ChE Concepts Flashcards
1
Q
Ratio of thermal conductivity to thermal capacity
A
Thermal diffusivity (α = k/ρCₚ in m²/s)
2
Q
Packed columns are best used for _____
A
Corrosive liquids
Foaming materials
High flowrates
Cost efficiency
3
Q
Describe the reaction of the inversion of cane sugar
A
Pseudo-first order, second order reaction
4
Q
Describe the reaction of the cracking of crude oil
A
Heterogenous catalytic
5
Q
Most widely used screw thread standard
A
ISO
6
Q
Impure product obtained by partial purification of potash from wood ashes
A
Pearl ash or potassium carbonate
7
Q
Residue from wine vats, also called potassium tartrate
A
Argol
8
Q
Formation of smallest aggregate of molecules in a supersaturated solution capable of growing into a large precipitate particle
A
Nucleation
9
Q
Nucleation due to presence of foreign substance
A
Heterogeneous nucleation
10
Q
Nucleation due to existing crystals
A
Secondary nucleation
11
Q
4 stages in the selection process for choosing the best design
A
- Possible designs (credible) - w/n external constraints
- Plausible designs (feasible) - w/n internal constraints
- Probable designs: likely candidates
- Best design (optimum) - best solution
12
Q
Method of water softening that uses zeolites
A
Permutit
13
Q
Equation for schedule number
A
Sch No = 1000 P/S
P = operating pressure
S = allowable stress
14
Q
Refers to waste or scrap glass, usually ground
A
Cullet
15
Q
For any closed system formed initially from given masses of prescribed chemical species, by any two properties of the system, provided that these two properties are independently variable at the equilibrium state.
A
Duhem’s Theory
16
Q
A device substantially without moving parts, in which a fuel, such as H₂, natural gas, methanol, or propane, can be converted directly into twice the quantity of electrical energy that would result from the usual boiler-turbine power generation
A
Fuel Cell
17
Q
Equivalent of 1 ton of refrigeration capacity in BTU/min
A
1 ton of refrigeration capacity = 200 BTU/min
18
Q
At the exit of a nozzle, pressure is ____, and velocity is ____.
A
low pressure, high velocity
19
Q
The Buckingham Pi-theorem is applied to
A
Dimensional Analysis
20
Q
The achievement of a temperature below that of the intermediate surroundings
A
Refrigeration
21
Q
Throttling process is _____
A
Isenthalpic
22
Q
Solid with no orderly structure
A
Amorphous
23
Q
The union of the nonvolatile inorganic oxides resulting from the decomposition and fusion of alkali and alkaline earth compounds, sand, and other constituents, ending in a product with random atomic structure.
A
Glass
24
Q
An early method for production of sodium carbonate from NaCl, calcium carbonate, and H₂SO₄
A
Leblanc Process
25
Industrial process for production of H₂SO₄. Based on oxidation of S to SO₃ on a vanadium oxide catalyst followed by reaction with water in fuming H₂SO₄
Contact Process
26
Method for underground mining of sulfur
Frasch Method
27
Conversion of H₂S to pure sulfur
Claus Process
28
Catalyst used in burning of SO₂
Vanadium Pentoxide (V₂O₅)
29
Catalyst for ammonia oxidation
Pt or Pt-Ir
30
It is amount of energy in excess of the average energy level which the reactants must have in order for the reaction to proceed
Activation energy
31
Value of change in internal energy when a thermodynamic system undergoes a cyclic process
Zero
32
Parameter which completely describes the behavior of the response to a disturbance of a 2nd order system
Damping coefficient
33
Damping coefficient of a critically damped system
1
34
Heating of an ore to bring about reaction with the furnace atmosphere
Smelting
35
Device used for classification of particles with size ranges below 10 micrometers
Centrifuge
36
Medium which can trap particles of size 0.005 micrometer
Membrane
37
Process in which H₂S is removed from H₂O by contacting the solution with warm air.
Stripping
38
Result of the presence of sulfur in petroleum
Engine knocking
39
Third aspect in plant design
Environment
40
Lowest temperature at which the material will ignite from an open flame
Flash point
41
Lanolin, which is widely used in cosmetics, is derived from
Sheep's wool
42
How can you increase the life of an incandescent lamp?
Fill with argon gas
43
Dimensionless number concerned with heat transfer in laminar flow
Graetz number
44
Dimensionless number concerned with natural convection
Grashof number
45
Mass transfer in a flowing fluid may be correlated by ____
Sherwood, Reynolds, and Schmidt numbers
46
The terms sweet and sour in natural gas are used to denote the absence or presence of ____
H₂S
47
Neoprene is a _____
Synthetic rubber
48
Water insoluble cell binders of wood
Lignin
49
Rancidity of oil can be reduced by ____
Hydrogenation
50
Purpose of plasticizers in paint
Corrosion resistance
51
Varnish does not contain ____
Pigment
52
In the Philippines, S for H₂SO4 manufacturing is sourced from what industry?
