Chemical Engineering Review Questions[1]

8/2/2019 Chemical Engineering Review Questions[1]

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CHEMICAL ENGINEERING REVIEW QUESTIONS 1

CHEMICAL ENGINEERING REVIEW QUESTIONS

NO QUESTION A B C D

1 A valve that controls flow by means of a disk orwedge-shaped dam sliding at right angles to thedirection of flow and seating tightly in the valvebody is a

gate valve butterfly valve globe valve orifice

2 The friction factor for flow through a pipe withrelative roughness of 0.004 at a Reynold's No. of80,000 is approximately equal to

0.05 0.03 0.03 0.04

3 The equation that relates friction factor andReynold's No., f=64/Reynold's No. holds for

smooth pipes laminar and turbulentflow

turbulent flow only laminar flow only

4 Oil flows under laminar conditions inside a steamheated copper pipe. The overall heat transfercoefficient is approximately

equal to the heattransfer coefficientof the oil

the average betweenthe heat transfercoefficient of thesteam and that of oil

equal to the heattransfer coefficientequivalent to theresistance offered bythe pipe

equal to the heattransfer coefficient ofthe steam

5 In multi-stage liquid-liquid extraction with partiallymiscible solvents

the extraction mustbe done to form co-currently in order tominimize theextraction.

the minimum numberof stages occur whenthe operating lines areparallel.

the minimum number ofstages occur when thetie line coincides withan operating line.

the amount ofsolvent used must beenough to form 2phases.

6 The enrichment of the vapor steam as it passes

through the column in contact with the reflux duringdistillation is called

evaporation stripping rectification fractionation

7 The maximum number of plates for a givendistillation system is obtained at

variable reflux maximum reflux minimum reflux optimum reflux

8 The correct unit for the specific rate constant forthe reaction A--->B determined to be first order is

square liter/squaremol/min

square liter/squaremol/square min

mol/liter/min liter/mol/min

9 On one side of a heat exchanger where either acondensing vapor or a boiling liquid is present, thetemperature may be assumed to be constant. Indetermining the logarithmic mean temperaturedifference the direction of flow will have

large effect little effect no effect significant effect

10 For a cylinder where steady-state radial heattransfer takes place

the heat flux isconstant

maximum heattransfer rate occurs at

the surface

the heat transfer isconstant

the temperature isuniform throughout

the cylinder

11 A plate holding a pool of liquid from which rises avapor whose average composition is in equilibriumwith a liquid whose composition is the average ofthat of the liquid leaving the plate is called

separation plate theoretical plate transition plate bubble plate

12 Crystallization occurs in a solution that is concentrated unsaturated supersaturated saturated

13 Mass transfer in a flowing fluid may be correlatedby

Sherwood, Nusseltand Reynold's No

Peclet, Reynold's andSchimdt No

Sherwood, Reynold'sand Schimdt No

Prandtl, Schimdt andReynold's No

14 The ratio of the average diameter of the feed to theaverage diameter of the product is the

settling ratio discharge ratio reduction ratio classification ratio

15 The rate of formation of C for the reaction 2A + B ---> C is found to be rate = k(A)(B)

the rate offormation of C is

equal to the rate ofdisappearance of B

the order of reactio iszero

the value of k isindependent of the

initial concentrations ofA and B

the reaction cannotproceed

16 A device for increasing the velocity of a fluid insteady flow is a

nozzle vent orifice venturi

17 In steady-state backmix flow reactor, compositionis

not constantthroughout thereactor

constant throughoutthe reactor

a function of time not uniformthroughout thereactor and variesfrom time to time

18 The amount of money obtainable from the sale ofused property over and above any changersinvolved in removal and sale is called

net value salvage value book value market value


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19 In fractionation, an increase in reflux ratio increases thenumber oftheoretical plates

decreases the reboilerduty

increases the amount ofdistillate

increases thecondenser duty

20 In mass transfer where the solute in the gas phaseis very soluble in the liquid phase

the ratio of liquidphase resistance tothe overallresistance is closeto unity

the gas phaseresistance isapproximately equal tothe total resistance

the gas phaseresistance is negligible

the ratio of gasphase resistance toliquid resistance isapproximately zero

21 Heat transfer in turbulent flow may be describedthrough an empirical equation correlating

Nusselt, Stantonand Reynold's Nos

Nusselt, Prandtl andReynold's Nos

Peclet, Stanton andPrandtl Nos

Schimdt, Peclet andFriction Nos

22 Which of the following fittings exhibits the highestpressure drop for the same flow conditions?

90-degree longradius elbow

90-degree standardelbow

45-degree standardelbow

square-corner elbow

23 A chamber into which steam from a high pressureline can be bled during periods of low steamdemand from the power plant is called

switching bank vent compressor accumulator

24 Which one of the following pipes has the highestrelative roughness?

2" diameterWrought iron pipe

4" dia Wrought ironpipe

1" dia Drawn tubing 4" dia Riveted steelpipe

25 In steady-state heat transfer through a series ofmaterials with varying resistances, the heattransfer rate

decreases towardsthe direction of heattransfer

varies with the thermalconductivity of eachmaterial

through each material isinversely proportional tothe thickness of thematerial

is constantthroughout the seriesof materials

26 Reactions whereby reactants proceed alongseveral paths and give different products are

polymeric reactions reversible reactions parallel reactions consecutivereactions

27 Which one among the following materials has thebest insulating property?

window glass wood air concret

28 An operation where warm vapor mixture is cooledsuch as by contact with a liquid resulting incondensation and decreased humidity is

evaporation dehumidification humidification extraction

29 The pressure exerted on a plane parallel to thedirection of flow of a moving fluid is called

gauge pressure velocity pressure tangential pressure static pressure

30 For mass transfer to take place, there must be a phase change reaction component concentration gradient momentum gradient

31 Water vapor condenses at 1 atm on a tube whosesurface tmeperature is at 80 deg F. in analyzingthe heat transfer through the condensate film, it isbest to evaluate the liquid properties at

212 deg F 80 deg F 113 deg F 146 deg F

32 The diffusity of water in air at 100 deg F in

sq.cm./sec is

0.26 0.28 1.48 0.58

33 A fluid flowing at a rate of 25 cubic meters per hourinside a 60 mm I.D. pipe has an average velocity inmeter per sec equal to

5.90 2.50 1.50 0.60

34 An equimolar mixture of benzene and toluene issubjected to a single batch distillation. Distillation isdiscontinued when 60% of the benzene in the feedis distilled. At this instance the bottom productwhen analyzed shows benzene to be 36.4 mole%.In the distillate, the mole% of benzene is

66.60 58.10 33.40 54.40

35 When 32 kg of methane is burned completely thetheoretical oxygen required is

16 kg 64 kg 128 kg 32 kg

36 The standard heat of reaction for the production ofwater gas, in kcal/gmole, as given by the equation:C(s) + H2O(g) = CO(g) + H2(g) is

32.20 31.40 26.40 57.80

37 A rectangular duct 4 ft x 1.5 ft in cross sectioncarries conditioned air. In determining the pressuredrop through the duct the equivalent diameter in ftmay be used which in this case is

4.00 2.18 1.50 2.75

38 A gas decomposition reaction has an activationenergy of 245 kJ/mol. The rate of reaction can beaccelerated by using a platinum catalyst where theactivation energy for the resulting catalyzedreactions is lower at 136 kJ/mol. Using Arrhenius'law and assuming the frequency factor remains thesame the catalyzed reaction is faster than the

over 100,000 butless than a million

over 100 but less than200

over 20 million over 2 but less than3


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original reaction by a factor of

39 Water at 100 deg F is flowing through a straight 4-in Sch 40 pipe at a rate of 1.0 gal/min. The lengthof the pipe is 10 ft. The velocity at the center of thepipe in ft per sec is

