111-118 Flashcards
(135 cards)
1
Q
1000 cfm of air AT 95°F dry bulb, 74°F is mixed with 2000 cfm of air at 65°F dry bulb, 54°F wet bulb. Determine the dry bulb temperature of the mixed stream.
A. 74.7°F
B. 85.7°F
C. 98.4°F
D. 107.5°F
A
A. 74.7°F
2
Q
From the data in problem #1, determine the wet bulb temperature of the mixed stream
A. 61°F
B. 74.7°F
C. 85.7°F
D. 98.4°F
A
A. 61°F
3
Q
From the data in problem #1, determine the volumetric flow rate of the mixed stream
A. 1845 cfm
B. 2445 cfm
C. 2745 cfm
D. 3014 cfm
A
D. 3014 cfm
4
Q
A slab of paper pulp, 4 ft by 4 ft by ¼ in is to be dried under constant drying conditions from 66.7% water to 35% water wet basis. It is to be dried under such conditions that the drying rate at the critical point will be 0.307 lb/hr-ft^2. The dry material in one slab weighs 5 lb. how long will the drying process take? Data: equilibrium moisture content=0.5% wet basis, critical moisture content=1.675 lb H2O/lb dry stock
A. 0.09 hrs
B. 1.13 hrs
C. 2.45 hrs
D. 3.98 hrs
A
B. 1.13 hrs
4
Q
Air at 100 kPa pressure and a dry-bulb temperature of 93°C and wet-bulb temperature of 35°C is fed to a dryer. In the dryer 0.03 kmol of water evaporates per kmol of air fed to the dryer. If the vaporization of water in the dryer is adiabatic, calculate the dry-bulb temperature of the air leaving the dryer.
A. 32.1°C
B. 40.8°C
C. 47.5°C
D. 55.8°C
A
C. 47.5°C
5
Q
From the data in problem #5, calculate the wet-bulb temperature of the air leaving the dryer.
A. 27°C
B. 35°C
C. 42°C
D. 48°C
A
B. 35°C
6
Q
From the data in problem #5, the percentage saturation of the air leaving the dryer
A. 30.1%
B. 41.7%
C. 54.3%
D. 65.1%
A
B. 41.7%
7
Q
A gasoline tank consists of horizontal cylinder 30 cm in diameter and 1.5 m long. Determine the number of liters in tank hen the gauge rod in the plane of vertical diameter shows a depth of 10 cm in the tank (1m3
= 1000L)
A. 31.5
B. 48.2
C. 63.4
D. 85.7
A
A. 31.5
8
Q
Ethyl benzene decomposes according to the reaction C6H5C2H5 → C6H5C2H3 + H2. The reaction rate constants at two temperatures are as follows:
Temp, °C 540 550
K x 10^4 1.6 2.8
Calculate the activation energy of the reaction in kJ/kmol.
A. 311308
B. 245200
C. 2104451
D. 278500
A
A. 311308
9
Q
You just deposited $1,500 into a savings account that pays 9% interest, compounded annually. If you intend to take out $200 at the end of the first quarter, $400 at the end of the second quarter, and $800at the end of the third quarter, what is the maximum amount that you can withdraw at the end of the 4th quarter?
A. $176
B. $184
C. $191
D. $200
A
C. $191
10
Q
What is the bubble point temperature of a ternary liquid mixture consisting of 50 mol% benzene, 30 mol% toluene and 20 mol% ethyl benzene is the system is 760 mmHg?
A. 94.3°C
B. 82.7°C
C. 72.4°C
D. 64.2°C
A
A. 94.3°C
11
Q
A motor is used to stir a 5 kg water at 0.4 Hp. Assuming that there was no loses and all the work went into heating, how long will it take to increase the temperature of water by 6°C?
A. 7 min
B. 5 min
C. 10 min
D. 12 min
A
A. 7 min
12
Q
A vessel contains a liquid mixture of 50% benzene and 50% toluene by weight at 100°C.the average molecular weight of the vapor in contact with the solution is very nearly
A. 82
B. 88
C. 78
D. 92
A
A. 82
13
Q
What is the molar specific volume of a gas in m^3
/kmol at 1.722 MPa and 99°C if the compressibility of the gas at these conditions is 0.87?
A. 5.1
B. 2.1
C. 1.6
D. 3.5
A
C. 1.6
14
Q
Calculate the heat of vaporization of HFC-134 at 40°C in kJ/kg.
A. 85
B. 110
C. 171
D. 152
A
C. 171
15
Q
In the Lineweaver-Burk double reciprocal plot the slope is equal to
A. 1/[S]
B. 1/V
C. Km/Vmax
D. 1/Vmax
A
C. Km/Vmax
16
Q
For the enzyme that displays Michaelis-Menten kinetics, the reaction velocity (as a fraction of vmax) observed at [S]=2 KM will be
A. 0.09
B. 0.33
C. 0.66
D. 0.91
A
C. 0.66
17
Q
When an excess of dry chlorine was passed over 1.12 g of heated iron, 3.25 g of a chloride of iron was obtained. What is the empirical formula of the chloride?
