1. Definitions and basics
1.1 System and state in thermodynamics: definitions and qualifications
A system is any set of material elements, bounded by a fictitious boundary generally referred to as the envelope. The envelope of a system is of zero thickness, so that the properties of the material on either side of the boundary are exactly the same. It should never be confused with the actual wall of a container. The region of space outside the chosen boundary is called the external medium.
The set {system & external environment} is called the universe. So, if the system under study is the entire universe, there is no external environment.
There are only three modes of energy transfer between a system and the external environment that can lead to a variation...
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Unit operations. Chemical reaction engineering
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Definitions and basics
Calculating a partial molar quantity from a total molar quantity
Bibliography
As this article deals with fundamental concepts, the authors did not deem it necessary to include references in the body of the article. However, the authors have included a list of books they recommend for more in-depth reading of the concepts presented throughout the article:
general works on chemical thermodynamics [1] to [7];
books describing...
Directory
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Center for Process Thermodynamics (Mines Paristech, Fontainebleau, France): https://www.ctp.minesparis.psl.eu/
LRGP thermodynamics and energy team (CNRS, Université de Lorraine, Nancy, France):
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