Frequently Asked Question_chemical_final _24 Sep 18 .pdf

MMUP Chemical Engineering Frequently Asked Questions # 1 (120 Minutes)

1

Question # 01 The figure shows an enthalpy concentration chart for water. The heat evolved (Btu) when 50lb of water is mixed with 100 lb of sulfuric acid at 77F and with a final solution temperature of 77F is: Select one: A. B. C. D.

2750 16,000 18,750 21,500

Ans: D 2

Answer #1

3

Answer# 1

4

Question # 02

An Engineer is offered some additional gifts and services in exchange for using superior materials on a remodeling project. This was not detailed in the contract. He should A. B. C. D.

Take the offer and use the special materials Reject the offer Ask her boss which of the gifts to accept Accept the gifts but use the materials specified in the contract in order to retain neutrality

Ans: B 5

Question # 03

Transition from laminar to turbulent zone in free convection heat transfer is governed by the critical value of A. B. C. D.

Grashoff number. Grashoff number & Reynolds number. Reynolds number. Grashoff number & Prandtl number.

Ans: D 6

2 Minutes

Question # 04 An organic compound is produced in a vented, stirred steel reactor whose temperature is bounded by evaporation of hexane solvent(atmospheric boiling point is 156F). The reactor is protected by a relief valve sized for an elementary first-order reaction occurring in the vessel. The reactor is normally charged around 7.00am and the reaction is completed by mid afternoon. One day the reactor did not get charged until 1.00pm and the operator left it run it overnight, thinking the reaction was nearly completed. Before leaving at 7.00pm, the operator closed the vent valve to prevent excessive solvent loss. At 8.00pm, the reactor exploded. The most likely cause of the explosion was excessive reactor pressure because: A. B.

C. D.

The reaction was actually autocatalytic, so that increasing product concentration caused a rapid rate increase near the end of reaction. Heat generated by the stirrer increased the temperature enough to raise the hexane vapor pressure The solvent level in the charge was too low causing the concentration and thus the rate to be higher than greater than normal The first-order reaction rate constant was actually higher than that used to size the relief valve

Ans: B 7

Question # 05

The corrosion allowance, typically 0.125 In. for carbon steel and 0.065 In. for stainless steel, is added to the calculated material thickness to arrive at the final plate thickness that will be used in the design of the equipment. The type of corrosion against which this allowance is used is : A. B. C. D.

Pitting Galvanic corrosion Uniform corrosion attack on the metal surface Crevice corrosion

Ans: C 8

Question # 06

In condensers used in thermal power plants, steam is normally used in shell side and cooling water on the tube side, because of the reason that A. Compared to the mass flow rate of cooling water, the rate of condensation of steam is invariably smaller. B. Maintaining vacuum on tube side is more difficult than that on the shell side. C. Water velocity can be increased conveniently to increase the overall heat transfer co-efficient because of its lower specific volume compared to steam. D. Condenser can act as a storage unit for condensed steam.

Ans: C 9

Question # 07 A catalytic process for the removal of SO2 from flue gas by reducing the SO2 to elemental sulfur using methane has been tested. The desired reaction is:

10

Question # 07 Contd…..

In order to enhance the rate of the desired forward reaction relative to that of the undesired side reaction, which of the following strategies should be adopted? A. Increase both the reaction temperature and the concentration of SO2 in the feed. B. Increase the reaction temperature and decrease the concentration of SO2 in the feed C. Decrease the reaction temperature and increase the concentration of SO2 in the feed D. Decrease both the reaction temperature and concentration of SO2 in the feed

Ans: B 11

Question #8 The first step of scope definition is to: A) Analyze the strategic plan B) Analyze the current budget plan C) Meet with team members D) Select team members E) Define the major objectives to meet the customer’s needs

Ans: E 12

Question #9 Sudden fall of atmospheric pressure by a large amount is an indication of the A) Rain B) Cold wave C) Storm D) Fair weather

Ans: C 13

Question # 10 Sustainable development involves :A. Larger buildings using stronger design and materials. B. Developing better transportation by building more roads. C. Reducing consumption, increasing efficiency and using renewable energies. D. Using all the resources at maximum rates.

