ChE Reviewer

NO QUESTION A 1 A valve that controls flow by means of a disk or wedge-shaped gate valve dam sliding at right angles to the direction of flow and seating tightly in the valve body is a 2 The friction factor for flow through a pipe with relative roughness 0.052 of 0.004 at a Reynold's No. of 80,000 is approximately equal to

B butterfly valve

3

The equation that relates friction factor and Reynold's No., smooth pipes f=64/Reynold's No. holds for Oil flows under laminar conditions inside a steam heated copper equal to the pipe. The overall heat transfer coefficient is approximately heat transfer coefficient of the oil

laminar and turbulent flow the average between the heat transfer coefficient of the steam and that of oil

5

In multi-stage liquid-liquid extraction with partially miscible solvents

the minimum number of stages occur when the operating lines are parallel.

6

The enrichment of the vapor steam as it passes through the column in contact with the reflux during distillation is called The maximum number of plates for a given distillation system is variable reflux obtained at The correct unit for the specific rate constant for the reaction A--- square >B determined to be first order is liter/square mol/min On one side of a heat exchanger where either a condensing large effect vapor or a boiling liquid is present, the temperature may be assumed to be constant. In determining the logarithmic mean temperature difference the direction of flow will have For a cylinder where steady-state radial heat transfer takes place the heat flux is constant

stripping

A plate holding a pool of liquid from which rises a vapor whose average composition is in equilibrium with a liquid whose composition is the average of that of the liquid leaving the plate is called Crystallization occurs in a solution that is Mass transfer in a flowing fluid may be correlated by

separation plate

theoretical plate

concentrated Sherwood, Nusselt and Reynold's No settling ratio

unsaturated Peclet, Reynold's and Schimdt No discharge ratio

4

7 8

9

10

11

12 13

14

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

the extraction must be done to form cocurrently in order to minimize the extraction. evaporation

0.025

maximum reflux square liter/square mol/square min little effect

maximum heat transfer rate occurs at the surface

15

16

The rate of formation of C for the reaction 2A + B ---> C is found the rate of the order of to be rate=k(A)(B) formation of C reactio is zero is equal to the rate of disappearance of B A device for increasing the velocity of a fluid in steady flow is a nozzle vent

17

In steady-state backmix flow reactor, composition is

not constant throughout the reactor

constant throughout the reactor

18

The amount of money obtainable from the sale of used property over and above any changers involved in removal and sale is called In fractionation, an increase in reflux ratio

net value

salvage value

increases the number of theoretical plates the ratio of liquid phase resistance to the overall resistance is close to unity

decreases the reboiler duty

Nusselt, Stanton and Reynold's Nos 90-degree long radius elbow switching bank

Nusselt, Prandtl and Reynold's Nos 90-degree standard elbow vent

19

20

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

21

Heat transfer in turbulent flow may be described through an empirical equation correlating

22

Which of the following fittings exhibits the highest pressure drop for the same flow conditions? A chamber into which steam from a high pressure line can be bled during periods of low steam demand from the power plant is called Which one of the following pipes has the highest relative 2" diameter roughness? Wrought iron pipe In steady-state heat transfer through a series of materials with decreases varying resistances, the heat transfer rate towards the direction of heat transfer

23

24

25

26 27 28

Reactions whereby reactants proceed along several paths and give different products are Which one among the following materials has the best insulating property? An operation where warm vapor mixture is cooled such as by contact with a liquid resulting in condensation and decreased humidity is

the gas phase resistance is approximately equal to the total resistance

4" dia Wrought iron pipe varies with the thermal conductivity of each material

polymeric reactions window glass

reversible reactions wood

evaporation

dehumidification

29 30

The pressure exerted on a plane parallel to the direction of flow of a moving fluid is called For mass transfer to take place, there must be a

gauge pressure velocity pressure phase change

reaction component 80 deg F

31

Water vapor condenses at 1 atm on a tube whose surface 212 deg F tmeperature is at 80 deg F. in analyzing the heat transfer through the condensate film, it is best to evaluate the liquid properties at

32 33

The diffusity of water in air at 100 deg F in sq.cm./sec is A fluid flowing at a rate of 25 cubic meters per hour inside a 60 mm I.D. pipe has an average velocity in meter per sec equal to

0.256 5.9

0.278 2.5

34

An equimolar mixture of benzene and toluene is subjected to a single batch distillation. Distillation is discontinued when 60% of the benzene in the feed is distilled. At this instance the bottom product when analyzed shows benzene to be 36.4 mole%. In the distillate, the mole% of benzene is When 32 kg of methane is burned completely the theoretical oxygen required is The standard heat of reaction for the production of water gas, in kcal/gmole, as given by the equation: C(s) + H2O(g) = CO(g) + H2(g) is A rectangular duct 4 ft x 1.5 ft in cross section carries conditioned air. In determining the pressure drop through the duct the equivalent diameter in ft may be used which in this case is

66.6

58.1

16 kg

64 kg

32.2

31.4

4

2.18

A gas decomposition reaction has an activation energy of 245 kJ/mol. The rate of reaction can be accelerated by using a platinum catalyst where the activation energy for the resulting catalyzed reactions is lower at 136 kJ/mol. Using Arrhenius' law and assuming the frequency factor remains the same the catalyzed reaction is faster than the original reaction by a factor of Water at 100 deg F is flowing through a straight 4-in Sch 40 pipe at a rate of 1.0 gal/min. The length of the pipe is 10 ft. The velocity at the center of the pipe in ft per sec is A metallic rod 2 cm in diameter is used as a heating element. The thermal conductivity is 370 J/sec.sq.m.degC. The surface temperature is maintained at 200 deg C. For the center of the rod not to exceed 500 deg C, the maximum volumetric heat generation rate within the metallic rod in J/sec cu.m. must be

over 100,000 over 100 but but less than a less than 200 million

35 36

37

38

39

40

41

42

0.0378

0.0504

4440000

5130000

This is a steady state temperature reached by a small amount of wet-bulb liquid evaporating into a large amount of unsaturated vapor-gas temperature mixture. Air, supplied at the rate of 1200 cfm to a refrigerated coil, has a 74.3 relative humidity of 20% and dry bulb temperature of 150 deg F. The mass flow of dry air entering per minute is

dew point

75

43

In adiabatic humidification, it is possible to maintain the temperature of water constant since

according to the phase rule, the degrees of freedom is 3

the system can be well insulated from the surroundings

44

An air-carbon tetrachloride vapor mixture at 100 deg F dry bulb and 60 deg F wet bulb is heated until the temperature reaches 180 deg F. the final percent relative humidity is about

0.1

0.05

45

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

free moisture

final moisture content

46

This type of drier is used for drying pasty materials such as wet filter cakes and lumpy solids In the constant-rate period, the rate of drying is established by

rotary drier

flash drier

a balance of the heat requirements for evaporation and the rate at which heat reaches the surface desorption

the internal movement of moisture beneath the surface of the solid

47

48 49

50

51 52

53

Unbound moisture in granular and porous solid moves through the intertices of the solid by a mechanism involving Wet solid is to be dried from 40% to 10% in 5 hours under 0.542 hrs constant drying conditions. The critical moisture content is 20% and the equilibrium moisture content is 7%. All moisture contents are on dry basis. The time needed to dry from 15% to 5% free moisture under the same drying conditions is

surface tension

If the rate of drying under constant drying conditions with air at 140 deg F and absolute humidity of 0.03 lb water per lb dry air of unknown mass of solid is given by R=0.5-exp(-60X) [in lb water/hr-sqft], then the equilibrium moisture content (db) of the material is In drying at the falling rate period, the rate at which moisture is removed from the solid material The major problem in diffusion is to promote diffusion of the solute out of the solid and into the liquid. The most effective way of doing this is

0.12

0.034

remains constant to reduce the solid to the smallest size feasible 0.3

increases with time to use counter current operation

A slurry flaked soybeans weighing 100 kg contains 75 kg inert solids and 25 kg of solution 10 weight % oil and 90% wt solvent hexane. This slurry is contacted with 100 kg pure hexane in a single stage so that the value of retention for the outlet underflow is 1.5 kg of insoluble solid per kg solvent in the adhering solution. The composition of underflow leaving the extraction stage in %wt oil is

1.846 hrs

0.8

54

55 56 57

Tung meal containing 55% oil is to be extracted at the rate of 4000 lb per hour using n-hexane containing 5% oil as solvent. A countercurrent mulitple stage extraction system is to be used. The meal retains 2 lb of solvent per pound of oil free meal while the residual charge contain 0.11 lb oil per lb oil free meal while the product is conposed of 15% oil. The theoretical number of ideal stages is The movement of molecules over a substantial distance is associated with the transfer of heat by The mode of heat transfer that can take place in a vacuum is known as The overall conductance for a composite material in series is equal to the

3

4

convection

conduction

convection

conduction

sum of the individual conductances boiling

sum of the individual conductivities condensation

58

Film and drop are terms associated with

59

A 6-in Sch 80 steel pipe is carrying glycerin at an average 99.95 temperature of 100 deg F. The pipe is uninsulated, and the outside temperature is 30 deg F. The inside film conductance is 1000 Btu/h-ft-degF while the outside film conductance is 3.0 Btu/h-sq.ft.-degF. Determine the heat lost [Btu] per minute from a 75-ft length of the pipe. Glycerine is flowing at 800 gpm.

