BasicPrinciplesOfC&SThermodynamicsByTWLeland -...

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Basic Principles of Classical and Statistical Thermodynamics
By
Thomas W. Leland, Jr.
(*)
Preparation and editorial by
G.A. Mansoori
Department of Chemical Engineering, University of Illinois at Chicago
810 S. Clinton Street, Chicago, IL 60607-7000, <[email protected]>
(*) Thomas William Leland, Jr. (1924-1986), was born in Chicago, Illinois, earned the degree of bachelor of
science in 1947 from Texas A&M College. received the degree of master of science in 1949 from the University
of Michigan, and was awarded the degree of doctor of philosophy in 1954 under Professor John McKetta at the
University of Texas at Austin . Professor Leland taught at the University of Arkansas and the Rice
University. During the course of his research, Professor Leland published in excess of seventy technical
publications on applications of corresponding states theory to fluid mixtures, thermodynamics of solutions,
and fluid mixtures.
In the most general sense thermodynamics is the study of energy -- its transformations and
its relationship to the properties of matter. In its engineering applications thermodynamics
has two major objectives. One of these is to describe the properties of matter when it exists
in what is called an equilibrium state, a condition in which its properties show no tendency
to change. The other objective is to describe processes in which the properties of matter
undergo changes and to relate these changes to the energy transfers in the form of heat and
work which accompany them. These objectives are closely related and a text such as this,
which emphasizes primarily the description of equilibrium properties, must include as well a
discussion of the basic principles involved in accomplishing these two objectives.
Thermodynamics is unique among scientific disciplines in that no other branch of
science deals with subjects which are as commonplace or as familiar. Concepts such as
"heat", "work", "energy", and "properties" are all terms in everyone's basic vocabulary.
Thermodynamic laws which govern them originate from very ordinary experiences in our
daily lives. One might think that this familiarity would simplify the understanding and
application of thermodynamics. Unfortunately, quite the opposite is true. In order to

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accomplish these objectives, one must almost entirely forget a life-long acquaintance with
the terms of thermodynamics and redefine them in a very scientific and analytical manner.
We will begin with a discussion of the various properties of matter with which we will be
concerned.
1 Thermodynamic and Non-Thermodynamic Properties
A property of matter is any characteristic which can distinguish a given quantity of
a matter from another. These distinguishing characteristics can be classified in several
different ways, but for the purposes of this text it is convenient to divide them into what
may be called thermodynamic and non-thermodynamic properties.