Ans: C 14

Question # 11 Benzene, Toluene and Xylene can be separated by distillation. When 652kg of a mixture containing 45% Benzene, 32% Toluene and 23% Xylene is separated in to three streams. Stream A contains 98.9% Benzene and 1.1% Toluene; Stream B contains 95.8% Toluene, 2.7% Benzene and 1.5% Xylene; and Stream C contains 93.6% Xylene and 6.4% Toluene. Find the mass (kg) of stream A? A. B. C. D.

157 204 266 291

Ans: D 15

Answer # 11

16

Question # 12 Which of the following characteristics is not a typical of a project manager? A. B. C. D. E.

Managing a temporary activity Possesses in-depth technical knowledge Managing a non-repetitive activity Manages independently of the formal organization Provides a direct link to the customer

Ans: B 17

Question # 13 The composition of a natural gas is 90% and 10% N2 by volume. It is burned under a boiler and the CO2 is scrubbed out from the cooled dry flue gases for the production of Dry ice. The Orsat analysis of the gas leaving the scrubber shows 1.1% CO2, 5% O2 and 93.9%N2. A schematic of the process is shown below:

Methane burns according to the following reaction: CH4+2O2 CO2+2H2O In this process, 25% excess air is used. Assume complete combustion of the methane in the boiler furnace. The percentage CO2 absorbed in the scrubber is: 18

Question # 13 Contd…. A. B. C. D.

95.2 88.9 76.4 85.7

Ans: B 19

Answer # 13

20

Question # 14 A liquid is pumped from a horizontal tank and delivered to column elsewhere as shown in figure: The other data ae as follows: Operating pressure= 0 psig Design Pressure= 50 psig Operating temperature = 181 F Vapor pressure at normal pumping temperature= 14.7psia Specific gravity of liquid=0.81 Discharge pressure = 190 psig

The total dynamic head of Pump(ft) is most nearly A. 400 B. 450 C. 479 D. 523

Ans: D

21

Answer # 15

22

Question # 16 If 16.71 kg of water is evaporated from a vat containing 123.2kg of a 12.3% brine and a 2.37kg of pure dry salt is added. What percentage of salt zones the resulting brine contain? A. B. C. D.

11.4% 12.5% 14.5% 16.1%

Ans: D 23

Answer #16

24

Question # 17 A carnot engine that received heat at a certain temperature develops 2 hp and rejects 7500 Btuh to a sink at 60F. The heat source temperature (QP) of the carnot engine is near to: A. B. C. D.

400 450 413 500

Ans: C 25

Question # 18 Which of the following commonly used condenser tube materials has the lowest thermal conductivity? A. B. C. D.

Admirability brass. Stainless steel. Aluminium brass. Titanium.

Ans: B 26

Question # 19 Consider the following: I. 8ft diameter x4oft tall distillation column II. 8ft x8ftx6ft deep cooling tower basin III. 8ftx8ftx10ft tall electrical room IV. 3ftdiameter x 6ft tall boiler steam drum Which of the above are considered to be confined spaces and require special entry procedures?

A. B. C. D.

I, II only I,II,IV only I, IV only II, IV only

Ans: B

1&2&4 as all tanks have height more than 5 feet 27

Question # 20 Your pass has just approved the initiation of a project to celebrate Qatar National Day. Sadia has been assigned the project manager by the Boss. Sadia’s very first task should be to: A. B. C. D. E.

Establish the reporting process to the boss Work on the project scope Make a report on required cost for the project Develop project charter to do the project Ask the boss as to how many team members would be allowed in the project

Ans: B 28

Question # 21 The __________ of a double acting reciprocating pump as compared to the single acting pump will be almost double. A. B. C. D.

Flow output Head developed Overall efficiency Weight

Ans: A 29

Question # 22 The most suitable material of construction for a sewer to carry sewage under high pressure is A. B. C. D.