415.7

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=0.45 Btu/h-ft-degF) windows, each 6 in by 8 in by 1/4 in thick. Determine the amount of heat lost [Btu] each day with a surface-to-surface temperature difference of 80 deg F. Determine the length needed for a simple concentric-tube, parallel flow heat exchanger to transfer heat from hot water to cold water at a rate of 900 W. The heat exchanger consists of two Type K copper (k=386 W/m-degC) tubes. The smaller tube has an inside diameter of 49.8 mm and an outside diameter of 54.0 mm. Assume that both film coefficients are equal to 100 W/sq.m.-degC. The hot water enters at 90 degC and leaves at 50 degC, and the cold water enters at 10 degC and leaves at 40 degC. A saturated solution containing 1500 kg of potassium chloride at 360 K is cooled in an open tank to 290K. If the specific gravity of the solution is 1.2, the solubility of potassium chloride per 100 parts of water is 53.55 at 360K and 34.5 at 290K, calculate the amount of crystals obtained assuming that loss of water by evaporation is negligible. An evaporator, working at atmospheric pressure, is to concentrate a solution from 5% to 20% solids at the rate of 1.25 kg/s. The solution which has a specific heat of 4.18 kJ/kg-K is fed to the evpaorator at 295K and boils at 380K. Dry saturated steam at 240 kPa is fed to the calandria and the condensate leaves at the temperature of the condensing steam. If the heat transfer coefficient is 2.3 kW/sq.m-K, what is the required area of heat transfer surface. The latent heat of vaporization maybe taken as the same as that of water.

97

242

185.5 m

11.02 m

4301 kg

1500 kg

55.8 sq.m.

58.5 sq.m.

61

62

63

64

2.5 kg/s of a solution at 288K containing 10% dissolved solids is 115 kPa fed to a forward-feed double effect evaporator operating at a pressure of 14 kPa in the last effect. If the product is to consist of a liquid containing 50% by weight of dissolved solids and dry saturated steam is fed to the steam coils, what should be the pressure of the steam? The surface in each effect is 50 sq.m. and the coefficients for heat transfer in the first and second effects are 2.8 and 1.7 kW/sq.m.-K respectively. Assume that the concentrated solution exhibits a boiling point rise of 5 degK, that the latent heat has a constant value of 2260 kJ/kg and that the specific heat of the liquid stream is constant at 3.75 kJ/kgK.

101.3 kPa

65

An acetone-air mixture containing 0.015 mol fraction of acetone has the mol fraction reduced to 1% of this value by countercurrent absorption with water in a packed tower. The gas flow-rate G is 1 kg/sq.m-s of air and the water entering is 1.6 kg/sq.m-s. For this system, Henry's law holds and Ye=1.75x, where Ye is the mol fraction of acetone in the vapour in equilibrium with a mol fraction x in the liquid. How many overall transfer units are required? 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 total reflux are required to give a product of 80% meta-xylene and 14% para-xylene? The data are given as mole percent. A mixture of alcohol and water with 0.45 mol fraction of alcohol is to be continuously distilled in a column so as to give a top product of 0.825 mol fraction alcohol and a liquor at the bottom with 0.05 mol fraction alcohol. How many theoretical plates are required if the reflux ratio used is 3? Prepared cottonseed meats containing 35% extractable oil are fed to a continuous countercurrent extractor of the intermittent drainage type using hexane as solvent. The extractor consists of ten sections, the section efficiency being 50%. The entrainment, assumed constant, is 1 kg solution/kg solids. What will be the oil concentration in the outflowing solvent if the extractable oil content in the meats is to be reduced to 0.5% by weight?

10.92

9.12

37

38

10

9

72.2

28.7

66

67

68

69

0.4 kg/s of dry seashore sand, containing 1% by weight of salt, is 0.492 to be washed with 0.4 kg/s of fresh water running countercurrent to the sand through two classifiers in series. Assume that perfect mixing of the sand and water occurs in each classifier and that the sand discharged from each classifier contains one part of water for every two of sand (by weight). If the washed sand is dried in a kiln drier, what percent of salt will it retain?

0.429

70

Forty-five pounds per minute of water is heated from 60 to 180 deg F in a 5/8 in., 16 BWG heat exchanger tube. If the steam condensing at 260 deg F, on the outside of the tube gives an hо of 1000 Btu/hr-sq.ft.-degF, calculate the inside heat transfer coefficient [Btu/hr-cu.ft-degF].

696

2173

71

How many cu.ft. per minute of entering air is needed to 12.54 evaporate 10 lb of water per hour from a rayon, if the air enters at 80 deg F and 25% humidity and leaves at 170 deg F and 55% relative humidity. The operating pressure is 14.3 psia.

12.68

72

Nicotine is to be extracted from water using kerosene. If 100 lb of 64.5 a 2% nicotene solution is extracted once with 200 lb of kerosene, what percent of the nicotene is extracted? {Equilibrium data: Y[lb nicotene/lb kerosene] = 0.90X [lb nicotene/lb water]}

54.6

73

We must cool 2500 gpm of water from 120 to 80 deg F. A cooling 77.2 tower, at 70 deg F and 1 atm, is to be 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 the amount lost by evaporation. We wish to build an economical cold room 20 ft square and 10 ft 3537 high. The outside temperature is 80 deg F and te room is to be maintained at 0 deg F. The boss has suggested parallel wooden outer and inner walls separated by a 6-in air space. What will be the heat loss [Btu/hr] through each wall? A colloidal solution is to be concentrated from 15 to 65% solids. 10500 The specific heat of the feed, entering at 50 deg F is 0.93. The pressure of the saturated steam to the evaporator is 10 psia; the condenser pressure is 5-in. Hg abs. The steam chest has an overall heat transfer coefficient of 200 Btu/hr-sq.ft.-degF. Water must be evaporated at the rate of 35,000 lb/hr. Neglecting boiling point elevation, what is the steam consumption [lb/hr]?

150

What is the settling time [sec] for galena particles to settle under free settling conditions through 5 ft of water at 50 deg F. Galena is spherical in shape, with specific gravity and 0.01 inch in diameter. A 10-ft diameter tank with a quick-opening value to a sump has a 10-ft depth of liquid. How long [t in sec] does it take to drain the tank if the valve is assumed to be equivalent to a 4-in diameter orifice? The liquid density is 60 lb/cu.ft. What size sharp-edged orifice [inches] was in use if a flow of 120 gpm produced a 4-in Hg differential in a 4-in Schedule 40 pipe. The fluid, measured at 60 degF, had a viscosity of 1 cSt and a specific gravity of 1. Seven hundred gallons per minute of water are being discharged by a centrifugal pump 5 ft above the pump inlet. The inlet pressure is 4-in Hg above atmospheric and the discharge pressure is 29 psia. If the pump has an 8-inch diameter inlet and a 4-inch diameter discharge, calculate the pump efficiency.

38.1

18.3

2951

1644

2.21

1.35

63

84

74

75

76

77

78

79

8457

35000

80

81

82

83

84

85

86

87

88

Determine the net positive suction head available to a centrifugal 34.2 pump when the level of water is just at the suction point. The pumped fluid is water at 140 deg F and it is pumped from an atmospheric tank at 250 gpm. The tank suction point is 7 ft above 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] Water at 60 deg F flows through a 3-inch Schedule 40 pipe. A 11.61 pitot tube in the pipe shows a 3-inch Hg differential. If the pitot tube is located at the center of the pipe, what is the mass flow rate of the water [lb/s]? The gas phase irreversible reaction A+B---->C is elementary. 113 The entering flow rate of A is 10 mol/min and is equal molar in A and B. The entering concentration of A is 0.4 mol/L. What CSTR volume [L] is necessary to achieve 90% conversion?

27.7

The irreversible zero order gas phase dimerization 2A ----->A2 is carried out in a packed bed reactor with 5 kg of catalyst. The entering pressure is 10 atm and the exit pressure is 1 atm. Pure A enters at a flow rate of 10 mol/min. The reaction is zero order in A. What is the exit conversion? The gas phase reaction 2A+B----->C is carried out in a PFR. The feed is equal molar in A and B and the entering temperature is 500K and the entering pressure is 16.4 atm. If the exit conversion is x, then the exit concentration of B is Heat is generated in a 2.5 cm square copper rod at the rate of 35.3e6 W/cu.m. The rod is exposed to a convection environment at 20 deg C where the convection heat transfer coefficient is 4 kW/sq.m.-degC. Determine the surface temperature [deg C] of the rod. A 5cm diameter cylinder is maintained at a constant temperature of 200 deg C and it is "completely enclosed" by a wind tunnel test chamber, walls of which are at 10 deg C. Air at 350K is forced across the cylinder at a velocity of 50 m/s (h=180 W/m-degC). If the surface emissivity of the cylinder is 0.7, determine the total (i.e., convective and radiative) heat transfer from the cylinder [W per meter length].

