Cannabis Ruderalis October 12, 2016 thcscience_admin You do not have permission to edit this page, for the following reason: You can view and copy the source of this page:==Branches of thermodynamics== The study of thermodynamical systems has developed into several related branches, each using a different fundamental model as a theoretical or experimental basis, or applying the principles to varying types of systems. ===Classical thermodynamics=== Classical thermodynamics is the description of the states of thermodynamic systems at near-equilibrium, that uses macroscopic, measurable properties. It is used to model exchanges of energy, work and heat based on the [[laws of thermodynamics]]. The qualifier ''classical'' reflects the fact that it represents the first level of understanding of the subject as it developed in the 19th century and describes the changes of a system in terms of macroscopic empirical (large scale, and measurable) parameters. A microscopic interpretation of these concepts was later provided by the development of ''statistical mechanics''. ===Statistical mechanics=== [[Statistical mechanics]], also known as statistical thermodynamics, emerged with the development of atomic and molecular theories in the late 19th century and early 20th century, and supplemented classical thermodynamics with an interpretation of the microscopic interactions between individual particles or quantum-mechanical states. This field relates the microscopic properties of individual atoms and molecules to the macroscopic, bulk properties of materials that can be observed on the human scale, thereby explaining classical thermodynamics as a natural result of statistics, classical mechanics, and [[Quantum mechanics|quantum theory]] at the microscopic level. ===Chemical thermodynamics=== [[Chemical thermodynamics]] is the study of the interrelation of [[energy]] with [[chemical reactions]] or with a physical change of [[thermodynamic state|state]] within the confines of the [[laws of thermodynamics]]. The primary objective of chemical thermodynamics is determining the spontaneity of a given transformation.<ref>{{cite book |last1=Klotz |first1=Irving |title=Chemical Thermodynamics: Basic Theory and Methods |date=2008 |publisher=John Wiley & Sons, Inc. |location=Hoboken, New Jersey |page = 4 |isbn=978-0-471-78015-1}}</ref> ===Equilibrium thermodynamics=== [[Equilibrium thermodynamics]] is the study of transfers of matter and energy in systems or bodies that, by agencies in their surroundings, can be driven from one state of thermodynamic equilibrium to another. The term 'thermodynamic equilibrium' indicates a state of balance, in which all macroscopic flows are zero; in the case of the simplest systems or bodies, their intensive properties are homogeneous, and their pressures are perpendicular to their boundaries. In an equilibrium state there are no unbalanced potentials, or driving forces, between macroscopically distinct parts of the system. A central aim in equilibrium thermodynamics is: given a system in a well-defined initial equilibrium state, and given its surroundings, and given its constitutive walls, to calculate what will be the final equilibrium state of the system after a specified thermodynamic operation has changed its walls or surroundings. ===Non-equilibrium thermodynamics=== [[Non-equilibrium thermodynamics]] is a branch of thermodynamics that deals with systems that are not in [[thermodynamic equilibrium]]. Most systems found in nature are not in thermodynamic equilibrium because they are not in stationary states, and are continuously and discontinuously subject to flux of matter and energy to and from other systems. The thermodynamic study of non-equilibrium systems requires more general concepts than are dealt with by equilibrium thermodynamics.<ref>{{Cite book|url=|title= Thermodynamics of Complex Systems: Principles and applications. |last= Pokrovskii |first=Vladimir|language=English | publisher= IOP Publishing, Bristol, UK.|year=2020|isbn=|pages=|bibcode= 2020tcsp.book.....P }}</ref> Many natural systems still today remain beyond the scope of currently known macroscopic thermodynamic methods. Return to Thermodynamics.