0.04 0.05 0.05 0.03

40 A metallic rod 2 cm in diameter is used as aheating element. The thermal conductivity is 370J/sec.sq.m.degC. The surface temperature ismaintained at 200 deg C. For the center of the rodnot to exceed 500 deg C, the maximum volumetric

heat generation rate within the metallic rod in J/seccu.m. must be

4440000.00 5130000.00 6930000.00 2040000.00

41 This is a steady state temperature reached by asmall amount of liquid evaporating into a largeamount of unsaturated vapor-gas mixture.

wet-bulbtemperature

dew point saturation temperature dry-bulb temperature

42 Air, supplied at the rate of 1200 cfm to arefrigerated coil, has a relative humidity of 20%and dry bulb temperature of 150 deg F. The massflow of dry air entering per minute is

74.30 75.00 75.26 78.50

43 In adiabatic humidification, it is possible to maintainthe temperature of water constant since

according to thephase rule, thedegrees of freedomis 3

the system can be wellinsulated from thesurroundings

the temperature of theair can also bemaintained constant

increase in thehumidity of the air isinsignificant

44 An air-carbon tetrachloride vapor mixture at 100

deg F dry bulb and 60 deg F wet bulb is heateduntil the temperature reaches 180 deg F. the finalpercent relative humidity is about

0.10 0.05 0.02 0.01

45 The portion of water in the wet solid that cannot beremoved by the air in its contact is called

free moisture final moisture content equilibrium moisturecontent

critical moisturecontent

46 This type of drier is used for drying pasty materialssuch as wet filter cakes and lumpy solids

rotary drier flash drier tray drier freeze drier

47 In the constant-rate period, the rate of drying isestablished by

a balance of theheat requirementsfor evaporation andthe rate at whichheat reaches thesurface

the internal movementof moisture beneaththe surface of the solid

air flow perpendicular tothe surface of the solid

air flow parallel to thesolid surface

48 Unbound moisture in granular and porous solid

moves through the intertices of the solid by amechanism involving

desorption surface tension surface renewal moisture diffusivity

49 Wet solid is to be dried from 40% to 10% in 5hours under constant drying conditions. The criticalmoisture content is 20% and the equilibriummoisture content is 7%. All moisture contents areon dry basis. The time needed to dry from 15% to5% free moisture under the same drying conditionsis

0.542 hrs 1.846 hrs 2.129 hrs 3.42 hrs

50 If the rate of drying under constant dryingconditions with air at 140 deg F and absolutehumidity of 0.03 lb water per lb dry air of unknownmass of solid is given by R=0.5-exp(-60X) [in lbwater/hr-sqft], then the equilibrium moisture

content (db) of the material is

0.12 0.03 0.01 0.00

51 In drying at the falling rate period, the rate at whichmoisture is removed from the solid material

remains constant increases with time decreases with time no drying takes place

52 The major problem in diffusion is to promotediffusion of the solute out of the solid and into theliquid. The most effective way of doing this is

to reduce the solidto the smallest sizefeasible

to use counter currentoperation

to use cross flowevaporation

to use spraypercolators

53 A slurry flaked soybeans weighing 100 kg contains75 kg inert solids and 25 kg of solution 10 weight% oil and 90% wt solvent hexane. This slurry iscontacted with 100 kg pure hexane in a singlestage so that the value of retention for the outletunderflow is 1.5 kg of insoluble solid per kg solventin the adhering solution. The composition of

0.30 0.80 1.50 2.30


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underflow leaving the extraction stage in %wt oil is

54 Tung meal containing 55% oil is to be extracted atthe rate of 4000 lb per hour using n-hexanecontaining 5% oil as solvent. A countercurrentmultiple stage extraction system is to be used. Themeal retains 2 lb of solvent per pound of oil freemeal while the residual charge contain 0.11 lb oilper lb oil free meal while the product is composedof 15% oil. The theoretical number of ideal stagesis

3.00 4.00 5.00 6.00

55 The movement of molecules over a substantialdistance is associated with the transfer of heat by

convection conduction radiation all of A, B and C

56 The mode of heat transfer that can take place in avacuum is known as

convection conduction radiation all of A, B and C

57 The overall conductance for a composite materialin series is equal to the

sum of theindividualconductances

sum of the individualconductivities

inverse of the totalresistance

sum of the individualresistances

58 Film and drop are terms associated with boiling condensation evaporation all of A, B and C

59 A 6-in Sch 80 steel pipe is carrying glycerin at anaverage temperature of 100 deg F. The pipe isuninsulated, and the outside temperature is 30 degF. The inside film conductance is 1000 Btu/h-ft-degF while the outside film conductance is 3.0Btu/h-sq.ft.-degF. Determine the heat lost [Btu] per

minute from a 75-ft length of the pipe. Glycerine isflowing at 800 gpm.

99.95 415.70 451.70 475.10

60 An oak (k=0.096 Btu/h-ft -degF) door, 30 in wide,78 in high, and 2 in thick, has 9 glass (k=0.45Btu/h-ft-degF) windows, each 6 in by 8 in by 1/4 inthick. Determine the amount of heat lost [Btu] eachday with a surface-to-surface temperaturedifference of 80 deg F.

97.00 242.00 5800.00 139200.00

61 Determine the length needed for a simpleconcentric-tube, parallel flow heat exchanger totransfer heat from hot water to cold water at a rateof 900 W. The heat exchanger consists of twoType K copper (k=386 W/m-degC) tubes. Thesmaller tube has an inside diameter of 49.8 mm

and an outside diameter of 54.0 mm. Assume thatboth film coefficients are equal to 100 W/sq.m.-degC. The hot water enters at 90 degC and leavesat 50 degC, and the cold water enters at 10 degCand leaves at 40 degC.

185.5 m 11.02 m 5.51 m 4.14 m

62 A saturated solution containing 1500 kg ofpotassium chloride at 360 K is cooled in an opentank to 290K. If the specific gravity of the solutionis 1.2, the solubility of potassium chloride per 100parts of water is 53.55 at 360K and 34.5 at 290K,calculate the amount of crystals obtained assumingthat loss of water by evaporation is negligible.

4301 kg 1500 kg 966 kg 534 kg

63 An evaporator, working at atmospheric pressure, isto concentrate a solution from 5% to 20% solids at

the rate of 1.25 kg/s. The solution which has aspecific heat of 4.18 kJ/kg-K is fed to theevaporator at 295K and boils at 380K. Drysaturated steam at 240 kPa is fed to the calandriaand the condensate leaves at the temperature ofthe condensing steam. If the heat transfercoefficient is 2.3 kW/sq.m-K, what is the requiredarea of heat transfer surface. The latent heat ofvaporization maybe taken as the same as that ofwater.

55.8 sq.m. 58.5 sq.m. 85.8 sq.m. 88.5 sq.m.


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64 2.5 kg/s of a solution at 288K containing 10%dissolved solids is fed to a forward-feed doubleeffect evaporator operating at a pressure of 14 kPain the last effect. If the product is to consist of aliquid containing 50% by weight of dissolved solidsand dry saturated steam is fed to the steam coils,what should be the pressure of the steam? Thesurface in each effect is 50 sq.m. and thecoefficients for heat transfer in the f irst and secondeffects are 2.8 and 1.7 kW/sq.m.-K respectively.Assume that the concentrated solution exhibits aboiling point rise of 5 degK, that the latent heat hasa constant value of 2260 kJ/kg and that the specificheat of the liquid stream is constant at 3.75 kJ/kgK.