0.5

0.15

14.24

227

[B]=0.4(1-x )/(1- [B]=0.4(1-x )/(10.5x ) 1.5x )

75.2

55.2

13

272

A building wall consists of a 6-in of concrete (kc= 0.7 Btu/hr-ft0.028 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 transfer coefficients are 2 and 7 Btu/hr-sqft-degF, respectively. The inside temperature is 72 degF and the outside temperature is 20 degF. Determine the overall heat transfer coefficient for this wall [Btu/hrsqft-degF]. Current is passed through a cylindrical laboratory heater, which 325 has a 3 cm diameter, generating heat at the rate of 20 MW/cu.m. The heater is exposed to a convection environment at 25 degC where the convection heat transfer coefficient is 0.5 kW/sq.m.degC. Determine its surface temperature [degC].

0.119

300

89

A straight rectangular fin has a length of 3.5 cm, a thickness of 1.5 mm, and is made of a material characterized by thermal conductivity of 255 W/m-degC. The fin is exposed to a convection environment at 20 degC and h=1.5 kW/sq.m.-degC. Determine the maximum possible heat transfer from this fin for the base temperature of 150 degC. A gaseous fuel is composed of 20% methane( CH4), 40% ethane (C2H6) and 40% propane (C3H8), where all percentages are by volume. The volumetric analysis of the dry products of combustion (ie. everything except the water) for this fuel gives 10.6% carbon dioxide (CO2), 3% oxygen (O2), 1% carbon monoxide (CO) and 85.4% nitrogen (N2). Determine the air fuel ratio on a mass basis for this reaction. Dodecane (C12H26) gas at 25 degC is burned in a steady flow combustion chamber with 20% excess air that enters at -23.15 degC. The products leave the combustion chamber at 500K. Assuming steady operating conditions and complete combustion, determine the required mass flow rate of the dodecane to supply heat at a rate of 1.5 kW [kg/s]. Two rooms A and B of identical volume are connected by an open doorway. The thermostat in the rooms are set so that Ta B+C is second order, which of the following Ca^2 vs time 1/Ca vs time plots will give a straight line? For the reaction A+B ---> 2C, when Ca is doubled the rate -ra = k Ca^2 -ra = k Ca Cb^2 doubles, when Cb is doubled the rate increases fourfold. The Cb^4 rate law is It states that the rate of a chemical reaction is proportional to the Le Chatelier's Hess' Law activity of the reactants. principle The half life of a material undergoing second order decay is proportional to independent of the square of initial conc the initial conc A fluid flows through 2 CSTR in series. Each reactor has a 66.8 74.7 capacity of 400,000 L and the fluid enters at 100 L per hr. The fluid undergoes a first order decay with a half life of 24 hours. Find the conversion of the fluid. A first order reaction has a specific rate constant of 3e-3 per sec. 0.0021 s 100 s The half life is A certain reaction is 1st order in A. In 30 min, the concentration 45.1 min 19.6 min of A decreases from 0.55 to 0.15 mol/L. The time it will take for A to decrease from 0.35 to 0.15 mol/L is

132 A gas decomposes at 900 degC according to 2A--->2R+S with a 3.83 rate constant of 1000 cc/gmol-s using pure A. The time it will take to react 80% of A in a batch reactor at 900 degC and 1 atm in min is 133 Calculate the length of a chlorinating pipe line with diameter of 25.36 m 0.6 m required to kill 95% of the bacteria in waste water flowing at 0.05 cu.m/s. Test shows that 95.33% kill is obtained in 5 minutes when 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 is used in actual treatment operation.

7.43

134 The set of data given below is for the parallel reaction: a---k1-0.1697 >2R, a---k2-->S. At t=0, Ca=15 moles/cuft, Cr = 1 mole/cuft, Cs=1 mole/cuft; At t=1 hr, Cro = 9 moles/cuft, Cs = 3 moles/cuft. The value of K2 per hour is 135 A batch reaction 2D+E----->F has a conversion factor expressed 257 by the equation r =0.24 t^0.5 where r = conversion factor based on the reactant E; t = time in hours which ranges from 0.5 to 16 hours per batch depending upon the process variables. The average molecular weight of the feed is 60 and a density of 1.4 g/cc. The feed consists of 2 kgmole of D and 1 kgmole of E. The charging, cleaning and discharging time per batch is 2.5 hrs and the volume of the reactor is twice the volume of the feed. Assume 300 days per year and 12 hours operation/day. The volume of the reactor in liters is

0.183

136 A container holds 100 gal of salt solution containing 50 lb of 0.732 dissolved salt. The bottom of the container is covered with a layer of rock salt. The bottom of the container is covered with a layer of 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 brine expressed in lb/gal. If the water in the tank were fresh, the rate of solution would be 1.0 lb/min. Fresh water enters at 3 gpm and brine overflows at the same rate. Assume constant volume at any brine concentration, the concentration of brine in container after 1 hour in lb/gal of salt is

0.427

137 An aqueous solution of ethyl acetate is to be saponified with 10.3 NaOH. The initial concentration of the ethyl acetate is 5 g/L and that of the caustic soda is 0.10M. Values of the second order rate constant in L/gmole-min are k = 23.5 at 0 degC; k = 92.4 at 20 degC. The reaction is essentially irreversible. The time required to saponify 95% of the water at 40 deg C is 138 At 500K the rate of bimolecular reaction is 10 times the rate at 8150 400K. Find E in cal, the activation energy for this reaction from Arrhenius Law. 139 The reaction A+2B--->R is 1st order with respect to each Cao/2m reactant. If equimolar amounts of A and B are introduced into a constant-volume reactor and (1/m) th of A remains after t1, how much will remain after t2=2t1?

11.4

32.5 m

275

9150

Cao/(2m-1)

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

43.1

41.3

141 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 flow rate is changed by approximately a factor of 142 When two centrifugal pumps are connected in series, the discharge changes by a factor of 143 When two reciprocating pumps are connected in parallel, the volumetric capacity of the system changes by a factor of 144 The pressure drop in a pipeline changes by a factor of _____ when the velocity of the flowing fluid is doubled. 145 Cavitation occurs in a centrifugal pump when

1/8

1/16

1/2

1

1/2

1

1/2

1

the discharge pressure becomes too high 0.63

the discharge valve is closed

146 Oil with a viscosity of 30 cP and a density of 60 lb/cu.ft. flows through a 1/2-inch inside diameter pipe. Determine the velocity in fps below which flow will be laminar. 147 Water at 60 deg F flows through a 3-inch inside diameter smooth 1.05 horizontal pipe. If the Reynold's number is 353000, calculate the ratio of maximum velocity to average velocity. 148 The pressure after the pump in a 6-inch inside diameter smooth 0.6 pipe conducting water is 20 psia. The water is discharged at an open tank 100 ft from the pump. Calculate the rate of discharge of water in cu.ft/s. 149 A water storage tank assumes the supply of water into a factory. PhP 3300 Water is supplied to the tank through a booster pump installed in the water line. The theoretical pump horsepower required is 3.25 hp. What is the monthly 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 hr a day.

13.1

150 When the impeller speed of an ideal centrifugal pump is doubled, 1/2 the vol. flow rate of discharge is increased by a factor of

1

151 The differential height between two points which a fluid has to be transferred is the 152 The resistance of a layer of fluid to flow over the next layer is measured by 153 An axial flow pump operating at a speed of 880 rpm can supply water at a rate of 3000 gpm. The maximum head that this pump can deliver in ft. of water is 154 Specify the type of open impeller pump to use if the capacity is 400 gpm at a head of 200 ft of water.

potential head

pressure head

viscosity

friction factor

20

36

3x2x8.5E

4x3x8.5E

1.22

3.58

PhP 5000

155 What will be the rated capacity [gpm] of a 4-1/2 inch impeller centrifugal pump operating at a speed of 3450 rpm capable of generating a head of 40 ft of water. 156 If the speed of a centrifugal pump is doubled, the energy requirement becomes approximately ___ times the original energy requirement. 157 A cylindrical tank 1 ft in diameter discharges through a nozzle connected to the base. Find the time needed for the water level in the tank to drop from 4 ft to 2 ft above the nozzle. The diameter of the nozzle is 1 inch and its discharge coefficient maybe taken as unity. 158 The NPSH of a single suction centrifugal hot water pump at a speed of 3550 rpm operating at a pressure of 600 psi and a capacity of 450 gpm is ___ ft. 159 The rate of evaporation at a given operating temperature in a n evaporator is more when