A. Fe3Cl
B. FeCl2
C. FeCl3
D. Fe2Cl6
A
C. FeCl3
18
Q
Which one of the following statements about a gas with the empirical formula NO2 must be correct?
A. it contains approximately 30% by mass of nitrogen
B. the mass of 22.4 liters of the gas at STP is 46 g
C. its relatively molecular mass is 46
D. One mole of gas contains 3 mol of atoms
A
A. it contains approximately 30% by mass of nitrogen
19
Q
The following table shows the specification of the composition of the feed, distillate, and bottoms of a distillation column (the components are listed in order of decreasing K-values):
Component Feed(mol%) Distillate(mol%) Bottoms(mol%)
Methane 25 41.74 -
Ethane - 8 13.36
Propane 26 43.11 0.44
n-Butane 18 1.79 42.11
n-Pentane 12 -
29.92
n-Hexane 11 - 27.43
Based on the preceding specification, the light key is
A. Methane
B. Ethane
C. Propane
D. n-Butane
A
C. Propane
20
Q
From the data in problem #1, the heavy key is
A. Propane
B. n-Butane
C. n-Pentane
D. n-Hexane
A
B. n-Butane
21
Q
From the data in problem #1, moles of distillate per 100 moles of feed are
A. 100
B. 59.9
C. 67.9
D. 20.7
A
B. 59.9
22
Q
From the data in problem #1, if the average relative volatility between the light key and heavy key is 1.98 the minimum number of stages including the reboiler as a stage is close to ____.
A. 12
B. 4
C. 6
D. 8
A
A. 12
23
Q
From the data in problem #1, if the specified separation requires 14 theoretical stages, the counting from the top, the location of the feed tray is close to ____.
A. 6
B. 3
C. 8
D. 9
A
A. 6
24
From the data in problem #1, the following data are available per 100 lbmols of feed/h (enthalpies are defined in this problem as the heat content of stream with reference to a chosen datum temperature):
Feed enthalpy = -4.772 E6 Btu/h Distillate enthalpy =-2.348E6 Btu/h
Bottoms enthalpy = -2.47E6 Btu/h External reflux ratio = 5
Latent heat of overhead vapor = 5556.5 Btu/lbmol
The reboiler duty for the specified feed rate in million btu/h is
A. 1.997
B. 1.945
C. 2.013
D. 2.105
B. 1.945
25
Moist air is found to contain 8.1 grains of water vapor per cubic foot at a temperature of 30°C. Calculate the temperature to which it must be heated in order that its relative saturation shall be 15%.
A. 50°C
B. 40°C
C. 57°C
D. 65°C
C. 57°C
26
What is the mass of the sphere of density 7500 kg/m3
which has the terminal velocity of 0.7 m/s in a large tank of water?
A. 0.066 g
B. 4.22 g
C. 0.00078 g
D. 1.28 g
A. 0.066 g
27
A liquid containing four components A, B, C, and D, with 0.3 mole fraction each of A, B and C, is to be continuously fractionated to give a top product of 0.9 mole fraction A and 0.1 mole fraction B. the bottoms are to contain not more than 0.5 mole fraction of A. Estimate the minimum reflux ratio required for this separation, if the relative volatility of A to B is 2.0.
A. 1.25
B. 4.58
C. 0.75
D. 2.71
D. 2.71
28
A pitot tube is used to measure the mean velocity in a pipe where water is flowing. A manometer containing mercury is connected to the
pitot tube and indicates a height of 150 mm. the specific weights of the water and mercury are 9810 N/m^3 and 133,400 N/m^3, respectively. Calculate the velocity of the water.
A. 6.09 m/s
B. 12.87 m/s
C. 18.42 m/s
D. 24.80 m/s
A. 6.09 m/s
29
How many stages and how much water is needed for the counter-current extraction of NaOH from a feed consisting of 80 lb NaOh, 400 lb H2O and 100 lb CaCO3. The final extract solution will contain 10% NaOh with the recovery of 95% of the NaOH . We shall set the underflow at a constant 3 lb solution/lb CaCO3.
A. 3
B. 7
C. 12
D. 8
A. 3
30
80 kg of water at 95°C is adiabatically mixed with 20 kg of cold water at 40°C. the entropy change for the process is closest to
A. 0.8473 kJ/K
B. 5.0 kJ/K
C. -0.8473 kJ/K
D. -5.0 kJ/K
A. 0.8473 kJ/K
31
What is the capacity in gpm of a clarifying centrifuge (cylindrical) operating at 1000 rpm, having a bowl diameter of 24 inches, liquid thickness of 3 inches, bowl depth of 16 inches and with no sedimentation thickness? The liquid has a viscosity of 3 cp, a specific gravity
of 1.3, bearing a solid having a specific gravity of 1.6. The cut size required is 30 microns.
