MOCK BOARD EXAMINATION: CHEMICAL ENGINEERING PRINCIPLES
1.
What type of pump would you recommend if the capacity is 5000 gpm at a head of 15 ft of water?
a. gear pump b. screw pump c. centrifugal pump d. axial flow pump A pump delivers 40 gpm of water water with a total head of 40 ft. ft. The efficiency of the pump is 65%. What is its BHP? a. 0.62 b. 0.70 c. 0.92 d. 0.89 3. A flotation modifier which assists in selectivity or stop unwanted minerals from floating is a. activators b. promoters c. depressants d. regulators 4. Determine the enthalpy in the final state in English units when 2 lbm of saturated liquid mercury at 1 psia is mixed with 4 lbm of mercury vapor at 1 psia and 1400 oF. During the process, the pressure in the cylinder is kept constant and no energy is lost between the cylinder and mercury. a. 114 b. 122 c. 131 d. 150 5. Based from the previous number, determine the final state of the mixture. a. 0.45 b. 0.55 c. 0.21 d. 0.79 o 6. Steam at 3 MPa, 300 C leaves the boiler and enters the high-pressure turbine ( in a reheat cycle) and is expanded to 300 kPa. The steam is then reheated to 300 oC and expanded in the second stage turbine to 10 kPa. What is the efficiency of the cycle if it is assumed to be internally reversible? a. 0.317 b. 0.218 c. 0.525 d. 0.871 7. A container which has a volume of 0.1 m3 is fitted with a plunger enclosing 0.5 kg of steam at 0.4 MPa. Calculate the amount of heat transferred when the steam is heated to 300 oC at constant pressure. a. 680.1 kJ b. 91.0 kJ c. 771.1 kJ d. 2,804.8 kJ 8. From the previous question, what was the work done by the system? a. 771 kJ b. 680 kJ c. 91 kJ d. 604 kJ 9. Water at 200 oF is pumped from a storage tank at the rate of 50 gal/min. The motor for the pump supplies work at the rate of 2 hP. The water goes through a heat exchanger, giving up heat at the rate of 40000 BTU/min, and is delivered to a second storage tank at an elevation of 50 ft above the first tank. What is the temperature of the water delivered to the seco nd tank? The density of water of water at 200 oF is 60.1 lmm/ft3. a. 100.75 oF b. 132 oF c. 112.75 oF d. 97 oF 10. A central power plant, rated at 800,000 kW, generates steam at 585 K and discards heat to a river at 295 K. If the thermal efficiency of the plant is 70% of the maximum possible value, how much heat is discarded to the river at rated power? a. -1.960 x 10 6 kW b. 1.891 x 106 kW c. -1.505 x 106 kW d. 1.008 x 106 kW 11. The differential height between two points where a fluid has to be transferred is the 2.
a. potential head b. pressure head c. velocity head d. dynamic head 12. Venturi meters, orifice meters and pitot tubes are called a. area meters b. electronic meters c. variable head meter d. constant pressure meters 13. Wet solid is to be dried from 40% to 10% moisture in 5 hours under CDC. The critical moisture content is 20% and the equilibrium moisture content is 7%. All moisture contents are on dry basis. basis. Determine the time in hours needed needed to dry from 22% db to 12% db. a. 1.85 b. 2.73 c. 3.89 d. 6.25 14. A venturi meter is to be installed in a 100 mm line to measure the flow of water at 150C. The maximum flowrate flowrate is 75 m3/h. the manometer manometer reading is 1.25 m of Hg. What will be the power in kW kW required to operate the meter meter at full load? a. 1.26 b. 1.07 c. 0.55 d. 0.32 15. An equimolal mixture of benzene and toluene is subjected to flash distillation at a separator pressure of 1 atm. If 60% of the charge is vaporized, what is the concentration of the distillate in mol% benzene? a. 36.5 b. 42.1 c. 58.5 d. 66.9 16. Product S is formed according to the liquid phase reaction: AS with –rA=kCA and k=2/min. A stream containing 5 mols/L mols/L of A is available at Php10/L. The product is sold at Php2.5/mol. Operating cost is Php10/day and no recycling of unreacted A can be sold. Given a backmix reactor, the conversion of A that should be used to have the maximum profit/day is a. 78 % b. 84 % c. 89 % 17. The undesirable material that is separated from an ore during the concentration process is called
