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Is Methane gas and (its associated components and) general gas as expelled in the act of flatus and defecation heavier or lighter than air? I need to change clothes daily in a public toilet and it often stinks to the point of having to hold my breath. Am I better off taking a breath when I change my shoes, or by standing on my toes? Google has not been of much help. Please assume good faith. Thanks. Anton. 81.131.40.58 (talk) 10:56, 13 January 2020 (UTC)[reply]
Methane is odorless. (Gas as distributed in homes smells because they include an additive so that people can detect gas leaks.)
Assuming good faith against my better judgement for the last part... It does not fall under "google it yourself" but it still falls under "try it yourself". (The only way to answer from theory would be a combination of physiology of odor perception, chemistry of human waste composition and volatile compounds, and fluid dynamics in a 3D simulation of air motion in the place; the whole edifice would be extremely shaky.) TigraanClick here to contact me 11:59, 13 January 2020 (UTC)[reply]
The density of a gas is (to a good approximation, if the pressure isn't too high) proportional to its molecular mass. Therefore, methane (m = 16 u) is less dense than air (average m = 29 u). If you ask about flatulence, this article (which you could have found if you'd have read the article) provides data from 16 subjects - in some of them, there was so much carbon dioxide that the resulting gas mixture would be denser than air, in some less dense. Notice that there will be some water vapor in addition which is less dense than air.
But that's all assuming that the expelled gas and air have the same temperature, which generally isn't the case. Gas in the intestine has body temperature, and the public toilet is probably cooler. However, there will be a slight cooling due to the change in pressure when the gas is expelled (Joule–Thomson effect) - you can do some research on the pressure involved.
Notice that these effects which might make the expelled gases rise or fall are short-lived, as there will likely be convection in the restroom. And also, though slower, gas diffusion.
The other question was about the smell of feces, and I guess that in this case the gases in the vicinity of the feces, a mixture of air and the emanating gases, will typically be less dense than air because most of the emanation will be water vapor, and humidity of the surrounding air may be kept below 100%.
The smell is hydrogen sulfide and other thiols. These are present in low concentrations, but your nose is exquisitely sensitive to them. Given that, I'm not sure there will be much of an effect from positioning yourself differently; the concentration gradient in the room probably isn't very large. If the smell is constant, it's quite likely sewer gas leaking from fixtures with defective traps, or some other plumbing defect that lets the gas in. --47.146.63.87 (talk) 23:45, 13 January 2020 (UTC)[reply]
Tangentially relevant is olfactory fatigue. Smells you have been continuously exposed to tend to fade for you, even if the substance is still present. --Jayron32 15:48, 14 January 2020 (UTC)[reply]
FWIW - a draft "ScienceNews template" (see copy below) has been created - QUESTION: Is such a template (or equivalent) useful anywhere on Wikipedia? - Comments Welcome - in any case - Enjoy! :) Drbogdan (talk) 15:30, 13 January 2020 (UTC)[reply]
I don't see where it would be useful, and even if it was, it certainly wouldn't be in this horrifically sensationalist form. "Awesome facts"? Random all caps? "FACT=>"? I'm not believing anything in this listicle even though I know the facts are true. Fgf10 (talk) 17:18, 13 January 2020 (UTC)[reply]
@Fgf10: Thank you *very much* for your comments - they're appreciated - yes - *entirely* agree - template style could be toned-down and presented better, while maintaining the same facts (template style was somewhat influenced by trying to better communicate with some young students in my local area - but also - to be more accessible and useful to the average reader - after all => "Readability of Wikipedia Articles" (BEST? => Score of 60/"9th grade/14yo" level)[1]) - in any case - Thanks again for your comments - and - Enjoy! :) Drbogdan (talk) 17:53, 13 January 2020 (UTC)[reply]
There are many dubious statements here, and also misleading links. Some is speculation, guesses or estimates. When I see the qualifer "fact" at the front, I can expect to be deceived. I do agree that it is an amazing list however! Also the linking to external sites is not our way to do things here. It would be better to link to an article or subsection that covers this statement in detail.Graeme Bartlett (talk) 00:12, 14 January 2020 (UTC)[reply]
@Graeme Bartlett: Thank you for your reply - and taking the time to comment - yes - also agree - seems the layout, text and links could be better managed - choosing a useful place on Wikipedia to apply such a template, even after all's been sorted out to everyone's likings, may be a challenge - perhaps the "Science" article may be a possibility? - there may be other places on Wikipedia that such a (more finished) template may be useful as well? - iac - Thanks again for your comments - Enjoy! :) Drbogdan (talk) 01:32, 14 January 2020 (UTC)[reply]
It could go on the Portal:Science if it exists. Though I don't know who uses that. Another possibility is that it could make a one time appearance in the Signpost. Graeme Bartlett (talk) 06:27, 14 January 2020 (UTC)[reply]
As others have noted, the sensationalism looks very out of place. Also, this is not really the correct venue for this kind of question - we're here to answer fact-based questions. I guess the better place would be on the Village Pump. When bringing the subect up, it would be helpful to include how you intend it to work and what needs it fills. Are you just doing this yourself? How often are you doing it? Are you going to pitch a fit if a hundred people come in and change the entire thing around every minute of the day? Remember that there is no WP:OWNERSHIP on WP so you will have no control over what happens to it. IMO, it has no place here; the fact that you're here looking for a place to shoe-horn it in suggests you already know that. Generally speaking, it's much better to see a problem and then fix it than to design something and see what problems it might apply to. Matt Deres (talk) 17:47, 14 January 2020 (UTC)[reply]
@Matt Deres: Thank you for your comments - yes - *entirely* agree - the above QUESTION has now been posted on "WP:Village Pump" as suggested - at => "VP-IdeaLab" and "VP-Technical" - also - no problem whatsoever - it's *entirely* ok with me to rv/rm/mv/ce the template contents - or any other contributions I've made over the years - I've claimed no "WP:Ownership" over any of my edits on Wikipedia, and fully understand that the editing process on Wikipedia is a collaborative effort (per "WP:OWN") - my objective here is to see if the concept (in some form) has a place on Wikipedia - or not - it's *entirely* ok with me either way of course - in any case - Enjoy! :) Drbogdan (talk) 20:11, 14 January 2020 (UTC)[reply]
NOTE: a new version (hopefully improved to the better Wikipedia standards) of the template has now been created - and, if interested, may be viewed below and/or here => "User:Drbogdan/ScienceFacts" - Thanks again for all the earlier comments - newer Comments Welcome - Enjoy! :) Drbogdan (talk) 16:23, 17 January 2020 (UTC)[reply]
^Bogdan, Dr. Dennis (February 16, 2020). "The one particular chemical is Nucleic Acid - a basic chemical for all known life forms - in the form of DNA - and/or - RNA - that defines - by way of a particular genetic code sequence - all the astronomically diverse known life forms on Earth - all such known life forms are essentially a variation of this particular Nucleic Acid chemical that, at a very basic level, has been uniquely coded for a specific known life form". Dr. Dennis Bogdan.
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