Asbestos cement Steel Cement concrete Stoneware

Ans: B 30

Question # 23 Fire in fuel gas pipelines is extinguished most effectively by

A. B. C. D.

Spraying water. Blanketting the area with nitrogen atmosphere. Fire fighting foam. None of these.

Ans: B 31

Question # 24 An ideal gas at a temperature of 25 degree is contained in a cylinder filled with a movable piston. The cylinder is placed in boiled water with the piston held in position until it contents rise to 100 degrees. During this process 2kcal of heat is transferred to the gas. After the contents reach 100 degrees the piston is released and the gas does work equal to 100J. The final gas temperature is 100 Degrees. The total heat (J) transferred to the gas during the two steps is: A. B. C. D.

8170 8270 8370 8470

Ans: C 32

Question # 25 A liquid is stored in a large diameter tank that is maintained at 190F. The tank constructed of 1.5 in. –thick carbon steel plate (k=23Btu/hr-ft-F). The convective heat transfer coefficients are: Inside of tank h=30 Btu/(hr-ft2-F); Exterior of tank: h=10 Btu/(hrft2-F) The cold design air temperature is -20F. For a fouled interior tank wall (R=0.01 hr-ft2-F/Btu), the heat loss flux (Btu/(hr-ft2) is most nearly

A. B. C. D.

1,140 1,420 1470 1510

Ans: B 33

Answer# 25

34

Question # 26 Superheating of steam is done at constant

A. B. C. D.

enthalpy entropy pressure volume

Ans: C 35

Question # 27 Dry saturated steam can be converted into superheated steam by

A. B. C. D.

increasing its cross-sectional area of flow. passing it through a pressure reducing valve. forcing it downwards through a vertical tube. none of these

Ans: B 36

Question # 28 A thermopane window is one in which two pieces of glass are stagnant air layer. The following data apply: Inside and outside convection coefficients 1 Btu/(hr-ft2-F) Thermal conductivity of air 0. 5 Btu/(hr-ft2-F) Thermal conductivity of air 0. 015 Btu/(hr-ft2-F) Glass Thickness 0.25 in. Air gap for thermopane 0.25 in. The ratio of the heat flux for a thermopane to that for a single glass pane is:

A. B. C. D.

0.13 0.59 0.98 1.7

Ans: B 37

Answer # 28

38

Question # 29 A heterogeneous catalytic chemical reaction between gaseous reactants A and B in the presence of a solid catalyst and with the overall stoichiometry of A+B -- products has the following overall equation:dPA/dt= kPAPB/(1+KPA). Here k and K are constants, and PA and PB represent the partial pressures of reactants A and B, in the gaseous phase. One can conclude from this rate expression that this chemical reaction occurs between:

A. Gaseous reactant B and absorbed reactant A on the catalyst surface B. Gaseous reactant A and absorbed reactant B on the catalyst surface C. Reactants A and B , both absorbed on the catalyst surface D. Reactants A and B exclusively in the gaseous phase Ans: C 39

Question # 30 Project scope management includes

A. B. C. D.

Scope planning and scope verification Scope definition and scope control Scope clarification and scope breakdown structure All of the above

Ans: D 40

Question # 31 Carnot cycle is also termed as the constant __________ cycle in thermodynamics.

A. B. C. D.

entropy pressure volume heat

Ans: D 41

Question # 32 When an isolated thermodynamic system executes a process,

A. B. C. D.

work is done. heat transfer takes place. mass flow occurs across the boundary of the system. no chemical reaction takes place within the system.

Ans: D 42

Question # 33 The function of a nozzle provided in steam turbine is to

A. B. C. D.

throttle down (i.e., reduce) the pressure of steam. convert internal energy into kinetic energy. increase the velocity of steam. all (a), (b) & (c).

Ans: D 43

Question # 34 Feed check valve is used in steam boilers to

A. check the water level in the boiler. B. check the feed water flow rate. C. feed high pressure water to boiler and guard against its backflow through it. D. none of these.