A. 240 gpm
B. 280 gpm
C. 320 gpm
D. 360 gpm
D. 360 gpm
32
An insulated, electrically heated hot-water heater contains 190 kg of liquid water at 60°C when a power outage occurs. If water is withdrawn from the heater at a steady rate of m=0.2 kg/s, how long will it take for the temperature of the water in the tank to drop from 60 to 35°C? Assume that cold water enters the tank at 10°C, and that heat loses from the tank are negligible. Water may be considered an incompressible liquid.
A. 400.8 s
B. 658.5 s
C. 521.4 s
D. 844.3 s
B. 658.5 s
33
Glass spheres are fluidized by water at a velocity equal to one half of their terminal falling velocities. Calculate the density of fluidized bed in kg per m^3. The particles are 2 mm in diameter and have a density of 2500 kg/m^3. The density and viscosity of water are 1000 kg/m^3 and 1 mN-s/m^2, respectively.
A. 1367
B. 1100
C. 940
D. 825
A. 1367
34
From the data in problem #18, calculate the pressure gradient in the bed attributable to the presence of particles.
A. 3605 Pa/m
B. 4210 Pa/m
C. 4890 Pa/m
D.5120 Pa/m
A. 3605 Pa/m
35
A plate and frame press gave a total of 8 m^3 of filtrate in 1800 s and 11.3 m^3 in 3600 s when filtration was stopped. Estimate the washing time if 3 m^3 of wash water is used. The resistance of the cloth may be neglected and a constant pressure is used throughout.
A. 8400 s
B. 9880 s
C. 11240 s
D. 12448 s
A. 8400 s
36
Gaseous reactant A decomposes according to the reaction A → 3R (-rA=0.5 CA mole/L-min). The bed, 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?
A. 0.92
B. 0.86
C. 0.71
D. 0.65
C. 0.71
37
A 2.2 kW refrigerator or heat pump operates between -17°C and 38°C. the maximum theoretical heat that can be transferred from the cold reservoir is nearest to
A. 7.6 kW
B. 4.7 kW
C. 15.6 kW
D. 10.2 kW
D. 10.2 kW
38
A stream of gas at 70°F and 14.3 psia and 50% saturated with water vapor is passed through a drying tower where 90% of the water vapor is removed. Calculate the ponds of water removed per 1000 ft^3 of entering gas.
A. 0.0004 lb
B. 0.52 lb
C. 120 lb
D. 85 lb
B. 0.52 lb
39
A rotary countercurrent dyer is fed with ammonium nitrate containing 5% moisture at the rate of 1.5 kg/s, and discharges the nitrate with 0.2% moisture. The air enters at 405 K and leaves at 355 K; the humidity of the entering air being 0.007 kg moisture/kg dry air. The nitrate enters at 294 K and leaves at 339 K. neglecting radiation loses, calculate the mass of dry air passing through the dryer. Latent heat of water at 294K is 2450 kJ/kg-K. Specific heat capacity of ammonium nitrate is 1.88 kJ/kgK. specific heat capacity of dry air is 0.99 kJ/kg-K.
specific heat capacity of water vapor is 2.01 kJ/kg-K.
A. 6.1 kg/s
B. 8.4 kg/s
C. 4.2 kg/s
D. 10.4 kg/s
A. 6.1 kg/s
40
A rotary countercurrent dyer is fed with ammonium nitrate containing 5% moisture at the rate of 1.5 kg/s, and discharges the nitrate with 0.2% moisture. The air enters at 405 K and leaves at 355 K; the humidity of the entering air being 0.007 kg moisture/kg dry air. The nitrate enters at 294 K and leaves at 339 K. neglecting radiation loses, calculate the humidity of the air leaving the dryer. Latent heat of water at 294K is 2450 kJ/kg-K. specific heat capacity of ammonium nitrate is 1.88 kJ/kg-K. specific heat capacity of dry air is 0.99 kJ/kgK. specific heat capacity of water vapor is 2.01 kJ/kg-K.
A. 0.0188 kg/kg
B. 0.0844 kg/kg
C. 0.5410 kg/kg
D. 1.0051 kg/kg
A. 0.0188 kg/kg
41
Sulphuric acid is pumped at 3 kg/s through a 60 m length of smooth 25 mm pipe. Calculate the drop in pressure in kPa. Density of acid=1840 kg/m^3, viscosity of acid=25 mN-s/m^2.
A. 350
B. 840
C. 522
D.125
B. 840
42
Sulphuric acid is pumped at 3 kg/s through a 60 m length of smooth 25 mm pipe has an unknown pressure drop. If this pressure falls by one half, what will be the new Reynold's number? Density of acid=1840 kg/m^3, viscosity of acid=25 mN-s/m^2.