115 kPa 101.3 kPa 14 kPa zero gauge

65 An acetone-air mixture containing 0.015 molfraction of acetone has the mol fraction reduced to1% of this value by countercurrent absorption withwater in a packed tower. The gas flow-rate G is 1kg/sq.m-s of air and the water entering is 1.6kg/sq.m-s. For this system, Henry's law holds andYe=1.75x, where Ye is the mol f raction of acetonein the vapour in equilibrium with a mol fraction x inthe liquid. How many overall transfer units arerequired?

10.92 9.12 4.72 3.03

66 A still has a liquor composition of ortho-xylen 10%,

meta-xylene 65%, para-xylene 17%, benzene 4%,and ethylbenzene 4%. How many plates at totalreflux are required to give a product of 80% meta-xylene and 14% para-xylene? The data are givenas mole percent.

37.00 38.00 39.00 40.00

67 A mixture of alcohol and water with 0.45 molfraction of alcohol is to be continuously distilled in acolumn so as to give a top product of 0.825 molfraction alcohol and a liquor at the bottom with 0.05mol fraction alcohol. How many theoretical platesare required if the reflux ratio used is 3?

10.00 9.00 8.00 7.00

68 Prepared cottonseed meats containing 35%extractable oil are fed to a continuouscountercurrent extractor of the intermittent

drainage type using hexane as solvent. Theextractor consists of ten sections, the sectionefficiency being 50%. The entrainment, assumedconstant, is 1 kg solution/kg solids. What will bethe oil concentration in the outflowing solvent if theextractable oil content in the meats is to bereduced to 0.5% by weight?

72.20 28.70 27.80 22.70

69 0.4 kg/s of dry seashore sand, containing 1% byweight of salt, is to be washed with 0.4 kg/s offresh water running countercurrent to the sandthrough two classifiers in series. Assume thatperfect mixing of the sand and water occurs ineach classifier and that the sand discharged fromeach classifier contains one part of water for everytwo of sand (by weight). If the washed sand is

dried in a kiln drier, what percent of salt will itretain?

0.49 0.43 0.29 0.25

70 Forty-five pounds per minute of water is heatedfrom 60 to 180 deg F in a 5/8 in., 16 BWG heatexchanger tube. If the steam condensing at 260deg F, on the outside of the tube gives an h of1000 Btu/hr-sq.ft.-degF, calculate the inside heattransfer coefficient [Btu/hr-cu.ft-degF].

2173.00 696.00 577.00 241.00

71 How many cu.ft. per minute of entering air isneeded to evaporate 10 lb of water per hour from arayon, if the air enters at 80 deg F and 25%humidity and leaves at 170 deg F and 55% relativehumidity. The operating pressure is 14.3 psia.

12.54 12.68 13.76 16.28


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72 Nicotine is to be extracted from water usingkerosene. If 100 lb of a 2% nicotine solution isextracted once with 200 lb of kerosene, whatpercent of the nicotine is extracted? {Equilibriumdata: Y[lb nicotene/lb kerosene] = 0.90X [lbnicotine/lb water]}

64.50 54.60 46.50 45.60

73 We must cool 2500 gpm of water from 120 to 80deg F. A cooling tower, at 70 deg F and 1 atm, is tobe designed to operate with entering air of 40%relative humidity. How many gpm of makeup water

must be supplied if windage loss is 95% of theamount lost by evaporation.

77.20 150.00 227.20 300.00

74 We wish to build an economical cold room 20 ftsquare and 10 ft high. The outside temperature is80 deg F and te room is to be maintained at 0 degF. The boss has suggested parallel wooden outerand inner walls separated by a 6-in air space.What will be the heat loss [Btu/hr] through eachwall?

3537.00 8457.00 11994.00 20451.00

75 A colloidal solution is to be concentrated from 15 to65% solids. The specific heat of the feed, enteringat 50 deg F is 0.93. The pressure of the saturatedsteam to the evaporator is 10 psia; the condenserpressure is 5-in. Hg abs. The steam chest has anoverall heat transfer coefficient of 200 Btu/hr-sq.ft.-

degF. Water must be evaporated at the rate of35,000 lb/hr. Neglecting boiling point elevation,what is the steam consumption [lb/hr]?

10500.00 35000.00 40130.00 45500.00

76 What is the settling time [sec] for galena particlesto settle under free settling conditions through 5 ftof water at 50 deg F. Galena is spherical in shape,with specific gravity and 0.01 inch in diameter.

38.10 18.30 13.80 5.00

77 A 10-ft diameter tank with a quick-opening value toa sump has a 10-ft depth of liquid. How long [t insec] does it take to drain the tank if the valve isassumed to be equivalent to a 4-in diameterorifice? The liquid density is 60 lb/cu.ft.

2951.00 1644.00 1163.00 19.40

78 What size sharp-edged orifice [inches] was in useif a flow of 120 gpm produced a 4-in Hg differential

in a 4-in Schedule 40 pipe. The fluid, measured at60 degF, had a viscosity of 1 cSt and a specificgravity of 1.

2.21 1.35 4.67 2.00

79 Seven hundred gallons per minute of water arebeing discharged by a centrifugal pump 5 ft abovethe pump inlet. The inlet pressure is 4-in Hg aboveatmospheric and the discharge pressure is 29 psia.If the pump has an 8-inch diameter inlet and a 4-inch diameter discharge, calculate the pumpefficiency.

63.00 84.00 95.00 100.00

80 Determine the net positive suction head availableto a centrifugal pump when the level of water is justat the suction point. The pumped fluid is water at140 deg F and it is pumped from an atmospheric

tank at 250 gpm. The tank suction point is 7 ftabove the pump. The piping is 5-in Schedule 40,10-ft long with two short radius 90 deg elbows.[Use density=61.38 lb/cuft, Pv=2.89 psi,viscosity=0.47 cP]

34.20 27.70 7.00 0.52

81 Water at 60 deg F flows through a 3-inch Schedule40 pipe. A pitot tube in the pipe shows a 3-inch Hgdifferential. If the pitot tube is located at the centerof the pipe, what is the mass flow rate of the water[lb/s]?

11.61 14.24 31.70 37.10


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82 The gas phase irreversible reaction A+B---->C iselementary. The entering flow rate of A is 10mol/min and is equal molar in A and B. Theentering concentration of A is 0.4 mol/L. WhatCSTR volume [L] is necessary to achieve 90%conversion?

113.00 227.00 851.00 900.00

83 The irreversible zero order gas phase dimerization2A ----->A2 is carried out in a packed bed reactorwith 5 kg of catalyst. The entering pressure is 10atm and the exit pressure is 1 atm. Pure A enters

at a flow rate of 10 mol/min. The reaction is zeroorder in A. What is the exit conversion?

0.15 0.50 0.75 1.00

84 The gas phase reaction 2A+B----->C is carried outin a PFR. The feed is equal molar in A and B andthe entering temperature is 500K and the enteringpressure is 16.4 atm. If the exit conversion isx,then the exit concentration of B is

[B]=0.4(1-x)/(1-0.5x)

[B]=0.4(1-x)/(1-1.5x) [B]=0.4(1-0.5x)/(1-x) [B]=0.2

85 Heat is generated in a 2.5 cm square copper rod atthe rate of 35.3e6 W/cu.m. The rod is exposed to aconvection environment at 20 deg C where theconvection heat transfer coefficient is 4 kW/sq.m.-degC. Determine the surface temperature [deg C]of the rod.

75.20 55.20 25.20 20.00

86 A 5cm diameter cylinder is maintained at a

constant temperature of 200 deg C and it is"completely enclosed" by a wind tunnel testchamber, walls of which are at 10 deg C. Air at350K is forced across the cylinder at a velocity of50 m/s (h=180 W/m-degC). If the surfaceemissivity of the cylinder is 0.7, determine the total(i.e., convective and radiative) heat transfer fromthe cylinder [W per meter length].