Ans: C 44

Question # 35 Aluminium sulfate is manufactured by treating crushed bauxite ore with sulfuric acid. The ore contains 55.4 Al203, sulfuric acid is 77.7H2So4. The reaction of Al203 with H2SO4 can be represented by the following equation: Al2O3+2H2SO4--- Al2(SO4) 3 H2O The molecular weights of the compounds are as follows: Component Molecular wt. AlsO3 101.96 H2SO4 98.08 Al2(SO4)3 342.14 H2O 18.03 In one batch, 2160 lb of bauxite ore were treated with 5020 lb of sulfuric acid to obtain a final solution containing 3600 lb of aluminium sulfate. The percent conversion of Al2O3 is:

A. B. C. D.

67.4 89.7 72.3 96.2

Ans: A 45

Question # 36 Which of the following would not be classified as an opportunity to do a project?

A. B. C. D. E.

Increasing product demand Emerging markets Lot of employees Favorable international exchange rates None of these are organizational opportunities

Ans: C 46

Question # 37 Consider system A at uniform temperature t and system B at another uniform temperature T (t > T). Let the two systems be brought into contact and be thermally insulated from their surroundings but not from each other. Energy will flow from system A to system B because of

a) Temperature difference b) Energy difference c) Mass difference d) Volumetric difference

Ans: D 47

Question # 38 An oil cooler in a high performance engine has an outside surface area 0.12 m2 and a surface temperature of 65 degree Celsius. At any intermediate time air moves over the surface of the cooler at a temperature of 30 degree Celsius and gives rise to a surface coefficient equal to 45.4 W/ m 2 K. Find out the heat transfer rate?

A. B. C. D.

238.43 W 190.68 W 543.67 W 675.98 W

Ans: D 48

Question # 39 TQM stands for

A. B. C. D.

Tool Quality Management Test Quality Manager Total Quality Management Total Quality manager

Ans: C 49

Question # 40 Activity on Arrow needs to use dummy activities to avoid precedence problem that can happen due to:

A. B. C. D. E. F.

Parallel activities Critical path activities Burst activities Merge activities Independent activities None of the above

Ans: D 50

Question # 41 The rate equation used to describe the mechanism of convection is called Newton’s law of cooling. So rate of heat flow by convection doesn’t depend on

A. B. C. D.

Convective heat transfer coefficient Surface area through which heat flows Time Temperature potential difference

Ans: C 51

Question # 42 Which of the following is an example of forced convection?

A. B. C. D.

Chilling effect of cold wind on a warm body Flow of water in condenser tubes Cooling of billets in the atmosphere Heat exchange on cold and warm pipes

Ans: B 52

Question # 43 In a chemical process, superheated steam at 250 psia and 8oo F expands through a reversible well insulated turbo-expander to 2.89 psia. The shaft work produced is the enthalpy difference between the inlet and outlet streams. The shaft work produced by the turbo-expander (Btu/lb) in the process is : Useful Info: At 250 psia and 800F ; h in =1,422.75 Btu/lb, S in = 1.7398 Btu(lb-R) Outlet saturated steam at 2.89 psia: hv = 1,122.75 Btu/lb Sv = 1.8894 Btu(lb-R) hl= 107.89 Btu/lb, Sl= 0.1984 Btu(lb-R)

A. B. C. D.

10 150 300 400 Ans: C 53

Question # 44 A pipeline from a refinery in Masaieed to a tank farm in Rayyan, carries four different brands and three different grades of gasoline on an alternating schedule. To minimize cross-contamination of grades and /or brands during transit through the pipeline, the flow in the pipeline should be:

A. B. C. D.

Laminar Transitional Minimally turbulent Highly turbulent

Ans: D 54

Question # 45 A hot plate of 15 cm2 area maintained at 200 degree celsius is exposed to still air at 30 degree Celsius temperature. When the smaller side of the plate is held vertical, convective heat transfer rate is 15 per cent higher than bigger side of the plate is held vertical. Find size of the plate. The appropriate correlation for the convection coefficient is Nu = 0.60 (Gr Pr) 0.25