d. 98 %
a. gangue b. leachate c. slag d. refuse 18. A frequency response measure of how well the system responds to variations in the a. feed back b. dead time c. control system d. band width 19. Which of the following is an undesirable dynamic characteristic of an instrument? a. reproducibility b. static error c. dead zone d. time lag 20. The spectral distribution of a p erfect emitter has maximum value and that the corresponding wavelength depends o n temperature. This theory is stated by a. Wien’s Law b. Kirchoff’s Law c. Planck’s Law d. Stefan-Boltzman Stefan-Boltzman Law 21. Chemical name of sal soda
MOCK BOARD EXAMINATION: CHEMICAL ENGINEERING PRINCIPLES
a. sodium bicarbonate b. sodium carbonate c. sodium hypochlorite d. sodium chloride 22. When ΔH = Q, the process is a. isochoric b. isothermal c. adiabatic d. isobaric 23. For the completely corrosion resistant stainless steel, the minimum % of chromium in the alloy required is a. 1.1 % b. 3.2 % c. 8.3 % d. 11 % 24. Who among the following scientists had no contributions to the emergence of the l aws of thermodynamics? a. William Thomson b. Rudolf Clausius c. Otto Hahn d. William Rankine 25. Fischer-Tropsch method aims at a. gasification of coal b. hydrogenation of coal c. synthesis of gasoline d. catalyzation of diesel 3 3 26. The characteristic diameter of a solid particle where the volume is 10 cm , surface area of 15 cm and shape factor of 1.2 is ________. a. 0.67 cm b. 1.5 cm c. 2.67 cm d. 4.8 cm 27. Drum driers are used for drying a. slurries b. pharmaceutical c. gases 28. An adsorption phenomenon where the mechanism of adsorption is electrostatic.
d. pastes
a. GAC b. Ion exchange c. Electrodialysis d. RO 29. A steel rod on a bridge must be made to withstand a pull of 5000 lbs. Find the diameter of the rod assuming a factor of safety of 5 and ultimate stress of 64,000 psi. a. 0.71 “ b. 0.84 “ c. 0.75 “ d. 0.81 “ 30. Fogging is a result of a condition where by the gas becomes a. saturated with vapor b. unsaturated with vapor c. liquid due to cooling d. supersaturated with vapor 31. Shear stress increases with time at constant shear rate. a. dilatant b. pseudoplastic c. thixotropic d. rheopectic 32. If a centrifuge is 3 ft diameter and rotates at 1000 rpm, the speed (rpm) of a laboratory centrifuge of 6 inch diameter be run if it is to duplicate the plant conditions is a. 2449 b. 2500 c. 2469 d. 2100 33. Valves were pressure drop is large a. gate b. globe c. check d. butterfly 34. Fittings that join two streams to form a third stream or for branch connections a. plugs b. reducers c. tees d. union 35. When the ID of the pipe through which a fluid flows is doubled, the pressure loss due to friction per unit length of pipe and for the same volumetric flowrate is changed by approximately factor of a. 1/8 b. 1/16 c. 1/32 d. 1/64 36. The upper plate is fixed, while the lower plate moves in the positive x direction at 0.5 m/s. The plate separation is 0.001 m, the fluid viscosity is 0.7 cP and the velocity profile is linear. Calculate the shear stress in the moving fluid. a. 0.05 Pa b. 0.15 Pa c. 0.25 Pa d. 0.35 Pa 37. A centrifuge bowl is spinning at a constant speed of 2000 rpm. The radius of the bowl in cm needed to create a force of 455 g is a. 10.2 b. 12.0 c. 5.8 d. 8.5 38. Air at 30OC and 5 bars is flowing inside a 1/2 inch steel pipe and has a viscosity of 1.8685 x 10-6 Pa-s. If the flow is 4 SCFM, what will be the Re? a. 1.31 x 104 b. 3.91 x 105 c. 5.31 x 104 d. 6.53 x 105 39. A water storage tank assumes the supply of water into a factory. Water is supplied to the tank through a booster pump installed in the water line. The theoretical pump horsepower required by the system is 3.25 hp. What is the 30 day operating cost of the pump if electric power cost on the average is PhP 3.73/kWh. The pump is 65% efficient and operates for 