Helmholtz free energy: Difference between revisions

Revision as of 14:23, 20 February 2012

Helmholtz free energy

(Also called Helmholtz function, work function.) A thermodynamic function of state that, in a reversible isothermal process, increases with work done on the system.

In typical notation the Helmholtz free energy is

where F is the Helmholtz free energy (sometimes designated as A), U is the internal energy, T is temperature, and S is the entropy. By use of the first law of thermodynamics for reversible processes, the rate of change of the Helmholtz free energy is given by

where W is the work done by the system.
Compare Gibbs function.

INDEX
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
0
1
2
3
4
5
6
7
8
9

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-<div class="definition"><div class="short_definition">(<br/>''Also called'' Helmholtz function, work function.) A [[thermodynamic function  of state]] that, in a reversible [[isothermal process]], increases with [[work]] done on the system.</div><br/> <div class="paragraph">In typical notation the Helmholtz free energy is  <div class="display-formula"><blockquote>[[File:ams2001glos-He10.gif|link=|center|ams2001glos-He10]]</blockquote></div> where ''F'' is the Helmholtz free energy (sometimes designated as ''A''), ''U'' is the [[internal energy]], ''T''  is [[temperature]], and ''S'' is the [[entropy]]. By use of the [[first law of thermodynamics]] for reversible  processes, the rate of change of the Helmholtz free energy is given by  <div class="display-formula"><blockquote>[[File:ams2001glos-He11.gif|link=|center|ams2001glos-He11]]</blockquote></div> where ''W'' is the work done by the system. <br/>''Compare'' [[Gibbs function]].</div><br/> </div>
+<div class="definition"><div class="short_definition">(''Also called'' Helmholtz function, work function.) A [[thermodynamic function  of state]] that, in a reversible [[isothermal process]], increases with [[work]] done on the system.</div><br/> <div class="paragraph">In typical notation the Helmholtz free energy is  <div class="display-formula"><blockquote>[[File:ams2001glos-He10.gif|link=|center|ams2001glos-He10]]</blockquote></div> where ''F'' is the Helmholtz free energy (sometimes designated as ''A''), ''U'' is the [[internal energy]], ''T''  is [[temperature]], and ''S'' is the [[entropy]]. By use of the [[first law of thermodynamics]] for reversible  processes, the rate of change of the Helmholtz free energy is given by  <div class="display-formula"><blockquote>[[File:ams2001glos-He11.gif|link=|center|ams2001glos-He11]]</blockquote></div> where ''W'' is the work done by the system. <br/>''Compare'' [[Gibbs function]].</div><br/> </div>
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