A. B. C. D.

l = 5.123 cm and b = 2.928 cm l = 6.123 cm and b = 3.928 cm l = 7.123 cm and b = 4.928 cm l = 8.123 cm and b = 5.928 cm

Ans: A

t f = 200 + 30/2 = 115 degree celsius. Pr = µ c/k, Gr = b3 p 2 β g d t/µ 2 and Nu = h b/k. 55

Question # 46 A horizontal heated plate at 200 degree Celsius and facing upwards has been placed in still air at 20 degree Celsius. If the plate measures 1.25 m by 1 m, make calculations for the heat loss by natural convection. The convective film coefficient for free convection is given by the following empirical relation, h = 0.32 (α) 0.25 W/m2 K Where α is the mean film temperature in degrees kelvin

A) 6006 W B) 5006 W C) 4006 W D) 3006 W

Ans: D

α = 273 + 200 + 20/2 = 383 degree Celsius. Therefore, rate of heat loss = h A d t = 3006 W. 56

Question # 47 Air at atmospheric pressure and 20 degree Celsius flows with 6 m/s velocity through main trunk duct of air conditioning system. The duct is rectangular in cross-section and measures 40 cm by 80 cm. Determine heat loss per meter length of duct corresponding to unit temperature difference. The relevant thermos-physical properties of air are, v = 15 * 10 -6 m 2/s, α = 7.7 * 10 -2 m2/hr, k = 0.026 W/m degree

A) 32.768 W B) 42.768 W C) 52.768 W D) 62.768 W

Q = h A d t, Area = 2 (a + b) (1) = 2.4 m2, h = 365.34 k/l. Ans: B 57

Question # 48 A liquid phase reaction of the first order with a reaction rate constant k=0.3min-1 is carried out in two CSTRs in series, each with a 750 gal volume. The feed rate is 15 ft3/m. The conversion attained will be: X=1 1 /(1+Da)n

A. B. C. D.

0.85 0.89 0.93 0.97

Ans: A 58

Question # 49 In the figure shown, the following curves for a pumping system are plotted : the HQ curve, the system curve and the efficiency curve For the flow rate through the piping given by the intersection point of the system and H-Q curves, the standard size motor that should be recommended

A. B. C. D.

3 hp 5 hp 7.5 hp 2.5 hp

Ans: C 59

Question # 50 Lube oil is cooled in the annulus of a double-pipe exchanger from 4500P to 3500P by crude oil flowing in the tube. The following properties of lube oil are at the caloric temperature Heat capacity, Cp=0.615 Btu/lb F, Viscosity µ= 3.05cP Thermal conductivity, k= 1.55 x10-6 Btu/S in F Prandtl number = Cp.µ/k

The value of the Prandtl number under these conditions is:

A. B. C. D.

12.2 57.4 28.3 67.7

Ans: A 60

Question # 51 Which of the following is an example of steady state heat transfer?

A) Boilers and turbines B) Cooling of I.C engine C) Chilling effect of cold wind on a warm body D) Electric bulb cools down by the surrounding atmosphere

Ans: D 61

Question # 52 Heat transfer takes place according to which law?

A) Newton’s law of cooling B) Second law of thermodynamics C) Newton’s second law of motion D) First law of thermodynamics

Ans: B 62

Question # 53 Heat transfer takes place in liquids and gases is essentially due to

a) Radiation b) Conduction c) Convection d) Conduction as well as convection

Ans: C 63

Question # 54 The composition of a natural gas is 90% and 10% N2 by volume. It is burned under a boiler and the CO2 is scrubbed out from the cooled dry flue gases for the production of Dry ice. The Orsat analysis of the gas leaving the scrubber shows 1.1% CO2, 5% O2 and 93.9%N2. A schematic of the process is shown below:

Methane burns according to the following reaction: CH4+2O2 CO2+2H2O In this process, 25% excess air is used. Assume complete combustion of the methane in the boiler furnace. The percentage CO2 absorbed in the scrubber is: 64

Question # 54 Contd…. A. B. C. D.

