi) values given,the optimal scheme is a.) P
b.)Q
c.)R
d.)S
Q 14. The commonly used solvent in supercritical extraction a.) Methyl-ethyl ketone b.) carbon tetrachloride c.) water
d.)Carbon –dioxide
Q 15. According to The Fenske equation, what will be the minimum number of plates required in a distillation column to separate an equimolar binary mixture of components A& B into an overhead fraction containing 99 mole% A and a bottoms fraction containing 98mole % B?(relative volatility is 2) a.) 5
b.) 9
c)12
d.)28
Q 16. The assumptions generally considered while studying heat transfer from a finned surface: (a) (b) (c) (d)
Cross-sectional area of film is very small, thereby reducing heat transfer. Film heat transfer coefficient remains constant Heat transfer is steady All of these
Q 17. In fluid catalytic cracker, the cracking reaction is ………………… and regeneration reaction is ……………………. a) b) c) d)
exothermic, exothermic exothermic, endothermic endothermic, exothermic endothermic, endothermic
Q 18. In sulphite process for paper manufacture, the ‘cooking liquor’ is ……………. a) b) c) d)
Magnesium bisulphite and sulphur dioxide in acid medium Magnesium sulphite and magnesium bicarbonate Sodium sulphite and magnesium sulphite Sodium sulphite, sodium bisulphite and sulphur dioxide
Q 19. Match the items mentioned in the left hand side column with the items mentioned in the right hand side column. (I)
Purge
(II)
Bypass
(III)
Unsteady state
(IV)
Recycle
(a) (I)-(a), (II)-(b), (III)-(c), (IV)-(d) (b) (I)-(c), (II)- (b), (III)- (d), (IV)- (a)
(a) A part of the product stream is sent back for reprocessing (b) A part of the reactant stream that does not undergo the processing but joins the processing stream (c) The entire stream or a part of it is let out of the processing zone due to build- up of a non-reacting components beyond a permissible level in it. (d) The process parameters change with time. (c) (I)-(b), (II)- (a), (III)- (c), (IV)- (d) (d) (I)-(c), (II)- (a), (III)- (b), (IV)- (d)
Q 20. Biodiesel is obtained from (a) Atmospheric distillation of crude petroleum (b) Catalytic cracking of atmospheric residue obtained by atmospheric distillation of crude petroleum (c) Hydro cracking of crude petroleum (d) Catalytic transesterifications of triglycerides. Q 21. An arbitrary scale °Brix is developed for the sugar industry. This scale is graduated in such a way that
(a) 1° Brix= 1° API (b) 1° Brix= 1° Baume
(c) 1° Brix = 1° Twaddell (d) 1° Brix= 1 wt% sugar in solution
Q 22. Which of the following is not em ployed in manufacture of linear polyvinyl chloride? a) b) c) d)
Emulsion polymerization Suspension polymerization Addition polymerization Condensation polymerization
Q 23. Pair the following industrial processes in group I with the catalysts in group II: Group I P. oxidation of o-xylene to phthalic anhydride Q. oxidation of ethanol to acetaldehyde R. oxidation of ammonia to oxides of nitrogen a) b) c) d)
Group II 1. V2O5 2. Pd 3. Ag 4. Pt
P-1, Q-3, R-4 P-2, Q-1, R-4 P-4, Q-3, R-1 P-1, Q-3, R-2
Q 24. Which of the following is true for virial equation of state? (a) (b) (c) (d)
Virial coefficients are universal constant Virial coefficient B represent three body temperature Virial coefficients are functions of temperature only For some gases, Virial equation and ideal gas equation are the same
Q 25. At the inversion point, Joule Thompson coefficient is (a) Positive
(b) negative
(c) zero
(d) infinity
