Thermodynamics A214 Chapter 3 Summary Notes

Properties of Pure substances
Chapter 3 :




pure substance - A substance that has a fixed chemical

composition throughout
Could be mixture of phases
a as
long as
-

,




everything in the mixture vaporise at the

same temperature
phases :


solid

Liquid
} how A volume with heat



Gas } High Dudeme with heat


[ ideal but NEVER
Can sometimes use
gas equations ,




with liquids or solids or
liquid -
vapour mixtures


Phase
changes of Pure
Liquids :


constant pressure
in °
-


;


→↳
too ? saturation
,;• -•j temperature Kemp of phase changed
→ . - -
. .
- - - - - - - -
-




-
!
•
50
I



>

✓



① Compressed Liquid -
100% liquid
(sub cooled liquid)
② saturated Liquid -
100% liquid
-
About to vaporise

, ③ saturated Liquid - - Both saturated liquid and
vapour of
Vapour Mixture saturation temperature

④ saturated Vapour - 100%
gas
On the of condensation
verge
-




⑤ superheated Vapour - 100%
gas
- Above saturation temperature

pressures :
Changing
-
saturation temperature changes with pressure


P=22MFa
critical point
of 370


i.




-

saturation pressure
- There is
any per saturation temperature
and vice versa .




←
i. .
If we have the set temp .
→ can
get set pressure
.




it For saturated
liquid , mixture $ vapour L② ③ ④) .
.




The amount of Cheat)
Latent Heat -

energy
absorbed
during a
phase change