Talk:Helium: Difference between revisions
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stability is why it's favored over helium-4... yeah...RIDICULOUS! |
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{{WP1.0|class=FA|category=category|VA=yes|WPCD=yes|small=yes}} |
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{| class="infobox" width="238px" |
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!align="center"|[[Image:Vista-file-manager.png|50px|Archive]]<br/>[[Wikipedia:How to archive a talk page|Archives]] |
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---- |
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==Untitled== |
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*[[/Archive 1 | Archive 1:Oct 2002 – Dec 2005]] |
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*[[/Archive 2 | Archive 2:Jan - Dec 2006]] |
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*[[/Archive 3 | Archive 3:Jan - Dec 2007]] |
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|} <!-- Archive box --> |
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== Strange English in this article == |
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Strange English is in this article very early on. Look at the beginning.<br> |
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"This is due to the very high binding energy (per nucleon) of helium-4 with respect to the next three elements after helium. This helium-4 binding energy also accounts for its commonality as a product in both nuclear fusion and radioactive decay."<br> |
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"Commonality" is not the right word. Commonality means "the ordinary people, as distinguished from those with authority, rank, station, etc.," according to the RANDOM HOUSE DICTIONARY of 2012.<br> |
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What you need is "commonness": that which belongs equally to, or is shared alike by, two or more entities in question, according to the RANDOM HOUSE DICTIONARY.<br> |
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Similar results can be found in other dictionaries.[[Special:Contributions/98.67.97.60|98.67.97.60]] ([[User talk:98.67.97.60|talk]]) 04:16, 15 May 2012 (UTC) |
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== Uses of Helium - diving == |
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The section on the use of helium in diving is a bit misleading. Helium in itself does not protect against oxygen toxicity - reducing the amount of oxygen in the mix is what does that. You can achieve this by mixing helium with air and thus diluting the percentage oxygen in the mix, but there is nothing special about helium for this purpose. Helium also does not help reduce decompression time (at least for sports mixed-gas divers, I can't speak for military or commercial uses). Decompression theory is not an exact science, but many models will actually give a longer deco time if you replace nitrogen with helium. The key variable to deco timing is the percentage of oxygen in the mix (so when you reduce the oxygen percentage to avoid an oxygen tox, the trade-off is longer decompression times). The main reason for using helium in a deep diving mix is to reduce Nitrogen Narcosis. N.B. as well as the cost (helium is expensive) one of the problems of using Heliox as a dive gas is that it can affect your nervous system at depth (High Pressure Nervous Syndrome). For this reason, sports divers will normally stick with Trimix. <small>—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Rodgerclarke|Rodgerclarke]] ([[User talk:Rodgerclarke|talk]] • [[Special:Contributions/Rodgerclarke|contribs]]) 09:59, 3 February 2008 (UTC)</small><!-- Template:Unsigned --> <!--Autosigned by SineBot--> |
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:I'll fix the section so it's clear that any diluent gas can be used to protect against O2-tox. BTW, so called high pressure nervous syndrome is not a problem at most depths technical divers can reach (< 600 fsw). [http://www.scuba-doc.com/HPNS.html] Trimix is used in tech diving (almost all of which is done shallower than 600 ft!) not because of this, but because of cost. Plenty of very deep tech diving (300 to 500 fsw) has been done on straight heliox with no problem. Some (rich) divers prefer heliox because its lower density makes it easier to breathe (lower gas viscosity and density) at 10 to 20 atm. [[User:Sbharris|<font color="blue">S</font>]][[User:Sbharris|<font color="orange">B</font>]][[User:Sbharris|H]][[User:Sbharris|arris]] 10:15, 3 February 2008 (UTC) |
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== Spammers == |
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This page is being recked by spammers - I think we should go back to a point before vandalism and then lock the page if possible. <small>—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Foxfoil|Foxfoil]] ([[User talk:Foxfoil|talk]] • [[Special:Contributions/Foxfoil|contribs]]) 18:42, 5 February 2008 (UTC)</small><!-- Template:Unsigned --> <!--Autosigned by SineBot--> |
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What 'spammers' are you referring to? You're not being specific [[Special:Contributions/24.184.234.24|24.184.234.24]] ([[User talk:24.184.234.24|talk]]) 19:08, 29 May 2010 (UTC)LeucineZipper |
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== Applications has a double negative == |
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Because it is lighter than air, airships and balloons are inflated with helium for lift. In airships, helium is preferred over hydrogen because ''it is not inflammable'' and has 92.64% of the buoyancy (or lifting power) of the alternative hydrogen (see calculation.) |
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[[Special:Contributions/75.181.46.158|75.181.46.158]] ([[User talk:75.181.46.158|talk]]) 01:43, 24 February 2008 (UTC) |
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: '''Inflammable''' is a bad word, because it means both "flammable" and "not flammable." For that reason, I discourage it ever being used. Let's just use '''flammable''', which can't be misunderstood. [[User:Sbharris|<font color="blue">S</font>]][[User:Sbharris|<font color="orange">B</font>]][[User:Sbharris|H]][[User:Sbharris|arris]] 02:02, 24 February 2008 (UTC) |
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::Concurred (I am the second of now three different editors to make that wording change with comparable edit-summary). [[User:DMacks|DMacks]] ([[User talk:DMacks|talk]]) 05:39, 24 February 2008 (UTC) |
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:::Agreed. The word "flammable" is straightforward. The word "inflammable", particularly to a person whose first language is not English, looks as if it should mean the opposite. But it actually means the same. This can be confusing at best. Then to compound it further with a "not" prefix...well. "Not flammable" has a straightforward, unambiguous meaning to anyone, including those not fluent in the subtle inflections of English linguistic idiosyncracies. [[User:Feline Hymnic|Feline Hymnic]] ([[User talk:Feline Hymnic|talk]]) 09:45, 24 February 2008 (UTC) |
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: '''Inflammable''' does '''not''' mean "not flammable"! The word "flammable" is a concession to those, who never bothered to find out the meaning of "inflammable". But as even Webster & Co. gave in, so be it. <small>—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Fak119|Fak119]] ([[User talk:Fak119|talk]] • [[Special:Contributions/Fak119|contribs]]) 10:03, 25 February 2008 (UTC)</small><!-- Template:Unsigned --> <!--Autosigned by SineBot--> |
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::I agree. This is only one negative. inflammable is positive in that sense.--[[User:Stinkypie|Stinkypie]] ([[User talk:Stinkypie|talk]]) 14:51, 18 September 2008 (UTC) |
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== The picture of helium (and other gases) == |