95

134

2

4

32

55

15

20

when the the operating operating pressure is low pressure is high

160 An optimim number of the effects for a given application is a capacity function of the 161 A popular type of heat exchanger for cooling large quantities of double-pipe fluid is the 162 An evaporator is used to concentrate 10,000 lb/hr of a 20% 0.82 o solution of NaOH in water at 140 F using saturated steam at 25 psia at a rate of 7,000 lb/hr. The OHTC is 275 BTU/hr-ft2-oF when the pressure in the vapor is 1.7 psia. The steam economy, SE, is 163 A cross flow heat exchanger uses mixed air at 4 kg/s that enters 22.2 m2 at 15oC and leaves at 45oC. The air cools unmixed water, which enters at 95oC and 0.70 kg/s. The OHTC equals 150 W/m 2-oC. After several months of operation, a scale resistance of 0.002 m 2o C/W developed. 16. The heat transfer area required to accomplish the change is 164 As solution of 28% wt Na2SO4 is to be crystallized to yield 285.3 Glauber salt in a four section (one section is 10 ft in length) Swenson Walker Crystallizer. It is fed to the unit at 120oF and cooled to 60oF using cooling water which enters at 50oF and leaves at 70oF. The crystallizer has a cooling surface of 3 ft2 per foot of length. The feed rate is 500 lb/hr and the crystallizer is seeded with 50 lb/hr of 65 mesh crystals. 19. The amount of the crystalline crop (C) produced in lb per hour is

economy

165 An insulator should have

low thermal conductivity

high thermal conductivity

166 Fouling factor

is a dimensionless quantity

does not provide a safety factor for design

plate 0.863

25 m2

249.3

167 Natural convection is characterized by 168 The Graetz number is concerned with

169 Dropwise condensation occurs on

170 Dietus-Boelter equation for determination of heat transfer coefficient is valid

Reynolds number mass transfer between a gas and a liquid clean and dirt free surfaces

Grashhoff number absorption with chemical reaction smooth clean surfaces

for liquid metals for fluid in laminar flow

171 A type of pneumatic conveyor system characterized by a material fluidizing moving in an air stream or pressure less than ambient.

pressure

172 If the total percentage of particles larger than the screen opening 0.98 in the feed, oversize, undersize are 36%, 89% and 3%, respectively, the effectiveness of the screen if the undersize is the product is 173 The estimated width of an apron conveyor having a capacity of 305 mm 75 tons/hr at a speed of 50 ft/min is 174 It is defined as the ratio of the average diameter of the feed to settling ratio the average diameter of the product.

0.89

175 The sphericity of cubical particles is 1 176 The separation of a dilute slurry or suspension by gravity settling thickening into a clear fluid and a slurry or suspension by gravity settling into a clear fluid and a slurry of higher solids content is called

0.87 classification

610 mm screen-mesh no

177 An ultracentrifuge is used to separate high-molecular weight temperature pressure fractions in polymeric or biological systems. What is the gradient for mass transfer in the separation using this mass transfer device? 178 Ordinary diffusion takes place because of ___ driving force. temperature pressure 179 What are the two limiting cases of steady-state diffusion? UMD and EMD ordinary and Knudsen 180 Which of the following is not true in (binary) equimolar counterDAB = DBA c = cA + cB diffusion? 181 A fluid is flowing on a surface, which contains a component that leaches out to the fluid. Assuming that all the 3 regions of mass transfer are present, in which of these regions is diffusion controlling? 182 In unsteady-state mass transfer, the quantity (DABt/rm^2) is referred to as 183 What is the equivalent of Prandtl number in convective mass transfer? 184 If kx > ky, then the controlling phase is

Knudsen region turbulent region

185 In two-phase mass transfer, equilibrium may exist

at the interface in the gas phase

unaccomplishe relative d change resistance Sc

Sh

the liquid phase the gas phase

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

cooling of air

air conditioning

187 Air conditioning in tropical countries involves

humidification by a process similar to that in a cooling tower

188 What do you call the steady-state non-equilibrium temperature reached when a small amount of water is contacted under adiabatic conditions by a continuous stream of gas?

dry-bulb temperature

humidification by a process similar to airwater vapor saturator wet-bulb temperature

189 The moisture content of a solid is given as 50% wet basis. What 0.5 1 is the moisture content, dry basis? 190 The moisture that can be removed by drying is called equilibrium bound moisture moisture 191 Falling-period in drying terminates at the end of constant- origin of R vs X rate period plot 192 Which is not true at the interphase of a gas scrubbing operation? the solute concentration of the gas is less than that of the bulk 193 He and N2 gas are contained in a conduit 5 mm in diameter and 2.35 exp -5 a 0.1 m long at 298 K and a uniform pressure of He at one end of the tube is 0.6 atm and 0.02 atm at the other end. Assuming equimolar countercurrent diffusion, the flux in kmol/s-m 2 is

the solute concentration of the liquid is less than that of the bulk 2.44exp -5

194 100 m3/hr of air at 60C and 20% RH is needed for a chemical reactor. This will be obtained from process air at 60C and 10% RH by humidifying adiabatically the process air followed by heating to its original temperature. The wattage of the heater at 80% efficiency is 195 Wet solid is to be dried from 36% to 8% moisture in 5 hr under constant drying condition. Critical and equilibrium moisture contents are 14 and 4% respectively. Calculate how much longer will it take to dry the same material from 8% to 5.5% moisture under constant drying condition. All moisture contents are on a dry basis. 196 The unit of volumetric diffusivity is 197 If reflux to a distillation column is 100 moles/hr, when the overhead product rate is 50 moles/hr. the reflux ratio is 198 Which of the following provides maximum contact surface for a liquid-vapour system? 199 In extraction, as the temperature increases, the area of heterogeneity (area covered by bimodal curve) 200 The suitable evaporator for concentration of foaming liquids is

5280

8490

1 hr

1.6 hr

cm^2/sec 0.5

cm/sec 2

packed lower decreases

bubble-cup plate column increases

long tube evaporator molecular diffusion

short tube evaporator unsteady-state diffusion

201 Macroscopic transfer of mass between moving fluid and surface which is of different concentration is called

202 For a packed column the main purpose of packing is to

strengthen the column

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

the NTU is zero the liquid flow rate is maximum

204 Methanol diffuses in 0.15 cm stagnant film of 1:1 mole mixture of 0.15 hydrogen and CO2 at 100oC and 2 atm. The partial pressures of methanol on both sides are 0.6 and 0.2 atm. The average diffusivity of methanol in the hydrogen and CO2 at 0 oC and 1 atm in cm2/s is 205 Gaseous reactant A decomposes according to the reaction A --> 0.92 3R (-rA = 0.5 CA mole/L-min). The feed, which consists of 70% A

increase the surface area

0.31

0.86

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? 206 Between 0 degC and 50 degC, the average activation energy of a 14.7 certain reaction is 80 kJ/mol. How many times faster will the reaction occur at 300 K than at 275 K? 207 Consider a gas-phase reaction 2A ---> R + 2S with unknown 0.54 min kinetics. A space velocity of 0.8/min is needed for 95% conversion of A in a PFR. Find the mean residence time or holding time of the fluid in the PFR. 208 For Newtonian fluids, the shear stress is constant.

18.5

0.85 min

209 An ideal fluid is one that is

compressible

210 Water flows through an 8-in (ID=7.981 in) steel pipe at an average velocity of 6 ft/s. Downstream the pipe splits into an 8-in main and a 2 in (ID=2.067 in) bypass pipes. If the velocity in the bypass is twice the velocity of the main pipe, the volumetric flow rate [ft3/s] in the main pipe is 211 An imaginary line within a fluid flow such that a tangent at any point indicates the direction of flow at that point. 212 Air at 250C [viscosity=0.018 cP] enters a section of 2-in schedule 40 commercial steel pipe at a gauge pressure of 310 kPa and a flow rate of 1200 kg/h. Assuming isothermal flow, what is the pressure drop [kPa] in 60 m of pipe? 213 A simple pitot tube measures

10.58

inversely proportional to rate of deformation. incompressible & viscous 5.29

stream tube

velocity profile

350

155

acoustical velocity pitot tube

superficial velocity orifice

214 Which of the following meters will have the highest permanent pressure loss? 215 In the flow meter equation, Y, indicates the 216 The loss due to sudden contraction is proportional to 217 Stoke’s law is valid when the particle Reynolds number is 218 Priming needed in a

mass flow rate compressibility factor velocity turbulence 1 Reciprocating Gear pump pump

219 Maximum theoretical suction lift for water at 60˚F by a centrifugal 40 ft pump is 34 ft. The same for water at 200˚F will be 220 The most economical valve for use with large diameter pipes. butterfly 221 Multistage compressors are used in industry because, they reduce the cost of compressor

222 For ideally incompressible fluid, the mach number will be 223 of the following produces maximum pressure difference for transportation of gases? 224 The fluid property which matters for falling rain drops to acquire spherical shape is its 225 A wastewater solution having a volume of 1000 L contains 0.21 kg phenol/m3 of solution. A total of 1.40 kg fresh granular activated carbon is added to the solution, which is then mixed thoroughly to reach equilibrium. What is the amount of phenol absorbed per kg carbon at equilibrium? 226 The overhead product composition decreases with time in

227 228

229

230

231

232 233

37 ft globe reduce the size requirement

0 1 vacuum pumps blowers pressure 0.007 kg

height of descend 0.106 kg

batch distillation continuous with reflux distillation with reflux For a binary mixture with low relativity, continuous rectification to low reflux ratio small crossget pure products will require section Chemisorption is the same as characterized by van der Waals adsorption of heat The stage efficiency in leaching depends on the time of contact rate of diffusion between the of the solute solid and the through the solid solution and into the liquid Weeping in distillation or absorption column increases tray provides larger efficiency surface for mass transfer What are the two contacting phase in leaching? extract phase solvent phase and raffinate and solute phase phase Hydrogen sulfide is removed from water by contacting the Distillation Leaching solution with warm air. The operation is Disregarding the cost, which is the best solvent for the extraction caproic acid chloroform of acetic acid from an aqueous solution at 25deg C?