Q 26. 2000 cm3 of a solution consisting of 30 mol% methanol and 70 mol% water at 250C is to be prepared by mixing pure methanol and pure water at 250C. Partial molar volumes for methanol and water in a 30 mol% methanol solution and their pure species molar volumes, both at 250C are: Methanol (1) Water (2)
V1’ = 38.632 cm3/mol V1 = 40.727 cm3/mol V2’ = 17.765 cm3/mol
V2 = 18.068 cm3/mol
Total volumes of pure methanol and pure water at 250C in cm3required are (a) 1000, 1000
(b) 600, 1400
(c) 1053, 1017
(d) 1017, 1053
Q 27. Match the appropriate pairs from Group I and Group II: Group I P. carbon disulphide Q. caprolactum R. gypsum a) P-4, Q-2, R-3 b) P-2, Q-1, R-3 c) P-3, Q-1, R-4 d) P-4, Q-1, R-3
Group II 1. Nylon-6 2. Nylon-66 3. Phosphoric acid 4. Viscose rayon
Q 28. Match the items in Group I with the ones in Group II: Group I P. black liqour Q. activated silica alumina R. press mud
a) b) c) d)
Group II 1. petroleum refining 2. sugar factory
P-1, R-2 P-2, Q-1 Q-1, R-2 Q-2, R-1
Q 29 . Which of the following process sequences is used in the production of synthesis gas? a) b) c) d)
Desulphurzationsteam reforminghot K2CO3 cycle Steam reformingdesulphurization hot K2CO3 cycle hot K2CO3 cyclesteam reformingdesulphurization hot K2CO3 cycledesulphurizationsteam reforming
Q 30. Lewis-Randall rule is (a) (b) (c) (d)
applicable for a species whose mole fraction approaches unity applicable for a species whose mole fraction approaches zero applicable in standard state for gases, liquids and solids used to calculate the activity coefficient of species
Q 31. The higher heating value of a fuel is the standard heat of combustion at 250C with (a) …… as the product; the lower heating value is the standard heat of combustion at 250C with (b)….. as the product (a) (b) (c) (d)
liquid water, liquid water water vapor, water vapor liquid water, water vapor water vapor, liquid vapor
Q 32. The product of Reynolds number and Prandtl number is called (a) Rayleigh number (b) Peclet number (c) Stanton number (d) Graetz number Q 33. Which of the following is true when an unsaturated air-water vapor mixture is cooled at constant pressure without contact with liquid water (a) (b) (c) (d)
Relative humidity increases and percentage humidity remains constant Relative humidity and percentage humidity decreases Relative humidity remains constant and percentage humidity increases Relative humidity and percentage humidity increases
Q 34. The rate constant of a chemical reaction increases 100 times when the temperature is increased from 400 to 500K. Assuming transition state theory is valid, the value of E/R is (a) 0.016
(b) 1328
(c) 8764 (d) 0.0023
Q 35. The coefficient of x2 in the Taylor’s series of cos 2x about 0 is (a) 2
(b) 0
(c) 1
(d) -1
Q 36. The velocity distribution in turbulent flow in a pipe is given by u/umax = (y/R)1/n where y is the distance from wall and R is the pipe radius. The ratio of average velocity to maximum velocity is (a) (b) (c) (d)
2n(n+2)/(n+1)(2n+1) 2n2/ (n+1)(2n+1) (n+1)(2n+1)/2n2 (n+1)(2n+1)/2n(n+2)
Q 37. Pure carbon is completely burnt in oxygen. The flue gas analysis is 60% CO2, 30% CO and 10% O2. The percent excess oxygen used is (a) 13.33
(b) 11.11
(c) -5.55 (d) 5.55
Q 38. The eigen values of a matrix [A] are 1,-2,3, then the eigen values of [A]2-2[A]+3[I] are (a) 2,11,16
(b) -1,8,3
(c) 3,3,3
(d) 3,3,13
Q 39. The system of equations 2x+4y= 10 5x+10y = 25 (a) (b) (c) (d)
Has no unique solution Has only one solution Has only two solutions Has infinite solutions