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The picture of an empty vial in the infobox is IMHO not only useless but may lead to a false impression that helium forms a kind of a bubble in the vial. And it looks beige rather than colorless in the picture. These hold for pictures of other colorless gases, too. In my opinion these pictures should be removed ASAP. Regards, [[User:Michał Sobkowski|Michał Sobkowski]] ([[User talk:Michał Sobkowski|talk]]) 08:35, 16 March 2008 (UTC) |
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:The picture's inclusion is a residue of the systematic way minerals and elements are placed in collections for academic use. It conforms to a standard presentation, which, as you point out, is peculiar taken in isolation. |
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:It would be useful for there to be an image about helium that people could readily identify with. (The picture of a helium discharge tube seems like a step in this direction.) Failing that, there does seem to be some utility in a "seeing is believing" photo which shows, that, in observable fact, helium can't be seen. The alternative ... something along the lines of "helium can't be seen, so we aren't showing it" ... has the disadvantage that it distances a reader from an empirical observation that they could be reasonably expected to want to make for themselves. |
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:The photos in "Appearance" here and in hydrogen, kryton and neon however, are misleading, since a) they do not show any entity that is colorless, and b) have different colors. An empty test tube or bottle might work to better effect. An Appearance photo such as that in the oxygen article -- of liquid oxygen -- might be useful. |
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:[[User:Alpha Ralpha Boulevard|Alpha Ralpha Boulevard]] ([[User talk:Alpha Ralpha Boulevard|talk]]) 20:04, 27 June 2008 (UTC) |
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::A solution might be to use a pic of helium IN A DISCHARGE TUBE. Its bright yellow emission-line was observed in the Sun's corona during an eclipse, and was the reason for naming it after the sun (greek, "Helios"). [[User:SingingZombie|SingingZombie]] ([[User talk:SingingZombie|talk]]) 17:54, 26 December 2009 (UTC) |
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== Amount of Helium left? == |
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No mention in the article about the amount of helium left in the earth? I read in Wired that we had about a nine year supply at the rate we were using it currently, is this true? [[User:KiwiTallGuy|KiwiTallGuy]] ([[User talk:KiwiTallGuy|talk]]) 10:21, 15 April 2008 (UTC) |
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See the section on Natural Abundance, last paragraph. Chemist Lee Sobotka says (see reference cited) that the largest reserve in Texas has an eight-year supply at current rates, but there is more elsewhere. The reference also says that Sobotka believes that Russia will be the world's major source of helium in 30 years. [[User:Dirac66|Dirac66]] ([[User talk:Dirac66|talk]]) 13:43, 15 April 2008 (UTC) |
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== Liquid helium article == |
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There is more information in this article on liquid helium than there is in the [[Liquid helium]] article which is little more than a stub. I would think either a merge into [[Helium]] of a split out into [[Liquid helium]] would be in order. [[User:Spinningspark|<font style="background:#FFF090;color:#00C000">'''Sp<font style="background:#FFF0A0;color:#80C000">in<font style="color:#C08000">ni</font></font><font style="color:#C00000">ng</font></font><font style="color:#2820F0">Spark'''</font>]] 19:09, 15 April 2008 (UTC) |
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:Strongly concur. I think merger ''into'' [[Helium]] is in order, given how little is in the [[Liquid helium]] page. Also, there is info about liquid helium scattered throughout the page here, so seems silly to extract or rewrite that well-integrated material just to fill out a stub-page. [[User:DMacks|DMacks]] ([[User talk:DMacks|talk]]) 20:53, 15 April 2008 (UTC) |
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== language Use == |
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Helium II state |
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Liquid helium below its lambda point begins to exhibit very unusual characteristics, in a state called helium II. Boiling of helium II is not possible due to its high thermal conductivity; heat input instead causes evaporation of the liquid directly to gas. |
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The correct term for this is Sublimation link http://en.wikipedia.org/wiki/Sublimation_%28chemistry%29 not evaporation <small>—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/67.58.208.247|67.58.208.247]] ([[User talk:67.58.208.247|talk]]) 17:28, 2 May 2008 (UTC)</small><!-- Template:UnsignedIP --> <!--Autosigned by SineBot--> |
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This is a little confused. In your second sentence, I would say that evaporation of liquid helium II IS boiling of helium II. And sublimation means direct conversion of a SOLID to gas, at least for most substances which have only one liquid state. |
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For helium it is true that direct evaporation of liquid helium II without passing through liquid helium I is ANALOGOUS to sublimation of ice (for example) without passing through liquid water. However before describing the HeII --> gas transition as sublimation in a Wiki article, I think we need a reference to a reputable physics paper or website which so describes it. Without a citation, this description would be "original research" which is against Wiki policy - see [[WP:NOR]]. [[User:Dirac66|Dirac66]] ([[User talk:Dirac66|talk]]) 21:45, 2 May 2008 (UTC) |
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:How is an analogy "original research?" Inaccurate perhaps, but OR?! --[[User:Belg4mit|Belg4mit]] ([[User talk:Belg4mit|talk]]) 02:44, 4 May 2008 (UTC) |
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::Using a term in a way not used by the scientific community is OR in Wikipedia terms as it is an invention. The OP was not proposing it as an analogy, he/she was proposing it as an actual meaning. [[User:Spinningspark|<font style="background:#FFF090;color:#00C000">'''Sp<font style="background:#FFF0A0;color:#80C000">in<font style="color:#C08000">ni</font></font><font style="color:#C00000">ng</font></font><font style="color:#2820F0">Spark'''</font>]] 02:57, 4 May 2008 (UTC) |
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Although some folk pronounce the element name as HEE-lee-em, as the schwa, "ə", is carelessly used for any short vowel, it is more correctly pronounced 'um' as in 'gum', (HEE-lee-[http://en.wikipedia.org/wiki/Wikipedia:IPA_for_English#Key ʌm]), consistent with its spelling and etymology.<BR>[[User:Wikidity|Wikidity]] ([[User talk:Wikidity|talk]]) 16:07, 19 May 2011 (UTC) |
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==speach on helium[all you need to know on helium]== |
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Helium’s symbol on the periodic table is He. Its atomic number is 2 and its atomic weight is 4. It is the second lightest element after hydrogen. In its most common form, Helium 4, it has 2 Protons, Neutrons and electrons, though in its second and rare form, helium 3, it only contains one neutron. Helium has the lowest melting and boiling points of all elements being –272.2 C for the melting point and –268.93 C for the boiling point. Most of the time it is in it usual form, gas. Helium is colourless, odourless, tasteless, non-toxic, unreactive, 6 time lighter than the air we breath and part of the noble gas group of the periodic table. |