234 Professional Regulations Commission was created under 235 A chemical engineer who designed and built a new type pf reactor and for three years, sold many units to the public can still patent his reactor. 236 A person who has passed the Chemical Licensure Examination can take his/her oath as a chemical engineer if his/her age is not less than _______ years. 237 Which of the following is not a requirement for utility model registration?

P.D. No. 223 TRUE

P.D. No. 233 FALSE

18

19

inventive step

novelty

238 A section of the patent application containing detailed descriptions of the benefits obtained from using the invention is called the 239 A document issued by the DENR secretary indicating that the proposed project will cause significant negative environmental impact. 240 In the Philippines, sulfur for sulfuric acid manufacturing is sourced from _______ industry. 241 Sulfur is undesirable in petroleum because

disclosure

abstract

Environmental Impact Statement paper

Environmental Compliance Certificate cement

it causes engine knocking

it increases the boiling pt of fuel

242 Materials added to detergent formulation to enhance cleaning performance by exhibiting synergistic cleaning effect with surfactant. 243 Polyethylene is an example of _____________ polymerization

fillers

brighteners

condensation

addition

244 Principal chemical conversion in the production of resin from monomer. 245 Carbon black is added to rubber compounding as 246 The binder for all the powder materials of paint 247 A fibrous material left after cane sugar has been milled is commonly called as 248 Molasses is a by product of raw sugar from the ______ process

condensation

hydration

activator pigment bagasse

curing agent vehicle pulp

milling

extraction

249 Kraft process is a common name for 250 Water insoluble cell binders of wood 251 DDT means

sulfate pulping pulp Diphenyldichlor otriphenylethan e decoloration pigment

sulfite pulping cellulose dichlorodiphenyl dichloroethane

254 Plasticisers are added to paints to

make it corrosion resistant

make glossy surface

255 Silicone is

thermoplastic

a monomer

256 The process involved in converting rubber into a thin sheet or coating it on fabric is called 257 Alkyl benzene sulfonate (ABS) is a 258 Neoprene is a

extrusion

mastication

detergent monomer

rubber synthetic rubber

259 Steam enters an adiabatic turbine at 10 MPa and 500 degC 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. 260 Work is a

0.2348

0.3216

property of the system

path function

252 Rancidity of oil can be reduced by 253 Varnish does not contain

hydrogenation dryer

261 Throttling process is

a reversible an irreversible and isothermal and constant process entropy

262 A sample consisting of 1.00 mole of Argon gas is expanded isothermally and reversibly at 0C from 22.4L to 44.8L. The heat absorbed by the system is 263 Maximum work can be obtained from a system when the change taking place in it is 264 The ratio of work performed by a system and the heat it absorbed from a reservoir is referred to 265 According to the first law of thermodynamics

0

+1.13 kJ

isothermal

adiabatic

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

greater than 0.85

267 In choosing the refrigerant, the fluid must have the following characteristics, except

environmentally has a vapor benign pressure less than atmospheric

268 Coolers and boilers are ordinarily operated at ________ condition. 269 For an isolated system, maximum entropy will occur at

isobaric

isenthalpic

half-life

critical condition

270 A carnot cycle consists of

two isothermal and two adiabatic process

two isochoric and two adiabatic process

271 This is also known as the volume fraction of the voids in packed beds. 272 A measure of the ratio of the drag force acting on a unit area of the impeller & the inertial stress. 273 Sulfuric acid is pumped at 3 kg/s through a 60-m length of smooth 25 mm pipe. If the pressure drop falls by one-half, what will be the new flow rate [kg/s]? Assume the following properties of sulfuric acid: SG = 1.84, viscosity = 25 cP.

sphericity

porosity

Gibb’s free energy Energy is Perpetual neither lost nor motion is gained in any possible. energy transformation. Entropy

in between 0.75 and 0.85

Froude number Reynold’s number 3 2

274 The equation del(P) = -(rho)(g) del(z) is known as the hydrostatic shear forces fluid is are not involved incompressible vertical law for which all the following assumptions are applied, except

275 Which of the following can be adjusted by human operator in a closed feedback control loop? 276 The thermocouple is based on the Seebeck effect which states that a/an _____ is generated when opposite junction of certain dissimilar pairs of wires are exposed to different temperatures.

set point

controller output

current

temperature

277 Dead time is a function of distance and momentum 278 A pneumatic controller is used to control temperature within the 2.83kPa/K range 280K to 310K. The controller is adjusted so that the output pressure goes from 20kPa (valve fully open) to 105 Kpa (valve fully closed) as the measured temperature goes from 295K to 300K with the sent point held constant. What is the proportional gain? 279 The parameter which completely describes the behavior of the Time constant response to a disturbance of a second order system is the

acceleration 0.35kPa/K

280 Water is flowing through a 3-inch schedule 40 pipe at 60 deg F. 11.61 ft/s A pitot tube is inserted at the centerline of the pipe and registers a 3-inch Hg differential. What is the mass flow rate of the water?

37.1 kg/s

281 An oil well is 1200 ft below ground level. Oil at 500 psig at the bottom flows to ground level through a 12-inch schedule 80 commercial steel pipe. The oil has a SG of 0.86 and viscosity of 8 cP. The vol flow rate of oil in barrels per hour is 282 The equivalent diameter of a concentric annular space where 1inch OD pipe is located inside a 2-inch ID pipe is 283 Based on Bond's crushing law, the power required to crush a certain material will change by _____% if the diameter of the product is made smaller by 50%. 284 The BPR of a 50% NaOH solution at an evaporator pressure of 4.7 psia is

9365

9461

pi/4 inch

1 inch

20.2

41.4

73 degF

173 degF

damping coefficient

C globe valve

0.03

D

ANSWER

SCORE

a

1

orifice

0.038 0

turbulent flow only equal to the heat transfer coefficient equivalent to the resistance offerred by the pipe the minimum number of stages occur when the tie line coincides with an operating line. rectification

laminar flow only equal to the heat transfer coefficient of the steam

the amount of solvent used must be enough to form 2 phases.

fractionation

minimum reflux optimum reflux mol/liter/min

0

d

1

b

1

c

1

c

1

liter/mol/min 0

no effect

the heat transfer is constant

transition plate

significant effect

0

the temperature is uniform throughout the cylinder bubble plate

0

0 supersaturated Sherwood, Reynold's and Schimdt No reduction ratio

saturated Prandtl, Schimdt and Reynold's No classification ratio

c

1 0

c

1

the value of k is the reaction independent of cannot proceed the initial concentrations of A and B orifice

venturi

a function of time

not uniform throughout the reactor and varies from time to time market value

book value

0

a

0

b increases the amount of distillate

1

increases the condenser duty

1

0

the gas phase resistance is negligible

the ratio of gas phase resistance to liquid resistance is approximately zero Peclet, Stanton Schimdt, and Prandtl Nos Peclet and Friction Nos 45-degree square-corner standard elbow elbow compressor accumulator

0

0 0 b

1" dia Drawn tubing

4" dia Riveted steel pipe

through each material is inversely proportional to the thickness of the material parallel reactions air

is constant throughout the series of materials

humidification

extraction

consecutive reactions concret

1

0

0

c

1

b

1

b

1

tangential pressure concentration gradient 113 deg F

1.484 1.5

static pressure momentum gradient 146 deg F

0.581 0.6

b

1

c

1

c

1

b

1 0

33.4

54.4 0

128 kg

32 kg

26.4

57.8

c

1 0

1.5

2.75 0

over 20 million

over 2 but less than 3 0

0.0454

0.0252 0

6930000

2040000 0

saturation temperature

dry-bulb temperature

75.26

78.5

0

0

the temperature of the air can also be maintained constant

increase in the humidity of the air is insignificant

0.02

0.01

0

0 equilibrium moisture content tray drier

critical moisture content freeze drier

c

1

c

1

air flow air flow parallel perpendicular to to the solid the surface of surface the solid

surface renewal moisture diffusivity 2.129 hrs 3.42 hrs

0

d

1

0

0.01155

0.00116 0

decreases with time to use cross flow evaporation

no drying takes place to use spray percolators

1.5

2.3

0

0

0

5

6

0

radiation

all of A, B and C radiation all of A, B and C inverse of the sum of the total resistance individual resistances evaporation all of A, B and C 451.7 475.1

a

1

c

1

c

1

b

1

0

5800

139200 0

5.51 m

4.14 m

0

966 kg

534 kg 0

85.8 sq.m.

88.5 sq.m.

0

14 kPa

zero gauge

0

4.72

3.03

0

39

40 0

8

7 0

27.8

22.7

0

0.294

0.249

0

577

241 0

13.76

16.28 0

46.5

45.6 0

227.2

300 0

11994

20451 0

40130

45500

0

13.8

5 0

1163

19.4 0

4.67

2 0

95

100 0

7

0.52

0

31.7

37.1 0

851

900 0

0.75

1 0

[B]=0.4(10.5x )/(1-x )

[B]=0.2

25.2

20

0

0

3478

3750

0

0.714

6.01

0

100

25 0

13943 W

19343 W 0

23

33

0

38

0.038 0

both contain the same no of air molecules increases by decreases. about 40% stays constant. stays the same. may increase or decrease. The application The application should be should be rejected given full because it consideration violates both because it 1st and 2nd does not laws of Thermo. violate any laws of Thermodynami cs. increases 8x.

