ChE Principles Flashcards
Which of the following is an example of pseudo plastic fluid?
a. apple sauce c. tap water
b. rubber latex d. sewage sludge
A. apple sauce
What controllers are frequently installed not because all modes of control are required but more of their versatility in systems which respond rather sluggishly?
a. PI Control c. PD Control
b. Integral Control d. PID control
B. Integral Control
What is the simplest type of control commonly expressed as having on/off position action?
a. Integral c. Bang-Bang
b. Manual d. Input-Output
C. Bang-Bang
In feedback control system for temperature control, a thermocouple measures the temperature and the output is fed to a controller. What results when one of the components known as a comparator compares a measured temperature value with desired value or set point?
a. Deviation c. Oscillation
b. Error d. Feedback
B. Error
In the gasification of coal to produce substitute natural gas, at what reaction zone is methane produced when some of the carbon is hydrogenated?
a. Distillation Zone c. Combustion Zone
b. Gasification d. Pyrolysis
B. Gasification
A scientist who used zeolites for water softening process.
a. Robert Gans c. Axel Cronstedt
b. Bob Guccione d. Joseph Culligan
a. Robert Gans
This type of flow-measuring device is typically used for highly corrosive fluids.
a. Rotameter c. Orifice meter
b. Coriolis flowmeter d. Magmeter
b. magmeter
What is the minimum temperature at which a vapor above a liquid will continue to burn once ignited?
a. Explosive limit c. Flammability limit
b. Fire point d. Flash point
B. Fire Point
The work done in a free expansion process is
Zero
In plant design, what is a protective response which is initiated upon detection of a process hazard?
Interlock
A disturbance which is externally applied to the system.
Perturbations
Which among the following is not an exothermic process?
a. Methanol synthesis c. Oxidation of sulfur
b. Catalytic cracking d. Ammonia synthesis
Catalytic cracking
It is most efficient process for hydrogen gas production which emits less amount of carbon.
Steam Reforming
Oil shale is an organic-rich fine-grained sedimentary rock also known as
Kerogen
Actual work delivered divided by theoretical work?
Turbine Efficiency
What happen to the particle when grinding limit is reached?
a. dust explosion c. change in shape
b. no change in particle size
d. it becomes powder
no change in particle size
Other name for Yamatake system
azbil
For a zero-order reaction, the ratio of the volume of a backmix reactor to the volume of a plugflow reactor, for the same reactant conversion and conditions, is:
1
A product of alumina and silica at high temperature.
kaolinite
A substance which can be readily converted into dye or other colored compound.
a. anlagen c. goitrogen
b. acrogen d. chromogen
Chromogen
Skirt supports are most suitable for:
a. Thick-walled vertical vessels c. Horizontal vessels
b. Thin spherical vessels d. Tall vertical vessels
Tall Vertical Vessels
A valve that controls flow by means of a disk or wedge-shaped dam sliding at right angles to the direction of flow and seating tightly in the valve body is a
gate valve
The friction factor for flow through a pipe with relative roughness of 0.004 at a Reynold’s No. of 80,000 is approximately equal to
0.03
The equation that relates friction factor and Reynold’s No., f=64/Reynold’s No. holds for
a. smooth pipes
b. laminar and turbulent flow
c. turbulent flow only
d. laminar flow only
d. laminar flow only
The enrichment of the vapor steam as it passes through the column in contact with the reflux during distillation is called
rectification
The maximum number of plates for a given distillation system is obtained at
minimum reflux
For a cylinder where steady-state radial heat transfer takes place
a. the heat flux is constant
b. maximum heat transfer rate occurs at the surface
c. the heat transfer is constant
d. the temperature is uniform throughout the cylinder
c. the heat transfer is constant
Crystallization occurs in a solution that is
supersaturated
Mass transfer in a flowing fluid may be correlated by
a. Sherwood, Nusselt and Reynold’s No
b. Peclet, Reynold’s and Schimdt No
c. Sherwood, Reynold’s and Schimdt No
d. Prandtl, Schimdt and Reynold’s No
c. Sherwood, Reynold’s and Schimdt No
A device for increasing the velocity of a fluid in steady flow is a
nozzle
Which one among the following materials has the best insulating property?
window glass
wood
air
concrete
wood
Oil flows under laminar conditions inside a steam heated copper pipe. The overall heat transfer coefficient is approximately
equal to the heat transfer coefficient of the steam
On one side of a heat exchanger where either a condensing 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
significant effect
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
a. separation plate
b. theoretical plate
c. transition plate
d. bubble plate
d. bubble plate
Reactions whereby reactants proceed along several paths and give different products are
a. polymeric reactions
b. reversible reactions
c. parallel reactions
d. consecutive reactions
parallel reactions
For mass transfer to take place, there must be a
a. phase change
b. reaction component
c. concentration gradient
d. momentum gradient
concentration gradient
A carnot cycle consists of
two isothermal and two adiabatic process
This is also known as the volume fraction of the voids in packed beds.
porosity
Coolers and boilers are ordinarily operated at ________ condition.
isobaric
For an isolated system, maximum entropy will occur at
a. half-life
b. critical condition
c. equilibrium
d. start of the process
equilibrium
A measure of the ratio of the drag force acting on a unit area of the impeller & the inertial stress.
power number
Which of the following can be adjusted by human operator in a closed feedback control loop?
set point
controller output
process variable
load variable
set point
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.
current
temperature
emf
resistance
emf
Dead time is a function of distance and
a. momentum
b. acceleration
c. time
d. velocity
velocity
The parameter which completely describes the behavior of the response to a disturbance of a second order system is the
damping coefficient
According to the first law of thermodynamics
Energy is neither lost nor gained in any energy transformation.