95.2 88.9 76.4 85.7

Ans: C 65

Question # 55 Engineers are :

A. Individuals who combine knowledge of science, mathematics, and economics to solve technical problems that confront society B. Individuals who study the laws of nature and generate new knowledge

Ans: A 66

Question # 56 During a cold winter season, a person prefers to sit near a fire. Which of the following modes of heat transfer provides him the maximum heat? a) Conduction from the fire b) If it is near the fire, convection sounds good c) Convection and radiation together d) Radiation will provide quick warmth

Ans: D 67

Question # 57 The appropriate rate equation for convective heat transfer between a surface and adjacent fluid is prescribed by A. B. C. D.

Newton’s first law Wein’s displacement law Kirchhoff’s law Newton’s law of cooling

Ans: D 68

Question # 58 Engineers are :

A. Individuals who combine knowledge of science, mathematics, and economics to solve technical problems that confront society B. Individuals who study the laws of nature and generate new knowledge

Ans: A 69

Question # 59 A binary mixture of tetrahydrofuran(THF) and isopropyl alcohol (IPA) is to be separated in to relatively pure streams of THF and IPA in a distillation column operating at atmospheric pressure. The column material balance is summarized in the table below For a stripping-section mortar L/V ratio of 1.40, the Vapor leaving the kettle reboiler has a flow rate (lb mole/hr) of:

A. B. C. D.

3.15 1.76 0.9 0.52

Ans: A 70

Question # 60 An ammonia-water system (essentially at its bubble point) is processed in a trayed stripping column with an external kettle boiler to recover the majority of the ammonia. A constant molal overflow simulation provides the following information: Overhead ammonia mole fraction 0.95 Bottoms ammonia mole fraction 0.01 Feed ammonia mole fraction 0.40 The reboiler boilup ratio (V/B) for these conditions is: A. B. C. D. E.

0.71 0.85 1.35 1.71 0.52

Ans: B 71

Question # 61 Heat transfer in a long, hollow cylinder which is maintained at uniform but different temperatures on its inner and outer surfaces may be assumed to be taking place in which direction?

A. B. C. D.

Axial only Unpredictable Radial only No heat transfer takes place

Ans: C 72

Question # 62 Propylene glycol is produced by the hydrolysis of propylene oxide(PO) in the liquid phase: CH3CHOCH2+H2O -CH3CHOHCH2OH This exothermic reaction occurs readily at room temperature when catalyzed by sulfuric acid. The feed is a stream of 24,000 kg/hr with the following Propylene oxide 10WT%, Sulfuric acid 1wt%, Water 89 wt% Other data are: Heat capacity of the reaction mixture 4.18kJ/(Kg.K) Heat of reaction -1459 KJ/Kg PO If an adiabatic reactor is used to achieve a fractional conversion of 0.8 for PO with a feed temperature of 20·C, the reactor exit temperature is A. B. C. D.

265 K 295 K 300 K ES=22 LS=24

Ans: A 73

Question # 63 Air enters a countercurrent dryer at a flow rate of 1,000 kg/s (dry basis) at 405K. The humidity of the entering air is 7.0 g moisture/kg dry air. The reference temperature is 298K. The following data are available Heat capacity of dry air 0.99 kJ/(kg.K) Heat capacity of water vapor 2.01 kJ/(kg.K) Heat capacity of liquid water 4.186kJ/(kg.k) Latent heat of vaporization of water at 298K 2,442 kj/kg The enthalpy of the incoming air (MJ/s) is: A. B. C. D.

107 124 401 424

Ans: D 74

Question # 64 Investigate the effect of following condition on the average value of heat transfer coefficient in flow through a tube Two fold increases in flow velocity by varying mass flow rate It may be presumed that there is no change in the temperature of the liquid and the tube wall, and that the flow through the tube is turbulent in character A. B. C. D.