13.00 272.00 3478.00 3750.00

87 A building wall consists of a 6-in of concrete (kc=0.7 Btu/hr-ft-degF), 2 in of fiber insulating board,and 3/8 in of gypsum board (kg=0.03 Btu/hr-ft-degF). The inside and outside heat transfercoefficients are 2 and 7 Btu/hr-sqft-degF,respectively. The inside temperature is 72 degFand the outside temperature is 20 degF.

Determine the overall heat transfer coefficient forthis wall [Btu/hr-sqft-degF].

0.03 0.12 0.71 6.01

88 Current is passed through a cylindrical laboratoryheater, which has a 3 cm diameter, generatingheat at the rate of 20 MW/cu.m. The heater isexposed to a convection environment at 25 degCwhere the convection heat transfer coefficient is0.5 kW/sq.m.-degC. Determine its surfacetemperature [degC].

325.00 300.00 100.00 25.00

89 A straight rectangular fin has a length of 3.5 cm, athickness of 1.5 mm, and is made of a materialcharacterized by thermal conductivity of 255 W/m-degC. The fin is exposed to a convectionenvironment at 20 degC and h=1.5 kW/sq.m.-

degC. Determine the maximum possible heattransfer from this fin for the base temperature of150 degC.

1500 W 4392 W 13943 W 19343 W

90 A gaseous fuel is composed of 20% methane(CH4), 40% ethane (C2H6) and 40% propane(C3H8), where all percentages are by volume. Thevolumetric analysis of the dry products ofcombustion (ie. everything except the water) forthis fuel gives 10.6% carbon dioxide (CO2), 3%oxygen (O2), 1% carbon monoxide (CO) and85.4% nitrogen (N2). Determine the air fuel ratio ona mass basis for this reaction.

1.00 18.00 23.00 33.00


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91 Dodecane (C12H26) gas at 25 degC is burned in asteady flow combustion chamber with 20% excessair that enters at -23.15 degC. The products leavethe combustion chamber at 500K. Assumingsteady operating conditions and completecombustion, determine the required mass flow rateof the dodecane to supply heat at a rate of 1.5 kW[kg/s].

170.00 100.00 38.00 0.04

92 Two rooms A and B of identical volume areconnected by an open doorway. The thermostat in

the rooms are set so that Ta


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107 A furnace completely burns coal containing 70%C.Analysis of the flue gas shows 15% CO2, 4% O2,81% N2, and no CO. What is the % of the nethydrogen in the coal?

1.20 1.53 2.38 6.13

108 Which has the lowest water content? dew point at20degC

70% RH absolute humidity of0.05

60% saturation

109 A contract was made between a buyer and a papermanufacturer for paper containing 5% moisture atPhP450/tonne FOB on specifications that priceadjustment will be made if the quality is different.

How much should the buyer pay for 1 tonne ofpaper with 8% moisture content? Freight cost isPhP45/tonne.

PhP 405 PhP 424.26 PhP 434.16 PhP 450

110 One drier will dry a material from 45% moisture(wb) to 20% moisture (db). From here the materialenters another drier where the water content isfurther reduced to give a final product weighing1000 kg. If the total evporation from both driers is800 kg, the moisture of the final product is

0.01 0.02 0.03 0.05

111 An experimental oil is used to distill 6000 kg.hr ofAthabasta tar sand which analyzes 30% 'heavy oil','light oil', and non-volatile matter. If the distillatecontains 12 % heavy oil and this constitutes 25%recovery of the component, the weight in kg of the

distillate obtained is

2250.00 3750.00 4350.00 6000.00

112 Coal fired in a furnace has a heating value of13800 Btu/lb and contains 78.05%C and 1.2%S.The proximate analysis shows 4%M, 24%FC, 8%Aand the analysis of the refuse shows 8%VCM,25%FC and 32% ash. Calculate the % of C lost inthe refuse.

4.22 8.00 9.50 17.00

113 Ninety grams of ethane and 384 grams of oxygenare fed continuously to a laboratory furnace. Thetotal combustion products collected was 16.2gmole with no carbon dioxide. However, not all ofthe ethane was burned due to faulty combustion.The fraction of ethane that was burned is equal to

0.80 0.85 0.90 0.92

114 The furnace at the Bataan refinery is using a fuelgas which contains methane, ethane and 20%nitrogen. The orsat analysis of the combustionproducts showed 7.8% CO2, 7.4% O2, and 84.8%N2. The gas is burned with excess air. The %methane in the fuel gas is

63.25 57.24 51.20 22.76

115 Pyrite containing 78% FeS2 and 22% gangue isburned with excess air to produce a stack gas withthe following analysis: 7.29% SO2, 8.92%O2,82.44%N2 and 1.35%SO3. If the cinder was foundto have a partial analysis of 62.10% Fe2O3, the %of FeS2 lost in the pyrite is

3.52 6.53 7.86 23.10

116 The unit of k for a 1st order elementary reaction is 1/time conc/time 1/conc 1/conc-time

117 If the temperature of a chemical reaction is raisedby 10 degC, the rate of reaction is increased by afactor of

4.00 3.00 2.00 1.50

118 The E of a reaction may be lowered by increasingtemperature

decreasingtemperature

adding a catalyst removing theproducts of thereaction

119 The mechanism of a reaction can sometimes bededuced from

the activationenergy

the temperaturedependency of therate

the net equation the rate law.

120 The equilibrium constant in a reversible chemicalreaction at a given temperature

depends on theinitial conc of thereactants

depends on the concof one of the productsat equilibrium

does not depend on theinitial concentrations

is not a characteristicof the reaction

121 If the volume of a reaction vessel is suddenlyreduced to one half its original volume the rate will

2.00 4.00 8.00 16.00


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increase by a factor of

122 The rate of reaction is not influenced by conc of thereactants

molecularity of thereaction

nature of reactants temperature

123 The net rate of reaction of an intermediate is 0.00 2.00 > 0 B+C is second order, whichof the following plots will give a straight line?

Ca^2 vs time 1/Ca vs time lof Ca vs time Ca vs time

126 For the reaction A+B ---> 2C, when Ca is doubledthe rate doubles, when Cb is doubled the rateincreases fourfold. The rate law is

-ra = k Ca^2 Cb^4 -ra = k Ca Cb^2 -ra = k Ca -ra = k Cb^2

127 It states that the rate of a chemical reaction isproportional to the activity of the reactants.

Le Chatelier'sprinciple

Hess' Law Law of Mass Action Second Law ofThermo

128 The half life of a material undergoing second orderdecay is

proportional to thesquare of the initialconc

independent of initialconc

proportional to initialconc

inversely proportionato initial conc

129 A fluid flows through 2 CSTR in series. Eachreactor has a capacity of 400,000 L and the fluidenters at 100 L per hr. The fluid undergoes a firstorder decay with a half life of 24 hours. Find theconversion of the fluid.

66.80 74.70 85.30 99.10

130 A first order reaction has a specific rate constant of

3e-3 per sec. The half life is

0.0021 s 100 s 231 s 768 s

131 A certain reaction is 1st order in A. In 30 min, theconcentration of A decreases from 0.55 to 0.15mol/L. The time it will take for A to decrease from0.35 to 0.15 mol/L is

45.1 min 19.6 min 19.1 min 10.4 min

132 A gas decomposes at 900 degC according to 2A--->2R+S with a rate constant of 1000 cc/gmol-susing pure A. The time it will take to react 80% of Ain a batch reactor at 900 degC and 1 atm in min is

3.83 7.43 8.33 9.33

133 Calculate the length of a chlorinating pipe line withdiameter of 0.6 m required to kill 95% of thebacteria in waste water flowing at 0.05 cu.m/s. Testshows that 95.33% kill is obtained in 5 minuteswhen treated with 5 mg/L of chlorine. Chlorine

disinfection kinetics is given by the equation: dC/dt= k Ct^1.5 where C = number of bacteria.Assume that the same concentration of chlorine isused in actual treatment operation.