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Helium was first discovered by Pierre Janssen on the 18th of August 1868 when he came across a bright yellow line with a wavelength of 587.49nm[nanometers], in the spectrum of the chromosphere of the sun while observing an eclipse of the sun in India. Helium was then discovered by Joseph Lockyer on the 20th of October that same year while observing outer space. Lockyer concluded that it was caused by an unknown element, after unsuccessful testing to see if it were some new type of hydrogen. |
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Did you know that Helium was the first element discovered in space, before it was discovered on Earth? Also, I bet you didn’t know that Lockyer and an English chemist Edward Frankland, named the element after the Greek word for sun, Helios (written in Greek as it shows on the board). |
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Most helium on earth is stored in the natural gas field in the US. |
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In the modern universe almost all new helium is created as a result of the nuclear fusion in stars. |
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Helium is commonly used to change the pitch of a person’s voice however it is not a gas that is already in our body so it could be dangerous if too much is inhaled. One danger is as bad as death by asphyxiation (a condition of severely deficient supply of oxygen to the body) within minutes if breathing pure helium continuously. Helium is also used to inflate balloons and to make them rise to the roof or even further if released. These are common at special events, parties and celebrations. Helium is used for many other less common uses for example cryogenics (the study of very low temperatures), Deep-sea breathing gas, Cool superconducting magnets, Helium dating (a method of determining the age of a substance), Providing lift in airships such as blimps and all kinds of non-rigid airships, and as a protective gas for many industrial uses (eg. arc welding and growing silicon wafers) <small>—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Maddyson 961|Maddyson 961]] ([[User talk:Maddyson 961|talk]] • [[Special:Contributions/Maddyson 961|contribs]]) 11:05, 20 May 2008 (UTC)</small><!-- Template:Unsigned --> <!--Autosigned by SineBot--> |
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I don't see any specific information here that is not already covered in the Wikipedia article. Please clarify exactly what changes you want made. [[User:DMacks|DMacks]] ([[User talk:DMacks|talk]]) 14:31, 20 May 2008 (UTC) |
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== Applications - breathing gas for deep diving == |
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The last revision by [[User:Cryptic C62]] was useful in bringing the references for high pressure nervous syndrome and the effect of easier breathing using heliox. However, these are concerns manifested principally below 150 m. The edit removed the mention of trimix which is the gas of choice for the 40 m to 150 m range. Since the majority of deep diving is in the latter range, we have lost the principal diving use of helium and substituted its use in exoteric scenarios that is really only of relevance in the field of extreme diving. In my humble opinion, it is also a mistake to take out the mention of "narcosis", since that is what it is known as (I've never heard a diver complaining that s/he had suffered from "pressure-induced neurological symptoms"). Perhaps one interpretation of [[WP:SPADE]] might be "Don't use over-technical language when plain language will do"? |
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As much as I dislike expanding a FA into topics it's not really about, I'll try to re-instate the use of helium in trimix to avoid nitrogen narcosis and do my best to leave in the HPNS. --[[User:RexxS|RexxS]] ([[User talk:RexxS|talk]]) 21:55, 27 June 2008 (UTC) |
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==Uber-nice reference== |
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I stumped onto this document that some of you might want to use to add a bit to the history section. Enjoy! [[User:Nergaal|Nergaal]] ([[User talk:Nergaal|talk]]) 15:25, 9 July 2008 (UTC) |
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*http://minerals.usgs.gov/minerals/pubs/commodity/helium/myb1-2006-heliu.pdf |
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== Shouldnt it be == |
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colo'''u'''r? <small>—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/77.99.186.110|77.99.186.110]] ([[User talk:77.99.186.110|talk]]) 20:05, 10 July 2008 (UTC)</small><!-- Template:UnsignedIP --> <!--Autosigned by SineBot--> |
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:I don't know what "it" you're talking about, but [[WP:ENGVAR]] might answer your question. [[User:DMacks|DMacks]] ([[User talk:DMacks|talk]]) 20:32, 10 July 2008 (UTC) |
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==Effect of helium on voice== |
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I am no expert on this and i am not debating the factual accuracy of it. In the applications section it says that it affects one's timbre but not pitch. But in the biological effect section it says that it changes the timbre in a high pitched way. How is this possible? Better let someone change it before it loses it's FA status. --[[User:Stinkypie|Stinkypie]] ([[User talk:Stinkypie|talk]]) 14:56, 18 September 2008 (UTC) |
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:Those statements appear to have been present during the various FA reviews, and both statements are specifically cited. Wikipedia is a tertiary source, so we can only report what others say. If they appear to contradict, well, then they contradict--that's an attribute of ''those sources'', not our faithful reporting of them:) Please check those refs to figure out what specific technical meaning each is using here: do they mean "pitch" as the ''actual'' frequency or the ''perceived'' frequency? Ahh here we go: the bio section says "timbre in a way that makes it ''sound'' high-pitched" (emphasis mine), so that doesn't contradict a statement that the pitch ''actually'' doesn't change. [[User:DMacks|DMacks]] ([[User talk:DMacks|talk]]) 16:12, 18 September 2008 (UTC) |
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Helium gas has faster speed of sound than air, therefore as frequency is inversely proportional to the speed of sound – it is the frequency that will change. Therefore the pitch of the voice will change (to a higher pitch). 00:04, 13 August 2009 (UTC) <small><span class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Yaniss2|Yaniss2]] ([[User talk:Yaniss2|talk]] • [[Special:Contributions/Yaniss2|contribs]]) </span></small><!-- Template:Unsigned --> <!--Autosigned by SineBot--> |
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:I explain the vocal physics in more detail lower down on this TALK page, section entitled "Correction to Biological Effects". [[User:SingingZombie|SingingZombie]] ([[User talk:SingingZombie|talk]]) 16:23, 14 December 2009 (UTC) |
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== Renewability == |
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Should there be something mentioning its non-renewability? I'm no expert, but perhaps it deserves a mention somewhere, now we're in this environmentally conscious world. |
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Greeny--[[Special:Contributions/210.50.186.57|210.50.186.57]] ([[User talk:210.50.186.57|talk]]) 06:16, 27 October 2008 (UTC) |
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:Sounds like the "Occurrence and production" section would be the place. Interestingly, once He is released into the atmosphere, it's pretty much gone for good, but it is also constantly being generated inside the earth. So it's not really ''non-renewable'' in the same sense as crude oil or other mineable mineral deposits, just that we can't create it on demand like methane. [[User:DMacks|DMacks]] ([[User talk:DMacks|talk]]) 13:00, 27 October 2008 (UTC) |
