Thermodynamic State


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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Thermodynamic State

 

the state in which a thermodynamic system exists. Thermodynamic states are characterized by a set of macroscopic properties, which determine the internal properties of a system in that state and the interaction of the system with external bodies. These properties include temperature, pressure, volume, electric polarization, and magnetization.

Among the thermodynamic state properties there exists a specific number of independent variables, equal to the number of thermodynamic degrees of freedom of the system; the remaining variables can be expressed in terms of the independent variables. Thus, in the equation of state for an ideal gas, pV = RT, two variables—for example, temperature T and volume V —are independent, and the third, the pressure of the gas p, can be found from T and V (R is the gas constant). In thermodynamics, a distinction is made between equilibrium states and nonequilibrium states; the latter are studied in the thermodynamics of irreversible processes.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Figure 2 shows the schematic of the ARS, with all of the control volumes and the eighteen points of thermodynamic state for the modeling and simulation in the steady state regime.
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