25.36 m 32.5 m 52.63 m 56.23 m

134 The set of data given below is for the parallelreaction: a---k1-->2R, a---k2-->S. At t=0, Ca=15moles/cuft, Cr = 1 mole/cuft, Cs=1 mole/cuft; At t=1hr, Cro = 9 moles/cuft, Cs = 3 moles/cuft. Thevalue of K2 per hour is

0.17 0.18 0.34 0.62

135 A batch reaction 2D+E----->F has a conversionfactor expressed by the equation r =0.24 t^0.5where r = conversion factor based on the reactantE; t = time in hours which ranges from 0.5 to 16hours per batch depending upon the processvariables. The average molecular weight of thefeed is 60 and a density of 1.4 g/cc. The feedconsists of 2 kgmole of D and 1 kgmole of E. Thecharging, cleaning and discharging time per batchis 2.5 hrs and the volume of the reactor is twice thevolume of the feed. Assume 300 days per year and12 hours operation/day. The volume of the reactorin liters is

257.00 275.00 300.00 527.00


11/19


136 A container holds 100 gal of salt solutioncontaining 50 lb of dissolved salt. The bottom ofthe container is covered with a layer of rock salt.The bottom of the container is covered with a layerof rock salt whose surface is practically constant.The salt dissolved into the solution according to r =k(C-3) where C is the concentration of the brineexpressed in lb/gal. If the water in the tank werefresh, the rate of solution would be 1.0 lb/min.Fresh water enters at 3 gpm and brine overflows atthe same rate. Assume constant volume at anybrine concentration, the concentration of brine incontainer after 1 hour in lb/gal of salt is

0.73 0.43 0.33 0.24

137 An aqueous solution of ethyl acetate is to besaponified with NaOH. The initial concentration ofthe ethyl acetate is 5 g/L and that of the causticsoda is 0.10M. Values of the second order rateconstant in L/gmole-min are k = 23.5 at 0 degC; k= 92.4 at 20 degC. The reaction is essentiallyirreversible. The time required to saponify 95% ofthe water at 40 deg C is

10.30 11.40 12.70 20.70

138 At 500K the rate of bimolecular reaction is 10 timesthe rate at 400K. Find E in cal, the activationenergy for this reaction from Arrhenius Law.

8150.00 9150.00 9550.00 10150.00

139 The reaction A+2B--->R is 1st order with respect to

each reactant. If equimolar amounts of A and B areintroduced into a constant-volume reactor and(1/m) th of A remains after t1, how much willremain after t2=2t1?

Cao/2m Cao/(2m-1) Cao/(1-2m) Cao/2

140 When the 1st order homogeneous reaction (gas-phase) A--->2.5R is carried out in an isothermalbatch reactor at 2 atm with 20% inerts present, thevolume increases by 60% in 20 min. When thereaction is carried out in a constant volume reactor,the time required for the pressure to reach 8 atm ifthe initial pressure is 5 atm, 2 atm of which consistof inerts in min is

43.10 41.30 37.10 31.80

141 When the ID of the pipe through which a fluid flowsis doubled, the pressure loss due to friction per unit

length of pipe and for the same volumetric flow rateis changed by approximately a factor of

1/8 1/16 1/32 1/64

142 When two centrifugal pumps are connected inseries, the discharge changes by a factor of

1/2 1.00 2.00 4.00

143 When two reciprocating pumps are connected inparallel, the volumetric capacity of the systemchanges by a factor of

1/2 1.00 2.00 4.00

144 The pressure drop in a pipeline changes by afactor of _____ when the velocity of the flowingfluid is doubled.

1/2 1.00 2.00 4.00

145 Cavitation occurs in a centrifugal pump when the dischargepressure becomestoo high

the discharge valve isclosed

the suction pressure istoo high

suction is lost

146 Oil with a viscosity of 30 cP and a density of 60lb/cu.ft. flows through a 1/2-inch inside diameterpipe. Determine the velocity in fps below whichflow will be laminar.

0.63 13.10 16.90 87.20

147 Water at 60 deg F flows through a 3-inch insidediameter smooth horizontal pipe. If the Reynold'snumber is 353000, calculate the ratio of maximumvelocity to average velocity.

1.05 1.22 1.72 1.89

148 The pressure after the pump in a 6-inch insidediameter smooth pipe conducting water is 20 psia.The water is discharged at an open tank 100 ftfrom the pump. Calculate the rate of discharge ofwater in cu.ft/s.

0.60 3.58 21.00 58.30


12/19


149 A water storage tank assumes the supply of waterinto a factory. Water is supplied to the tank througha booster pump installed in the water line. Thetheoretical pump horsepower required is 3.25 hp.What is the monthly operating cost of the pump ifelectric power cost on the average is PhP3.73/kWh. The pump is 65% efficient and operatesfor 12 hr a day.

PhP 3300 PhP 5000 PhP 7000 PhP 12000

150 When the impeller speed of an ideal centrifugalpump is doubled, the vol. flow rate of discharge is

increased by a factor of

1/2 1.00 2.00 2exp2

151 The differential height between two points which afluid has to be transferred is the

potential head pressure head velocity head dynamic head

152 The resistance of a layer of fluid to flow over thenext layer is measured by

viscosity friction factor surface tension drag coefficient

153 An axial flow pump operating at a speed of 880rpm can supply water at a rate of 3000 gpm. Themaximum head that this pump can deliver in ft. ofwater is

20.00 36.00 63.00 85.00

154 Specify the type of open impeller pump to use ifthe capacity is 400 gpm at a head of 200 ft ofwater.

3x2x8.5E 4x3x8.5E 4x3x6 3x2x13

155 What will be the rated capacity [gpm] of a 4-1/2inch impeller centrifugal pump operating at a speed

of 3450 rpm capable of generating a head of 40 ftof water.

95.00 134.00 248.00 320.00

156 If the speed of a centrifugal pump is doubled, theenergy requirement becomes approximately ___times the original energy requirement.

2.00 4.00 8.00 10.00

157 A cylindrical tank 1 ft in diameter dischargesthrough a nozzle connected to the base. Find thetime needed for the water level in the tank to dropfrom 4 ft to 2 ft above the nozzle. The diameter ofthe nozzle is 1 inch and its discharge coefficientmaybe taken as unity.

32.00 55.00 77.00 94.00

158 The NPSH of a single suction centrifugal hot waterpump at a speed of 3550 rpm operating at apressure of 600 psi and a capacity of 450 gpm is

___ ft.

15.00 20.00 25.00 30.00

159 The rate of evaporation at a given operatingtemperature in a n evaporator is more when

when the operatingpressure is high

the operating pressureis low

there is a vacuum when the liquid levelis high

160 An optimim number of the effects for a givenapplication is a function of the

capacity economy efficiency none of the givenchoices

161 A popular type of heat exchanger for cooling largequantities of fluid is the

double-pipe plate shell and tube extended surfaces

162 An evaporator is used to concentrate 10,000 lb/hrof a 20% solution of NaOH in water at 140 oF usingsaturated steam at 25 psia at a rate of 7,000 lb/hr.The OHTC is 275 BTU/hr-ft2-oF when the pressurein the vapor is 1.7 psia. The steam economy, SE,is

0.82 0.86 0.89 0.92

163 A cross flow heat exchanger uses mixed air at 4kg/s that enters at 15oC and leaves at 45oC. Theair cools unmixed water, which enters at 95oC and0.70 kg/s. The OHTC equals 150 W/m2-oC. Afterseveral months of operation, a scale resistance of0.002 m2-oC/W developed. 16. The heat transferarea required to accomplish the change is