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:: If I've calculated correctly with the (2008) numbers in the article, current helium extraction is ~30,000t/year, so approximately 10 times the natural generation rate of 3,000 t.--[[User:Roentgenium111|Roentgenium111]] ([[User talk:Roentgenium111|talk]]) 20:29, 25 February 2010 (UTC) |
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:::Is helium released in the atmosphere really gone for good? Does it escape into interstellar space, or is it trapped in the upper atmosphere? If it's in the upper atmosphere, why can't we find a way to capture it and reuse it?[[Special:Contributions/173.58.53.212|173.58.53.212]] ([[User talk:173.58.53.212|talk]]) <span style="font-size: smaller;" class="autosigned">—Preceding [[Wikipedia:Signatures|undated]] comment added 06:16, 9 February 2011 (UTC).</span><!--Template:Undated--> <!--Autosigned by SineBot--> |
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::::Our article states "most helium in the Earth's atmosphere escapes into space by several processes." That statement has two footnotes with references explaining the exact topic in good detail with diagrams, etc. The executive summary is "our article is correct, gone is gone...it goes up and up and up and keeps going." [[User:DMacks|DMacks]] ([[User talk:DMacks|talk]]) 13:17, 9 February 2011 (UTC) |
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::::It is not unusual for gases to escape from planetary atmospheres into space, whether in reference to Earth or Mars. All that is necessary for an object to leave Earth's gravity well "permanently" is to exceed the escape velocity of 11.2 km/s while traveling in a direction away from Earth. The kinetic theory of gases shows that some particles of gases at ordinary temperatures have a velocity far in excess of Earth's escape velocity, though not always in a direction that points away from Earth's surface. Helium has the least size and second-least mass of a particle of gas one is likely to encounter in the lower atmosphere (as it is monatomic), and the second-lowest in the extreme upper atmosphere. This means that its average velocity will be greater than for almost all other gases. So, as a volume of gas, it tends to rise to the top of Earth's atmosphere, due to its buoyancy, and as particles, it tends to leave Earth's gravity, due to its particles' velocities in excess of Earth's escape velocity. At the same time, Earth loses tons of water, oxygen and hydrogen every day, due to similar processes (though, some of that might be replaced by incoming material from space). [[User:Pooua|Pooua]] ([[User talk:Pooua|talk]]) 02:50, 29 April 2011 (UTC) |
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== [[Helium atom]] == |
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Hello, I wanted to bring attention to an article on the [[helium atom]], which currently has few articles linking to it. I think it makes sense for something in this article to link to [[helium atom]], but I wouldn't know where to insert this information. Thank you. <font color="#FF1493" face="sylfaen">[[User:LovesMacs|Loves]]</font><font color="#00BFFF" face="sylfaen">[[User:LovesMacs|Macs]]</font>[[User talk:LovesMacs| (talk)]] 00:43, 14 November 2008 (UTC) |
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:More than fixed.[[User:Sbharris|<font color="blue">S</font>]][[User:Sbharris|<font color="orange">B</font>]][[User:Sbharris|H]][[User:Sbharris|arris]] 01:30, 23 July 2009 (UTC) |
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== Density of liquid helium == |
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I believe that the density of Liquid Helium given in http://en.wikipedia.org/wiki/Helium is incorrect as 0.176 g / litre. To the best of my knowledge (and I buy the stuff by the kg), 1 litre of Liquid Helium has a mass of 0.125 kg. |
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Sincerely, |
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Andy Soper |
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+27 82 56 27037 |
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a.soper@ru.ac.za <span style="font-size: smaller;" class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/146.231.129.50|146.231.129.50]] ([[User talk:146.231.129.50|talk]]) 14:47, 4 December 2008 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot--> |
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:This site says 0.146 kg/L [http://www.chemistry.nmsu.edu/Instrumentation/LHe_Fill.html] at saturation pressure. The site in the liquid helium article says 0.125 g/mL. Clearly, unless there's that much difference in density due to pressure, we need an authoritative reference. [[User:Sbharris|<font color="blue">S</font>]][[User:Sbharris|<font color="orange">B</font>]][[User:Sbharris|H]][[User:Sbharris|arris]] 03:44, 11 December 2008 (UTC) |
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==Funny stmt== |
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'''Compounds''' section says: |
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:''These predictions may lead the collapse of helium's chemical nobility.'' |
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Are you sure? Or is the stmt simply and hillariously jumping between our mental image of the chemical properties and the chemical properties themselves? Or do we believe in magic and mind's control over matter? ... said: [[User:Rursus|Rursus]] ([[User talk:Rursus|bork²]]) 18:16, 18 January 2009 (UTC) |
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== Big Bang == |
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Am I incorrectly assuming that the Big Bang is still theoretical? I was unaware that helium could indeed be produced by a theoretical model of the creation of the universe. I would assume there would be 100% evidence for the Big Bang being the correct model of creation of the universe before stating that Helium was produced in the Big Bang, instead of being theoretically produced in it. Can we get clarification for the reason this wording was chosen? |
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: Everything in science is theoretical, but some theories are better than others. If you are unaware that helium could be produced by a theoretical model of the creation of the universe, read [[Big Bang nucleosynthesis]]. Not only does simple application of the laws of physics predict that 6 to 7 protons will be made for every neutron in the Big Bang, but it predicts that when they all combine, as well as they can in the next five minutes (or so) that is all they have have before everything cools and expands too much for any more fusion, that the "ash" of the process will consist of about 24% by weight of helium-4, and 76% hydrogen. Which is just what we see in our own gas giants and the spectra of stars everywhere else in the universe. So that's impressive, inasmuch as the theory was not tinkered with to make it "come up with" the right answer on helium abundance. And yet it does. [[User:Sbharris|<font color="blue">S</font>]][[User:Sbharris|<font color="orange">B</font>]][[User:Sbharris|H]][[User:Sbharris|arris]] 21:49, 5 May 2009 (UTC) |
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::First i must say this page is truly great, but as a physics prof. i must say that the individual is correct in saying we can not without some plausible doubt say that heliums mass creation was caused by the big bang. There are to many opposing theories. I am now 62 years old and if it one thing i have learned is do not close the door on alternate theories. I would not have caught this but a student told me that wikipedia said that it was a fact. So please realize you are not only stating a theory(even if it is a great one)as a fact, but you are misleading many who read this. PS I gave him an A on the paper and made him write another about the big bang and steady state theories <span style="font-size: smaller;" class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/68.115.131.180|68.115.131.180]] ([[User talk:68.115.131.180|talk]]) 15:00, 17 June 2009 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot--> |