A. 3800
B. 4580
C. 7650
D. 5422
A. 3800
43
Sulphuric acid is pumped at 3 kg/s through a 60 m length of smooth 25 mm pipe has an unknown pressure drop. If this pressure falls by one half, what will be the new mass flow rate? Density of acid=1840 kg/m^3, viscosity of acid=25 mN-s/m^2.
A. 0.02 kg/s
B. 1.86 kg/s
C. 25.4 kg/s
D. 14.5 kg/s
B. 1.86 kg/s
44
What will be the terminal falling velocity of a particle of diameter 10 microns and of density 1600 kg/m^3
settling in a liquid of density 1000 kg/m^3 and of viscosity 0.001 Pa-s?
A. 0.033 mm/s
B. 0.00005 mm/s
C. 1.25 mm/s
D. 154 mm/s
A. 0.033 mm/s
45
From the data in problem #9, if Stokes law applies for particle Reynold's number up to 0.02, what is the diameter of the largest particle whose behavior is governed by Stokes law for this solid and liquid?
A. 10 microns
B. 85 microns
C. 380 microns
D. 540 microns
B. 85 microns
46
A solid material in a cube shape floats in oil of density 800 kg/m^3 with one-third of the block out of the oil. What is the buoyant force on the cube whose edge is 0.75 cm?
A. 2.207E-3 N
B. 1.255E-3 N
C. 2.581E-3 N
D. 3.012E-3 N
A. 2.207E-3 N
47
A block of wood that weighs 71.2 N and of specific gravity 0.72 is tied by a string to the bottom of a tank of water in order to have the block totally immersed. Determine the tension in the string.
A. 94.93 N
B. 23.73 N
C. 47.72 N
D. 50.25 N
B. 23.73 N
48
When one of the fluids is highly corrosive and has fouling tendency, it should
A. preferably flow inside the tube for its easier internal cleaning
B. preferably flow outside the tube
C. flow at very slow velocity
D. flow outside the tube when the flow is counter-current and inside the tube when the flow is co- current
A. preferably flow inside the tube for its easier internal cleaning
49
Optimum reflux ratio in a continuous distillation column is determined by the
A. maximum permissible vapor velocity
B. flooding limit of the column
C. total cost consideration (fixed cost of the column plus the cooling water and steam cost)
D. none of these
C. total cost consideration (fixed cost of the column plus the cooling water and steam cost)
50
High pressure fluid in a shell and tube heat exchanger should preferably be routed through the
A. tubes to avoid the expense of high pressure shell construction
B. shell side for smaller total pressure drop
C. shell side if the flow is counter-current and tube side if the flow is co-current
D. shell side for larger overall heat transfer coefficient
A. tubes to avoid the expense of high pressure shell construction
51
The percentage composition of a gaseous hydrocarbon is 85.62% C and 14.38% H. The density of this gas is 1.26 g/L at STP. Determine the formula of this hydrocarbon.
A. CH2
B. C2H4
C. C3H6
D. C4H8
B. C2H4
52
Sodium azide, NaN3 may be produced by the reaction: 3NaNH2 + NaNO3 → NaN3 + 3NaOH +NH3. If 5 grams of NaN3 is isolated from the reaction mixture, what percentage of the theoretical is obtained starting 15 grams of NaNH2?
A. 28.96%
B. 32.58%
C. 43.44%
D. 65.16%
D. 65.16%
53
The partial pressure of water in an air-water vapor mixture at 1 atm and 110°F is 50 mmHg. How much heat in BTU is required to raise the temperature of 10 lbs gas mixture to 220°F?
A. 93 BTU
B. 274 BTU
C. 418 BTU
D. 654 BTU
B. 274 BTU
54
For a superheated steam, the minimum number of property given to fixed its state is
A. 1
B. 2
C. 3
D. 4
B. 2
55
During a reversible process executed by a nonflow system, the pressure increases from 50 psia to 200 psia in accordance with PV=C, the internal energy increases 21.4 Btu; the initial volume is Vi=3 ft^3. Find the heat.
A. 17 Btu
B. 20 Btu
C. -17 Btu
D. -20 Btu
C. -17 Btu
56
Enthalpy of compressed air at 5 bar and 240 K in kJ/kg is
A. 238.5
B. 270.2
C. 280.4
D. 295.5
A. 238.5
57
The BPR of a 50% solution of NaOH at an evaporator pressure of 4.7 psia is
A. 73°F
B. 53°F
C. 85°F
D. 103°F
A. 73°F
58
One kg of water falls over a 100 m waterfall and lands in the pool at the bottom. This converts the potential energy it had at the top of the fall to internal energy. How much does the temperature of the water increase?
