Talk:Sulfur

Isotopes
Hi editors! I'm trying to verify the Isotopes section, and I came across these...


 * 1) In whole 24 (according to a provided source) or 23, 25 (according to others) isotopes of sulfur with atomic weights from 26 to 49 are known. The mass of particles for 26, 27, 46-49, as well as the half-life for 26, 47, and 48 are not determined out of experimental data. Thus, may it be said, that only 18 sulfur isotopes are experimentally identified? How many isotopes do exist?
 * According to NUBASE2020, which is the most recent compilation of nuclear data, a total of 23 isotopes from 27S to 49S inclusive have been experimentally identified, and I'm not aware of confirmed reports of other isotopes in the literature. However, half-lives and decay modes have not been measured for all of them. Complex / Rational  15:55, 14 January 2023 (UTC)
 * 1) Information about the S-32 isotope somehow fell into the Natural occurrence section, I would convey it to the Isotopes. In addition, almost every Wikipedia related material explains this isotope formation more or less successively (burning of silicon Si-28, that formed as a result of fusion of two O-16 in a supernova). The exception is the Isotopes of Sulfur article where we have as though S-32 is originally formed from C-12 capturing five He-4. Is this the same process? The last explanation looks fragmented or wrong. What is in fact? I suggest this information, and the rest text of the section as well is copied from one source. I don't know whether this source is copyrighted, but the text is replicated to a word on a few places of the Internet. If the source is wrong, should it be cast out?
 * I suspect that the text, which is more complete in the lead of Isotopes of sulfur, actually originated on Wikipedia and was then copied elsewhere on the internet. Some of it existed here since 2007, with details about stellar nucleosynthesis added later, and the earliest snapshot of the other website on the Wayback Machine dates to 2015 with a publication date of 2013. Many external websites don't properly credit Wikipedia when they copy text from here.
 * You are correct in that two nucleosynthesis processes are being described: the alpha ladder (12C + 5 4He → 32S, one step at a time) and oxygen-burning process (16O + 16O → 28Si + 4He, followed by 28Si + 4He → 32S). They definitely need to be distinguished; I can take a closer look later at how to do so. A brief note may be appropriate in the isotopes section, but I believe this is more pertinent to natural occurrence, in the sense that these mechanisms are the astrophysical origin of sulfur in the universe. Complex / Rational  15:55, 14 January 2023 (UTC)
 * Hi! I just read this in the text and it seemed wrong? "On the planet Earth the sulfur isotopic composition was determined by the Sun." I thought earth's composition was determined by previous nova, the debris of which (plus other material) determined the composition of both the earth and the sun? Eccentricorbit (talk) 14:40, 23 February 2024 (UTC)
 * 1) Anyway, I tried to extract some knowledge from that text, like that (plus one other source)... The S-34 content varies in different samples of sediment ores, compared with the ocean water. Assaying of the S-32:S-34 isotopes ratio (delta-S-34 or Δ34S) in the samples allows to make suggestions about their chemical history. For example, it allows to age-date the samples, estimate temperature of equilibrium between ore and water, determine pH and oxygen fugacity, identify the activity of sulfate-reducing bacteria in the time of formation of the sample, or suggest the main sources of sulfur in ecosystems. For example, the Rocky Mountains lakes get sulfates mainly from the atmosphere.
 * Feel free to correct the text as you see fit. Complex / Rational  15:55, 14 January 2023 (UTC)
 * 1) Yes, the radioactive S-35 isotope is formed in cosmic ray spallation of Ar-40, I would add "of atmospheric Ar-40". Also I would add that this isotope may be obtained artificially by different ways, and in practice a reaction Cl-35 + n -> S-35 + p, that runs at irradiation potassium chloride by neutrons, is used. The isotope S-35 is used in various sulfur-containing compound as a radioactive tracer for many biological studies, for example it was used in the Hershey-Chase experiment. Working with the compounds containing this isotope is relatively safe, under condition of not falling those compounds inside an organism of an experimenter.
 * I can also look into this; a summary of synthesis and applications of sulfur-35 would definitely be helpful, though if you wish to go into greater detail, a subsection Isotopes of sulfur may be more appropriate. In general, though, feel free to be bold and make these changes yourself. Complex / Rational  15:55, 14 January 2023 (UTC)

Tosha Langue (talk) 18:39, 13 January 2023 (UTC)

Cut the content
I have withdrawn the following from the article: "Aluminium sulfate is used in the purification of drinking water, wastewater treatment plants and papermaking.."

The reason of removal is that the toxicity of Aluminium sulfate is provided by Al3+, not by sulfate. Please consider incorporation of this content to more suitable article, if needed. Tosha Langue (talk) 05:31, 23 October 2023 (UTC)

Biological role of sulfate
Biological role needs a subsection on the role of sulfate and sulfation, such as: Also needs at least a mention of molybdenum cofactor. Unfortunately I'm not well-read enough to author such a section. 2A02:1812:1126:5D00:396E:A1ED:7C5A:C557 (talk) 21:23, 2 March 2024 (UTC)
 * 1) sulfolipids
 * 2) sulfated carbohydrates (e.g. keratan sulfate, chondroitin sulfate, heparin)
 * 3) sulfation as a step in the detoxification of xenobiotics, etc.

Properties
According to trusted book Poling, B. E., Prausnitz, J. M., & O’Connell, J. P. (2000). The Properties of Gases and Liquids (5th ed.). McGraw-Hill. the melting point is 119.6 deg.C, not 115. I did change in the text but don't know how to change this in side panel info. Please help. Thanks Czakolo (talk) 10:33, 18 March 2024 (UTC)


 * currently given boiling point of 115 C is NOT correct and the reference someone provided in my comment DOES NOT even include this value! According to Poling, B. E., Prausnitz, J. M., & O’Connell, J. P. (2000) the correct value is 392.75 K (which is 119.6 C)

This book is professional, scientific resource easily accessible by any good researcher or academic professor, so should be easy to check. Czakolo (talk) 11:37, 18 March 2024 (UTC)


 * The question is about melting point (freezing point), not boiling point, as you wrote, @Czakolo. I have checked both sources, Poling-Prausnitz-O'Connel (yours) and Greenwood-Earnshaw (presented in the article), and both mention the temperature 119.6°C. However, Greenwood and Earnshaw specified this figure to the beta-S8 allotrope, clarifying in the text, that slow transition from one alfa-allotrope to the beta, as well as the presence of the microcrystalline form, may alter the melting point in the range 114.6-120.4°C. Tosha Langue (talk) 15:28, 18 March 2024 (UTC)
 * sorry, my bad in second text, I meant freezing. Then, it should be corrected to say 119.6 for the most dominant allotrope in liquid form and give the range with the explanation of when it may be altered. I believe 115 is misleading. Thanks for correction! Czakolo (talk) 18:18, 18 March 2024 (UTC)
 * I can do the respective edits, but later. Let us have time for other editors' opinions... Tosha Langue (talk) 01:26, 19 March 2024 (UTC)