Relation between chemical potential and S,V,T,P

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SUMMARY

The discussion focuses on the relationship between chemical potential and thermodynamic variables such as entropy (S), volume (V), temperature (T), and pressure (P). The chemical potential (μ) is defined as the Gibbs potential per particle, expressed mathematically as μ = G/N. The derivation of the Gibbs-Duhem equation, dμ = -SdT + VdP, illustrates that in a simple system, the intensive parameters T, P, and μ are interdependent. This equation is particularly significant in the study of multicomponent systems, where it aids in understanding vapor-liquid equilibrium and chemical reaction equilibrium.

PREREQUISITES
  • Understanding of Gibbs potential and its formulation
  • Familiarity with thermodynamic variables: entropy (S), volume (V), temperature (T), and pressure (P)
  • Knowledge of the Gibbs-Duhem equation and its implications
  • Concept of chemical potential in single and multicomponent systems
NEXT STEPS
  • Study the Gibbs-Duhem equation in detail to understand its applications in thermodynamics
  • Explore the concept of chemical potential in multicomponent mixtures and its role in phase equilibria
  • Learn about vapor-liquid equilibrium and its significance in chemical engineering
  • Investigate the relationship between intensive and extensive properties in thermodynamic systems
USEFUL FOR

This discussion is beneficial for students and professionals in thermodynamics, particularly those studying chemical engineering, physical chemistry, and anyone interested in the principles of phase equilibria and chemical reactions.

Pushoam
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Homework Statement



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Homework Equations

The Attempt at a Solution

Chemical potential is defined as ## \mu = Gibbs potential per particle ##.

So, is the system consists of N particles, ##\mu = \frac { G } {N } ##.

Now, dG = VdP – SdT

## \frac {dG } { N } = \frac { VdP } { N } - \frac { SdT } { N}##

So, ## d{\mu} = -sdT + v dP##.

Hence the correct option is (a).

Is this correct?

I didn't get the physical significane of this question.
How does the knowledge of above eqn help us in our study of thermodynamics?
 

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Your answer is correct. This is the Gibbs-Duhem equation which tells us that for a simple system, the intensive parameters (T, P, μ) are not independent. Knowledge of 2 is enough to determine the 3rd up to an integration constant. Have a look at Wiki page too:
https://en.wikipedia.org/wiki/Gibbs–Duhem_equation
 
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Pushoam said:
I didn't get the physical significane of this question.
How does the knowledge of above eqn help us in our study of thermodynamics?
For the single component system you are considering, the chemical potential doesn't make much sense. But its value comes into play "big time" when you are considering multicomponent mixtures. It is used in describing multicomponent vapor-liquid equilibrium, multiphase equilibrium, and chemical reaction equilibrium. Be patient, and you will learn about this soon.
 
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Thanks for the reply.
The following eqn uses extensive parameters.
Pushoam said:
dG = VdP – SdT
.
We have derived the following eqn from the above eqn. One of the significance of the following eqn is: it consists of only intensive parameters.
Pushoam said:
## d{\mu} = -sdT + v dP##
 

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