Q 40. Boundary layer separation is characterized by one of the conditions given below , where Re is the Reynolds number for the flow. Select the appropriate conditions (a) (b) (c) (d)
Re<<1, accelerating flow Re>>1, accelerating flow Re<<1, decelerating flow Re>>1, decelerating flow
Q 41. A 0.5 m high bed made up of a 1mm diameter glass spheres (density = 2500 kg/m3) is to be fluidized by water (density= 1000 kg/m 3). If at the point of incipient fluidization, the bed voidage is 40%, the pressure drop across the bed is (a) 4.4 kPa
(b) 2.94 kPa
(c) 3.7 kPa
(d) N.O.T
Q 42. Consider the following statements: 1. Priming is necessary in a centrifugal pump but not in reciprocating pump 2. For a centrifugal pump, the discharge varies inversely as the speed 3. The operating point of a pump installed in a pipe-line is decided by the speed of the pump. Which of the statements given above is/are correct ? (a) 1 only
(b) 2only
(c) 2 and 3
(d) 1,2 and 3
Q 43. Consider the following, which of the following statement is correct ? 1. An isotherm of an enthalpy- concentration diagram is a st raight line for an ideal solution 2. An isotherm on an enthalpy-concentration diagram is a curve for an ideal solution 3. A solution formed by adiabatic mixing of two solutions is represented by a point lying on a straight line connecting the points that represent the initial solutions. (a) 1 and 2 (b) 2 and 3 (c) 1 and 3 (d) 1,2 and 3 Q 44. For a phase margin of 300, the phase shift at a frequency for which amplitude ratio is unity is (a) (b) (c) (d)
1500 -1500 -2100 2100
Q 45. Match the non-viable particulates in the atmosphere given in the left hand column with the appropriate description given in right hand column (a) Mist
(I)
(b) Smoke
(II)
(c) Fume (III) (d) dust (IV) (a) (a)-(i), (b)- (ii), (c)- (iii), (d)- (iv) (b) (a)-(iv), (b)- (iii), (c)- (ii), (d)- (i) (c) (a)-(iv), (b)- (i), (c)- (iii), (d)- (ii) (d) (a)-(iii), (b)- (i), (c)- (iv), (d)- (ii)
Very small soot particles produced by burning and combustion of organic matter Fine particles produced during crushing, grinding and attrition of solid materials Produced by particles of spray liquids condensed vapors
Q 46. The Euler’s equation of motion (a) (b) (c) (d)
Can be derived from the Navier-Stokes e quation Is a statement of energy balance Is a preliminary step to derive the Bernoulli’s equation Cannot be applied to fluid at rest
Q 47. In the design of continuous distillation column for single feed of binary mixture the slope of the operating line for the enriching section depends on (a) (b) (c) (d)
Reflux ratio Reflux ratio and mole fraction of more volatile component in distillate Mole fraction of more volatile component in distillate and q-value of feed q-vale of feed and reflux ratio
Q 48. Which one of the following is not a solution of the differential equation d2y/dx2 +y =1 ?
(A) y=1
(B) y =1+ cos x
(C) y = 1 + sin x
(D) y =2 +sin x + cos x
Q 49. A species (A) reacts on a solid catalyst to produce R and S as follows : 1)
A
→
R
r R = k 1 CA2
2)
A
→
S
r S = k 1 CA2
Assume film resistance to mass transfer is negligible . The ratio of instantaneous fractional yield of R in the presence of pore diffusion to that in the absence of pore diffusion is
(A) 1
(B) >1
(C) <1
(D) 0
Q 50. In a box containing 100 bulbs, 10 are defective. The probability that out of a sample of 5 bulbs, none is defective, (a) 5/95
(b) 5/90
(c)
90
C5/100C5 (d) N.O.T.
