Talk:Dalton (unit): Difference between revisions
Gene Nygaard (talk | contribs) No edit summary |
How come only biological sciences use the Dalton unit? |
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:Probably in large part because that was only the convention of chemists, not physicists who used 1/16 of the naturally occuring mixture of oxygen (or maybe it was vice versa). That's where the first word in the officially recognized name of this unit comes from: '''unified atomic mass unit''', with the symbol u, is the only way this is recognized as "acceptable for use with SI". [[User:Gene Nygaard|Gene Nygaard]] 21:01, 23 September 2005 (UTC) |
:Probably in large part because that was only the convention of chemists, not physicists who used 1/16 of the naturally occuring mixture of oxygen (or maybe it was vice versa). That's where the first word in the officially recognized name of this unit comes from: '''unified atomic mass unit''', with the symbol u, is the only way this is recognized as "acceptable for use with SI". [[User:Gene Nygaard|Gene Nygaard]] 21:01, 23 September 2005 (UTC) |
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How come only biological sciences use the Dalton unit? In chemistry there is rarely a unit. The header in a table of molecular weights would be labelled 'mw' or 'molecular weight' with no unit. Just a guess, but it may be because, when talking about large molecular weights, 'kilo (no unit)' sounds kind of stupid. |
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Revision as of 19:16, 7 July 2006
Why did they choose the AMU convention of 1/12 of C12 rather than the origional standard with 1/16 016?
- Probably in large part because that was only the convention of chemists, not physicists who used 1/16 of the naturally occuring mixture of oxygen (or maybe it was vice versa). That's where the first word in the officially recognized name of this unit comes from: unified atomic mass unit, with the symbol u, is the only way this is recognized as "acceptable for use with SI". Gene Nygaard 21:01, 23 September 2005 (UTC)
How come only biological sciences use the Dalton unit? In chemistry there is rarely a unit. The header in a table of molecular weights would be labelled 'mw' or 'molecular weight' with no unit. Just a guess, but it may be because, when talking about large molecular weights, 'kilo (no unit)' sounds kind of stupid.
How do you change Atonic mass into pounds?
- via Kilograms.
I removed the following paragraph; I think it's overly simplistic and illustrates a principle of college algebra rather than of atomic masses. It is certainly not relevant to the amu unit. It also uses the term "relative atomic mass" in a strange way and. AxelBoldt 16:44, 9 Oct 2004 (UTC)
Using Mass Spectrum Data to Calculate Relative Atomic Mass
A simple calculation may be used to calculate the relative atomic mass of the sample. This is demonstrated in the following example.
| Ion | Relative Mass | Percentage Abundance |
| 11C+ | 11 | 70% |
| 13C+ | 13 | 30% |
Therefore, the relative atomic mass of the Carbon sample is:
- (70/100 x 11) + (30/100 x 13) = 7.7 + 3.9 = 11.6
[this is not the true atomic mass of carbon, it is merely illustrative]
amu to kg
the number on the page for u didn't agree exactly with the CODATA value referenced at the bottom. CODATA is state of the art, I have changed it to the CODATA value.