Internal and thermal energy vs Temp?

AI Thread Summary
Internal energy and thermal energy are distinct concepts in thermodynamics, with temperature being a measure of the average kinetic energy of particles. In an adiabatic free expansion of an ideal gas, the temperature remains constant, and therefore, the internal energy does not change since no work is done and no heat is exchanged. The states of the gas before and after expansion are not equivalent in terms of their physical arrangement, although their internal energy remains the same. Regarding the phase change from ice to water at 0°C, the latent heat energy indicates that ice has a lower thermal energy compared to liquid water, reflecting the energy required for the phase transition. Understanding these principles is crucial for grasping the behavior of gases and phase changes in thermodynamics.
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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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