A. 0.12°F
B. 0.22°F
C. 0.42°F
D. 0.62°F
C. 0.42°F
59
Prandtl number of toluene at 60°C is
A. 2.0
B. 3.4
C. 4.8
D. 5.5
D. 5.5
60
How much heat is necessary to raise the temperature of 10 g of argon through 10°C at constant volume?
A. 5.5 cal
B. 12.5 cal
C. 7.5 cal
D. 14.0 cal
C. 7.5 cal
61
Water has its viscosity at 68°F equal to 0.01008 poise, what is the absolute viscosity in lb-s/ft2?
A. 2.11E-5
B. 3.12E-8
C. 1.22E-7
D. 4.13E-7
A. 2.11E-5
62
One hundred mole per hour of a 40% m solution of ethylene dichloride in toluene is fed into the middle of a distillation column. There is no net accumulation in the column; 100 mole/hr of total material leaves in two streams, an overhead or 'distillate' stream and a 'bottoms' stream. The distillate stream contains 95% m ethylene dichloride and the bottoms stream contains 10% m ethylene dichloride. What is the rate of flow of the distillate stream?
A. 64.7 mole/hr
B. 53.8 mole/hr
C. 35.3 mole/hr
D. 45.9 mole/hr
C. 35.3 mole/hr
63
An engine of a Mercedes-Benz automobile has an intake air of 20 C and compresses it adiabatically up to 10% of its initial volume. Considering the air as an ideal gas, find its final temperature at the end of the compression.
A. 736 K
B. 768 K
C. 878 K
D. 787 K
A. 736 K
64
A pump receives 8 kg/s of water at 220 kPa and 110°C and discharges it at 1100 kPa. Compute the power required in kW.
A. 8.126
B. 5.082
C. 7.014
D. 6.104
C. 7.014
65
Cv is given by
A. (∂U/∂T)V
B. (∂U/∂V)T
C. (∂U/∂P)V
D. (∂V/∂T)P
A. (∂U/∂T)V
66
Gibbs free energy (G) is defined as
A. G = U – TS
B. G = H – TS
C. G = H + TS
D. G = U + TS
B. G = H – TS
67
A solid body floats in a liquid with specific gravity 0.8 with 2/5 of its volume exposed to air. Its specific gravity is
A. 0.6
B. 0.48
C. 0.4
D. 0.32
B. 0.48
68
The critical speed of a ball mill in rpm whose diameter is 12 inches with grinding balls of diameter ½ in is approximately ____ rpm.
A. 60
B. 50
C. 90
D. 80
D. 80
69
A heat engine absorbs 1000 Btu at 800°F, and rejects heat at 100°F. the work done by the engine, if its efficiency is 50% of the Carnot efficiency is closest to
A. 150000 ft-lbf
B. 217000 ft-lbf
C. 440000 ft-lbf
D. 110000 ft-lbf
B. 217000 ft-lbf
70
A solution of NH4Cl is saturated at 70°C. Calculate the temperature to which this solution must be cooled in order to crystallize out 45% of the NH4Cl.
A. 9.5°C
B. 52.5°C
C. 40.7°C
D. 34.5°C
A. 9.5°C
71
For an ideal Otto engine operating on the air standard, the temperature at the end of isentropic compression is 840°F and at the end of expansion is 2540°F. The compression ratio is 7.5. Find the efficiency.
A. 34%
B. 48%
C. 67%
D. 82%
B. 48%
72
From the data in problem 36, find the work done by the cycle in Btu/lb of air.
A. 220
B. 442
C. 310
D. 570
B. 442
73
A storage tank at 100°F is part full of a liquid mixture which contains 50 mole percent n-butane and 50 mole percent n-pentane. The vapor space contains only butane and pentane vapors. What is the pressure in the vapor space?
A. 1.95 atm
B. 3.5 atm
C. 4.1 atm
D. 0.65 atm
A. 1.95 atm
74
From the data in problem#1, what is the mole fraction n-butane of the vapors?
A. 0.43
B. 0.65
C. 0.77
D. 0.93
C. 0.77
75
A still contains a liquor composition of o-xylene 10%, m-xylene 65%, p-xylene 17%, benzene 4% and ethyl benzene 4%. How many plates are required at total reflux to give a product of 80% m-xylene, and 14% p-xylene? The data are given as mass percent.
A. 30 plates
B. 39 plates
C. 53 plates
D. 60 plates
B. 39 plates
76
An ideal mixture f A and B is to be distilled continuously. If the relative volatility is constant at 1.75 and
Feed = saturated liquid with 50 mol%, A feed rate = 200 lbmol/hr, Distillation composition = 90%A, bottoms composition =10% A, find the minimum number of theoretical stages.
A. 7
B. 3
C. 10
D. 15
A. 7
77
The distance between plates is y= 0.5 cm, v = 10 cm/s and the fluid is ethyl alcohol at 273 K having a viscosity of 1.77 cp. Calculate the shear stress in dyne/cm2.