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:::If someone is going to pretend to be a professor, maybe they should remember how to write correctly!? [[Special:Contributions/24.21.10.30|24.21.10.30]] ([[User talk:24.21.10.30|talk]]) 19:38, 24 August 2009 (UTC) |
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::::Let's give people the benefit of the doubt. Talk pages don't exactly have high standards for grammar and few people in their 60s know how to type fast, let alone well. --[[user:mav|mav]] (please help review [[User:Deckiller/FAC urgents | urgent FAC and FARs]]) 01:13, 29 December 2009 (UTC) |
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:::That is a silly notion. The person in question is an OBVIOUS pretender, and he deserved to be called OUT on that. Not being able to capitalize correctly, not to punctuate correctly, and not to spell correctly are NOT grammatical problems, anyway, but they are obvious signs of being a phony. Also, they are signs of a phony without any sense of pride.[[Special:Contributions/98.67.97.60|98.67.97.60]] ([[User talk:98.67.97.60|talk]]) 04:32, 15 May 2012 (UTC) |
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::Am I incorrectly assuming that the Big Bang is still theoretical? I was unaware that helium could indeed be produced by a theoretical model of the creation of the universe...instead of being theoretically produced in it. Can we get clarification for the reason this wording was chosen?<br> |
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::Theoretical models do not produce anything tangible at all, including helium! |
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::Theoretical models produce NUMBERS and words. His statements were yet another arrant piece of evidence that "physics prof" is merely a faker.[[Special:Contributions/98.67.97.60|98.67.97.60]] ([[User talk:98.67.97.60|talk]]) |
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::Forgive me if the article has been edited previously, but I believe the way the article mentions the Big Bang is fine. It describes it as "It is believed that," which does not imply fact; instead, it implies a theory that is generally accepted, which is accurate. [[User:Zoughtbaj|Zoughtbaj]] ([[User talk:Zoughtbaj|talk]]) 18:47, 3 July 2012 (UTC) |
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== Etymology == |
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Is it worth mentioning in the article that helium got its anomalous -ium suffix because Lockyer and Frankland assumed that the new element would be a metal? The irksome thing is that, while I'm utterly sure that this is so, I can't find an unambiguous reference to cite - can any of you do better? [[User:Kay Dekker|Kay Dekker]] ([[User talk:Kay Dekker|talk]]) 23:02, 21 May 2009 (UTC) |
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:Are you sure there was a rule to have the suffix "ium" only for metals? There are other counterexamples to this "rule": [[selenium]], [[germanium]], [[polonium]] - a non-metal and two metalloids. And current [[IUPAC]] rules propose that newly-discovered elements must all end in "ium", whether they're metals or not. --[[User:Roentgenium111|Roentgenium111]] ([[User talk:Roentgenium111|talk]]) 22:22, 4 August 2010 (UTC) |
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I'm not sure about the "ium" suffix only applying to metals, but it is anomalous when applied to a gas. All the noble gases have "on"; there are others ("gen"),, but no other gas has the "ium" suffix. ([[Special:Contributions/124.170.61.239|124.170.61.239]] ([[User talk:124.170.61.239|talk]]) 13:55, 11 July 2011 (UTC)) |
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== Spelling error == |
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In this article, the word "elegant" is misspelled "elligant". |
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:Thanks! [[User:Materialscientist|Materialscientist]] ([[User talk:Materialscientist|talk]]) 22:25, 6 July 2009 (UTC) |
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== Would somebody please re-sprotect this page? == |
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All the common element articles are excessively IP vandalized, and it's starting now again. [[User:Sbharris|<font color="blue">S</font>]][[User:Sbharris|<font color="orange">B</font>]][[User:Sbharris|H]][[User:Sbharris|arris]] 18:45, 28 September 2009 (UTC) |
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==Correction to Biological Effects== |
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The explanation of the high pitch you get when you huff helium began by saying something very wrong: that the pitch of the voice is primarily determined by the dimensions of the resonant cavity, not by the stimulating frequency from the vocal folds. You can easily demonstrate how wrong this is by singing and sliding gradually from low pitch to high pitch, all on the same vowel. The resonance chamber from larynx to mouth plus buzz in the skull and sinuses changes only very little, but the pitch changes more than an octave and covers all the pitches between. That means if the cavity were determining pitch, you'd need to be gradually reducing its size for high notes to less than HALF the size for low notes! (For a trained singer with a two-octave range, to less than ONE QUARTER the low-note size.) No. In fact the vocal cavity, like the body of a stringed instrument, is a versatile resonator capable of supporting many frequencies, and what changes is the tension holding the vocal folds together, and the air pressure from below. |
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The reason the cavity can resonate at many frequencies without changing its dimensions (much) is, it's not like a trombone, which is a simple narrow cylinder, with length much greater than base-radius. The only available path for a sound wave through a trombone is directly from one end to the other, so the pitch is determined by the length, the wavelength of the sound being equal to the length of the cylinder, or an harmonic fraction thereof. In contrast, the voice is better-modelled as a WIDE cylinder, a can, with a pinhole in the center of the bottom, through which vibratory stimulation radiates into the can in all different directions. The path of the resonating wave through the vocal cavity can be direct from entrance to exit, as in a trombone, but it can also be crooked, ricocheting off the walls of the can. This makes many additional baseline resonant frequencies available, plus their harmonics, and the distribution of them--which of the possible vibrations actually occur, and how strongly--is determined primarily by the stimulating vibration, as in a stringed instrument, exactly opposite to what the article said. |
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Fortunately, I was able to correct this simply by deleting the misinformation, so I have not added any new reference to the article. However, if you want one, here it is: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2689615/ |
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[[User:SingingZombie|SingingZombie]] ([[User talk:SingingZombie|talk]]) 10:33, 14 December 2009 (UTC) |
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: There's an argument over whether the pitch changes at all when you breathe helium. To me, it sounds as if it does. Several speech professionals claim it does not, precisely for the reasons you give (it's an oscillator-driven system not a resonator-driven one). Basically, even if you're breathing 80% helium, 20% oxygen, your vocal folds resonate at the same frequency, and all that changes is the timbre (strength of the various higher harmonics), not the fundamental pitch. Right now I'm sort of agnostic on the issue, not having had the time or the helium to do my own experiments. This article has said in the past that helium does and does NOT change the pitch of the voice. And you can find "explanations" that say both things on the net. If you're doing to go with your idea, you have to go whole hog with J. Wolfe's idea that timbre changes but pitch does NOT. See [http://www.phys.unsw.edu.au/jw/speechmodel.html] [[User:Sbharris|<font color="blue">S</font>]][[User:Sbharris|<font color="orange">B</font>]][[User:Sbharris|H]][[User:Sbharris|arris]] 03:23, 15 December 2009 (UTC) |