12 hrs a day. a. Php 3700 b. Php 5000 c. Php 2116 d. Php 7000 40. Consider a laminar flow of fluid through a straight horizontal pipe. What will be the effect on pressure drop of doubling both the pipe diameter and volumetric flow rate, assuming other quantities constant? a. it will decrease by 8 b. it will increase by 16 c. it will increase by 4 d. it will not change 41. The treatment of a material containing a natural amount of moisture or a material that has been dried before screening a. absorption b. dry screening c. wet screening d. grinding 42. Yields very fine products from soft ,non-abrasive materials particles are rubbed against each other and against a rigid surface a. compression b. impact c. attrition d. cutting 43. The condition at which the balls are carried over due to very high speed a. agitating b. centrifuging c. rotating d. mixing 44. The angle of maximum slope measured from the horizontal at which a heap of loose solid material will stand without sliding a. angle of inclination b. angle of slide c. angle of repose d. angle of rotation o 45. An apple loses 4.5 kJ of heat as it cools per C drop in its temperature. The amount of heat loss f rom the apple peroF drop in its temperature is
MOCK BOARD EXAMINATION: CHEMICAL ENGINEERING PRINCIPLES
a. 1.25 kJ b. 2.50 kJ c. 5.0 kJ d. 4.1 kJ 46. Coal fired in a furnace has a heating value of 13800 BTU/lb and contains 78.05% C and 1.2% S. The proximate analysis shows 4% M, 24% FC, 8% ash and the analysis of the refuse shows 8% VCM, 25% FCM and 32% ash. Calculate the % of C lost in the ref use. a. 4.22 % b. 9.5 % c. 17 % d. 8 % 47. How long could a 2000 hP motor be operated on the heat energy liberated by 1 m3 of ocean water when the temperature of the water is lowered by 1 oC and if all these heat were converted to mechanical energy? a. 371.56 yrs b. 245.65 yrs c. 210.92 yrs d. 177.42 yrs 48. The equation that is applied to describe the flow of a fluid through porous medium under laminar condition is a. Fanning-Darcy b. Ruth c. Karman-Kozeny d. Hagen-Poiseuille 49. The bursting pressure of a pipe is directly proportional to its a. schedule number b. inside diameter c. outside diameter d. length 50. Which of the following is the commonly used polymer type resin in ion exchange? a. acetylene b. polyethylene c. polystyrene d. polypropylene 51. A discrete output system. a. SCADA b. binary system c. PLC d. cascade 52. A human being (75kg) consumes about 6000 kJ of food per day. Assume that the food is all glucose and that the overall reaction is C6H12O6 + 6O2 → 6CO2 + 6H2O, - ∆Hr = 2816 kJ. Find man’s metabolic rate (the rate of living, loving amd laughing) in terms of moles of oxygen used per m3 of person per second. a. 0.001 b. 0.002 c. 0.005 d. 0.050 o o 53. A 10-cm diameter copper ball is to be heated from 100 C to an average temperature of 150 C in 30 minutes. Taking the average density and specific heat of copper in this temperature range to be 8950 kg/m3 and 0.395 kJ/kg-oC respectively. Determine the total amount of heat transfer to the copper ball. a. 46.9 kJ b. 78.1 kJ c. 92.6 kJ d. 98.4 kJ 54. Based on the previous problem, the average rate of heat transfer to the ball is a. 51.5 W b. 98.4 W c. 62.9 W d. 78.1 W 2 55. Calculate the average heat flux of the system, in W/m (refer to nos. 53 and 54) a. 1636 b. 1874 c. 2100 d. 2750 56. What is the ratio of output amplitude to input amplitude for a sinusoidal forcing function in a first order system? a. 2 b. 1 c. <1 d. >1 57. Phase lag of the sinusoidal response of a first order system a. 30 O b. 90 0 c. 120 0 d. 180 0 58. Pressure of 0.01 psi (absolute) can be measured by a. Ionization gauge b. Pirani gauge c. Bourdon gauge d. Mclead gauge 59. Fluid passes through the reactor with no mixing of earlier and later entering fluid, and with no overtaking. a. Batch reactor b. Plug flow reactor c. Mixed flow reactor d. Semi-batch reactor 60. A measure of the ability of a material to conduct heat a. thermal