Internal and thermal energy vs Temp?

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SUMMARY

The discussion centers on the concepts of internal energy and thermal energy in relation to temperature, specifically in the context of adiabatic expansion of an ideal gas, such as oxygen. It is established that during adiabatic free expansion, the temperature and internal energy of the gas remain unchanged, as no work is done and no heat is exchanged. The concept of latent heat is also touched upon, particularly regarding the differences in internal and thermal energy between ice and water at 0°C. The "Joule free expansion experiment" is referenced as a key example for understanding these principles.

PREREQUISITES
  • Understanding of thermodynamics principles, particularly the first law of thermodynamics.
  • Familiarity with ideal gas laws and behavior.
  • Knowledge of latent heat and phase changes in substances.
  • Basic mathematical skills for applying thermodynamic equations.
NEXT STEPS
  • Research the "Joule free expansion experiment" to understand its implications on internal energy.
  • Study the first law of thermodynamics and its applications in adiabatic processes.
  • Explore the concept of latent heat and its effects on phase transitions, particularly between ice and water.
  • Learn about the properties of ideal gases and how they behave under different thermodynamic conditions.
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Students of physics, educators teaching thermodynamics, and anyone seeking to deepen their understanding of energy concepts in thermodynamic systems.

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Internal and thermal energy vs Temp?

Hello I am a layman who is seriously trying to grasp the concepts and principles of physics to understand the workings of the world.
I have seen the equations for deriving Internal Energy and Thermal Energy but lack the math to apply them or be sure if I have got the concepts.
A couple of examples would be very helpful as reading hasnt brought certainty

SO if there is a volume of intermolecularly positive gas say, Oxygen ,that has been allowed to reach environmental temp [under the inversion temp] and it is then adiabatically expanded into a vacuum :
1 the temp would drop. COrrect??

2 What would be the Internal energy evaluation of the two states , compressed vs expanded? Would the internal energy level also drop or would the two states be equivalent?

3 Same question regarding the Thermal energy evaluation.

As there would be no work done and no system loss to the environment , logically I would assume the two states would be equivalent but am unsure of this.

Also regarding Ice and H2O at 0 C. Would the difference in latent heat energy show up as a lower internal/thermal energy level for the ice?

I know these questions may be elementary but they have plagued me for some time and any help would be very appreciated. Thanks
 
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If the gas is ideal, there is no change in the temperature after an adiabatic free expansion. The internal energy stays the same as well (no work done, no heat exchanged...).
But I would not say that the states are equivalent, although I'm not sure what you mean by "equivalent".

I do not know what you mean by "intermolecularly positive gas" either, but sounds like you're
thinking of the "Joule free expansion experiment". Plenty of information on the web, and in textbooks of course.
 

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