Refresher Exam Questions Flashcards
A heat exchanger is to consist of a number of tubes each 25 mm diameter and 5 m long arranged in parallel. The exchanger is to be used as a cooler with a rating of 4 MW and the temperature wise in the water feed to the tubes is to be 20 deg K. Calculate the minimum number of tubes
A. 116 tubes
B. 130 tubes
C. 142 tubes
D. 85 tubes
A. 116 tubes
When a porous solid was dried under constant-drying conditions, 5 hours were required to reduce the moisture from 30 to 12 lb H2O.lb dry solid. Determine the time needed the time needed to dry the solid from 30 to 8 ln H2O/lb dry solid.
A. 3.34 hr
B. 7.74 hr
C. 1.25 hr
D. 2.88 hr
B. 7.74 hr
A rotary countercurrent dryer is fed with ammonium nitrate containing 5% moisture at the rate of 1.5 kg/s, and discharges the nitrate with 0.2% moisture. Calculate the mass of dry air passing through the dryer.
A. 1,6 kg/s
B. 2,4 kg/s
C. 3.8 kg/s
D. 6.1 kg/s
D. 6.1 kg/s
A rotary countercurrent dryer is fed with ammonium nitrate containing 5% moisture at the rate of 1.5 kg/s, and discharges the nitrate with 0.2% moisture. Calculate the humidity of the air leaving the dryer.
A. 0.0188 kg/kg
B. 0.0294 kg/kg
C. 0.08231 kg/kg
D. 0.0915
A. 0.0188 kg/kg
It is the angle at which a material will rest on pile
A. Angle of inclination
B. Angle of repose
C. Contact Angle
D. Banking Angle
B. Angle of Repose
It is partially decomposed plant matter that has accumulated underwater or in a water-saturated environment.
A. Oil shale
B. Tar Sands
C. Peat
D. Biomass
C. Peat
Which of the following is an ore of mercury
A. Bauxite
B. Galena
C. Spharelite
D. Cinnabar
D. Cinnabar
It is the most abundant metal of the earth’s crust.
A. Iron
B. Aluminum
C. Lithium
D. Sodium
B. Aluminum
Which of the following is a soft material
A. quartz
b. topaz
c. sapphire
d. gypsum
d. gypsum
When the temperature of the surrounding is higher than the blood temperature of a human body then the transfer of heat will between the body and the sorrounding
a. convection
b. radiation
c. cooling
d. evaporation
A. convection
It is frequently caused by crystallization of a material whose solubility at the wall temperature is lower than at the bulk liquid temperature
a. scaling
b. salting
c. fouling
a. scaling
It is a nonporous rock containing organic kerogen.
a. tar sands
b. natural gas
c. oil shale
c. oil shale
What is produced when calcium carbibe is mixed with water
acetylene
What is the chemical formula of alar
C6H12N2O3
How many liters is 27000 fluid barrels
3.22E6
How many liters is 27000 oil barrels
4.29E6
A cylindrical bucket 150 mm in diameter and 200 m high contains 150 mm of water. A boy swings the bucket on a vertical plane so that the bottom of the bucket describes
a. 24.22 rpm
b. 31.13 rpm
c. 38.88
b. 31.13
Calculate the volume of an octahedron whose length of sides are 2 m each.
a. 1.77 m3
b. 2.45 m3
c. 3.77 m3
c. 3.77 m3
Calculate the absolute entropy of solid NH3 at its melting point at 1 atm pressure, in Btu/lb-R. Boiling point = -33.4C melting point = -77.7C
A. 0.6066
B. 0.8244
C. 1.2288
0.6066
Calculate the change in entropy when 1 lb of NH3 at its melting point at 1 atm pressure, in Btu/lb-R. Boiling point = -33.4C melting point = -77.7C
A. -2.463
B. -1.655
C. 1.859
A. -2.463
Calculate the change in entropy when 1 lb of NH3 liquid will change to solid at its melting point at 1 atm pressure, in Btu/lb-R. Boiling point = -33.4C melting point = -77.7C
A. -0.407
B. -1.005
C. -1.776
A. -0.407
Establish the separation capability of a single-stage (differential) batch still processing a mixture of two compounds having a relative volatility.
A. 450 mol
B. 520 mol
C. 640 mol
D. 725 mol
D. 725 mol
From the data in #29, what is the mole fraction A in the distillate
A. 0.75
B. 0.70
C. 0.65
A. 0.75
If a right circular cone is cut parallel with the axis of symmetry, it will reveal a/an
Hyperbola
Location 1 is 3m away from location 2. A man walks 4 m and 40 degrees to location 3. How far is location 3 location 2.
A. 2.57 m
B. 3.42 m
C. 4.18 m
A. 2.57m
If the second derivative of the equation of a curve is equal to the negative of the equation of that same curve, the curve is
a. an exponential
b. a tangent
c. a sinusoid
c. a sinusoid
The highest ordinate on the stress-strain curve
A. ultimate strength
B. rupture point
Ultimate strength
Which does not belong to the group
A. microjoule
B. Watts
C. Kilowatt-hour
B. Watts
What is the molecular weight of sucrose
C12H22O11 - 342
Who coined the term serendipity
Horace Walpole
Who discovered radioactivity
Henri Becquerel
Which control system is used for multi-input, multi-output system?
model predictive control
A control structure with two feedback controller with the output of the primary controller changes the set point of the secondary controller whose output goes to the final controller
cascade control
In a process in which it is used as solvent, benzene is evaporated into dry nitrogen. at 297 K and 101.3 kPa, the resulting mixture has a percentage relative humidity of 60. it is required to recover 80 percent of the benzene present by cooling to 283 K and compressing to a suitable pressure. What should be this pressure be?
A. 120 kpa
b. 210 kpa
c. 392 kpa
C. 392 kpa
A boiler plant raises 5.2 kg/s of steam at 1825 kN/m2 pressure, using coal of calorific value 27.2 Mj/kg. if the boiler efficiency is 75%, how much coal is consumed per day? If the steam is used to generate electricity, what is the power generation in kilowatts assuming a 20% conversion efficiency of the turbines an generators
A. 0.713 kg/s; 3MW
B. 1.322 kg/s, 4.5 MW
C. 2.144 kg/s, 1.5 MW
A. 0.713; 3 MW
A benzene toluene feed (withh 40 mol % benzene and 60 mol % toluene) to a distillation column is at a temperature of 20C. The molar heat capacity of the feed is 159.2 kJ/kmol-K. Molar heat of vaporizations of benzene and toluene are 30.813 and 33.325 kJ/kmol. The slope of the feed line is closest to
A. 0
B. 1
C. 3.7
C. 3.7