conductivity b. diffusivity c. specific heat d. heat capacity 61. Stalagmometer is used f or the measurement of a. kinematic viscosity b. c. d. 62. In an exothermic chemical reactor, the manipulated variable is the flow rate of a. coolant b. product c. reactant d. hot fluid 63. The integral of a unit step function is also known as a. parabolic function b. unit ramp function c. unit impulse function d. sinusoidal function 64. If G = insoluble gas in gas stream and L = non-volatile solvent in liquid stream, then the slope of the operating line for the absorber is a. always < 1 b. >1 c. G/L d. L/G 65. Diameter of raschig rings used in packed tower in industry is normally around a. 2” b. 4” c. 8” d. 12” 66. When both the fluids flow concurrently in an absorber, the slope of the operating line is a. negative b. positive c. 1 d. -1 67. The number of molecules involved in the reaction, and this has been found to have the values of one, two or occasionally three. a. selectivity b. molecularity c. yield d. dependency 68. A binary mixture of 5 moles of benzene and 9 moles toluene will boil at . a. 110 OC b. 105 OC c. 102 OC d. 99 OC 69. A homogeneous gas reaction A → 3R has a reported rate at 215 oC, -rA = 10-2CA1/2 [mol/L-s]. Find the space time needed for 80% conver sion of a 50% A – 50% inert feed to a plug flow reactor operating at 215 oC and 5 atm (CAO = 0.0625 mol/liter) a. 13.28 s b. 33.21 s c. 27.88 s d. 41.51 s
MOCK BOARD EXAMINATION: CHEMICAL ENGINEERING PRINCIPLES
70. 1.2 kg of liquid water initially at 15 oC is to be heated to 95 OC in a teapot equipped with a 1200-W electric heating element inside. The teapot is 0.5 kg and has an average specific heat of 0.7 kJ/kg-oC. Disregarding any heat loss from the teapot, determine how long it will take for the water to be heated. a. 6 min b. 400 s c. 8 min d. 350 s 71. What is the dew point of a equimolar mixture of benzene and toluene at 101.3 kN/m2 ? a. 355 K b. 364 K c. 372 K d. 375 K 72. The vapour pressures of n-heptane and toluene at 373K are 106 and 73.7kN/m2 respectively. What is the mole fractions of n-heptane in the vapor phase at 373K if the total pressure is 101.3kN/m2? a. 0.856 b. 0.896 c. 0.942 d. 0.964 73. The plate on which the feed in introduced is known as a. rectifier b. condenser c. reboiler d. feed plate 74. At a temperature of 366.4K, the vapor pressure of n-hexane and octane are 1480 and 278 mm Hg, respectively. Assume the hexaneoctane system obeys Raoult’s Law and the total pressure is 1 atm. Calculate the equilibrium liquid composition in mole fraction of the more volatile component. a. 0.24 b. 0.40 c. 0.65 d. 0.78 75. The transfer of energy from the more energetic particles of a substance to the adjacent less energetic ones as a result of intersections between the particles. a. conduction b. convection c. radiation d. all of the given 76. One hundred moles per hour of solution containing 80 moles of A, the rest B is subjected to a simple continuous distillation. D moles of distillate containing 72 moles A is obtained. If A is five times more volatile than B, the concentration of A in the distillate is a. 0.55 b. 0.75 c. 0.85 d. 0.95 77. What is the relative volatility of benzene to pentane at 1000F and 465 psia? a. 15.2 b. 0.75 c. 3.2 d. 0.30 78. The charge to a simple batch still consists of an equimolar mixture of hexane and heptanes. If the relative volatility of hexane and heptanes is 2 and 50% hexane has vaporized, what is the mole fraction of heptanes in the total distillate? a. 0.37 b. 0.46 c. 0.52 d. 0.73 79. Solvent used in extractive distillation a. is of low volatility c. forms a high boiling azeotrope b. forms a low boiling azeotrope d. does not alter the volatility of the compound 80. A mixture of ammonia and air at a pressure of 745 mm Hg and a temperature of 400C contains 4.9% NH3 by volume. The gas phase at a rate of 100 cfm through an absorption tower in which only ammonia is removed. The gases leave the tower at a pressure of 740 