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I did my Thermo course already. Why do I need your Stat Thermo?

phe-nomé-nólo-gy,n...2.Scientific description of actual phenomena with avoidance of full interpretation, explanation, and evaluation

Webster's Collegiate Dictionary, 5th edition.

**Phenomenological Thermodynamics:**-
- Developed
*before*atomistics - We know that if A is colder than B, heat will flow from B to A.
- We know that there is such thing as energy that conserves
- We know that there is such thing as entropy that increases

- Developed

**Problems with Phenomenological Thermodynamics:**-
- We know
*how*, but do not know*why*.- Why do liquids evaporate at heating but never at cooling?
- Why do all gases behave similarly?
- Can the temperature be negative?
- What is this thing entropy, by the way?

- We need all the constants and parameters from the experiments (that is what phenomenology means, by the way). We have no clue about their possible values!
- We have no clue what thermodynamic properties will the
systems, build with
*given*molecules have--not very good for*materials science*! We can build a refrigerator, but we cannot design a proper fluid for it--we can only choose from the ones we know!

- We know

© 1997

Wed Sep 3 22:38:51 EDT 1997