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::Wanna hear something even cooler? The vocal cavity is wide in the larynx up to behind the tongue, where it is narrow, and then it widens again in the mouth-and-sinuses. So it has a peanut-shape (or barbel-shape), just like the body of a guitar or violin! There must be something about the peanut-shape which confers extra resonances. |
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::By the way, I agree with you about the pitch/timbre ambiguity. That's one of the reasons I just deleted the misinfo but did not add new info. [[User:SingingZombie|SingingZombie]] ([[User talk:SingingZombie|talk]]) 17:20, 15 December 2009 (UTC) |
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:::Note that J. Wolfe on the helium-singing article is the same guy on the article you cited. He's a wonk in the field. Wolfe and I had some correspondance in which I essentially said: "well, if the pitch doesn't change, how come everybody thinks it does, and why does it SOUND like it does? To which he essentially replied: "It doesn't sound like it does to ME, and here are the spectral analyses that show that the harmonics are separated by just the same interval on helium, which means that the fundamental (the pitch by definition, even if it's heard as a virtual pitch) is unchanged." So the harmonic power spectum of the voice (particularly amplitude of higher harmonics) is changed by helium, resulting in a major timbre change, but that's it. <p> We really have to do something about this on the Wikipedia, since if Wolfe is right, the article still remains wrong. Probably this topic deserves its own subarticle, there's so much confusion about it even in the cited literature. I've probably read about 3 different explanation of why helium changes voice pitch, but the biggest academic in the field claims it doesn't change it at all. Go figure. [[User:Sbharris|<font color="blue">S</font>]][[User:Sbharris|<font color="orange">B</font>]][[User:Sbharris|H]][[User:Sbharris|arris]] 20:15, 15 December 2009 (UTC) |
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::::I think the way the article reads now is fine--"...an increase in the pitch of the resonance frequencies..." Whether it's the overall pitch that changes or only the timbre, the pitches of the individual resonance modes certainly do change. If the pitch doesn't change (as Wolfe says) it's because the relative activities of the resonances also change to maintain the overall pitch, but not the timbre. The pitches of the individual modes--for instance, the shortest mode, straight up from larynx to mouth with no richochets--definitely does change its pitch, according to the change in the speed of sound. [[User:SingingZombie|SingingZombie]] ([[User talk:SingingZombie|talk]]) 06:47, 16 December 2009 (UTC) |
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:::Yes. A spectral analysis of some spoken words showed the basis tone stays the same under helium, but overtones become higher. People trying to speak with helium often raise there basis tone unconsciously and so distort the effect of helium alone. At the very end of breathing out the helium concentration and the effect is reduced. --[[User:Helium4|Helium4]] ([[User talk:Helium4|talk]]) 14:52, 18 August 2010 (UTC) |
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==Elemental mass== |
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Correction to the opening paragraph of the main article: Helium is believed to make up 24 percent of the elemental (i.e., baryonic) mass of the universe (consisting of protons, neutrons, etc.), not the total mass. Most of the mass of the universe is currently believed to be non-baryonic, namely dark matter and dark energy. Compare the opening paragraph of the Wikipedia main article on "Hydrogen". <span style="font-size: smaller;" class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/76.90.2.195|76.90.2.195]] ([[User talk:76.90.2.195|talk]]) 06:11, 25 January 2010 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot--> |
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:I added "elemental" to the lead, but note also that it talks about our galaxy, not universe. [[User:Materialscientist|Materialscientist]] ([[User talk:Materialscientist|talk]]) 06:26, 25 January 2010 (UTC) |
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== "End helium's chemical nobility" == |
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The last sentence of the first paragraph of [[Helium#Compounds]] says, "If confirmed by experiment such compounds will end helium's chemical nobility, and the only remaining noble element will be neon." This seems to be a strange thing to say. For one thing, as has been previously pointed out under "[[Talk:Helium#Funny stmt|Funny stmt]]", our experimental confirmation of helium compounds will not change helium's inertness itself—it will only modify whether we believe it is inert or not. Additionally, I don't know whether "nobility" is the right term here. We still refer to all of the group 18 elements as [[noble gas]]es, even though we know some of them form chemical compounds, right? I don't feel comfortable enough with my meager grasp of chemistry to change the sentence itself, so could someone address this, please? —[[User:Bkell|Bkell]] ([[User talk:Bkell|talk]]) 17:52, 28 February 2010 (UTC) |
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:You are right. These used to be known as the "inert gasses." When scientists began forming compounds with them in the 1960s, "inert" was dropped, and the group became known as the "noble gasses," which does not mean that they cannot form compounds, only that it is difficult to do so. [[User:Plazak|Plazak]] ([[User talk:Plazak|talk]]) 18:00, 28 February 2010 (UTC) |
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== How rare are helium burning stars? == |
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The article says that "only the very heaviest stars" produce helium ("at the very end of their lives"). Does anyone have the [[percentage]] of such stars? It's not like they are all 'blue supergiants', I have read that even [[Hertzprung-Russel diagram|type K]] will engage in some [[helium burning]], which includes nearly all of those stars that expired by now. But these really are less abundant than less massive stars. <span style="font-size: smaller;" class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/24.184.234.24|24.184.234.24]] ([[User talk:24.184.234.24|talk]]) 19:14, 29 May 2010 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot--> |
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[[Special:Contributions/24.184.234.24|24.184.234.24]] ([[User talk:24.184.234.24|talk]]) 19:19, 29 May 2010 (UTC)LeucineZipper |
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:It actually says 'all but very heaviest stars' produce helium. [[User:Ruslik0|Ruslik]]_[[User Talk:Ruslik0|<span style="color:red">Zero</span>]] 19:38, 29 May 2010 (UTC) |
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::It says this "Some new helium is being created presently as a result of the nuclear fusion of hydrogen, in all but the very heaviest stars, which fuse helium into heavier elements at the extreme ends of their lives." The comma is what confuses this. Either way it's read, that helium is produced in all but the heaviest stars, or only the heaviest stars can fuse helium, is incorrect. Stars less than 0.5 solar masses cannot fuse helium. The largest stars may have exhausted hydrogen fuel so are no longer creating helium. The source for this information is the [[Stellar Evolution]] article. I am going to align the information in this article with the Stellar Evolution article. Rather than making vague references to massive stars (i.e. what is a massive star? Bigger than Sol or what?) I am going to insert the actual information. <small><span class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:D3333b|D3333b]] ([[User talk:D3333b|talk]] • [[Special:Contributions/D3333b|contribs]]) 22:34, 20 June 2010 (UTC)</span></small><!-- Template:Unsigned --> <!--Autosigned by SineBot--> |
