|
|
The
Gibbs Function, G, is a thermodynamic parameter defined as:
G
= H - TS, where
H is the enthalpy, T the Kelvin temperature, and S the entropy of the system.
G is often called the Gibbs free energy.
In
an arbitrary process, the change in the Gibbs function is given by:
dG
= dH - TdS - SdT. Expanding H to get: dH = dU + pdV + vdP, and recognizing
that the First law states that
dU
+ pdV = TdS, gives:
dG = VdP - SdT.
From
this relationship two identifications can be made:
(dG/dP)T = V,
and (dG/dT)P
= -S |
|
|
|
|
|
|
|