A. 0.210
B. 0.354
C. 0.540
D. 0.720
B. 0.354
78
What head, in meters of air, at ambient conditions of 100 kPa and 20°C is equivalent to 15 kPa?
A. 49
B. 131
C. 257
D. 1282
D. 1282
79
Calculate the pressure drop when 3 kg/s of sulphuric acid flows through 60 m of 25 mm pipe (density=1840 kg/m^3, viscosity=0.025 Pa-s).
A. 210 kPa
B. 442 kPa
C. 755 kPa
D. 900 kPa
D. 900 kPa
80
The unit-lateral deformation of a body under stress divided by the unit longitudinal deformation is known as
A. Poisson's ratio
B. Hooke's law
C. Euler's ratio
D. Mohr modulus
A. Poisson's ratio
81
Le/D for fully open globe valve may be around
A. 10
B. 25
C. 75
D. 300
D. 300
82
What is the porosity of a solid if its bulk density = 1125 kg/m^3 and its true density is 1500 kg/m^3?
A. 0.25
B. 0.75
C. 1.33
D. 0.33
A. 0.25
83
What alloying element is added in stainless steel to impart corrosion resistance?
A. chromium
B. vanadium
C. titanium
D. copper
A. chromium
84
It is equal to the gross annual sales divided by the fixed capital investment.
A. turnover ratio
B. capital ratio
C. investment ratio
D. acid ratio
A. turnover ratio
85
A replica of a commercial scale plant.
A. lab scale
B. bench scale
C. pilot scale
D. small scale
C. pilot scale
86
Prandtl number of toluene at 60°C is
A. 2.0
B. 3.4
C. 4.8
D. 5.5
D. 5.5
87
High pressure fluid in a shell and tube heat exchanger should preferably be routed through the
A. tubes to avoid the expense of high pressure shell construction
B. shell side for smaller total pressure drop
C. shell side if the flow is counter-current and tube side if the flow is co-current
D. shell side for larger overall heat transfer coefficient
A. tubes to avoid the expense of high pressure shell construction
88
When one of the fluids id highly corrosive and has fouling tendency , it should
A. preferably flow inside the tube for its easier internal cleaning
B. preferably flow outside the tube
C. flow at very slow velocity
D. flow outside the tube when the flow is counter-current and inside the tube when the flow is co-current
A. preferably flow inside the tube for its easier internal cleaning
89
The viscosity of 40% by weight sucrose in water at 20°C in centipoises is
A. 5.026
B. 6.223
C. 7.499
D. 56.7
B. 6.223
90
The boiling point of 60% H2SO4(aq)
A. 250°F
B. 280°F
C. 300°F
D. 305°F
B. 280°F
91
Which of the following does not belong to the group?
A. rougher
B. classifier
C.scavenger/recleaner
D. cleaner
B. classifier
92
A dimensionless number which is the ratio of the characteristic relaxation time of the fluid and the characteristic time scale of flow.
A. Deborah number
B. Peclet number
C. Grashof number
D. Froude number
A. Deborah number
93
Two streams are mixed to form a single stream. Only the flow in the mixed stream is known. A soluble salt is added to one of the original streams at a steady state and samples of this stream show it to be 4.76% salt by weight. Samples of the combined stream show it to be 0.62% by weight. What is the flow ratio of the two original streams?
A. 2.3
B. 4.5
C. 6.7
D. 9.8
C. 6.7
94
Tung meal contain 55% oil is to be extracted at the rate of 4000 lb/hr using n-hexane containing 5% oil as solvent. A countercurrent multiple stage extraction system is to be used. the meal retains 2 lb of solvent/lb of oil free meal while the residual charge contain 0.11 lb oil/lb oil free meal while the product is composed of 15% oil. The theoretical number of ideal stages is
A. 3
B. 4
C. 5
D. 6
B. 4
95
Suppose we dilute 1 lb of 50 wt% NaOH solution at 70°F with 1 lb of pure water, also at 70°F. What is the final temperature if the mixing is adiabatic?
A. 123°F
B. 100V
C. 92°F
D. 85°F
A. 123°F
96
During a reversible process executed by a non-flow system, the pressure increases from 50 psia to 200 psia in accordance with PV=C, the internal energy increases 21.4 Btu; the initial volume is Vi=3 ft^3. Find the heat.
A. 17 Btu
B. 20 Btu
C. -17 Btu
D. -20 Btu
C. -17 Btu
97
A pump receives 8 kg/s of water at 220 kPa and 110°C and discharges it at 1100 kPa. Compute the power required in kW.
A. 8.126
B. 5.082
C. 7.014
D. 6.104
C. 7.014
98
Estimate the necessary wall thickness for a horizontal cylindrical pressure vessel with a diameter of 10 ft, a working pressure of 250 psig and a design tensile stress of 20,000 psig.