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::It also stated this: "Such stars are massive and therefore rare, and this fact accounts for the fact that all other chemical elements after" in regards to stars that can fuse helium. Massive stars are generally considered to be much larger than the sun. The sun can fuse helium though, and in fact stars down to half the size of the sun can, according to the [[Stellar Evolution]] article. I deleted the comment about "such stars are massive and therefore rare", since it is in contradiction with the authoritative article on stellar evolution, and has no citation, but I left the information in about the relative abundance of elements. Someone else is going to have to figure out what constitutes a "massive star" and what constitutes "rare." It's probably better to use actual data here than vague statements, and if the statement is adjusted further then it should agree with [[Stellar Evolution]]. <small><span class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:D3333b|D3333b]] ([[User talk:D3333b|talk]] • [[Special:Contributions/D3333b|contribs]]) 22:41, 20 June 2010 (UTC)</span></small><!-- Template:Unsigned --> <!--Autosigned by SineBot--> |
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== Picture to scale? == |
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The first picture under the heading "Characteristics" (the big one which shows the electron distribution and the nucleus with a black bar that is one Å) does not look like it is to scale, yet gives the impression that it is. For it to be to scale you would have to fit 100,000 of the pink dots in the center side by side on the black line. To me it looks like you might be able to fit 100 times at the most. If I'm right, I think someone should clarify in the text that the size of the electron cloud and the nucleus isn't to scale in the picture, or another picture should be chosen. |
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On a slightly different, more uncertain note, I thought the electron distribution would look different. In the picture it seems like it just steadily decreases outwards from a maximum at the nucleus, but I thought there was a region of low probability around the center, climbing from 0 at the nucleus to a maximum some distance out and then decreasing like in the picture. This might also be because of strange scales in the pic though. --[[User:Knuthove|Knuthove]] 22:14, June 1, 2010 (UTC) |
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:Actually, the 1s orbital in which helium's two electrons are has no wave nodes, implying that the region of the highest probability of finding the electrons is actually on the nucleus itself. Nevertheless, the "average radius" of the electrons is non-zero because there is a lower but non-zero probability of finding the electrons outside the nucleus as well. It is misleading to imagine that the orbital is a shell (like a thin eggshell) where the electrons spend most of their time; in reality they spend most of their time very near the nucleus (or even interpenetrating the nucleus---at the subatomic level this is perfectly possible, if counterintuitive to us who are used to macroscopic properties of matter). Of course, the p orbitals have a node at the nucleus, so p electrons actually have zero probability of being found at the nucleus, but spend all their time away from it. That's not the case here, though, since helium in its ground state has both electrons in the 1s orbital.—[[User:Tetracube|Tetracube]] ([[User talk:Tetracube|talk]]) 22:48, 1 June 2010 (UTC) |
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:P.S. Also, the caption explicitly says that the depiction of the nucleus is merely an illustration; in actuality, the two protons and two neutrons interpenetrate and occupy the same spherical area. (Or at least, their probability densities occupy exactly the same area---it's impossible to say whether their "actual positions", if such a thing exists at that level, coincide or not, due to the uncertainty principle.)—[[User:Tetracube|Tetracube]] ([[User talk:Tetracube|talk]]) 22:54, 1 June 2010 (UTC) |
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== Medical Use, Transition Turbulent-Laminar == |
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Not yet included in the article is what I heard: Helium is used in medical intensive care, if a narrow breathing path makes breathing difficult. Helium has about the same viscosity resistance in comparison to air, as long as laminar flows are compared. Air flow gets - according to higher density and therefore higher [[Reynolds number|Reynolds number Re]] earlier turbulent than the less dense helium, and turbulent flow makes more resistance than. Re grows relevant high if one breathes gas at the - compared to normal - rather high pressure of the ambiance while diving deep in water, or breathing organs are constricted. See articles |
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http://www.ncbi.nlm.nih.gov/pubmed/12627000 and |
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http://copd.about.com/gi/o.htm?zi=1/XJ&zTi=1&sdn=copd&cdn=health&tm=269&f=00&su=p736.9.336.ip_&tt=2&bt=0&bts=0&zu=http%3A//www.pubmedcentral.nih.gov/articlerender.fcgi%3Fartid%3D137275 and |
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http://copd.about.com/gi/o.htm?zi=1/XJ&zTi=1&sdn=copd&cdn=health&tm=272&f=00&su=p736.9.336.ip_&tt=2&bt=0&bts=0&zu=http%3A//www.rtmagazine.com/issues/articles/1999-04_10.asp |
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An aluminium 2-Groschen coin (Austria, about 1950-2000, lightweight with 0,9 g) rolls out in an upright fixed round latex balloon of about 28 cm diameter for up to 2,75 min if filled with helium, but only 2,25 min if air-filled. This is why - hearable - turbulences brake rather quickly down the speed of the coin to a gas-characteristic transition speed to laminar flow, which is lower for air than for helium. --[[User:Helium4|Helium4]] ([[User talk:Helium4|talk]]) 15:09, 18 August 2010 (UTC) |
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==Helium production== |
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The following paragraph in the Helium article is an abomination of nuclear physics and the standard solar model. Therefore, it must be deleted before it does any more harm. |
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"In a similar way, the particular energetic stability of the helium-4 nucleus, produced by similar effects, accounts for the ease of helium-4 production in atomic reactions involving both heavy-particle emission, and fusion. Some stable helium-3 is produced in fusion reactions from hydrogen, but it is a very small fraction, compared with the highly favorable helium-4. The stability of helium-4 is the reason hydrogen is converted to helium-4 (not deuterium or helium-3 or heavier elements) in the Sun..." |
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WOW! Not only is helium-3 '''stable''', it is also '''far''' more abundant in the sun than helium-4. Additionally, helium-3 is required for '''every''' fusion reaction resulting in helium-4, not to mention that deuterium is necessary to make helium-3. The reason that helium-4 is more abundant on Earth is that helium-4's rest mass (added with the rest masses of the other particles that result) is less than the initial system's rest masses. Saying that helium-4's "higher" (are there various degrees of stable? I thought stable meant stable?) stability is why it is favored over helium-3 is like saying carbon-12's (another isotope made in solar processes) stability is why it's favored over helium-4... yeah...RIDICULOUS! |
