ChE Concepts Flashcards
Ratio of thermal conductivity to thermal capacity
Thermal diffusivity (α = k/ρCₚ in m²/s)
Packed columns are best used for _____
Corrosive liquids
Foaming materials
High flowrates
Cost efficiency
Describe the reaction of the inversion of cane sugar
Pseudo-first order, second order reaction
Describe the reaction of the cracking of crude oil
Heterogenous catalytic
Most widely used screw thread standard
ISO
Impure product obtained by partial purification of potash from wood ashes
Pearl ash or potassium carbonate
Residue from wine vats, also called potassium tartrate
Argol
Formation of smallest aggregate of molecules in a supersaturated solution capable of growing into a large precipitate particle
Nucleation
Nucleation due to presence of foreign substance
Heterogeneous nucleation
Nucleation due to existing crystals
Secondary nucleation
4 stages in the selection process for choosing the best design
- Possible designs (credible) - w/n external constraints
- Plausible designs (feasible) - w/n internal constraints
- Probable designs: likely candidates
- Best design (optimum) - best solution
Method of water softening that uses zeolites
Permutit
Equation for schedule number
Sch No = 1000 P/S
P = operating pressure
S = allowable stress
Refers to waste or scrap glass, usually ground
Cullet
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.
Duhem’s Theory
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
Fuel Cell
Equivalent of 1 ton of refrigeration capacity in BTU/min
1 ton of refrigeration capacity = 200 BTU/min
At the exit of a nozzle, pressure is ____, and velocity is ____.
low pressure, high velocity
The Buckingham Pi-theorem is applied to
Dimensional Analysis
The achievement of a temperature below that of the intermediate surroundings
Refrigeration
Throttling process is _____
Isenthalpic
Solid with no orderly structure
Amorphous
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.
Glass
An early method for production of sodium carbonate from NaCl, calcium carbonate, and H₂SO₄
Leblanc Process
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
Method for underground mining of sulfur
Frasch Method
Conversion of H₂S to pure sulfur
Claus Process
Catalyst used in burning of SO₂
Vanadium Pentoxide (V₂O₅)
Catalyst for ammonia oxidation
Pt or Pt-Ir
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
Value of change in internal energy when a thermodynamic system undergoes a cyclic process
Zero
Parameter which completely describes the behavior of the response to a disturbance of a 2nd order system
Damping coefficient
Damping coefficient of a critically damped system
1
Heating of an ore to bring about reaction with the furnace atmosphere
Smelting
Device used for classification of particles with size ranges below 10 micrometers
Centrifuge
Medium which can trap particles of size 0.005 micrometer
Membrane
Process in which H₂S is removed from H₂O by contacting the solution with warm air.
Stripping
Result of the presence of sulfur in petroleum
Engine knocking
Third aspect in plant design
Environment
Lowest temperature at which the material will ignite from an open flame
Flash point
Lanolin, which is widely used in cosmetics, is derived from
Sheep’s wool
How can you increase the life of an incandescent lamp?
Fill with argon gas
Dimensionless number concerned with heat transfer in laminar flow
Graetz number
Dimensionless number concerned with natural convection
Grashof number
Mass transfer in a flowing fluid may be correlated by ____
Sherwood, Reynolds, and Schmidt numbers
The terms sweet and sour in natural gas are used to denote the absence or presence of ____
H₂S
Neoprene is a _____
Synthetic rubber
Water insoluble cell binders of wood
Lignin
Rancidity of oil can be reduced by ____
Hydrogenation
Purpose of plasticizers in paint
Corrosion resistance
Varnish does not contain ____
Pigment
In the Philippines, S for H₂SO4 manufacturing is sourced from what industry?
Paper
Identification of pipelines carrying different liquids and gases is done by ____
Color
Dimensionless quantity, which for fluids flowing inside tubes, regarded as ratio of shear stress (at tube wall) to kinetic energy
Fanning Friction Factor
Other term for CaO
Quicklime
Other term for Ca(OH)₂
Hydrated lime or slaked lime
Chemical released during the Bhopal tragedy
Methyl isocyanate
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
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
Cork is a good insulator because it has ____
A porous body
The insulation ability of a material with the presence of moisture would _____
Decrease
Heat transfer in turbulent flow may be described by an empirical equation correlating _____
Nusselt, Prandtl, and Reynolds number
Steady-state temperature reached by a small amount of liquid evaporating into a large amount of unsaturated vapor-gas mixture
Wet bulb temperature
The temperature at which the moisture in humid air exerts a partial pressure equal to its vapor pressure is the
Dew Point
The viscosity of a gas ____ with temperature
Increases
The force exerted by the fluid on the solid opposite to the direction of flow
Drag
Order of reaction in which the rate is independent of the concentration of the reactants
Zeroth order
Order of reaction in which the rate is independent of the initial concentration
First order
TRUE or FALSE: From Arrhenius Law, the value of the frequency factor, ko, affects the temperature sensitivity
False
Reactor characterized by the variation in extent of reaction and properties of mixture with time
Batch Reactor
Reactor characterized by presence of lateral mixing
Plug Flow Reactor
Byproduct of the sugar/ethanol industry
Vinasse
Represents the total mass transferred by molecular diffusion
Sherwood number
A dimensionless number that represents the ratio of the molecular momentum diffusion to the molecular mass diffusivity
Schmidt number
The only strength of stress grade lumber that can be precisely determined without breaking the piece
Stiffness
The chief difference between exterior grade plywood and interior grade plywood
Type of glue used
Warp, wane and checks are all factors that help determine the quality of
Stress-grade lumber
The Brinell Number of a material measures
Hardness
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
The ultimate strength divided by the allowable stress
Factor of safety
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
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
In boiler calculations, the rivet is assumed to ____
Fill the hole after driving
The intermittent welds generally used to hold materials in place temporarily
Double vee
In the construction of a vinegar container tank, which of these metals of construction is not recommended: aluminum, stainless steel, brass, monel
Brass
Bracket supports are most suitable for ____
Thick walled vertical vessels
Skirt support is most suitable for ____
Tall horizontal vessel
Design based on conditions giving least cost per unit time and max profit per unit production
Optimum economic design
A flow diagram, indicating the flow of materials, unit operations involved, equipment necessary and special information on operating temp and pressure
Qualitative flow diagram
In a plant design implementation, soil testing is done to determine the ____
Load bearing capacity
This involves all engineering aspects in the development of either a new, modified, or expanded industrial plant
Plant Design
A chemical engineer specializing in the economic aspects of design
Cost Engineer
Actual design of the equipment and facilities necessary for carrying out the process
Process Design
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
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
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
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
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
Control system in which the control action is independent of the output
Open loop system
Control system in which the control action is somehow dependent on the output
Closed loop system
An arrangement of physical components connected or related in such a manner as to command direct, regulate itself or another system
Control system
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
A frequency response measure of how well the system responds to variations in the input signal
Bandwidth
A signal defined at, or of interest at, only discrete instants of the variable
Digital signal
A device that converts an analog or continuous signal into a discrete/digital signal
Analog to digital converter
Convert one signal or energy form into another
Transducer
Part of the deviation of the response which approaches zero as time approaches infinity
Steady-state response
Integral of a unit step function
Ramp function
A sensor usually made of a semiconductor that utilizes the effect of temperature on the resistance to current is called
Thermistor
Integral of a Dirac function
Step function