22.2 m2 25 m2 17 m2 20 m2


13/19


164 As solution of 28% wt Na2SO4 is to be crystallizedto yield Glauber salt in a four section (one sectionis 10 ft in length) Swenson Walker Crystallizer. It isfed to the unit at 120oF and cooled to 60oF usingcooling water which enters at 50oF and leaves at70oF. The crystallizer has a cooling surface of 3 ft2per foot of length. The feed rate is 500 lb/hr andthe crystallizer is seeded with 50 lb/hr of 65 meshcrystals. 19. The amount of the crystalline crop (C)produced in lb per hour is

285.30 249.30 255.65 214.65

165 An insulator should have low thermalconductivity high thermalconductivity less resistance to heatflow a porous structure

166 Fouling factor is a dimensionlessquantity

does not provide asafety factor for design

accounts for additionalresistance to heat flow

none of these

167 Natural convection is characterized by Reynolds number Grashhoff number Peclet number Prandlt number

168 The Graetz number is concerned with mass transferbetween a gas anda liquid

absorption withchemical reaction

heat transfer inturbulent flow

heat transfer inlaminar flow

169 Dropwise condensation occurs on clean and dirt freesurfaces

smooth clean surfaces contaminated coolingsurfaces

polished surfaces

170 Dietus-Boelter equation for determination of heattransfer co-efficient is valid

for liquid metals for fluid in laminar flow for fluids in turbulentflow

when Grashhoffnumber is very

important

171 A type of pneumatic conveyor systemcharacterized by a material moving in an air streamor pressure less than ambient.

fluidiz ing pressure pressure-vacuum vacuum

172 If the total percentage of particles larger than thescreen opening in the feed, oversize, undersize are36%, 89% and 3%, respectively, the effectivenessof the screen if the undersize is the product is

0.98 0.89 0.76 0.65

173 The estimated width of an apron conveyor having acapacity of 75 tons/hr at a speed of 50 ft/min is

305 mm 610 mm 1220 mm 2400 mm

174 It is defined as the ratio of the average diameter ofthe feed to the average diameter of the product.

settling ratio screen-mesh no reduction ratio average particlediameter

175 The sphericity of cubical particles is 1.00 0.87 0.70 0.60

176 The separation of a dilute slurry or suspension bygravity settling into a clear fluid and a slurry orsuspension by gravity settling into a clear fluid anda slurry of higher solids content is called

thickening classification sorting centrifugation

177 An ultracentrifuge is used to separate high-molecular weight fractions in polymeric orbiological systems. What is the gradient for masstransfer in the separation using this mass transferdevice?

temperature pressure concentration electric field

178 Ordinary diffusion takes place because of ___driving force.

temperature pressure concentration electric field

179 What are the two limiting cases of steady-statediffusion?

UMD and EMD ordinary and Knudsen thermal and ordinary thermal and Knudsen

180 Which of the following is not true in (binary)

equimolar counter-diffusion?

DAB = DBA c = cA + cB JA = JB NA = -cDAB dxA/dz

181 A fluid is flowing on a surface, which contains acomponent that leaches out to the fluid. Assumingthat all the 3 regions of mass transfer are present,in which of these regions is diffusion controlling?

Knudsen region turbulent region buffer region viscous sub-layer

182 In unsteady-state mass transfer, the quantity(DABt/rm^2) is referred to as

unaccomplishedchange

relative resistance relative time relative position

183 What is the equivalent of Prandtl number inconvective mass transfer?

Sc Sh Bi Pe

184 If kx > ky, then the controlling phase is the liquid phase the gas phase the interface either of the bulkphases

185 In two-phase mass transfer, equilibrium may exist at the interface in the gas phase in the liquid phase in either film


14/19


186 Which of the following processes may always beregarded as a constant- humidity process?

cooling of air air conditioning water-cooling in acooling tower

heating of air

187 Air conditioning in tropical countries involves humidification by aprocess similar tothat in a coolingtower

humidification by aprocess similar to air-water vapor saturator

dehumidification andremoval of sensibleheat

dehumidification bycondensing watervapor in arefrigerator

188 What do you call the steady-state non-equilibriumtemperature reached when a small amount ofwater is contacted under adiabatic conditions by acontinuous stream of gas?

dry-bulbtemperature

wet-bulb temperature adiabatic saturationtemperature

dew pointtemperature

189 The moisture content of a solid is given as 50%wet basis. What is the moisture content, drybasis?

0.50 1.00 2.00 50.00

190 The moisture that can be removed by drying iscalled

equilibriummoisture

bound moisture free moisture unbound moisture

191 Falling-period in drying terminates at the end of constant-rateperiod

origin of R vs X plot critical free moisturecontent

equilibrium moisturecontent

192 Which is not true at the interphase of a gasscrubbing operation?

the soluteconcentration of thegas is less than thatof the bulk

the soluteconcentration of theliquid is less than thatof the bulk

the solute concentrationof the liquid and gasphase are equal

the soluteconcentration of thegas is greater thanthe liquid

193 He and N2 gas are contained in a conduit 5 mm in

diameter and a 0.1 m long at 298 K and a uniformpressure of He at one end of the tube is 0.6 atmand 0.02 atm at the other end. Assumingequimolar countercurrent diffusion, the flux inkmol/s-m2 is

2.35 exp -5 2.44exp -5 1.77exp -6 1.22 exp -6

194 100 m3/hr of air at 60C and 20% RH is needed fora chemical reactor. This will be obtained fromprocess air at 60C and 10% RH by humidifyingadiabatically the process air followed by heating toits original temperature. The wattage of the heaterat 80% efficiency is

5280.00 8490.00 10050.00 11570.00

195 Wet solid is to be dried from 36% to 8% moisture in5 hr under constant drying condition. Critical andequilibrium moisture contents are 14 and 4%respectively. Calculate how much longer will it taketo dry the same material from 8% to 5.5% moistureunder constant drying condition. All moisturecontents are on a dry basis.

1 hr 1.6 hr 2.3 hr 2.9 hr

196 The unit of volumetric diffusivity is cm^2/sec cm/sec cm^3/sec cm^2/sec^2

197 If reflux to a distillation column is 100 moles/hr,when the overhead product rate is 50 moles/hr. thereflux ratio is

0.50 2.00 50.00 150.00

198 Which of the following provides maximum contactsurface for a liquid-vapour system?

packed lower bubble-cup platecolumn

sieve-plate column wetted wall column

199 In extraction, as the temperature increases, thearea of heterogeneity (area covered by bimodalcurve)

decreases increases remains unchanged

200 The suitable evaporator for concentration of

foaming liquids is

long tube

evaporator

short tube evaporator vacuum evaporator falling film evaporato

201 Macroscopic transfer of mass between movingfluid and surface which is of different concentrationis called

molecular diffusion unsteady-statediffusion

convective masstransfer

all of these

202 For a packed column the main purpose of packingis to

strengthen thecolumn

increase the surfacearea

increase the pressuredrop in the tower

reduce the flow rateacross the column

203 In a gas absorption operation, when the operatingline crosses the equilibrium curve

the NTU is zero the liquid flow rate ismaximum

the gas flow rate ismaximum

the number of stagesis infinite


15/19


204 Methanol diffuses in 0.15 cm stagnant film of 1:1mole mixture of hydrogen and CO2 at 100oC and 2atm. The partial pressures of methanol on bothsides are 0.6 and 0.2 atm. The average diffusivityof methanol in the hydrogen and CO2 at 0 oC and 1atm in cm2/s is

0.15 0.31 0.51 0.68

205 Gaseous reactant A decomposes according to thereaction A --> 3R (-rA = 0.5 CA mole/L-min). Thefeed, which consists of 70% A and 30% inert,enters a 1.5-m3 CSTR at a flow rate of 150 L/min.

