An extremely Novice energy question

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Discussion Overview

The discussion revolves around the relationship between mass and energy as described by the equation e=mc², particularly in the context of food consumption and the energy potential of different atomic states before and after consumption. Participants explore the concept of mass deficit and its implications in both chemical and nuclear reactions.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant questions the energy potential of food before and after consumption, noting that the mass remains equal in both states.
  • Another participant corrects this by stating that the mass is actually slightly less in the less energetic state, referring to the concept of "mass deficit," particularly in the context of chemical reactions.
  • A subsequent participant inquires about the measurement of this effect, specifically whether it has been observed.
  • One participant confirms that mass deficit has been measured in nuclear reactions but suggests that it is too small to measure in chemical reactions.
  • Another participant elaborates that high-resolution mass spectrometry techniques can measure very small mass differences and mentions a proposed experiment to measure the "electronic mass defect" in chemical reactions, although they express doubt about the adequacy of current technology for this task.

Areas of Agreement / Disagreement

Participants express differing views on the measurability of mass deficit in chemical reactions, with some asserting it is too small to detect while others suggest advanced techniques may be capable of measuring it.

Contextual Notes

The discussion highlights limitations regarding the measurement of mass differences in chemical versus nuclear reactions and the dependence on technological capabilities for detecting small mass deficits.

khz
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I'm sure this has been thoroughly answered, so I'm sorry.
So, you have e=mc2, yet when you have food (or anything) before consumption and after consumption, the mass of both atomic states is equal, yet the form of the former state (before consumption) gives the mass more energy potential than the latter state.
?
 
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khz said:
the mass of both atomic states is equal
Actually, the mass is slightly less in the less energetic state. This is called "mass deficit". The difference is very small for chemical reactions.
 
oh wow thanks. Are you aware if this effect has been measured?
 
Yes, for nuclear reactions. To my knowledge it is too small to measure for chemical reactions.
 
DaleSpam said:
Yes, for nuclear reactions. To my knowledge it is too small to measure for chemical reactions.

Actually, very high resolution Fourier transform ion cyclotron resonance (FTICR) mass spectrometers can already reproducibly measure mass differences that are significantly smaller than the electron mass. I have seen at least one experiment proposed to measure the "electronic mass defect" associated with a chemical reaction, however I think the technology was still not quite adequate to the task.
 

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