Work: Difference between revisions
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{{MitoPedia | {{MitoPedia | ||
|abbr=''W'' | |abbr=''W'' [J] | ||
|description='''Work''' [J] is a specific form of [[energy]], called [[exergy]], performed by a closed or open system on its surroundings (the environment). This is the definition of ''external'' work, which is zero in [[isolated system]]s. Mechanical work is force [N] times path length [m]. The internal-energy change, d''U'', is due to exchange of work and heat, and work is the internal energy change minus heat, | |description='''Work''' [J] is a specific form of [[energy]], called [[exergy]], performed by a closed or open system on its surroundings (the environment). This is the definition of ''external'' work, which is zero in [[isolated system]]s. Mechanical work is force [N] times path length [m]. The internal-energy change, d''U'', is due to exchange of work and heat, and work is the internal energy change minus heat, | ||
Β d''W'' = d''U'' - d''Q'' | Β d''W'' = d''U'' - d''Q'' |
Revision as of 18:54, 28 December 2018
Description
Work [J] is a specific form of energy, called exergy, performed by a closed or open system on its surroundings (the environment). This is the definition of external work, which is zero in isolated systems. Mechanical work is force [N] times path length [m]. The internal-energy change, dU, is due to exchange of work and heat, and work is the internal energy change minus heat,
dW = dU - dQ
Abbreviation: W [J]
Reference: Gnaiger (1993) Pure Appl Chem
Communicated by Gnaiger E 2018-10-20
Pressure-volume work
- Pressure-volume work, dVW, at constant pressure, is the gas pressure, p [Pa = JΒ·m-3], times volume, V [m3],
dVW = -pΒ·dV [J]
- The available work, deW, is distinguished from external total work as [1]
deW = dW - dVW
- The enthalpy change, dH, at constant pressure, is defined as internal-energy change minus pressure-volume work,
dH = dU - dVW
References
- Gnaiger E (1993) Nonequilibrium thermodynamics of energy transformations. Pure Appl Chem 65:1983-2002. - Β»Bioblast linkΒ«
MitoPedia concepts:
Ergodynamics