4. If CA0 = 0.30 mole/L, what is the conversion,XA?

0.92 0.86 0.71 0.65

206 Between 0 degC and 50 degC, the averageactivation energy of a certain reaction is 80 kJ/mol.How many times faster will the reaction occur at300 K than at 275 K?

14.70 18.50 20.90 22.40

207 Consider a gas-phase reaction 2A ---> R + 2S withunknown kinetics. A space velocity of 0.8/min isneeded for 95% conversion of A in a PFR. Find themean residence time or holding time of the fluid inthe PFR.

0.54 min 0.85 min 0.87 min 1.18 min

208 For Newtonian fluids, the shear stress is constant. inversely proportionalto rate of deformation.

equal to shear rate ofdeformation.

a linear function ofthe shear rate ofdeformation.

209 An ideal fluid is one that is compressible incompressible &viscous

incompressible incompressible &inviscid

210 Water flows through an 8-in (ID=7.981 in) steelpipe at an average velocity of 6 ft/s. Downstreamthe pipe splits into an 8-in main and a 2 in(ID=2.067 in) bypass pipes. If the velocity in thebypass is twice the velocity of the main pipe, thevolumetric flow rate [ft3/s] in the main pipe is

10.58 5.29 1.84 0.25

211 An imaginary line within a fluid flow such that atangent at any point indicates the direction of flowat that point.

stream tube velocity profile streamline none of these

212 Air at 250C [viscosity=0.018 cP] enters a section of2-in schedule 40 commercial steel pipe at a gaugepressure of 310 kPa and a flow rate of 1200 kg/h.

Assuming isothermal flow, what is the pressuredrop [kPa] in 60 m of pipe?

350.00 155.00 101.30 61.00

213 A simple pitot tube measures acoustical velocity superficial velocity mean linear velocity local velocity

214 Which of the following meters will have the highestpermanent pressure loss?

pitot tube orifice venturi rotameter

215 In the flow meter equation, Y, indicates the mass flow rate compressibility factor coefficient of discharge cross-sectional area

216 The loss due to sudden contraction is proportionalto

velocity turbulence velocity head static head

217 Stokes law is valid when the particle Reynoldsnumber is

< 1 > 1 < 5 0.00

218 Priming needed in a Reciprocating pump Gear pump Centrifugal pump Diaphragm pump

219 Maximum theoretical suction lift for water at 60Fby a centrifugal pump is 34 ft. The same for waterat 200F will be

40 ft 37 ft 34 ft 8 ft

220 The most economical valve for use with largediameter pipes.

butterfly globe needle gate

221 Multistage compressors are used in industrybecause, they

reduce the cost ofcompressor

reduce the sizerequirement

resemble closely toisothermal compression

are easy to control

222 For ideally incompressible fluid, the mach numberwill be

0.00 1.00 1.50 5.00

223 of the following produces maximum pressuredifference for transportation of gases?

vacuum pumps blowers fans compressors


16/19


224 The fluid property which matters for falling raindrops to acquire spherical shape is its

pressure height of descend viscosity surface tension

225 A wastewater solution having a volume of 1000 Lcontains 0.21 kg phenol/m3 of solution. A total of1.40 kg fresh granular activated carbon is added tothe solution, which is then mixed thoroughly toreach equilibrium. What is the amount of phenolabsorbed per kg carbon at equilibrium?

0.007 kg 0.106 kg 0.189 kg 0.198 kg

226 The overhead product composition decreases withtime in

batch distillationwith reflux

continuous distillationwith reflux

continuous distillationwithout reflux

distillation operatingat total reflux

227 For a binary mixture with low relativity, continuousrectification to get pure products will require

low reflux ratio small cross-section less number of trays high reflux ratio

228 Chemisorption is the same as vander Waals

characterized byadsorption of heat

an irreversiblephenomenon

always in equilibrium

229 The stage efficiency in leaching depends on the time of contactbetween the solidand the solution

rate of diffusion of thesolute through thesolid and into theliquid

both A and B either A or Bbecause these twomean the same thing

230 Weeping in distillation or absorption column increases trayefficiency

provides largersurface for masstransfer

results due to low gasvelocity

is due to bubble cups

231 What are the two contacting phase in leaching? extract phase and

raffinate phase

solvent phase and

solute phase

feed phase and solvent

phase

overflow and

underflow

232 Hydrogen sulfide is removed from water bycontacting the solution with warm air. Theoperation is

Distillation Leaching Absorption Stripping

233 Disregarding the cost, which is the best solvent forthe extraction of acetic acid from an aqueoussolution at 25deg C?

caproic acid chloroform 3-heptanol toluene

234 Professional Regulations Commission was createdunder

P.D. No. 223 P.D. No. 233 P.D. No. 232 P.D. No. 826

235 A chemical engineer who designed and built a newtype pf reactor and for three years, sold many unitsto the public can still patent his reactor.

TRUE FALSE it depends not governed by law

236 A person who has passed the Chemical Licensure

Examination can take his/her oath as a chemicalengineer if his/her age is not less than _______years.

18.00 19.00 21.00 23.00

237 Which of the following is not a requirement forutility model registration?

inventive step novelty industrial applicability a technical solutionto problem

238 A section of the patent application containingdetailed descriptions of the benefits obtained fromusing the invention is called the

disclosure abstract request claims

239 A document issued by the DENR secretaryindicating that the proposed project will causesignificant negative environmental impact.

EnvironmentalImpact Statement

EnvironmentalCompliance Certificate

Environmental ImpactAssessment

EnvironmentalCritical Project

240 In the Philippines, sulfur for sulfuric acidmanufacturing is sourced from _______ industry.

paper cement petroleum detergents

241 Sulfur is undesirable in petroleum because it causes engineknocking

it increases the boilingpt of fuel

it poisons the catalyst inthe refining process

all that arementioned

242 Materials added to detergent formulation toenhance cleaning performance by exhibitingsynergistic cleaning effect with surfactant.

fillers brighteners builders perfume

243 Polyethylene is an example of _____________polymerization

condensation addition copolymerization natural

244 Principal chemical conversion in the production ofresin from monomer.

condensation hydration polymerization alkylation

245 Carbon black is added to rubber compounding as activator curing agent retarders fillers

246 The binder for all the powder materials of paint pigment vehicle opacifier filler


17/19


247 A fibrous material left after cane sugar has beenmilled is commonly called as

bagasse pulp cellulose waste

248 Molasses is a by product of raw sugar from the______ process

milling extraction evaporation crystallization

249 Kraft process is a common name for sulfate pulping sulfite pulping bleaching calendering

250 Water insoluble cell binders of wood pulp cellulose xylem lignin

251 DDT means Diphenyldichlorotriphenylethane

dichlorodiphenyldichloroethane

Dichlorodiphenyldichlorobutane

diphenyldichlorotriphenylbutane

252 Rancidity of oil can be reduced by decoloration hydrogenation oxidation purification

253 Varnish does not contain pigment dryer thinner anti-skinning agent

254 Plasticizers are added to paints to make it corrosionresistant

make glossy surface increase atmosphericoxidation

give elasticity andprevent cracking ofthe film

255 Silicone is thermoplastic a monomer an inorganic polymer thermosetting plastic

256 The process involved in converting rubber into athin sheet or coating it on fabric is called

extrusion mastication vulcanization calendering

257 Alkyl benzene sulfonate (ABS) is a detergent rubber pesticide polyester

258 Neoprene is a monomer synthetic rubber polyester pigment

259 Steam enters an adiabatic turbine at 10 MPa and

500deg

C at a rate of 3 kg/s and leaves at 0.1 MPa.If the power output of the turbine is 2 MW,determine the turbine efficiency.

