Unit Conversions
This is how many cubic centimeters are in a cubic meter.
1,000,000
For any mixture, the total mole composition will always be equal to this number
What is 1?
This is what DOF analysis does.
What is specify the state of the system? That is, determine if we have all the information we need or not.
m refers to one measure, while m* refers to another measure
(* represents a dot)
What is mass and mass flowrate?
What is batch?
25 degrees Celsius is equal to this quantity in degrees Fahrenheit
What is 77?
Two species are specified as having mass fractions of 0.372 and 0.481 in a three component stream. This is the mass fraction of the third species.
What is 0.147? (1 - 0.372 - 0.481 = 0.147)
With 3 unknowns and 2 equations to use, this is how many degrees of freedom I have (i.e., how many variables need to be specified)
What is 1?
These notations are used to describe moles and molar flowrate
What are n and n*?
(* refers to dot)
This is the difference between gauge and absolute pressure.
Gauge pressure is measuring the difference between atmospheric pressure and the pressure in a vessel (for example). Absolute pressure includes atmospheric pressure in the calculation.
This conversion factor will be used if you need to convert between weight (i.e., lb-mass) and force (i.e., lb-force)
What is gc?
A feed stream contains 127 kg of material. Two of the three outlet streams contain 1/8th, 1/4th of the input. These are the values of the three streams and and the ratio of the third outlet stream to the input.
What is 15.9, 31.8, and 79.4 kg and 62.5% (or 5/8ths)
When using equations for degree of freedom analysis, they need to be unaffected by other equations. In other words they need to be...
What is independent?
This letter represents mole fractions for a liquid stream
What is x?
This is what it means for a process to be at steady state.
What is not changing with time?
One pound mole of water is equal to this amount in pound mass
What is 18.02 pound mass?
These are the typical balances used to solve a Process Flow Diagram (PFD) problem.
What are overall and species balances?
One feed stream is used for a process with five components. There are two outlet streams, with the same components present in varying quantities. No other information is given. How many material balances can be used?
What is 6? Overall + five species balances. Although, only five balances are used. Generally, overall + four of the five species.
This letter represents a mole fraction in a vapor stream.
What is y?
For a three component outlet stream, where the overall molar flowrate and two of the three components are provided as mass fractions, how would you calculate the molar flowrate of the non-given species
Convert mass fractions to mole fractions, find non-given mole fraction, and multiply the mole fraction by the overall molar flowrate of the outlet stream.
These values (1.0, 1000, and 62.43) correspond to the following units for the density of water
What are g/cm3, kg/m3, and lb-mass/ft3?
(Page 46 of the textbook)
You are given mole fractions for a feed stream, but not given an overall flowrate. You also have information in the problem statement for two outlet streams. What do you do?
What is assume a basis?
If your DOF analysis is nonzero, this is what that tells you.
What is the system is under-constrained? In other words, you need more information or you're missing information from the problem statement to be used.
What is unitless? Specific gravity is a ratio of the density of the material you're investigating to the density of water.
You're given measurements of an Olympic swimming pool filled with a liquid that is not water. This is all of the information you would need to calculate the weight of the liquid.
What is the length and width of the pool, height of the liquid, and density or specific gravity of the liquid?