The ratio of work performed by a system and the heat it absorbed from a reservoir is referred to
carnot efficiency
Maximum work can be obtained from a system when the change taking place in it is
reversible
Throttling process is
constant enthalpy process
Work is a
a. property of the system
b. path function
c. state function
d. state description of a system
path function
Neoprene is a
synthetic rubber
Silicone is
a. thermoplastic
b. a monomer
c. an inorganic polymer
d. thermosetting plastic
an inorganic polymer
Plasticizers are added to paints to
give elasticity and prevent cracking of the film
Varnish does not contain
pigment
Rancidity of oil can be reduced by
hydrogenation
Molasses is a by product of raw sugar from the ______ process
evaporation
Polyethylene is an example of _____________ polymerization
addition
Principal chemical conversion in the production of resin from monomer.
alkylation
Carbon black is added to rubber compounding as
activator
Sulfur is undesirable in petroleum because
it causes engine knocking
In the Philippines, sulfur for sulfuric acid manufacturing is sourced from _______ industry.
a. paper
b. cement
c. petroleum
d. detergents
Paper
Professional Regulations Commission was created under P.D. No. 223 P.D. No. 233 P.D. No. 232 P.D. No. 826
P.D. No. 223
Hydrogen sulfide is removed from water by contacting the solution with warm air. The operation is
Distillation
Leaching
Absorption
Stripping
Stripping
What are the two contacting phase in leaching?
a. extract phase and raffinate phase
b. solvent phase and solute phase
c. feed phase and solvent phase
d. overflow and underflow
overflow and underflow
which of the following produces maximum pressure difference for transportation of gases? vacuum pumps blowers fans compressors
compressors
The most economical valve for use with large diameter pipes.
butterfly valve
To increase the life of an incandescent lamp is
filled with argon gas
Trace metal that causes the Minamata disease.
Hg (Mercury)
A criteria pollutant responsible for the reddish brown color of smog.
NO2
It refers to waste or scrap glass, usually ground
Cullet
From what mineral is radium obtained?
Pitch blend
An apparatus used to measure atmospheric pressure.
barometer
____ is normally used to determine the quality of combustion gases
Orsat Analysis
Hydrogen in fuel which needs oxygen from air for its combustion is known as
Net Hydrogen
Refers to the outgoing stream of noncombustible matter (ash), which separates from the materials that can be gasified.
Refuse
Which of the following is true if the resulting combustible lost in refuse is coked coal?
A. has lost only its moisture
B. has lost both moisture and VCM content
C. has FC and VCM as its main constituent
D. the FC/VCM in green coal is equal to FC/VCM in refuse
B. has lost both moisture and VCM content
A gas which contains saturated paraffin hydrocarbons.
Natural Gas
Combined water is equal to
oxygen in the fuel
Burning coke in a limited supply of oxygen can result in the formation of
CO
When water in the products of combustion is in the vapor state, the heating value is
lower heating value
It refers to the internal heat from the earth
geothermal
It is usually applied to cooling below ambient temperature.
refrigeration
Carbonate, or temporary hardness, is caused by bicarbonates of
calcium and magnesium
It is the term applied to processes which remove or reduce the hardness of water.
softening
It is a linear polymer which may reversible softened by heat and solidified by cooling.
thermoplastics
The statement where electrons are added to orbitals of equal energy, a single electron will enter each orbital before a second one enters any one orbital, with the spins remaining parallel if possible.
Hunds rule
A relation stating that when two relations are added to give a third reaction, the corresponding enthalpies of reaction must also be added.
Hess’s law
The amount the system output response proceeds beyond the desired response
overshoot
if the pressure recovery experienced by the liquid is enough to raise the pressure above the vapor pressure of the liquid , then the vapor bubbles start collapsing or imploding. the implosion is called
cavitation
Third aspect in plant design
environment
A device used for the classification of particles in size ranges below 10 micrometer.
centrifuge
It is an alloy containing copper and zinc
Brass
A type of screening equipment operated with a shaking motion, a long stroke at low frequency
reciprocating screens
Which of the following filter media can be trapped particles of size 0.005 micrometer?
membranes
An equipment used to separate liquids where there is a sufficient differences in density between the liquids for the droplets to settle readily
decanters
A pipe has 2 inch inlet and has a 4 inch outlet, the mass flow ratio of the inlet is___ to that of the outlet.
equal
Point velocities can be measured using
pitot tube
Which of the following has the highest thermal conductivity? A. mercury B. gasoline C. water D. alcohol
A. Mercury
What happens to the thermal conductivity of diatomic gases if the temperature is increase?
it will also increase
The boiling point of a given solution is a linear function of a boiling point of pure water at the same pressure
Duhring’s rule