Paper
53
Identification of pipelines carrying different liquids and gases is done by ____
Color
54
Dimensionless quantity, which for fluids flowing inside tubes, regarded as ratio of shear stress (at tube wall) to kinetic energy
Fanning Friction Factor
55
Other term for CaO
Quicklime
56
Other term for Ca(OH)₂
Hydrated lime or slaked lime
57
Chemical released during the Bhopal tragedy
Methyl isocyanate
58
Under the same temperature gradient across various metal plates of the same thickness, the heat conducted per unit of surface area will be largest across what metal?
Copper
59
If a man touches two metals which were kept together at room temperature, why could one metal feel colder than the other?
One has higher thermal conductivity
60
Cork is a good insulator because it has ____
A porous body
61
The insulation ability of a material with the presence of moisture would _____
Decrease
62
Heat transfer in turbulent flow may be described by an empirical equation correlating _____
Nusselt, Prandtl, and Reynolds number
63
Steady-state temperature reached by a small amount of liquid evaporating into a large amount of unsaturated vapor-gas mixture
Wet bulb temperature
64
The temperature at which the moisture in humid air exerts a partial pressure equal to its vapor pressure is the
Dew Point
65
The viscosity of a gas ____ with temperature
Increases
66
The force exerted by the fluid on the solid opposite to the direction of flow
Drag
67
Order of reaction in which the rate is independent of the concentration of the reactants
Zeroth order
68
Order of reaction in which the rate is independent of the initial concentration
First order
69
TRUE or FALSE: From Arrhenius Law, the value of the frequency factor, ko, affects the temperature sensitivity
False
70
Reactor characterized by the variation in extent of reaction and properties of mixture with time
Batch Reactor
71
Reactor characterized by presence of lateral mixing
Plug Flow Reactor
72
Byproduct of the sugar/ethanol industry
Vinasse
73
Represents the total mass transferred by molecular diffusion
Sherwood number
74
A dimensionless number that represents the ratio of the molecular momentum diffusion to the molecular mass diffusivity
Schmidt number
75
The only strength of stress grade lumber that can be precisely determined without breaking the piece
Stiffness
76
The chief difference between exterior grade plywood and interior grade plywood
Type of glue used
77
Warp, wane and checks are all factors that help determine the quality of
Stress-grade lumber
78
The Brinell Number of a material measures
Hardness
79
A major classification group of stainless steels 6% to 22% nickel in addition to 16% to 26% chromium. This group differs from the other two major groupings in that its alloys are ____
Non-magnetic
80
The ultimate strength divided by the allowable stress
Factor of safety
81
If an engineering structure is to be designed against the rupture of any of its members under steady load, the factor of safety is a ratio based on working stress and ____
Ultimate strength
82
The offset method is used to find a property of metals that do not have a well-defined stress-strain curve such as steel. This property is called ____
Yield point
83
In boiler calculations, the rivet is assumed to ____
Fill the hole after driving
84
The intermittent welds generally used to hold materials in place temporarily
Double vee
85
In the construction of a vinegar container tank, which of these metals of construction is not recommended: aluminum, stainless steel, brass, monel
Brass
86
Bracket supports are most suitable for ____
Thick walled vertical vessels
87
Skirt support is most suitable for ____
Tall horizontal vessel
88
Design based on conditions giving least cost per unit time and max profit per unit production
Optimum economic design
89
A flow diagram, indicating the flow of materials, unit operations involved, equipment necessary and special information on operating temp and pressure
Qualitative flow diagram
90
In a plant design implementation, soil testing is done to determine the ____
Load bearing capacity
91
This involves all engineering aspects in the development of either a new, modified, or expanded industrial plant
Plant Design
92
A chemical engineer specializing in the economic aspects of design
Cost Engineer
93
Actual design of the equipment and facilities necessary for carrying out the process
Process Design
94
The final step before developing construction plans for the plant and includes complete specifications for all components of the plant and accurate costs based on quoted prices
Firm process design
95
A thorough systematic analysis of all factors that affect the possibility of success of a proposed undertaking usually with the market, technical, financial, socio-economic and management aspects
Project feasibility study
96
Discusses the nature of the product line, the technology necessary for production, its availability, the proper mix of production resources and the optimum production volume
Technical feasibility
97
Discusses the nature of the unsatisfied demand which the project seeks to meet, its growth and the manner in which it is to be met
Market feasibility
98
Simplest mode of control characterized by a two-position control commonly utilized in a thermostat for controlling the temperature of heaters, air conditioners, ref, etc.
On-off control
99
Control system in which the control action is independent of the output
Open loop system
100
Control system in which the control action is somehow dependent on the output
Closed loop system
101
An arrangement of physical components connected or related in such a manner as to command direct, regulate itself or another system
Control system
102
Property of a closed-loop system which permits the output to be compared with the input to the system so that the appropriate control action may be formed
Feedback control system
103
A frequency response measure of how well the system responds to variations in the input signal
Bandwidth
104
A signal defined at, or of interest at, only discrete instants of the variable
Digital signal
105
A device that converts an analog or continuous signal into a discrete/digital signal
Analog to digital converter
106
Convert one signal or energy form into another
Transducer
107
Part of the deviation of the response which approaches zero as time approaches infinity
Steady-state response
108
Integral of a unit step function
Ramp function
109
A sensor usually made of a semiconductor that utilizes the effect of temperature on the resistance to current is called
Thermistor
110
Integral of a Dirac function
Step function
