LE 2 - Transport Processes and Unit Operations Flashcards
is states that the mass entering is equal to the mass leaving plus the mass left in the process
law of conservation of mass
This is a special case of heat transfer, which deals with the evaporation of a volatile solvent such as water from a nonvolatile solute such as salt or any other material in solution.
Evaporation
These ____________________ are common to all types of diverse process industries.
Unit Operations
In process engineering, which often takes place at constant pressure, electrical energy, kinetic energy, potential energy, and work either are not present or can be neglected. Then only the enthalpy of the materials (at constant pressure), the standard chemical reaction energy, and the heat added or removed must be taken into account in the energy balance. This is generally called a?
heat balance
The __________________ of a substance is defined as the amount of heat necessary to increase the temperature by 1 degree.
heat capacity
To solve a material-balance problem it is advisable to proceed by a series of definite steps, as listed below.
- Sketch a simple diagram of the process
- Write the chemical equations involved (if any)
- Select a basis for calculation
- Make a material balance
When chemical reactions occur in the balances (as discussed in Section 1.5D), one should use
kg mol units
At present, the ______________ has been adopted officially for use exclusively in engineering and science
SI system
are almost always represented in terms of mole fractions and not weight fractions
gas mixtures
What are the three main systems of basic units employed at present in engineering and science?
- SI (Système International d’Unités) system
- English System
- CGS System
Methods of Expressing Temperatures and Compositions
- Temperature
- Gas-Law Constant
- Ideal Gas Mixtures
- Vapor Pressure and Boiling Point of Liquids
basic unit of heat
joule
The standard preferred unit of time is the
second (s)
For engineering purposes, ________________________ is sufficiently accurate to use for actual mixtures at total pressures of a few atmospheres or less.
Dalton’s law
energy can appear in many form, and some of the common forms are?
- enthalpy
- electrical energy
- chemical energy
- kinetic energy
- potential energy
- work
- heat inflow
in making material balances, we used the?
law of conservation of mass
Unit operations where momentum transfer occurs?
- fluid flow
- sedimentation
- mixing
In this process a component of a gas or a liquid stream is removed and adsorbed by a solid adsorbent.
Adsorption
is defined as the amount of heat needed to raise 1.0 lb water at 1 degrees Fahrenheit
btu (British thermal unit)
The vapor pressure of a liquid increases markedly with?
temperature
This law, stated simply, says that mass cannot be created or destroyed (excluding, of course, nuclear or atomic reactions). Hence, the total mass (or weight) of all materials entering any process must equal the total mass of all materials leaving plus the mass of any materials accumulating or left in the process.
Law of Conservation of Mass
it represent the sum of the internal energy plus the pressure-volume term
enthalpy (H)
The unit operation ________________ is used to purify or separate alcohol in the beverage industry and hydrocarbons in the petroleum industry.
distillation
This concerns the principles that determine the flow or transportation of any fluid from one point to another.
Fluid Flow
includes distillation, absorption, liquid-liquid extraction, membrane separation, adsorption, and leaching
Mass Transfer
The value of the vapor pressure is _________________________ of the amount of liquid in the container as long as some is present.
independent
basic quantity used in the SI system in the unit of an element is the
kilogram mole (kg mol)
This is concerned with the transfer of momentum in moving media, such as in the unit operations of fluid flow, sedimentation, and mixing.
Momentum Transfer
Temperatures are defined in
kelvin (K)
few of the standard prefixes for multiples of the basic unit are as follows:
- giga (G)
- mega (M)
- kilo (K)
- centi (c)
- milli (m)
- micro (µ)
- nano (n)
We can take these seemingly different chemical, physical, or biological processes and break them down into a series of separate and distinct steps called
Unit Operations
One of the basic laws of physical science is the
law of conservation of mass
Unit operations where mas transfer occurs?
- distillation
- absorption
- liquid-liquid extraction
- membrane separation
- adsorption
- leaching
This concerns the removal of a solute such as a salt from a solution by precipitating the solute from the solution.
Crystallization
basic quantity used in the SI system in the unit of time is the
second (s)