64.1% decrease 64.1% increase 74.1%decrease 74.1% increases

Ans: D

h 2/h 1 = (V 2/V 1) 0.8 = .0741 = 74.1% 75

Question # 65 Find the early start of activity D for the project

A. B. C. D.

ES=12, LS=15 ES=13, LS=22 ES=19, LS=22 ES=22,LES=24

Ans: C 76

Question # 66 The main activity in project scope definition is to : A. B. C. D. E.

Set up the meeting on the project Analyze the current budget plan Meet with team members Select the team members Define the work break down structure

Ans: E 77

Question # 67 A heat treat steel plate measures 3 m by 1 m and is initially at 30 degree Celsius. It is cooled by blowing air parallel to 1 m edge at 9 km/hr. If the air is at 10 degree Celsius. Estimate the convection heat transfer from both sides of the plate A. B. C. D.

477.7 W 547.7 W 647.7 W 747.6 W

Q = h A d t, h = Nu k/d. Ans: D 78

Question # 68 A heat treat steel plate measures 3 m by 1 m and is initially at 30 degree Celsius. It is cooled by blowing air parallel to 1 m edge at 9 km/hr. If the air is at 10 degree Celsius. find the value of Reynolds number A. B. C. D.

166003 177003 188003 199003

Re = p V l/µ = 16603 Ans: A 79

Question # 69 A tank is maintained at 250 F using 50-psig saturated steam. The tank heat loss is 75,000 Btu/h and is compensated for by using a 1-in sch. 40 pipe worm heater. The following data apply: T steam(50psig)= 298 F Convective heat transfer coefficients Condensing steam h 1,200 Btu/(hr-ft2-F) Exterior of pipe to fluid h = 40 Btu/(hr-ft2-F) Pipe data Thermal conductivity 26 Btu/(hr-ft-F) Interior pipe diameter 1.049 in. Exterior pipe diameter 1.315 in. The length (ft) of pipe needed for the worm heater A. B. C. D.

86 120 145 168

Ans: C 80

Question # 70 The standard heats of formation of ammonia (NH3), Nitric oxide(NO) and water (H2O), all in the gaseous state are -11.05 and 21.60 and -57.80 kcal/g mole, respectively. The standard heat of reaction for the complete oxidation of ammonia with oxygen to nitric oxide abd water vapor (kj/mol) is: A. B. C. D.

-905 -226 -54 46

Ans: D 81

Question # 71

The corrosion allowance, typically 0.125 In. for carbon steel and 0.065 In. for stainless steel, is added to the calculated material thickness to arrive at the final plate thickness that will be used in the design of the equipment. The type of corrosion against which this allowance is used is : A. B. C. D.

Pitting Galvanic corrosion Uniform corrosion attack on the metal surface Crevice corrosion

Ans: C 82

Question # 72 The standard heats of formation of ammonia (NH3), Nitric oxide(NO) and water (H2O), all in the gaseous state are -11.05 and 21.60 and -57.80 kcal/g mole, respectively. The standard heat of reaction for the complete oxidation of ammonia with oxygen to nitric oxide abd water vapor (kj/mol) is: A. B. C. D.

-905 -226 -54 46

Ans: D 83

Question # 73 Air flows through a 10 cm internal diameter tube at the rate of 75 kg/hr. Measurements indicate that at a particular point in the tube, the pressure and temperature of air are 1.5 bar and 325 K whilst the tube wall temperature is 375 K. Find heat transfer rate from one meter length in the region of this point. The general non-dimensional correlation for turbulent flow in the tube is Nu = 0.023 (Re) 0.8 (Pr) 0.4, Where the fluid properties are evaluated at the bulk temperature

A. B. C. D.

147.35 W 157.35 W 167.35 W 177.35 W

Q = h A d t, where h = (Nu) (k)/l = 177.35 W. Ans: D 84

Question # 74 Air flows through a 10 cm internal diameter tube at the rate of 75 kg/hr. Measurements indicate that at a particular point in the tube, the pressure and temperature of air are 1.5 bar and 325 K whilst the tube wall temperature is 375 K. find the value of Nusselt number The general non-dimensional correlation for turbulent flow in the tube is Nu = 0.023 (Re) 0.8 (Pr) 0.4, Where the fluid properties are evaluated at the bulk temperature

A. B. C. D.

40.46 50.56 60.66 70.76

Nu = 0.023 (Re) 0.8 (Pr) 0.4 = 40.46 Ans: A 85

Question # 75

A carnot engine that received heat at a certain temperature develops 2 hp and rejects 7500 Btuh to a sink at 60F. The heat source temperature (QP) of the carnot engine is near to: A. B. C. D.