mm Hg, a temperature of 200C and contain 0.13% ammonia by volume. Calculate the rate of flow of gas leaving the tower in cfm. a. 89.5 b. 98.2 c. 107.7 d. 122.9 81. A homogeneous reaction wherein the rate of change of any reactant A is independent of the concentration of materials a. zero-order b. first-order c. second-order d. pseudo first-order 82. The mole fraction of solute entering a gas absorber is 0.25. if the percentage recovery is 75 percent , the mole fraction of the solute leaving the tower will be a. 0.0625 b. 0.0769 c. 0.0833 d. 0.1570 83. In case of an absorber, the operating a. line can be either above or below the equilibrium curve c. line always lies below the equilibrium curve b. velocity is more than the loading velocity d. line always lies above the equilibrium curve 84. Mascagnite is an odorless white crystalline salt, which is used in fertilizers, fire retardants, and water purification. What is its chemical formula? a. (NH4)2SO4 b. CH2NH4 c. (NH4)SO3 d. CH3COOH 85. What is the collection efficiency in a 14 inch diameter by 6 inch thick bed of 1/2 –in Intalox saddles, if the fuel-oil mist particle being collected is 1 micron diameter at a 30 ft/s gas velocity a. 0.98 b. 0.87 c. 0.81 d. 0.70 LINKAGE PROBLEM for Nos. 86 to 88 Consider a feed CAO = 100, CBO = 200, CiO = 100 to a steady-flow reactor. The isothermal gas-phase reaction is A + 3B → 6R; If C A = 40 at the reactor exit 86. What is CB? a. 25 b. 40 c. 45 d. 55 87. Calculate for XA a. 0.25 b. 0.50 c. 0.75 d. 1.0 88. Determine XB a. 0.25 b. 0.50 c. 0.75 d. 1.0 89. What is the Fanning friction factor for a 20 mm ID galvanized iron pipe if the NRe of ethanol flowing is 3.0 x 104? a. 0.0093 b. 0.0089 c. 0.0120 d. 0.0920
MOCK BOARD EXAMINATION: CHEMICAL ENGINEERING PRINCIPLES
90. Which one of the following pipes has the highest relative roughness? a. 5" diameter Concrete b. 3" diameter Wrought iron c. 8" diameter Drawn tubing d. 1" diameter Riveted steel pipe pipe 91. Designing CAPEX process plant projects usually involves 4 phases. At what stage does the feasibility phase occur a. FEL-1 b. FEL-2 c. FEL-3 d. EPC 92. Consider the aqueous reactions,
For 90 % conversion of A, find the concentration of R in the product stream using PFR. Equal volumetric flow rates of the A and of B streams are fed to the reactor, and each stream has a concentration of 20 mol/L of reactant. a. 2.86 b. 6.14 c. 0.5 d. 4.5 93. From the previous number, calculate for the concentration of R using a mixed flow reactor. a. 6.14 b. 1.15 c. 4.5 d. 7.85 94. Estimate the BPR (boiling point rise) of a 10% aqueous KOH solution at 1 atm a. 4 oF b. 3 oF c. 5 oF d. 6 oF 95. A thermometer at 0oC is immersed in boiling water. What will be the time constant of the system if the temperature reading becomes 860C after 2 secs. a. 2.14 min b. 1.90 min c. 2.33 min d. 1.89 min 96. What is the typical over-all HTC in a tubular HE where kerosene flows in the shell side and water in the tube side? a. 25 to 50 b. 30 to 65 c. 20 to 45 d. 35 to 60 97. The roof of an electrically heated home is 6m long, 8m wide and 0.25 m thick, and is made of a flat layer of concrete whose thermal conductivity is 0.8 W/m-oC. The temperatures of the inner and the outer surfaces of the roof one night are measured to be 15 oC and 4 oC, respectively, for a period of 10 hours. Determine the rate of h eat loss through the roof that night. a. 1690 W b. 1540 W c. 1350 W d. 1090 W 98. Referring to the cost of that heat loss to the home owner if the cost of electricity is %0.08/ kWh. a. $ 1.69 b. $ 1.54 c. $ 1.35 d. $ 1.71 99. Flow with no component of velocity in any other direction but in the flow direction a. laminar flow b. turbulent flow c. transition flow d. AOTA 10 Milk is pasteurized if it is heated to 63 oC for 30 min, but if it is heated to 74 oC it only needs 15s for the same result. Find the activation energy of this sterilization process. a. 510,000 J/mol b. 265,000 J/mol c. 610,500 J/mol d. 422,000 J/mol