0.23 0.32 0.68 0.77

260 Work is a property of thesystem

path function state function state description of asystem

261 Throttling process is a reversible andisothermal process

an irreversible andconstant entropy

a reversible andconstant entropyprocess

constant enthalpyprocess

262 A sample consisting of 1.00 mole of Argon gas isexpanded isothermally and reversibly at 0C from22.4L to 44.8L. The heat absorbed by the systemis

0.00 +1.13 kJ +1.57 kJ +2.27 kJ

263 Maximum work can be obtained from a systemwhen the change taking place in it is

isothermal adiabatic reversible irreversible

264 The ratio of work performed by a system and theheat it absorbed from a reservoir is referred to

Entropy Gibbs free energy carnot efficiency Helmholtz freeenergy

265 According to the first law of thermodynamics Energy is neitherlost nor gained inany energytransformation.

Perpetual motion ispossible.

Energy is conserved inquality but not inquantity.

Energy is beingcreated as timepasses. We havemore energy in theuniverse now thanwhen time began.

266 In a 3-stage compressor system whose isentropicefficiencies are reported to be 0.75, 0.85 and 0.84,respectively, steam initially at 10 kPa iscompressed to a final pressure of 500 kPa. Theoverall efficiency of the system is

greater than 0.85 in between 0.75 and0.85

less than 0.75 in between 0.84 and0.90

267 In choosing the refrigerant, the fluid must have the

following characteristics, except

environmentally

benign

has a vapor pressure

less than atmospheric

must be economically

viable

exist at a high

pressure at thecondensationtemperature

268 Coolers and boilers are ordinarily operated at________ condition.

isobaric isenthalpic isothermal isentropic

269 For an isolated system, maximum entropy willoccur at

half-life critical condition equilibrium start of the process

270 A carnot cycle consists of two isothermal andtwo adiabaticprocess

two isochoric and twoadiabatic process

one isochoric, oneisobaric, and twoadiabatic process

one isothermal, oneisochoric and twoadiabatic process

271 This is also known as the volume fraction of thevoids in packed beds.

sphericity porosity superficial velocity specific volume


18/19


272 A measure of the ratio of the drag force acting on aunit area of the impeller & the inertial stress.

Froude number Reynolds number Mach number Power number

273 Sulfuric acid is pumped at 3 kg/s through a 60-mlength of smooth 25 mm pipe. If the pressure dropfalls by one-half, what will be the new flow rate[kg/s]? Assume the following properties of sulfuricacid: SG = 1.84, viscosity = 25 cP.

3.00 2.00 0.20 0.12

274 The equation del(P) = -(rho)(g) del(z) is known asthe hydrostatic vertical law for which all thefollowing assumptions are applied, except

shear forces are notinvolved

fluid is incompressible z axis is defined vertical& downward in direction

normal surfaceforces & gravity arethe only forces

involved275 Which of the following can be adjusted by human

operator in a closed feedback control loop?set point controller output process variable load variable

276 The thermocouple is based on the Seebeck effectwhich states that a/an _____ is generated whenopposite junction of certain dissimilar pairs of wiresare exposed to different temperatures.

current temperature emf resistance

277 Dead time is a function of distance and momentum acceleration time velocity

278 A pneumatic controller is used to controltemperature within the range 280K to 310K. Thecontroller is adjusted so that the output pressuregoes from 20kPa (valve fully open) to 105 Kpa(valve fully closed) as the measured temperaturegoes from 295K to 300K with the sent point held

constant. What is the proportional gain?

2.83kPa/K 0.35kPa/K 17kPa/K 0.06kPa/K

279 The parameter which completely describes thebehavior of the response to a disturbance of asecond order system is the

Time constant damping coefficient Rise time overshoot

280 Water is flowing through a 3-inch schedule 40 pipeat 60 deg F. A pitot tube is inserted at thecenterline of the pipe and registers a 3-inch Hgdifferential. What is the mass flow rate of thewater?

11.61 ft/s 37.1 kg/s 37.1 lb/s 317 lb/s

281 An oil well is 1200 ft below ground level. Oil at 500psig at the bottom flows to ground level through a12-inch schedule 80 commercial steel pipe. The oilhas a SG of 0.86 and viscosity of 8 cP. The volflow rate of oil in barrels per hour is

9365.00 9461.00 52581.00 393308.00

282 The equivalent diameter of a concentric annularspace where 1-inch OD pipe is located inside a 2-inch ID pipe is

pi/4 inch 1 inch 1.5 inch 2 inches

283 Based on Bond's crushing law, the power requiredto crush a certain material will change by _____%if the diameter of the product is made smaller by50%.

20.20 41.40 50.50 58.60

284 The BPR of a 50% NaOH solution at an evaporatorpressure of 4.7 psia is

73 degF 173 degF 233 degF 297 degF


19/19

ANSWERS

1 A 51 C 101 A 151 A 201 C 251 C

2 C 52 A 102 B 152 A 202 B 252 B

3 D 53 B 103 A 153 B 203 D 253 A

4 D 54 B 104 B 154 A 204 C 254 D

5 B 55 A 105 C 155 C 205 C 255 C

6 C 56 C 106 a 156 C 206 B 256 D

7 C 57 C 107 C 157 C 207 B 257 A

8 C 58 B 108 A 158 B 208 D 258 B

9 D 59 C 109 C 159 B 209 D 259 C10 C 60 D 110 A 160 B 210 C 260 B

11 D 61 C 111 B 161 C 211 C 261 D

12 C 62 D 112 C 162 B 212 D 262 C

13 C 63 B 113 A 163 D 213 D 263 C

14 C 64 A 114 B 164 B 214 B 264 C

15 C 65 A 115 B 165 A 215 B 265 A

16 A 66 C 116 A 166 C 216 C 266 B

17 B 67 A 117 C 167 B 217 A 267 D

18 B 68 C 118 C 168 D 218 C 268 A

19 D 69 D 119 D 169 C 219 B 269 C

20 B 70 A 120 C 170 C 220 A 270 A

21 C 71 B 121 D 171 D 221 C 271 B

22 D 72 A 122 C 172 B 222 B 272 D

23 B 73 B 123 A 173 C 223 D 273 B

24 D 74 D 124 A 174 C 224 D 274 C25 D 75 C 125 B 175 A 225 B 275 A

26 C 76 B 126 B 176 A 226 A 276 C

27 B 77 C 127 C 177 B 227 D 277 D

28 B 78 A 128 D 178 B 228 C 278 C

29 B 79 B 129 D 179 A 229 C 279 B

30 C 80 A 130 C 180 C 230 C 280 C

31 C 81 D 131 B 181 D 231 D 281 A

32 B 82 C 132 C 182 C 232 D 282 B

33 B 83 C 133 C 183 A 233 C 283 B

34 A 84 D 134 A 184 B 234 A 284 A

35 C 85 A 135 A 185 A 235 A

36 B 86 D 136 C 186 D 236 C

37 B 87 B 137 A 187 C 237 A

38 C 88 A 138 B 188 B 238 D

39 B 89 C 139 B 189 B 239 B

40 A 90 B 140 D 190 C 240 A

41 A 91 D 141 C 191 D 241 A

42 A 92 A 142 C 192 A 242 C

43 B 93 C 143 B 193 A 243 B

44 B 94 C 144 D 194 D 244 D

45 C 95 A 145 C 195 B 245 A

46 C 96 D 146 C 196 C 246 A

47 A 97 D 147 B 197 B 247 C

48 D 98 B 148 B 198 A 248 C

49 B 99 B 149 B 199 A 249 B

50 C 100 B 150 C 200 A 250 D

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Chemical Engineering Review Questions[1]