A. 1.90 cm
B. 2.70 cm
C. 2.30 cm
D. 2.50 cm
A. 1.90 cm
99
In a batch process, 100 lb of carbon monoxide gas are compressed adiabatically from 80°F and 15 psia to a final temperature of 600°F. If the gas is considered to be ideal, calculate the compression in Btu.
A. 1200
B. 4100
C. 5800
D. 9300
D. 9300
100
In a batch process, 100 lb of carbon monoxide gas are compressed adiabatically from 80°F and 15 psia to a final temperature of 600°F. If the gas is considered to be ideal, calculate the final pressure if the pressure is reversible.
A. 20 psia
B. 171 psia
C. 48 psia
D. 520 psia
B. 171 psia
101
During a reversible steady flow process by 5 lb/sec of air, the pressure remains constant at p=50 psia and the temperature increases 300°F. What is the change in total volume of the air in ft^3/s?
A. 0.75
B. 11.11
C. 87.5
D. 97.1
B. 11.11
102
The work required to compress a gas reversibly according to pV1.30=constant is 50,000 ftlb if there is no flow. Determine the change in internal energy if the gas is air.
A. 48.2 Btu
B. 2.45 Btu
C. 121 Btu
D. 187 Btu
A. 48.2 Btu
103
Water is flowing through a pipe. A pitot-static gage registers 3.0 in. of mercury. What is the velocity of the water in the pipe?
A. 2.85 m/s
B. 4.33 m/s
C. 3.86 m/s
D. 5.72 m/s
B. 4.33 m/s
104
A 70°C aqueous solution initially containing 15 mol% KNO3 is to be boiled so as to give a final yield of solid KNO3 of 60%. How much (in % of initial water content) of the initial water must be boiled off?
A. 30%
B. 45%
C. 60%
D. 72%
D. 72%
105
At the fertilizer plant drier, the special formula 14-14-14, requires the removal of 200 lbs of water per hour to assure good granulation. Air at 70°F and 50% relative humidity enters the drier and leaves at 140°F and 80% relative humidity. What is the weight of the bone-dry air used per hour? Assume barometer reading at 760 mmHg.
A. 18.09 lbd.a/hr
B. 180.9 lbd.a/hr
C. 1809 lbd.a/hr
D. 10890 lbd.a/hr
C. 1809 lbd.a/hr
106
Petroleum oil of specific gravity of 0.9 and viscosity 13 centipoises flows isothermally through a horizontal sch 40, 3-in pipe. A pitot tube is inserted at the center of the pipe, and its lead are filled with the same oil and attached to a U-tube containing water. The reading on the manometer is 3 ft. calculate the volumetric flow of oil (ft^3/min).
A. 0.11
B. 1.12
C. 11.12
D. 112
C. 11.12
107
Two pound air is compressed from 20 psia to 200 psia while maintaining the temperature constant at 100°F. Calculate the heat transfer needed to accomplish this process.
A. -176.7 Btu
B. -180.6 Btu
C. -182.1 Btu
D. -185.8 Btu
A. -176.7 Btu
108
Shape factor for a cylinder whose length equals its diameter is
A. 1.5
B. 0.5
C. 1
D. 0
A. 1.5
109
A gasoline engine in a bus takes in 10 kJ of heat and delivers 2 kJ of mechanical work per cycle. Compute the efficiency of the engine if heat is obtained by burning gasoline with a heating value of 50000 kJ/kg.
A. 20%
B. 30%
C. 40%
D. 17%
A. 20%
110
NaSO4.H2O crystals are formed by cooling 100 kg of 30% by weight aqueous solution of Na SO4. The final concentration of the solute in the solution is 10%. The weight of the crystals is
A. 22.33 kg
B. 32.2 kg
C. 45.35 kg
D. 58.65 kg
D. 58.65 kg
111
Pressure drop due to pipe fittings can be estimated by p/p = 4f (L/D) (V2
/2gc) where Le = equivalent length of straight pipeline which will incur the same frictional loss as the fitting and D= diameter of the fitting. The value of the Le/D (dimensionless) for 45° elbow and 180°
close return bends would be respectively around
A. 5 and 10
B. 45 and 75
C. 180 and 300
D. 300 and 500
B. 45 and 75
112
Critical pressure of nitrogen.
A. 65 atm
B. 33.5 atm
C. 100 atm
D. 62.5 atm
B. 33.5 atm
113
Compressibility factor for oxygen at 140 K and 80 bar
A. 0.1940
B. 0.2969
C. 0.2527
D. 0.3099
C. 0.2527
114
Emissivity of sandstone is
A. 0.23
B. 0.59
C. 0.78
D. 0.90
B. 0.59
115
Air enters at a rate of 20 kmol/min in a vessel that contains 10 m^3 liquid hexane at 20°C. The leaving gas mixture contains 91% hexane. How long it takes to vaporize or absorb all the hexane in the vessel?