Q 51. The integrating factor for the differential equation (cos2x)dy/dx + y = tanx, is (a) etan x
(b) cos 2x
(c) e- tan x
(d) sin 2x
Q 52. The value of curl[grad (f)], where f= 2x2 – 3y2 + 4z2, is (a) 4x-6y+8z
(b) 4xi – 6yj+ 8zk
(c) 0
(d) 3
Q 53. An electrically heated element is submerged in a pool of water at its saturation temperature. As the temperature of the element inc reases, the maximum heat transfer coefficient is observed (a) In the free convection regime (b) Between the nucleate boiling and partial nucleate boiling mixed with unstable film boiling regimes (c) In the incipient nucleate boiling regime (d) In the stable film boiling regime without significant radiation effects Q 54. Match the items in Group I with those in group II Group I (P) Porous catalyst (Q) Parallel reaction (R) Non-ideal tubular reactor (S) Gas-solid non-catalytic reaction (a) (b) (c) (d)
Group II (I) Selectivity (II) Shrinking core model (III) Thiele modulus (IV) Dispersion number
P-3, Q- 1, R-4, S-2 P-1, Q- 3, R-2, S-4 P-1, Q- 4, R-2, S-3 P-3, Q- 4, R-1, S-2
Q 55. The fugacity coefficient of species i in solution (a) Has the dimension of concentration (b) Has the dimension of pressure (c) Has the dimension of energy (d) None of these Q 56. Consider the following statements sub-cooling in the condenser of a refrigeration system is advisable when 1. 2. 3. 4.
Expansion valve is at a higher elevation than condenser There is a large pressure drop in the connecting condenser to the expansion valve The refrigeration effect is to be increased The compressor work is to be reduced
Which of the following statement is true (a) (b) (c) (d)
1 and 2 1,3 and 4 2,3 and 4 1,2 and 3
Q 57. Phase rule for finding the degree of freedom is F= C -P-R+2, Here 2 stands for (a) Temperature and pressure variables of the system (b) Two reacting components (Since at least two reactants are required for the reaction to occur) (c) Two dependent equations (e.g. a component balance and the overall mass balance ) (d) Temperature and the equation y1+y2+ …… = 1 Q 58. Which one of the following statements is true? (a) Heat can be fully converted into work (b) Work cannot be fully converted into heat (c) The efficiency of a heat engine increases as the temperature of the heat source is increased while keeping the temperature of the h eat sink fixed (d) Throttling process is an isentropic process Q 59. Power number is proportional to the ratio of (a) Drag force acting on a unit area of impeller to the inertial stress (b) Gravity force acting on a unit area of the impeller to the inertial stress (c) The inertial stress to the gravitational force per unit area a cting on the fluid (d) N.O.T. Q 60. Pick out the wrong statement (a) More commonly used jaw crusher between dodge jaw crusher and blake jaw crusher is the later one (b) There are only four methods namely compression, impact, attrition and cutting, which the size r eduction equipment’s employ (c) Cutting machines mainly employ attrition for size reduction of solids (d) Operating principles of dodge and blake jaw crusher are combined in the working of universal jaw crusher Q 61. Fibrous material is broken by (a) (b) (c) (d)
Roll crusher Squirrel cage disintegrator Ball mill Tube mill
Q 62. Crushing efficiency is the ratio of the (a) (b) (c) (d)
Energy absorbed by the solid to that fed to the machine Energy fed to the machine to the surface energy created by crushing Energy absorbed by the solid to the surface energy created by crushing Surface energy created by crushing to the energy absorbed by the solid
Q 63. Sticky materials are transported by (a) (b) (c) (d)
Apron conveyor Screw conveyor Belt conveyor Hydraulic conveyor
Q 64. A saturated solution at 300C contains 5 mol of solute (M.W. = 50 kg/mol) per kg of solvent (M.W. = 20kg/ kmol) The solubility at 1000C is 10 moles of the solute per kg of the solvent. If 10 kg of the original solution is heated to 1000C, then the weight of the addition solute that can be dissolved in it, is (a) 0.25 kg
(b) 1 kg (c) 2 kg
(d) 3.34 kg
Q 65. What is the degree freedom of water at its triple point a) 1 b) 2 c) 0 d) 3
