Proton vs Neutron: Mass Comparison

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Discussion Overview

The discussion revolves around the mass comparison between protons and neutrons, exploring their respective masses, stability, and implications in nuclear processes. Participants engage in technical reasoning and clarification regarding particle physics concepts.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants assert that a neutron is more massive than a proton, with one noting a mass difference of about 0.2% and an energy difference of 1.29 MeV.
  • One participant mentions that free neutrons are unstable and decay with a lifetime of approximately 12 minutes, expressing surprise at the mass difference being greater than expected.
  • Another participant challenges the understanding of mass, stating that the mass of a proton is significantly greater than that of an electron, suggesting a misunderstanding in the comparison of masses.
  • A question is raised regarding the energy dynamics when a proton turns into a neutron during nuclear fusion, specifically where the extra energy comes from.
  • One participant discusses the concept of bonding energy, explaining that when particles bond, the resulting particle can have a lower mass than the sum of its constituents.
  • There are expressions of confusion and disagreement regarding the relationship between protons, neutrons, and electrons, with some participants questioning the validity of certain claims made in the discussion.

Areas of Agreement / Disagreement

Participants express disagreement on several points, particularly regarding the mass comparison and the implications of particle transformations. There is no consensus on the interpretations of the mass differences or the energy dynamics involved.

Contextual Notes

Some statements rely on specific definitions and assumptions about particle masses and decay processes, which may not be universally accepted or understood among all participants.

colinr
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isn't a neutron more massive thatn a proton?
 
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It is. Free neutrons are even unstable and decay with a lifetime of something like 12min. To my big surprise, when I looked it up, the mass-difference was much more than I expected: 2.5 times the mass of an electron (I expected not much more than the electron mass).
 
The neutron is about 0.2% more massive than a proton, which translates to an energy difference of 1.29 MeV. I believe that the added mass of the electron plus the proton equals very close to the mass of the neutron.
 
Atheist said:
It is. Free neutrons are even unstable and decay with a lifetime of something like 12min. To my big surprise, when I looked it up, the mass-difference was much more than I expected: 2.5 times the mass of an electron (I expected not much more than the electron mass).

This is impossible, the mass of the proton is 1.67262158 × 10-27 kilograms, while the mass of the electron is 9.10938188 × 10-31 kilograms. This means that the proton has a mass more than 10^4 times that of the electron.
 
How come when a proton turns into a neutron (as in nuclear fusion in the Sun) it gives out energy AND gains in mass, where does all the extra energy come from
 
Masses given for particles are the masses of free particles. When particles bond together the created particle can have a lower mass than the sum of the constituents (to some extend one can even see this as the reason why stable bound states exist). The mass-difference is called the bonding energy.

@ArmoSkater: You seem to have mistaken my 1st post.
 
ArmoSkater87 said:
This is impossible, the mass of the proton is 1.67262158 × 10-27 kilograms, while the mass of the electron is 9.10938188 × 10-31 kilograms. This means that the proton has a mass more than 10^4 times that of the electron.

I think he means that he thought the difference in mass between a neutron and a proton would be close to the mass of an electron.
 
What, the *** are you guys talking about ?

regards
marlon
 
  • #10
They are trying to make us swallow that a neutron = a proton + an electron :-p
 
  • #11
Based upon what evidence ?

What is the underlying theory here ...

regards
marlon
 
  • #12
That would simply be wrong.
 

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