A. about 0.5 min
B. about 1 hr
C. about 0.5 hr
D. about 20 min
A. about 0.5 min
116
Fresh orange juice contains 12.0 wt% solids. Initially a single evaporation process was used for the concentration to 45%, but volatile constituents of the juice escaped with the water, leaving the concentration with a flat taste. The present process overcomes this problem by passing the evaporator with a fraction of the fresh juice; the juice that enters the evaporator is concentrated to 58% solids, the product is mixed with the bypassed fresh juice to achieve the desired final concentration of solids. Calculate the fraction of the feed that by passed the evaporator.
A. 5% bypass
B. 10% bypass
C. 15% bypass
D. 30% bypass
B. 10% bypass
117
It is the residue for the destructive distillation of wood.
A. shale oil
B. charcoal
C. bagasse
D. char
B. charcoal
118
Orsat analysis of the stack gas from the combustion of the gaseous mixture of ethane and methane shows 10.57% CO2, 3.79% O2 and the rest N2. The air enters at 30°C and the barometer reads 760 mmHg. If the partial pressure of water in the stack gas is 127 mmHg, what is the relative humidity of the incoming air?
A. 88%
B. 80%
C. 70%
D. 66%
A. 88%
119
Flooding in a column results due to
A. high pressure drop
B. low velocity of the liquid
C. low pressure drop
D. high temperature
A. high pressure drop
120
If 150 L of nitrogen gas (n=1.4) expands adiabatically starting at a pressure of 1 atm and the final volume is 250 L, what is the final
pressure?
A. 0.43 atm
B. 0.51 atm
C. 0.49 atm
D. 0.58 atm
C. 0.49 atm
121
During an isentropic expansion of air, the volume triples. If the initial temperature is 200°C, what is the final temperature in °C?
A. 28.5
B. 31.8
C. 26.4
D. 34.9
B. 31.8
122
Pine oil is used in froth flotation technique acts as a
A. collector
B. frother
C. modifier
D. activator
B. frother
123
A PFR operating isothermally at 773 K is used to conduct the following reactions:
Methylacetoxipropionate → acetic acid + methyl acrylate if a feed of pure methylacetoxipropionate enters at 5 atm and at a flow rate of 0.193 ft^3/s, what length of pipe with a cross sectional area of 0.0388 ft^2 is necessary for the reaction to achieve 90% conversion? Data: κ = 7.8 x 10^9
exp[ -19, 200/T]s-1
A. 110 ft
B. 122 ft
C.134 ft
D. 149 ft
D. 149 ft
124
A boiler is fired with a coal containing 75% carbon and 8 percent ash, burned under such conditions that the elimination of combustible matter from the refuse is complete. The air enters the furnace at 90°F with a relative humidity of 80%. The vapor pressure of water at 90°F is 36mmHg. The flue gas go to the stack gas at 380°F. The average flue gas analysis shows 12.6% CO2, 6.2% O2 and 1% CO. Calculate the percent excess air.
A. 25.4%
B. 32.8%
C. 41.5%
D. 48.7%
C. 41.5%
125
From the data in problem #9, calculate the % oxygen in the fuel.
A. 5.1%
B.11.9%
C. 18.5%
D. 22.7%
B.11.9%
126
From the data in problem #9, calculate the cubic feet of stack gas per pound of coal.
A. 355 ft^3
B. 388 ft^3
C. 418 ft^3
D. 450 ft^3
C. 418 ft^3
127
From the data in problem #9, calculate the cubic feet of air per pound of coal.
A. 165 ft^3
B. 195 ft^3
C. 210 ft^3
D. 245 ft^3
B. 195 ft^3
128
A solution of sodium chloride in water is saturated at a temperature of 15°C. Calculate the weight of NaCl that can be dissolved by 100 lb of this solution if it is heated to a temperature of 65°C.
A. 0.08 lb
B. 1.1 lb
C. 2.2 lb
D. 3.0 lb
B. 1.1 lb
129
Water is used to absorb ammonia from a gas mixture in a single separation stage contactor. The process is schematically represented in the figure below,
If the stage is ideal, then the value of y is
A. 1/15
B. 1/10
C.2/15
D.1/6
A. 1/15
130
It is the tendency of a material to break into smaller sizes in the course of handling.
A. brittleness
B. hardness
C. friability
D. toughness
C. friability
131
It is defined as the total surface of a unit weight or volume of a solid.
A. surface area
B. specific surface
C. specific volume
D. particle size
B. specific surface
132
In size reduction, the ratio of the average diameter of the feed to the average diameter of the product is the
A. settling ratio
B. diameter ratio
C. reduction ratio
D. classification ratio
C. reduction ratio
133
Which of the following is a soft material?
A. quartz
B. topaz
C. sapphire
D. gypsum
D. gypsum
134
A classification technique where materials of equivalent size are separated according to their densities.
A. sizing
B. screening
C. sedimentation
D. sorting
D. sorting