400 450 413 500

Ans:C 86

Answer # 75

87

Question # 76 Of the following four methods, the one that will actually increase the galvanic corrosion of a more active metal is: A. Using combination of two metals as close as possible in galvanic series B. Protective Oxide films C. Coupling two widely separated metals in the galvanic series D. Insulating the two metals from each other

Ans: C 88

Question # 77 Three tanks A,B & C, at different elevations are interconnected as shown in figure. The levels in the tanks are shown as is the level in the piezometric tube. Flow quantities are also indicated Under the above conditions, the flow Q1, Q2 & Q3 are related by A. Q1+Q2=Q3 B. Q1-Q2=Q3

Ans: A 89

Question # 78 Aluminium sulfate is manufactured by treating crushed bauxite ore with sulfuric acid. The ore contains 55.4 Al203, sulfuric acid is 77.7H2So4. The reaction of Al203 with H2SO4 can be represented by the following equation: Al2O3+2H2SO4--- Al2(SO4) 3 H2O The molecular weights of the compounds are as follows: Component Molecular wt. AlsO3 101.96 H2SO4 98.08 Al2(SO4)3 342.14 H2O 18.03 In one batch, 2160 lb of bauxite ore were treated with 5020 lb of sulfuric acid to obtain a final solution containing 3600 lb of aluminium sulfate. The percent conversion of Al2O3 is:

A. B. C. D.

67.4 89.7 72.3 96.2

Ans: A 90

Question # 79 TQM stands for

A. B. C. D.

Tool Quality Management Test Quality Manager Total Quality Management Total Quality manager

Ans: C 91

Question # 80 An ideal gas at a temperature of 25 degree is contained in a cylinder filled with a movable piston. The cylinder is placed in boiled water with the piston held in position until it contents rise to 100 degrees. During this process 2kcal of heat is transferred to the gas. After the contents reach 100 degrees the piston is released and the gas does work equal to 100J. The final gas temperature is 100 Degrees. The total heat (J) transferred to the gas during the two steps is: A. B. C. D.

8170 8270 8370 8470

Ans: C 92

Question # 81 Which of the following would not be classified as an opportunity to do a project?

A. B. C. D. E.

Increasing product demand Emerging markets Lot of employees Favorable international exchange rates None of these are organizational opportunities

Ans: C 93

Question # 82 Lube oil is cooled in the annulus of a double-pipe exchanger from 4500P to 3500P by crude oil flowing in the tube. The following properties of lube oil are at the caloric temperature Heat capacity, Cp=0.615 Btu/lb F, Viscosity µ= 3.05cP Thermal conductivity, k= 1.55 x10-6 Btu/S in F Prandtl number = Cp.µ/k

The value of the Prandtl number under these conditions is:

A. B. C. D.

12.2 57.4 28.3 67.7

Ans: A 94

Question # 83 The composition of a natural gas is 90% and 10% N2 by volume. It is burned under a boiler and the CO2 is scrubbed out from the cooled dry flue gases for the production of Dry ice. The Orsat analysis of the gas leaving the scrubber shows 1.1% CO2, 5% O2 and 93.9%N2. A schematic of the process is shown below:

Methane burns according to the following reaction: CH4+2O2 CO2+2H2O In this process, 25% excess air is used. Assume complete combustion of the methane in the boiler furnace. The percentage CO2 absorbed in the scrubber is: 95

Question # 83 Contd…. A. B. C. D.

95.2 88.9 76.4 85.7

Ans: C 96

THANK YOU ALL THE BEST

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