0 c

1

c

1

a

1

0

increases 16x. 0

3 e7

5.2 e8

0

excess reactant product yield reactant ratio

Latent Heat of Condensation moisture

Ultimate analysis O2-free basis Dulong's formula 32.48 2.38

fresh-feed conversion Net Calorific Value volatile combustible matters Elemental analysis N2-free basis Oxygen unaccounted for equation 42.56 6.13

b

1

b

1 0 0 0 0 0 0 0

absolute 60% saturation humidity of 0.05 PhP 434.16

0

PhP 450 0

0.03

0.05 0

4350

6000 0

9.5

17 0

0.9

0.92 0

51.2

22.76 0

7.86

23.1 0

1/conc 2

1/conc-time 1.5

adding a catalyst

removing the products of the reaction the net equation the rate law.

0 0 0

0 does not depend on the initial concentrations 8

is not a characteristic of the reaction

nature of reactants >0 log Ca vs reciprocal time lof Ca vs time

temperature

-ra = k Ca

-ra = k Cb^2

16

2R+S with a rate 3.83 constant of 1000 cc/gmol-s using pure A. The time it will take to react 80% of A in a batch reactor at 900 degC and 1 atm in min is

molecularity of the reaction 2 Ca vs time

Calculate the length of a chlorinating pipe line with diameter of 0.6 m 25.36 m required to kill 95% of the bacteria in waste water flowing at 0.05 cu.m/s. Test shows that 95.33% kill is obtained in 5 minutes when 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 is used in actual treatment operation. The set of data given below is for the parallel reaction: a---k1-->2R, a--- 0.1697 k2-->S. At t=0, Ca=15 moles/cuft, Cr = 1 mole/cuft, Cs=1 mole/cuft; At t=1 hr, Cro = 9 moles/cuft, Cs = 3 moles/cuft. The value of K2 per hour is

32.5 m

1/Ca vs time -ra = k Ca Cb^2 Hess' Law independent of initial conc 74.7

100 s 19.6 min

7.43

0.183

A batch reaction 2D+E----->F has a conversion factor expressed by the 257 equation r =0.24 t^0.5 where r = conversion factor based on the reactant E; t = time in hours which ranges from 0.5 to 16 hours per batch depending upon the process variables. The average molecular weight of the feed is 60 and a density of 1.4 g/cc. The feed consists of 2 kgmole of D and 1 kgmole of E. The charging, cleaning and discharging time per batch is 2.5 hrs and the volume of the reactor is twice the volume of the feed. Assume 300 days per year and 12 hours operation/day. The volume of the reactor in liters is

275

A container holds 100 gal of salt solution containing 50 lb of dissolved salt. The bottom of the container is covered with a layer of rock salt. The bottom of the container is covered with a layer of 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 brine expressed in lb/gal. If the water in the tank were fresh, the rate of solution would be 1.0 lb/min. Fresh water enters at 3 gpm and brine overflows at the same rate. Assume constant volume at any brine concentration, the concentration of brine in container after 1 hour in lb/gal of salt is

0.427

0.732

An aqueous solution of ethyl acetate is to be saponified with NaOH. The 10.3 initial concentration of the ethyl acetate is 5 g/L and that of the caustic soda is 0.10M. Values of the second order rate constant in L/gmole-min are k = 23.5 at 0 degC; k = 92.4 at 20 degC. The reaction is essentially irreversible. The time required to saponify 95% of the water at 40 deg C is At 500K the rate of bimolecular reaction is 10 times the rate at 400K. 8150 Find E in cal, the activation energy for this reaction from Arrhenius Law.

11.4

The reaction A+2B--->R is 1st order with respect to each reactant. If equimolar amounts of A and B are introduced into a constant-volume reactor and (1/m) th of A remains after t1, how much will remain after t2=2t1? When the 1st order homogeneous reaction (gas-phase) A--->2.5R is carried out in an isothermal batch reactor at 2 atm with 20% inerts present, the volume increases by 60% in 20 min. When the reaction is carried out in a constant volume reactor, the time required for the pressure to reach 8 atm if the initial pressure is 5 atm, 2 atm of which consist of inerts in min is 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 flow rate is changed by approximately a factor of

Cao/2m

Cao/(2m-1)

43.1

41.3

1/8

1/16

When two centrifugal pumps are connected in series, the discharge changes by a factor of When two reciprocating pumps are connected in parallel, the volumetric capacity of the system changes by a factor of The pressure drop in a pipeline changes by a factor of _____ when the velocity of the flowing fluid is doubled.

1/2

1

1/2

1

1/2

1

9150

Cavitation occurs in a centrifugal pump when

the discharge pressure becomes too high Oil with a viscosity of 30 cP and a density of 60 lb/cu.ft. flows through a 0.63 1/2-inch inside diameter pipe. Determine the velocity in fps below which flow will be laminar. Water at 60 deg F flows through a 3-inch inside diameter smooth 1.05 horizontal pipe. If the Reynold's number is 353000, calculate the ratio of maximum velocity to average velocity. The pressure after the pump in a 6-inch inside diameter smooth pipe 0.6 conducting water is 20 psia. The water is discharged at an open tank 100 ft from the pump. Calculate the rate of discharge of water in cu.ft/s.

the discharge valve is closed

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 is 3.25 hp. What is the monthly 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 hr a day. When the impeller speed of an ideal centrifugal pump is doubled, the vol. flow rate of discharge is increased by a factor of The differential height between two points which a fluid has to be transferred is the The resistance of a layer of fluid to flow over the next layer is measured by An axial flow pump operating at a speed of 880 rpm can supply water at a rate of 3000 gpm. The maximum head that this pump can deliver in ft. of water is Specify the type of open impeller pump to use if the capacity is 400 gpm at a head of 200 ft of water. What will be the rated capacity [gpm] of a 4-1/2 inch impeller centrifugal pump operating at a speed of 3450 rpm capable of generating a head of 40 ft of water. If the speed of a centrifugal pump is doubled, the energy requirement becomes approximately ___ times the original energy requirement.

PhP 3300

PhP 5000

1/2

1

potential head

pressure head

viscosity

friction factor

20

36

3x2x8.5E

4x3x8.5E

95

134

2

4

A cylindrical tank 1 ft in diameter discharges through a nozzle connected to the base. Find the time needed for the water level in the tank to drop from 4 ft to 2 ft above the nozzle. The diameter of the nozzle is 1 inch and its discharge coefficient maybe taken as unity.

32

55

The NPSH of a single suction centrifugal hot water pump at a speed of 3550 rpm operating at a pressure of 600 psi and a capacity of 450 gpm is ___ ft. The rate of evaporation at a given operating temperature in a n evaporator is more when

15

20

13.1

1.22

3.58

when the operating the operating pressure is high pressure is low

An optimim number of the effects for a given application is a function of capacity the A popular type of heat exchanger for cooling large quantities of fluid is double-pipe the

economy plate

An evaporator is used to concentrate 10,000 lb/hr of a 20% solution of 0.82 NaOH in water at 140oF using saturated steam at 25 psia at a rate of 7,000 lb/hr. The OHTC is 275 BTU/hr-ft2-oF when the pressure in the vapor is 1.7 psia. The steam economy, SE, is A cross flow heat exchanger uses mixed air at 4 kg/s that enters at 15oC 22.2 m2 and leaves at 45oC. The air cools unmixed water, which enters at 95oC and 0.70 kg/s. The OHTC equals 150 W/m2-oC. After several months of operation, a scale resistance of 0.002 m2-oC/W developed. 16. The heat transfer area required to accomplish the change is

0.863

As solution of 28% wt Na2SO4 is to be crystallized to yield Glauber salt in 285.3 a four section (one section is 10 ft in length) Swenson Walker Crystallizer. It is fed to the unit at 120oF and cooled to 60oF using cooling water which enters at 50oF and leaves at 70oF. The crystallizer has a cooling surface of 3 ft2 per foot of length. The feed rate is 500 lb/hr and the crystallizer is seeded with 50 lb/hr of 65 mesh crystals. 19. The amount of the crystalline crop (C) produced in lb per hour is

249.3

An insulator should have

low thermal conductivity is a dimensionless quantity

high thermal conductivity does not provide a safety factor for design

Reynolds number mass transfer between a gas and a liquid clean and dirt free surfaces for liquid metals

Grashhoff number absorption with chemical reaction

Fouling factor

Natural convection is characterized by The Graetz number is concerned with

Dropwise condensation occurs on Dietus-Boelter equation for determination of heat transfer co-efficient is valid

25 m2

smooth clean surfaces for fluid in laminar flow

A type of pneumatic conveyor system characterized by a material fluidizing moving in an air stream or pressure less than ambient. If the total percentage of particles larger than the screen opening in the 0.98 feed, oversize, undersize are 36%, 89% and 3%, respectively, the effectiveness of the screen if the undersize is the product is

pressure

The estimated width of an apron conveyor having a capacity of 75 tons/hr at a speed of 50 ft/min is It is defined as the ratio of the average diameter of the feed to the average diameter of the product. The sphericity of cubical particles is The separation of a dilute slurry or suspension by gravity settling into a clear fluid and a slurry or suspension by gravity settling into a clear fluid and a slurry of higher solids content is called

305 mm

610 mm

settling ratio

screen-mesh no

1 thickening

0.87 classification

0.89

An ultracentrifuge is used to separate high-molecular weight fractions in polymeric or biological systems. What is the gradient for mass transfer in the separation using this mass transfer device?

temperature

pressure

Ordinary diffusion takes place because of ___ driving force. What are the two limiting cases of steady-state diffusion?

temperature UMD and EMD

pressure ordinary and Knudsen c = cA + cB

Which of the following is not true in (binary) equimolar counterDAB = DBA diffusion? A fluid is flowing on a surface, which contains a component that leaches Knudsen region out to the fluid. Assuming that all the 3 regions of mass transfer are present, in which of these regions is diffusion controlling?

turbulent region

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

relative resistance

What is the equivalent of Prandtl number in convective mass transfer?

