Talk:Isotopes of hydrogen

Abundance

The article seems to be either inconsistent or at least confusing about what sort of abundance of protium vs. deuterium is meant. The overview table contains values of 99.98% and 0.02%, respectively. In the List of isotopes section however, the abundances are given as 99.99% and 0.01% (when rounded correctly). There are at least two possible explanations for the apparent inconsistency: (1) Rounding error in the overview table or (2) The overview table gives abundance in terms of mass while the other table gives is as mole fraction. I'm not an expert in the field, so I'm hesitating to edit myself in fear of messing things up. Can someone help? -- Stardust canopy (talk) 08:54, 19 October 2020 (UTC)

@Stardust canopy: Actually, depending on the source of hydrogen, the values can change significantly. The problem is that 3 s.f. is not enough precision (it would round to 100% and 0%, which is not exactly an ideal way to present the information) and 4 s.f. is too much (the range of variation is within that), so I wonder what the best way to explain it should be. Double sharp (talk) 19:10, 19 October 2020 (UTC)

@Double sharp: Do we know exactly what the uncertainty is? I think it's okay to include it and give the percentages as a ± b, since any additional significant figures are uncertain but we might know how uncertain. We do the same thing for isotopic mass and half-life. ComplexRational (talk) 01:20, 20 October 2020 (UTC)

@Double sharp: Thanks for pointing this out. In order to initially narrow down the issue: Am I assuming correctly that what is meant in the "abundance" column of the overview section is mole fraction and not mass fraction? If so, we could start by correcting the values to 99.99% and 0.01%, respectively.

In a second step we could then contemplate about how to best represent uncertainties, perhaps by implementing the solution suggested by ComplexRational. On this matter: There seems to be another inconsistency in the table in the List of isotopes section. Error ranges in the "Normal proportion" and "Range of variation" column do not fully match (this cannot be due to correct rounding because both bounds are off in the same direction). Stardust canopy (talk) 09:30, 20 October 2020 (UTC)

Some background. The {{Infobox hydrogen isotopes}} is an infobox, and so aimes to give an overview of the article. Therefor it cannot be expected to be complete, precise, or detailed. Incidentally, I cannot find easily what abundance is intended. So the number change you propose may or may not be appropriate. Sure this is worth reseach, and documentation (same for place of this abundance: crust, Earth, universe?). btw, any change should be implemented consistently for all the Category:Infobox element isotopes templates (119). As for adding uncertainties to this infobox: not needed, as it is secondary info at best (secondary to the value) and so not needed for the overview task. I did not find which ComplexRational suggestion you mention. As internet and WP go: there is a link provided to the isotope article and of course there is the article itself from where this data is pulled. I strongly conclude against adding uncertainty to this infobox.

As for the #List of isotopes, and the 'Range of variation'. First, they are not 'Error ranges' as you name them, they are ranges of occurrence. (As in: different sources of material, eg seawater and rocks, can have different isotope proportions). And if I understand this math well, there is no poisson spread or sigma involved: one must assume that within the range, each value can appear equally, and to there is no 'mid-value' (as there is with common sigma-error-uncertainty). With this math, I am not sure if they must be complementary over the two isotopes.

Anyway, it is not a matter for us to "fix" this 'inconsistency'. We should not change numbers by ourselves. Our task is: check the source(s), both for values and for their meaning. -DePiep (talk) 12:03, 20 October 2020 (UTC)

This interactive chart reports the mole fraction to have the same values as shown in the verbose table of the WP article. However, the original paper is behind a paywall. Stardust canopy (talk) 15:03, 20 October 2020 (UTC)

@DePiep: Thanks for improving accuracy by pointing out the difference between experimental error and actual spread in this case. I totally agree. ComplexRational's suggestion was to add spread to the overview box. Stardust canopy (talk) 15:03, 20 October 2020 (UTC)

First of all, my post sounded too pedantic (sad face icon here), sorry for that (open hand icon here).

About CR, & noting uncertainty: not in the infobox (too much detail); as for the #List: only when in source (NUBASE, AME). To much OR. -DePiep (talk) 15:26, 20 October 2020 (UTC)

About the spread & statistics math: working with standarde atomic weights (IUPAC/CIAAW), I found this IUPAC paper on their interval notation. I don't know yet how this would translate to the spreads here; sure the statiscical background may be alike.

The current extended values (in the #List) I could not find in AME2013 nor in NUBASE2016. (from NUBASE2003? [1]). -DePiep (talk) 15:26, 20 October 2020 (UTC)

References

Confusion of two lists of references?

