Talk:Thorium/GA1

GA Review

Article (edit | visual edit | history) · Article talk (edit | history) · Watch

Reviewer: Parcly Taxel (talk · contribs) 03:54, 7 September 2014 (UTC)[reply]

Element 90, here we go. Parcly Taxel 03:54, 7 September 2014 (UTC)[reply]

GA review – see WP:WIAGA for criteria

Is it reasonably well written?
A. Prose is "clear and concise", without copyvios, or spelling and grammar errors:

B. MoS compliance for lead, layout, words to watch, fiction, and lists:
Is it factually accurate and verifiable?
A. Has an appropriate reference section:

B. Citation to reliable sources where necessary:

C. No original research:
Is it broad in its coverage?
A. Major aspects:

B. Focused:
Is it neutral?
Fair representation without bias:
Is it stable?
No edit wars, etc:
Does it contain images to illustrate the topic?
A. Images are tagged with their copyright status, and valid fair use rationales are provided for non-free content:

B. Images are provided if possible and are relevant to the topic, and have suitable captions:
Overall:
Pass or Fail:

1a

Again, bold text to be replaced by italic text.

Characteristics - Isotopes

"However, in deep seawaters the isotope ²³⁰Th becomes more significant and hence , which led to IUPAC reclassified reclassifying thorium as a binuclidic element in 2013."
Done Double sharp (talk) 06:12, 7 September 2014 (UTC)[reply]
- I found the section on isotopes to be confusing. At one point thorium is called mononuclidic. The it is binuclidic. Then a few paragraphs down it is monoisotopic. Can we get rid of the "howevers" and settle on one classification?Delmlsfan (talk) 00:53, 15 September 2014 (UTC)[reply]
  - @Delmlsfan: Sorry for the late response – I didn't notice this message until just now, probably because I haven't been watching the review lately (it concluded before your comment)!
  - It's confusing (hence the long reply), and it doesn't help that the definitions of "mononuclidic" and "monoisotopic" vary from source to source. IUPAC's definition of "monoisotopic" is "[an element that] has one and only one isotope that is either stable or has a half-life greater than 1×10¹⁰ a" ([1], p.708). However: IUPAC has also used "mononuclidic" to mean the very same thing! ([2], p.2053). On Wikipedia we use "mononuclidic" for the latter, and "monoisotopic" instead means an element with only one stable isotope. So you could argue that we should always be using the "-nuclidic" terms here, for Th has no stable isotope (though it has an almost-stable one, ²³²Th).
  - The unfortunate thing is that that sentence is talking about natural Th, which is nearly pure ²³²Th. Since we are referring to Th, we should be using "isotope" since the atomic number is fixed at 90. So "mononuclidic" also doesn't feel right. Argh. Changed to "isotopically pure".
  - As for "binuclidic": well, IUPAC changed its classification of Th from mononuclidic to binuclidic in 2013, because in some specific contexts the concentration ²³⁰Th is not negligible. I suspect that in general you should still be able to find references to Th as a mononuclidic, simply because if you don't restrict your attention to those cases ²³⁰Th can be neglected along with the other transient natural Th isotopes (²²⁷Th, ²²⁸Th, ²³¹Th, and ²³⁴Th).
  - (In typing the above I notice that the article treats ²²⁹Th as a synthetic radioisotope, but the infobox treats it as a natural radioisotope. I've corrected the infobox according to the article, which is cited to a reliable source. I suspect the infobox was referring to Emsley's Nature's Building Blocks, but I'm not sure: if so the article's source – the Wickleder chapter – still seems more reliable.) Double sharp (talk) 14:26, 28 January 2015 (UTC)[reply]

Occurrence

"It is a chemically unreactive phosphate mineral that has a high specific gravity and is found as yellow or brown monazite sand: ; its low reactivity makes it difficult to recover extract thorium from it."
Done Double sharp (talk) 06:12, 7 September 2014 (UTC)[reply]

Production

"…the rest of remaining rare-earth hydroxides remains remain in solution."
Done Double sharp (talk) 06:12, 7 September 2014 (UTC)[reply]

Applications - Radiometric dating

"Both of these dating methods assumes assume that the proportion of thorium-230 to thorium-232 is a constant during the time period, that the sediment layer was formed, and did not already contain thorium before contributions from the decay of uranium, and that the thorium cannot shift within the sediment layer."
Done, in a way...your correction, while not changing the meaning of the sentence, wasn't actually what I meant, so I changed it to read "Both of these dating methods assume that the proportion of thorium-230 to thorium-232 is a constant during the time period when the sediment layer was formed, that the sediment did not already contain thorium before contributions from the decay of uranium, and that the thorium cannot shift within the sediment layer." Double sharp (talk) 06:12, 7 September 2014 (UTC)[reply]

Non-nuclear

"This means that when heated to high temperatures, it does not melt, but merely glows with an intense blue light: addition . Addition of cerium dioxide gives a bright white light: ;[9] this property of thoria means that thoria and thorium nitrate are used in mantles of portable gas lights, including natural gas lamps, oil lamps and camping lights."
Done (though not quite in the way you wrote). Double sharp (talk) 06:12, 7 September 2014 (UTC)[reply]
"It has excellent optical transparency in the range of 0.35–12 µm, and its radiation is primarily due to alpha particles, which can be easily stopped by a thin cover layer of another material."
Done Double sharp (talk) 06:12, 7 September 2014 (UTC)[reply]

6b (crosses somewhat into 6a)

I am suspecting that the thorium bar image (the only non-free one in the article) isn't required, and then the monazite image from the previous section (which is free) can then be moved down. After all monazite is mentioned in the production section. Parcly Taxel 03:54, 7 September 2014 (UTC)[reply]
Done Double sharp (talk) 06:14, 7 September 2014 (UTC)[reply]