Sc

Sh

If kx > ky, then the controlling phase is

the liquid phase

the gas phase

In two-phase mass transfer, equilibrium may exist

at the interface

in the gas phase

Which of the following processes may always be regarded as a constant- cooling of air humidity process? Air conditioning in tropical countries involves humidification by a process similar to that in a cooling tower What do you call the steady-state non-equilibrium temperature dry-bulb reached when a small amount of water is contacted under adiabatic temperature conditions by a continuous stream of gas? The moisture content of a solid is given as 50% wet basis. What is the 0.5 moisture content, dry basis? The moisture that can be removed by drying is called equilibrium moisture Falling-period in drying terminates at the end of constantrate period Which is not true at the interphase of a gas scrubbing operation? the solute concentration of the gas is less than that of the bulk

air conditioning

He and N2 gas are contained in a conduit 5 mm in diameter and a 0.1 m 2.35 exp -5 long at 298 K and a uniform pressure of He at one end of the tube is 0.6 atm and 0.02 atm at the other end. Assuming equimolar countercurrent diffusion, the flux in kmol/s-m2 is 100 m3/hr of air at 60°C and 20% RH is needed for a chemical reactor. 5280 This will be obtained from process air at 60°C and 10% RH by humidifying adiabatically the process air followed by heating to its original temperature. The wattage of the heater at 80% efficiency is

2.44exp -5

humidification by a process similar to air-water vapor saturator wet-bulb temperature 1 bound moisture origin of R vs X plot the solute concentration of the liquid is less than that of the bulk

8490

Wet solid is to be dried from 36% to 8% moisture in 5 hr under constant 1 hr drying condition. Critical and equilibrium moisture contents are 14 and 4% respectively. Calculate how much longer will it take to dry the same material from 8% to 5.5% moisture under constant drying condition. All moisture contents are on a dry basis. The unit of volumetric diffusivity is

cm^2/sec 0.5

1.6 hr

cm/sec

If reflux to a distillation column is 100 moles/hr, when the overhead product rate is 50 moles/hr. the reflux ratio is Which of the following provides maximum contact surface for a liquid- packed lower vapour system? In extraction, as the temperature increases, the area of heterogeneity decreases (area covered by bimodal curve) The suitable evaporator for concentration of foaming liquids is long tube evaporator Macroscopic transfer of mass between moving fluid and surface which molecular diffusion is of different concentration is called For a packed column the main purpose of packing is to strengthen the column

2

In a gas absorption operation, when the operating line crosses the equilibrium curve Methanol diffuses in 0.15 cm stagnant film of 1:1 mole mixture of hydrogen and CO2 at 100oC and 2 atm. The partial pressures of methanol on both sides are 0.6 and 0.2 atm. The average diffusivity of methanol in the hydrogen and CO2 at 0 oC and 1 atm in cm2/s is

the liquid flow rate is maximum 0.31

the NTU is zero 0.15

Gaseous reactant A decomposes according to the reaction A --> 3R (-rA = 0.92 0.5 CA mole/L-min). The feed, 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? Between 0 degC and 50 degC, the average activation energy of a certain 14.7 reaction is 80 kJ/mol. How many times faster will the reaction occur at 300 K than at 275 K? Consider a gas-phase reaction 2A ---> R + 2S with unknown kinetics. A 0.54 min space velocity of 0.8/min is needed for 95% conversion of A in a PFR. Find the mean residence time or holding time of the fluid in the PFR.

bubble-cup plate column increases short tube evaporator unsteady-state diffusion increase the surface area

0.86

18.5

0.85 min

For Newtonian fluids, the shear stress is

constant.

inversely proportional to rate of deformation.

An ideal fluid is one that is

compressible

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

10.58

incompressible & viscous 5.29

An imaginary line within a fluid flow such that a tangent at any point stream tube indicates the direction of flow at that point. 350 Air at 250C [viscosity=0.018 cP] enters a section of 2-in schedule 40 commercial steel pipe at a gauge pressure of 310 kPa and a flow rate of 1200 kg/h. Assuming isothermal flow, what is the pressure drop [kPa] in 60 m of pipe? A simple pitot tube measures acoustical velocity

velocity profile

Which of the following meters will have the highest permanent pressure loss? In the flow meter equation, Y, indicates the

pitot tube

orifice

mass flow rate

The loss due to sudden contraction is proportional to Stoke’s law is valid when the particle Reynolds number is Priming needed in a

velocity 1 Gear pump

Maximum theoretical suction lift for water at 60˚F by a centrifugal pump is 34 ft. The same for water at 200˚F will be The most economical valve for use with large diameter pipes. Multistage compressors are used in industry because, they

155

superficial velocity

37 ft

butterfly reduce the cost of compressor

globe reduce the size requirement

For ideally incompressible fluid, the mach number will be of the following produces maximum pressure difference for transportation of gases? The fluid property which matters for falling rain drops to acquire spherical shape is its A wastewater solution having a volume of 1000 L contains 0.21 kg phenol/m3 of solution. A total of 1.40 kg fresh granular activated carbon is added to the solution, which is then mixed thoroughly to reach equilibrium. What is the amount of phenol absorbed per kg carbon at equilibrium? The overhead product composition decreases with time in

0 vacuum pumps

1 blowers

pressure

height of descend

0.007 kg

0.106 kg

batch distillation with reflux

For a binary mixture with low relativity, continuous rectification to get pure products will require Chemisorption is

low reflux ratio

continuous distillation with reflux small cross-section

The stage efficiency in leaching depends on the

Weeping in distillation or absorption column

What are the two contacting phase in leaching?

the same as van der Waals time of contact between the solid and the solution increases tray efficiency

extract phase and raffinate phase Hydrogen sulfide is removed from water by contacting the solution with Distillation warm air. The operation is

characterized by adsorption of heat rate of diffusion of the solute through the solid and into the liquid provides larger surface for mass transfer solvent phase and solute phase Leaching

Disregarding the cost, which is the best solvent for the extraction of caproic acid acetic acid from an aqueous solution at 25deg C? Professional Regulations Commission was created under P.D. No. 223 A chemical engineer who designed and built a new type pf reactor and TRUE for three years, sold many units to the public can still patent his reactor.

chloroform

A person who has passed the Chemical Licensure Examination can take 18 his/her oath as a chemical engineer if his/her age is not less than _______ years. Which of the following is not a requirement for utility model inventive step registration? A section of the patent application containing detailed descriptions of disclosure the benefits obtained from using the invention is called the

19

A document issued by the DENR secretary indicating that the proposed Environmental project will cause significant negative environmental impact. Impact Statement

Environmental Compliance Certificate cement

In the Philippines, sulfur for sulfuric acid manufacturing is sourced from paper _______ industry. Sulfur is undesirable in petroleum because it causes engine knocking

P.D. No. 233 FALSE

novelty abstract

it increases the boiling pt of fuel

Materials added to detergent formulation to enhance cleaning performance by exhibiting synergistic cleaning effect with surfactant.

fillers

brighteners

Polyethylene is an example of _____________ polymerization

condensation

addition

Principal chemical conversion in the production of resin from monomer. condensation

hydration

Carbon black is added to rubber compounding as The binder for all the powder materials of paint A fibrous material left after cane sugar has been milled is commonly called as Molasses is a by product of raw sugar from the ______ process Kraft process is a common name for Water insoluble cell binders of wood DDT means

activator pigment bagasse

curing agent vehicle pulp

milling sulfate pulping pulp Diphenyldichlorotri phenylethane decoloration pigment make it corrosion resistant

extraction sulfite pulping cellulose dichlorodiphenyldic hloroethane hydrogenation dryer make glossy surface

thermoplastic

a monomer

Rancidity of oil can be reduced by Varnish does not contain Plasticisers are added to paints to

Silicone is

The process involved in converting rubber into a thin sheet or coating it extrusion on fabric is called Alkyl benzene sulfonate (ABS) is a detergent Neoprene is a monomer

mastication rubber synthetic rubber

Steam enters an adiabatic turbine at 10 MPa and 500 degC at a rate of 3 0.2348 kg/s and leaves at 0.1 MPa. If the power output of the turbine is 2 MW, determine the turbine efficiency. Work is a property of the system Throttling process is a reversible and isothermal process

0.3216

A sample consisting of 1.00 mole of Argon gas is expanded isothermally and reversibly at 0°C from 22.4L to 44.8L. The heat absorbed by the system is Maximum work can be obtained from a system when the change taking place in it is The ratio of work performed by a system and the heat it absorbed from a reservoir is referred to According to the first law of thermodynamics

0

+1.13 kJ

isothermal

adiabatic

Entropy

Gibb’s free energy

Energy is neither lost nor gained in any energy transformation.

