What does it mean by 1 amu? The mass of a proton?

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Discussion Overview

The discussion revolves around the concept of atomic mass units (amu), specifically what constitutes 1 amu and how it relates to the mass of protons, neutrons, and electrons in an atom, using oxygen as a reference point. Participants explore definitions, implications, and the relationship between atomic mass and the components of an atom.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants question whether 1 amu refers to the mass of a proton, neutron, or electron, and seek clarification on what the 16 amu of an oxygen atom represents.
  • There are repeated calls for a clear definition of amu, with some participants expressing frustration over the lack of provided sources.
  • One participant suggests that 1 amu is defined as 1/12th the mass of a C-12 isotope and approximately equals 1.66 x 10-24 grams, indicating that the mass of oxygen-16 does not simply add up from its constituent protons and neutrons.
  • Another participant expresses confusion over why basic information was not searched for online, implying that the questions posed are easily answerable through research.
  • Concerns are raised about the appropriateness of the questions being asked by one participant, suggesting they may not align with the expected knowledge level of someone with an undergraduate degree in science.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the clarity of the definition of amu or the appropriateness of the questions being asked. Multiple viewpoints regarding the understanding of amu and its implications remain contested.

Contextual Notes

Some participants highlight the complexity of atomic mass calculations, noting that the mass of an atom does not correspond directly to the sum of its protons, neutrons, and electrons, which may require further exploration of nuclear binding energy and other factors.

Who May Find This Useful

This discussion may be of interest to students and individuals seeking to understand atomic mass units and their application in chemistry and physics, particularly those grappling with foundational concepts in atomic structure.

HCverma
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Member advised to do at least some basic research before posting
What does it mean by 1 amu? the mass of a proton or a neutron or an electron? If the mass of O is 16 amu, then what makes 16 amu in O atom? 16 protons or 16 neutrons or 16 electrons?
 
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There is a clear and unambiguous definition of the amu, have you checked it?
 
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Borek said:
There is a clear and unambiguous definition of the amu, have you checked it?
Where is the definition? I don't see it. Could you provide the link, please?
 
HCverma said:
Where is the definition? I don't see it. Could you provide the link, please?

I don't quite understand why you did not google this. Is there a reason why?

Zz.
 
HCverma said:
What does it mean by 1 amu? the mass of a proton or a neutron or an electron? If the mass of O is 16 amu, then what makes 16 amu in O atom? 16 protons or 16 neutrons or 16 electrons?
I would recommend Googling: unified atomic mass unit

And when you find the entry at Wikipedia, pay close attention to one word; "One unified atomic mass unit is approximately the mass of one nucleon"

As, if you do some maths, you will find that Oxygen-16's mass isn't quite what the masses of Oxygen-16's protons, neutrons, and electrons, add up to.

In other words, 1 amu is NOT based on the individual masses of the protons, neutrons, and electrons.
 
ZapperZ said:
I don't quite understand why you did not google this. Is there a reason why?

Zz.
Thanks a lot for the suggestion.
 
HCverma said:
What does it mean by 1 amu? the mass of a proton or a neutron or an electron? If the mass of O is 16 amu, then what makes 16 amu in O atom? 16 protons or 16 neutrons or 16 electrons?
1 amu is a reference taken by scientists to measure the mass of elements. Actally 1 amu=1/12th mass of one C-12 isotope and 1amu=1.66 *10-24grams
 
Inderjeet Singh1208 said:
1 amu is a reference taken by scientists to measure the mass of elements. Actally 1 amu=1/12th mass of one C-12 isotope and 1amu=1.66 *10-24grams

... which is something one can easily find with a simple googling. It was why I asked the OP why he didn't do this in the first place. His response appears to look as if this was not even something that he thought of doing, which I find rather puzzling.

Zz.
 
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@HCverma

I cannot help but notice a pattern on your postings.

You have posted several questions on this forum which have very simple answers. Simple as in the sense, browsing through the book or Google or thinking clearly could have solved them.

Yet in your profile it says that you have completed undergrad in Bsc.

Do these questions suit a person who has completed a degree?

https://www.physicsforums.com/threads/in-circular-motion-what-does-it-mean-s-r-th.952979/

https://www.physicsforums.com/threa...something-having-of-mass.952560/#post-6035200

https://www.physicsforums.com/threa...lorophyll-is-it-possible.952553/#post-6034721

https://www.physicsforums.com/threa...h4-and-1-molecule-of-ch4.952196/#post-6031717

https://www.physicsforums.com/threads/when-the-nucleus-of-h-atom-is-neutral.953581/

Maybe you can clarify to prove me wrong?

Else I would say that this warning is fair and you should clear your basic concepts first before rushing to PF to post problems.
 
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