The reference numbers for the abundances of 1H and 2H in the table of isotopes are incorrect --76.24.24.247 (talk) 23:40, 16 March 2022 (UTC)

I think this editor (and other readers?) may have confused the list of references below the table List of isotopes with the list of references at the end of the article. For 1H and 2H the footnote 12 is supposed to indicate Reference 12 at the end of the article, which is correct as it is indeed a source for the abundances of 1H and 2H. However in the table List of isotopes, the column decay mode has footnotes [n 12] which refer to another Reference 12 in a list just below the table, which is a source for the very short-lived isotopes 6H and 7H. I suspect that 76.24.24.247 may have found that "Reference 12" and wondered why it did not refer to 1H and 2H.

Is there a way to eliminate this source of possible confusion? Perhaps there should only be one list of references in the article, and the references for the table should just be included in the general list at the end of the article, where they would have their own numbers? Dirac66 (talk) 19:14, 10 April 2022 (UTC)

Time unit abbreviation ys

Yostosecond (ys) will be an unfamiliar unit to most people and should have a verbose note to make clear the usage (especially as some people might mistake it to mean years). Can someone please add this since this is coming from a template? If this can be done in the template, it will fix the usage everywhere. Or at the very least point to Orders_of_magnitude_(time) Pmarshal (talk) 23:19, 15 July 2022 (UTC)

I agree that this would be helpful, though only for very uncommon abbreviations (shorter than nanoseconds). The alternative would be to use the exponent parameter in {{val}}, a change that would need to be implemented in each article individually. DePiep, what do you think of this? ComplexRational (talk) 00:24, 16 July 2022 (UTC)

@Pmarshal and ComplexRational: As CR suggested, I have applied {{val}} with |ul=ys unitlink set for each first appearance per section [2]. IMO this is the most appropriate way, and wiki-/web-common way, to clarify. Left the <math> decay list as is (do we link in a math line anyway?). -DePiep (talk) 06:30, 17 July 2022 (UTC)

Thanks, that ought to do it. And as for the math lines, there's already an explanatory note distinguishing y and ys. ComplexRational (talk) 14:22, 17 July 2022 (UTC)

Thank you, the link to ys should be sufficiently explicit. I think this issue is closed. Pmarshal (talk) 08:55, 21 July 2022 (UTC)

I do not consider the issue closed at all, and I was very confused for a few moments there when I found the half-life of tritium given in "y" and those of the other isotopes in "ys". Even though the article from which the figures are taken uses the "y" abbreviation to mean "year," the Wikipedia article for "year" says "The symbol 'a' is more common in scientific literature". Given that, I would suggest never ever using the abbreviation "y" when talking about science matters, but especially not here, where "y" appears to mean "yocto" in the very next line. --178.202.159.215 (talk) 23:12, 7 January 2023 (UTC)

That's an important point, but "ys" is a metric-prefixed "s", not a variant of "y", in the same way that "as" is not a variant of "a" (annum). Unfortunately the metric-prefixes and unit-suffixes are not disjoint sets of letters. MOS:CHEM does not seem to discuss choice of units, but the examples in {{Infobox element}} and {{Infobox element isotopes}} all appear to use "y" for years in half-life units. WP:PHYSICS doesn't have its own sub-MOS. Site-wide Wikipedia:Manual of Style/Dates and numbers#Units of measurement says:

a	Use a only with an SI prefix multiplier (a rock formation 540 Ma old, not Life expectancy rose to 60 a).
y or yr	See § Long periods of time for all affected units.

So I think our isotopes tables should all be consistent with each other as a primary objective, and it seems like "y" is the current site-wide standard both in this specific use-case and per a MOS that has consensus well beyond just chemistry-article editors. DMacks (talk) 23:43, 7 January 2023 (UTC)

We could surely just solve this by using plain seconds and scientific notation rather than yoctoseconds, though. Double sharp (talk) 05:23, 20 January 2024 (UTC)

Clarification of measurement uncertainty

In a similar vein as with Yostosecond/ys, I think it would be useful to have some sort of explanation for using a parenthetical for measurement uncertainty. I am unsure how best to do this; I suspect linking to Uncertainty#In_measurements would be sufficient. For reference, despite having a background in engineering, I don't recall ever seeing this notation before and had to dig around to figure out what it was. Perchy22 (talk) 03:27, 3 May 2023 (UTC)

Nun u 196.189.57.205 (talk) 07:38, 19 March 2024 (UTC)