Perpetual motion is possible.

In a 3-stage compressor system whose isentropic efficiencies are reported to be 0.75, 0.85 and 0.84, respectively, steam initially at 10 kPa is compressed to a final pressure of 500 kPa. The overall efficiency of the system is In choosing the refrigerant, the fluid must have the following characteristics, except

greater than 0.85

in between 0.75 and 0.85

environmentally benign

has a vapor pressure less than atmospheric

Coolers and boilers are ordinarily operated at ________ condition.

isobaric

isenthalpic

For an isolated system, maximum entropy will occur at A carnot cycle consists of

half-life two isothermal and two adiabatic process

critical condition two isochoric and two adiabatic process

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

sphericity

porosity

A measure of the ratio of the drag force acting on a unit area of the impeller & the inertial stress. Sulfuric acid is pumped at 3 kg/s through a 60-m length of smooth 25 mm pipe. If the pressure drop falls by one-half, what will be the new flow rate [kg/s]? Assume the following properties of sulfuric acid: SG = 1.84, viscosity = 25 cP. The equation del(P) = -(rho)(g) del(z) is known as the hydrostatic vertical law for which all the following assumptions are applied, except

Froude number

Reynold’s number

3

2

Which of the following can be adjusted by human operator in a closed feedback control loop?

set point

path function an irreversible and constant entropy

shear forces are not fluid is involved incompressible

controller output

The thermocouple is based on the Seebeck effect which states that a/an current _____ is generated when opposite junction of certain dissimilar pairs of wires are exposed to different temperatures. Dead time is a function of distance and momentum A pneumatic controller is used to control temperature within the range 2.83kPa/K 280K to 310K. The controller is adjusted so that the output pressure goes from 20kPa (valve fully open) to 105 Kpa (valve fully closed) as the measured temperature goes from 295K to 300K with the sent point held constant. What is the proportional gain?

temperature

The parameter which completely describes the behavior of the response to a disturbance of a second order system is the

damping coefficient

Time constant

acceleration 0.35kPa/K

C globe valve

D orifice

Comments! ! Un na nga ang gate valve. =P a

0.03

0.038 E

turbulent flow only

laminar flow only X

equal to the heat equal to the heat transfer coefficient transfer coefficient of equivalent to the the steam resistance offerred by the pipe

the minimum the amount of solvent number of stages used must be enough occur when the tie to form 2 phases. line coincides with an operating line. rectification

fractionation

minimum reflux

optimum reflux

mol/liter/min

liter/mol/min

xxx b

xxx

c

xxx

c

significant effect c

the heat transfer is the temperature is constant **panu pag iba na uniform throughout the cylinder **sinong ang heat transfer area?

! Meron gang f=64/Re? baka f = 12/Re eto eh "Hagen-Poiseuille Equation" for SMOOTH TUBES & LAMINAR FLOW from perry 8 same page ng nasa taas. xxx

d

E no effect

! The correct answer is about 0.0095 from perry 8th fig 6.9 pge 610 tingnan nyu pa

a

nanay mo?

k = (Volume

(order -1)

! 1/time ) / (Concentration(order -1)) x time

! Eh constant nga ung temp nung isang stream..=P btw.. ∆Tlm = [∆T(side a) - ∆T(side b)] / ln [∆T(side a) / ∆T(side b)] a-------------------->b a--------------------->b a-------------------->b a Solute = Solvent Unsaturated --> Solute < Solvent Supersaturated --> Solute > Solvent **based on solubility***

Sherwood, Reynold's and Schimdt No reduction ratio

Prandtl, Schimdt and Reynold's No classification ratio

the value of k is the reaction cannot independent of proceed **isa ka pa^^ the initial concentrations of A and B orifice **pabibilisin

c c

c

venturi **meter? hehe

! Look at p 5 - 63 to 5 -82 of perry 8th. Specifically, note the dimensionless numbers being used at every MTC formula. Nsh Nre Nsc ! Malamang =P ! Kelan ga naging dependent ang k sa initial concen ng kahit na alin sa reaction? Sa Temperature lang dependent ang k**. Kaya nga ang tawag sa k ay "specific rate constant" dahil specific sya sa isang temp at sa isang reaction at sya ay constant! Hehe **from Arrhenius eqn : lnk = - (E A / R) (1 / T) + lnk o ! Nozzle - ex. Pipe na papaliit ang diameter, papaliit din malamang ang cross sectional area, at papabilis ang velocity ng fluid.

nga, haharangan pa xD

a

***flow of incompresible fluids***

mass flowrate = density x Area x velocity a function of time not uniform throughout the reactor and varies from time to time book value market value

b

! Bacmix Reactor is another name for CSTRs (Constantly Stirred Tank Reactors) wherein ther is a constant composition throughout which is assumed due to constant stirring. xxx

b increases the amount of distillate the gas phase resistance is negligible

increases the condenser duty

Peclet, Stanton and Prandtl Nos

Schimdt, Peclet and Friction Nos

b

45-degree standard elbow **K = 0.35 compressor

square-corner elbow **K = 1.3

d

1" dia Drawn tubing

4" dia Riveted steel pipe

through each material is inversely proportional to the thickness of the material parallel reactions

is constant throughout the series of materials

the ratio of gas phase resistance to liquid resistance is approximately zero

accumulator

consecutive reactions

xxx ? xxx ?

! Sila yung gamitin sa Heat Transfer by convection. See perry 8th p 5.7, Heat transfer by conduction. Nu Nre NPr ! The higher the K (additional friction loss) the higher the pressure drop. See page 6 -18 perry 8th.

air

concret

humidification

extraction

b b

tangential pressure concentration gradient 113 deg F

static pressure

1.484 1.5

0.581 0.6

33.4

54.4

128 kg

32 kg

26.4

57.8

1.5

2.75

over 20 million

over 2 but less than 3

0.0454

0.0252

6930000

2040000

saturation temperature

dry-bulb temperature

75.26

78.5

momentum gradient

b c

146 deg F

b

c

the temperature increase in the of the air can also humidity of the air is be maintained insignificant constant 0.02

0.01

equilibrium moisture content tray drier

critical moisture content freeze drier

c c

air flow air flow parallel to the perpendicular to solid surface the surface of the solid

surface renewal

moisture diffusivity

2.129 hrs

3.42 hrs

0.01155

0.00116

decreases with time to use cross flow evaporation

no drying takes place

1.5

2.3

5

6

to use spray percolators

d

radiation

all of A, B and C

radiation

all of A, B and C

inverse of the total sum of the individual resistance resistances evaporation 451.7

all of A, B and C 475.1

5800

139200

5.51 m

4.14 m

966 kg

534 kg

85.8 sq.m.

88.5 sq.m.

a c c b

14 kPa

zero gauge

4.72

3.03

39

40

8

7

27.8

22.7

0.294

0.249

577

241

13.76

16.28

46.5

45.6

227.2

300

11994

20451

40130

45500

13.8

5

1163

19.4

4.67

2

95

100

7

0.52

31.7

37.1

851

900

0.75

1

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

25.2

20

3478

3750

0.714

6.01

100

25

13943 W

19343 W

23

33

38

0.038

both contain the same no of air molecules increases by about decreases. 40% stays constant. stays the same.

may increase or decrease. The application The application should should be rejected be given full because it violates consideration because both 1st and 2nd it does not violate any laws of Thermo. laws of Thermodynamics.

increases 8x.

increases 16x.

3 e7

5.2 e8

excess reactant reactant ratio

product yield fresh-feed conversion

c a

b b

Latent Heat of Condensation moisture Ultimate analysis O2-free basis Dulong's formula 32.48

Net Calorific Value volatile combustible matters Elemental analysis N2-free basis Oxygen unaccounted for equation 42.56

a b

b

2.38

6.13

absolute humidity 60% saturation of 0.05 PhP 434.16 PhP 450

0.03

0.05

4350

6000

9.5

17

0.9

0.92

51.2

22.76

7.86

23.1

1/conc 2

1/conc-time 1.5

adding a catalyst

removing the products of the reaction

the net equation

the rate law.

a

does not depend on the initial concentrations

is not a characteristic of the reaction

8

16

nature of reactants >0 log Ca vs reciprocal time lof Ca vs time

temperature

-ra = k Ca

-ra = k Cb^2

Law of Mass Action proportional to initial conc

Second Law of Thermo

85.3

99.1

231 s

768 s

19.1 min

10.4 min

8.33

9.33

52.63 m

56.23 m

0.3394

0.6197

c

d