Does the Speed of Electrons Around Atomic Nuclei Affect Temperature?

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Discussion Overview

The discussion revolves around the relationship between the speed of electrons around atomic nuclei and temperature, exploring concepts from relativity, thermal energy, and the nature of temperature itself. Participants examine how these ideas relate to classical and quantum mechanics, as well as the implications for states of matter like plasma.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant questions how relativity influences the speed of electrons and thermal energy vibrations, suggesting that both electron speed around nuclei and interatomic motion contribute to kinetic energy and thus temperature.
  • Another participant asserts that temperature is defined as the derivative of energy with respect to entropy, arguing that the relationship between speed and temperature is not applicable to electrons in atoms, which do not behave like classical particles.
  • A different participant echoes the claim that temperature is not directly related to energy per unit mass, emphasizing that temperature is a state quantity rather than a mass quantity.
  • One participant challenges the idea that average particle speed correlates with temperature, using the example of different gases at the same temperature having different average speeds, and suggests that the discussion conflates temperature with heat.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between electron speed and temperature, with no consensus reached. Some argue that speed is relevant to temperature, while others contest this notion, leading to a debate over the definitions and implications of temperature in different contexts.

Contextual Notes

Participants reference classical and quantum mechanics, and the discussion includes unresolved assumptions about the definitions of temperature and energy. The implications of these definitions on the understanding of states of matter, such as plasma, are also noted but not fully explored.

resolvent
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Please, could someone here teach me, in a no-pun-intended crash course :smile:,
of how relativity plays into the speed of electrons flying around an atomic nucleus
as well as thermal energy vibrations.

Ok - I know it's wrong to think like they did in the 19h century, making the analogy of electrons around atomic nuclei to planets revolving around a sun.

Nevertheless, (average) particle speed is what temperature is.

Also, I never understood: does the "speed" of electrons "flying around atomic nuclei" have anything to do with temperature? At sufficiently high temperatures, depending upon the element or compound, electrons do get stripped away from atomic nuclei. So, I assume a plasma is some sort of "soup" of electrons and atomic nuclei. Hence, it does not seem to me that there is any difference between temperature associated with electrons "flying around a nucleus" versus interatomic Brownian motion, since both contribute to the kinetic energy of the ensemble.

Finally, the Nova program on the race for absolute zero asked if there is an "absolute hot".
Wouldn't that be fixed by the "speed of light" of these electrons and nuclei?
 
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Temperature has nothing to do with the amount of energy --- it's the derivative of energy with respect to entropy. Indeed, the hottest possible temperature (in the sense that if you put anything in contact with it, the net energy flow will be outwards) is minus zero.

The usual "speed=heat" is only true for a classical gas. Electrons around atoms are neither classical, nor a gas.
 
genneth said:
Temperature has nothing to do with the amount of energy --- it's the derivative of energy with respect to entropy. Indeed, the hottest possible temperature (in the sense that if you put anything in contact with it, the net energy flow will be outwards) is minus zero.

I did not mean to make it sound like I believed that temperature is a "mass" quantity,
that depends upon the total mass of a system. Of course, temp is a state quantity.

Nevertheless, I don't see how temp has nothing to do with the amount of energy per unit mass. I know you did not say "per unit mass", but I infer you would have added that anyway.
 
resolvent said:
Nevertheless, (average) particle speed is what temperature is.

Absolutely untrue. Even in the case of gases, where this makes the most sense, it's not true. The average particle speed of a tank of hydrogen at 300K is not the same as the average particle speed of a tank of xenon at the same temperature.

resolvent said:
Nevertheless, I don't see how temp has nothing to do with the amount of energy per unit mass. I know you did not say "per unit mass", but I infer you would have added that anyway.

What you are describing is closer to heat than temperature.
 

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