Chapter 3: Monday March 18 2024-Notes Flashcards
A quantity of matter that is uniform throughout in both chemical composition and physical structure
Phase
One that is uniformed in chemical composition only. Can have more than 1 phase within it.
Pure Substance
Is Water with ice cubes in it a pure substance?
Yes
Is water and oil considered to be a pure substance?
No
Is alcohol and water a pure substance?
No because it’s has a different chemical composition. Even though they mix together.
Guide to describe a system using independent properties
State Principle
Only two independent properties are needed to completely describe the system
Simple Compressible system
Subset of pure substance
Simple compressible system
What is the only mode of work done that’s through a quasi equilibrium pressure-volume work.
Simple compressible system
The analyses of internal energy ‘V’ and the product of pressure + volume appears a lot
Or
Heat constant of the system
Enthalpy (H)
H= V+PV
Is what equation?
Enthalpy
What’s Specific Enthalpy’s Equation?
H/Mass = h = u+pv
Does p-v and T-v diagrams have the same shape?
yes
Is P-v or T-v diagram easier to look at?
T-v is easier to look at
What is a bar unit
It means the atmosphere pressure
Having a closed system means what?
There is no mass change or change to friction force
p is what unit?
Pressure
Starting at 20 degrees C and slowly increasing it’s temperature to 100 degrees C, is which process?
A. L-f
B. F-g
C. G-s
A
The temperature is at 100 degrees C and is still heating up which process is this?
A. L-f
B. F-g
C. G-s
B
At this point the substances is in a vapor state but is still increasing it’s temperature which process is this?
A. L-f
B. F-g
C. G-s
C
When going from l-f what is the substances matter state?
100% liquid water
When going from f-g what state of matter is it?
Vapor and liquid water
When going from g-s what state of matter is it?
100% vapor
A line of constant pressure is called what
Isobar
In a T-v diagram: Temp starts at a standard value and goes up and v goes up too til 100 degrees
L-f
In a T-v diagram: Temp remains constant, but v goes up creating a phase change
F-g
In a T-v diagram: Temp goes up but starting above 100 degrees and v goes up as well
G-s
What does this symbol mean:
Pc
Critical pressure
In either a T-v or a P-v diagram: First region to the left of the critical pressure constants what
Always liquid
In either a T-v or a P-v diagram: Underneath the curve and the critical pressure is the second region that contains
A mixture of liquid and vapor
Also know as the two phase region
In either a T-v or a P-v diagram: The third region is to the right of the critical pressure containing
Only vapor
What is the curve in the phase change diagram?
Saturation curve
In a P-v diagram: starting at a standard atmospheric value and pressure drops to 2300 Pa but the volume increases
A. L-f
B. F-g
C. G-s
L-f
In a P-v diagram: the increase in volume but your not gaining or losing pressure.
A. L-f
B. F-g
C. G-s
F-g
In a P-v diagram: Where your at 2300 Pa and you start dropping pressure again and slowly gaining volume.
A. L-f
B. F-g
C. G-s
G-s
Does P-valley diagrams deal with a change in temperatures?
Yes, but no. With a single line there is no change in the temperature, but if you add another line there could be another temperature that also doesn’t change.
What does f mean in T-v and P-v diagrams?
Saturated liquid state
Means that at this point the system contains the max amount of liquid that it can have.
What does g mean in both a T-v and a P-v diagram?
Saturated vapor state
Means that this is the state where all of the liquid has converted to vapor
L-f means what in a T-v or a P-v diagram?
Liquid state
F-g means what in T-v and P-v diagrams?
Two phase dome
G-s means what in a T-v and a P-v diagram?
Vapor state
