List of thermodynamic properties

Main article: Intensive and extensive properties

Within thermodynamics, a physical property is any property that is measurable, and whose value describes a state of a physical system. Some constants, such as the ideal gas constant, R, do not describe the state of a system, and so are not properties. On the other hand, some constants, such as K_f (the freezing point depression constant, or cryoscopic constant), depend on the identity of a substance, and so may be considered to describe the state of a system, and so may be considered physical properties.

"Specific" properties are expressed on a per mass basis. If the units were changed from per mass to, for example, per mole, the property would remain as it was (i.e., intensive or extensive).

Regarding Work and Heat

Work and heat are not thermodynamic properties, but rather process quantities: flows of energy across a system boundary. Systems do not contain work, but can perform work, and likewise, in formal thermodynamics, systems do not contain heat, but can transfer heat. Informally, however, a difference in the energy of a system that occurs solely because of a difference in its temperature is commonly called heat, and the energy that flows across a boundary as a result of a temperature difference is "heat".

Altitude (or elevation) is usually not a thermodynamic property. Altitude can help specify the location of a system, but that does not describe the state of the system. An exception would be if the effect of gravity needed to be considered in order to describe a state, in which case altitude could indeed be a thermodynamic property.

Thermodynamic properties and their characteristics
Property	Symbol	Units	Extensive?	Intensive?	Conjugate	Potential?
Activity	$a$	–		Y
Chemical potential	$\mu _{i}$	kJ/mol		Y	Particle number $N_{i}$
Compressibility (adiabatic)	$\beta _{S}$ , $\kappa$	Pa⁻¹		Y
Compressibility (isothermal)	$\beta _{T}$ , $\kappa$	Pa⁻¹		Y
Cryoscopic constant^[1]	$K_{f}$	K·kg/mol
Density	$\rho$	kg/m³		Y
Ebullioscopic constant	$K_{b}$
Enthalpy	$H$	J	Y			Y
Specific enthalpy	$h$	J/kg		Y
Entropy	$S$	J/K	Y		Temperature $T$	Y (entropic)
Specific entropy	$s$	J/(kg K)		Y
Fugacity	$f$	N/m²		Y
Gibbs free energy	$G$	J	Y			Y
Specific Gibbs free entropy	$g$	J/(kg K)		Y
Gibbs free entropy	$\Xi$	J/K	Y			Y (entropic)
Grand / Landau potential	$\Omega$	J	Y			Y
Heat capacity (constant pressure)	$C_{p}$	J/K	Y
Specific heat capacity (constant pressure)	$c_{p}$	J/(kg·K)		Y
Heat capacity (constant volume)	$C_{v}$	J/K	Y
Specific heat capacity (constant volume)	$c_{v}$	J/(kg·K)		Y
Helmholtz free energy	$A$ , $F$	J	Y			Y
Helmholtz free entropy	$\Phi$	J/K	Y			Y (entropic)
Internal energy	$U$	J	Y			Y
Specific internal energy	$u$	J/kg		Y
Internal pressure	$\pi _{T}$	Pa		Y
Mass	$m$	kg	Y
Particle number	$N_{i}$	–	Y		Chemical potential $\mu _{i}$
Pressure	$p$	Pa		Y	Volume $V$
Temperature	$T$	K		Y	Entropy $S$
Thermal conductivity	$k$	W/(m·K)		Y
Thermal diffusivity	$\alpha$	m²/s		Y
Thermal expansion (linear)	$\alpha _{L}$	K⁻¹		Y
Thermal expansion (area)	$\alpha _{A}$	K⁻¹		Y
Thermal expansion (volumetric)	$\alpha _{V}$	K⁻¹		Y
Vapor quality^[2]	$\chi$	–		Y
Volume	$V$	m³	Y		Pressure $P$
Specific volume	$v$	m³/kg		Y

References

↑ Aylward, Gordon; Findlay, Tristan (2002), SI Chemical Data 5th ed. (5 ed.), Sweden: John Wiley & Sons, p. 202, ISBN 0-470-80044-5
↑ Cengel, Yunus A.; Boles, Michael A. (2002). Thermodynamics: an engineering approach. Boston: McGraw-Hill. p. 79. ISBN 0-07-121688-X.

This article is issued from Wikipedia - version of the 9/17/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.

List of thermodynamic properties

See also

References