Module 5 : Electrochemistry
Lecture 21 : Review Of Thermodynamics
  21.13 
Pressure dependence of free energy.
At constant temperature, eq.(21.24) becomes
  
dG = VdP (21.45)
and the free energy at pressure P2, G 2 can be obtained through G 2 – G 1 = P1P2 VdP


For an ideal gas, V = nRT/P and (21.46)
G 2 –G 1 = G = P1P2 (nRT/P) dP
 
                  = nRT ln (P2 /P1 ) (21.47)
Free energy increases with increasing pressure, since volume is always positive.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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