What is the state of matter beyond the critical point?

Click For Summary
SUMMARY

The discussion focuses on the behavior of molecules transitioning from gas to liquid states beyond the critical point in a p-T phase diagram. It highlights that the concept of indistinguishable liquid and gas states suggests that molecular bonding may begin to occur during this transition. The conversation references the idea that phase boundaries are defined by discontinuities in thermodynamic quantities, emphasizing that the observation of latent heat is path dependent. Additionally, it mentions an article by Vadim V. Brazhkin and Kostya Trachenko in Physics Today, which explores how dynamical quantities can approximate the boundary between liquid and gas above the critical point.

PREREQUISITES
  • Understanding of p-T phase diagrams
  • Familiarity with thermodynamic quantities and phase transitions
  • Knowledge of latent heat concepts
  • Basic principles of molecular bonding
NEXT STEPS
  • Research the concept of "indistinguishable" states in thermodynamics
  • Study the article by Vadim V. Brazhkin and Kostya Trachenko in Physics Today
  • Explore advanced topics in phase transitions and critical phenomena
  • Learn about the role of dynamical quantities in thermodynamic systems
USEFUL FOR

Students and researchers in physics, particularly those studying thermodynamics, phase transitions, and critical phenomena, will benefit from this discussion.

oxivixo
Messages
4
Reaction score
0
Starting from a gas state and reaching the liquid state by getting around the critical point in a p-T phase diagram, what happens (qualitatively) to the molecules (or atoms)? Does a fraction of them start to form bonds?

This concept of "indistinguishable" liquid and gas is new to me.
 
Science news on Phys.org
http://books.google.com/books/about/Lectures_on_Phase_Transitions_and_the_Re.html?id=DdB1__nl7CYC gives the analogy that it's like two rooms, but the wall between them doesn't go all the way to the top. So whether you see "latent heat" associated with a phase transition is path dependent.

Typically, a phase boundary is defined by a discontinuity in some equilibrium thermodynamic quantity. It is by that sort of definition that whether one encounters a phase boundary between liquid and gas is path dependent.

There was however this interesting article in Physics Today about how dynamical quantities can provide an approximate boundary between liquid and gas above the critical point.

http://www.physicstoday.org/resource/1/phtoad/v65/i11/p68_s1?bypassSSO=1
Vadim V. Brazhkin and Kostya Trachenko
 
Last edited:

Similar threads

  • · Replies 12 ·
Replies
12
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 109 ·
4
Replies
109
Views
8K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
Replies
3
Views
2K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 14 ·
Replies
14
Views
2K
Replies
7
Views
2K