Constant thermodynamic potentials examples

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The discussion focuses on identifying real-world processes where internal energy, enthalpy, Gibbs free energy, and Helmholtz free energy remain constant. Participants emphasize the importance of understanding the physical interpretations of thermodynamic equations rather than just seeking examples. The Joulle-Thompson effect is mentioned as a potential example for constant enthalpy. There is a consensus that providing real-world examples aids in grasping thermodynamic concepts better. Overall, the thread encourages active engagement and personal effort in learning thermodynamics.
dperkovic
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Homework Statement



Specify at least two ( physical or chemical), real world, processes for each of this cases:

a) Internal energy is constant
b) Entalpy is constant
c) Gibbs free energy is constant
d) Helmholtz free energy is constant

Homework Equations



a) dU = TdS - pDV = 0
b) dH = TdS + VdP = 0
c) dG = dH - tdS = 0, or dG =vDp -SdT = 0 ?
d) dF = -(pdV + SdT ) = 0

The Attempt at a Solution



b) Joulle-Thompson effekt

...and this is all what I found...Thanks for any help !
 
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It's not going to help you learn if people just provide the examples for you, so let's try this tack: what's the physical interpretation of dS=0? How about dP=0, and the others? Can you brainstorm some cases where these restrictions apply? For example, which state variables are constant when an exposed solid melts to form a liquid?
 
Mapes said:
It's not going to help you learn if people just provide the examples for you, so let's try this tack: what's the physical interpretation of dS=0? How about dP=0, and the others? Can you brainstorm some cases where these restrictions apply? For example, which state variables are constant when an exposed solid melts to form a liquid?

Maybe it is true, but I think that knowing real world examples help me to better understand thermodynamics. Than, I can compare "mathematics" with real world.
 
dperkovic said:
Maybe it is true, but I think that knowing real world examples help me to better understand thermodynamics. Than, I can compare "mathematics" with real world.
This stand for constant gibbs, am I right ?
 
dperkovic said:
Maybe it is true, but I think that knowing real world examples help me to better understand thermodynamics. Than, I can compare "mathematics" with real world.

Sorry, we don't provide answers to homework-type questions. If you show your own effort, however, you'll likely get helpful comments.
 
Mapes said:
Sorry, we don't provide answers to homework-type questions. If you show your own effort, however, you'll likely get helpful comments.

I'll try, thank you anyway
 

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