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The worst part is, this disgusting edit has been around for almost a '''YEAR''' without anybody changing it. FOR SHAME! |
The worst part is, this disgusting edit has been around for almost a '''YEAR''' without anybody changing it. FOR SHAME! |
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[[User:Mrkbh12|Mrkbh12]] ([[User talk:Mrkbh12|talk]]) 00:07, 17 September 2010 (UTC) |
[[User:Mrkbh12|Mrkbh12]] ([[User talk:Mrkbh12|talk]]) 00:07, 17 September 2010 (UTC) |
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Can you support the assertion that 3He is more abundant than 4He in the Sun? It is my understanding that (1) the abundance of 3He in |
Can you support the assertion that 3He is more abundant than 4He in the Sun? It is my understanding that (1) the abundance of 3He in thuchdiuchuchch uex euc LDUDCN<dj-ewudn;EICUNSD;jchiudfvhjdkscn c al_elements]], and also in the solar wind[[http://deepblue.lib.umich.edu/bitstream/2027.42/43785/1/11214_2004_Article_184086.pdf]], and (3) 3He is probably not a significant participant in solar reactions[[http://www.nrao.edu/pr/2002/he3/]]. I believe the concentration in the solar wind approximates that on at leascjnalkjvdcj ncjn jkchv sxn DCK D-3730E7DHA;LZBHAES;E5 |
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[[User:Fnj2|Fnj2]] ([[User talk:Fnj2|talk]]) 06:36, 30 October 2010 (UTC) |
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==Internally inconsistent and unsupported assertion== |
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"In 2000[update], the U.S. has proven helium reserves, in such gas well complexes, of about 147 billion standard cubic feet (42 billion SCM). This is enough helium for about 25 years of world use, or 35 years of U.S. use, although factors in saving and processing impact effective reserve numbers.[78][79]" |
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First of all, there are 35.3 cu ft in 1 m^3, so either the 147 figure or the 42 figure is obviously wrong. Further, neither of the two references given mentions EITHER figure. Neither reference is a primary or authoritative reference, anyway. |
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Somebody with the time, either fix this or rip it out. |
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[[User:Fnj2|Fnj2]] ([[User talk:Fnj2|talk]]) 06:03, 30 October 2010 (UTC) |
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:Removed the distracting refs 78,79 - you've got to search the last ref (former 80, now 78). [[User:Materialscientist|Materialscientist]] ([[User talk:Materialscientist|talk]]) 06:37, 30 October 2010 (UTC) |
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:: Did that, and thanks for pointing this out. The exact ref for the 147 billion SCF is [http://www.nap.edu/openbook.php?record_id=9860&page=44], see table. The 42 billion SCM is off by an exact factor of 10 due to a math error, and should be 4.2 billion SCM. To get a naive time before it's gone, divide the 4.2 billion SCM US reserves, by 72 million SCM/US use per year (see pie chart) and obtain 58 years. I don't know where the 25 came from. I've fixed the ref. and the conversion. The time to run out is in the ballpark, but may be off by a factor of 2.[[User:Sbharris|<font color="blue">S</font>]][[User:Sbharris|<font color="orange">B</font>]][[User:Sbharris|H]][[User:Sbharris|arris]] 06:43, 30 October 2010 (UTC) |
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== Heat capacity: Constant volume or pressure == |
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Why is it that hardly anybody cares to specify if a listed value for the heat capacity of a gas is measured under constant volume or constant pressure? The numbers are significantly different, and lead to very wrong results if one condition is implicitly assumed while the figure in fact was measured under the other. Since He is very close to an ideal gas it is fairly easy to confirm that the listed number in the article is for constant pressure, I will change the article to specify that. In many other articles the given numbers are useless! [[User:WikiPidi|WikiPidi]] ([[User talk:WikiPidi|talk]]) 14:32, 8 November 2010 (UTC) |
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:Hmm, seems it's not that easy, as nested templates are used. I've brought the issue up on the Template:Infobox_element talk page [[User:WikiPidi|WikiPidi]] ([[User talk:WikiPidi|talk]]) 15:51, 8 November 2010 (UTC) |
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:: This particular heat capacity of 20.786 J/mole/K is exactly 2.5000 R (to 5 sig digits!), so obviously it's constant '''pressure''' [[heat capacity]] for a monatomic gas. Furthermore, exactly the same figure is given for the the other 4 noble gases Ne,Ar,Kr,Xe. This is fishy, as real substances rarely show the same heat capacity to 5 sig digits, even when it is the correct one. Even fishier still, radon is also listed as having the same heat capacity of 20.786 J/mole/K, which means this is certainly a calculated not a measured value, since nobody has collected enough radon to measure its heat capacity to that value (radon itself produces so much heat from its own decay that this would be a difficult and perilous measurement to even get an estimate for). SO at this point I have to say is '''TILT'''. Calculated values from theory should be marked so. [[User:Sbharris|<font color="blue">S</font>]][[User:Sbharris|<font color="orange">B</font>]][[User:Sbharris|H]][[User:Sbharris|arris]] 17:29, 8 November 2010 (UTC) |
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== Edit request from 71.227.76.96, 17 December 2010 == |
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{{Tld|Edit semi-protected}} |
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Revision as of 14:52, 16 April 2013
stability is why it's favored over helium-4... yeah...RIDICULOUS!
The worst part is, this disgusting edit has been around for almost a YEAR without anybody changing it. FOR SHAME!
Mrkbh12 (talk) 00:07, 17 September 2010 (UTC)
Can you support the assertion that 3He is more abundant than 4He in the Sun? It is my understanding that (1) the abundance of 3He in thuchdiuchuchch uex euc LDUDCN<dj-ewudn;EICUNSD;jchiudfvhjdkscn c al_elements]], and also in the solar wind[[1]], and (3) 3He is probably not a significant participant in solar reactions[[2]]. I believe the concentration in the solar wind approximates that on at leascjnalkjvdcj ncjn jkchv sxn DCK D-3730E7DHA;LZBHAES;E5
On 18-08-1868, a solar eclipse day a French scientist Janssen took spectrometer readings from this fort Vijaydurg, one of the oldest forts on sindhudurga coast of India. The stone benches he used for taking the readings are known as “saheb’s kattas” in local language. These spectrometer readings helped in detecting the presence of “Helium”, one of the basic elements on Sun http://www.konkanonline.com/Sindhudurg/Vijaydurg-Fort.html
- Is this a reliable source? Ruslik_Zero 20:20, 17 December 2010 (UTC)
Interesting. The date is the same, and eclipses last such a sort time that he can't have the data from two sites. The article states that it was the eclipse of Guntur, India, but that doesn't mean that the total-eclipse ground track was ONLY at Guntur. These things pass in a linear arc typically for long distances. Janssen may well have been somewhere near, like Vijaydurg fort, in which case it's a simple matter to put in "Vijaydurg fort, during the Guntur, India eclipse of 18 Aug, 1868." I'd like another cite (the WP article on Vijaydurg fort says the same, but uses the same cite), and will look at the web to see if this is mention in any chem histories. How far is Vijaydurg from Guntur, anyway?
This [3] cite gives Vijaydurg fort as the location of the English Platform from which the Englishman J. Norman Lockyear took eclipse readings in 1898. But that isn't right for many reasons, as Lockyear took his readings in 1868, the same year as Janssen, but several months later and not necessarily during an eclipse (evidence is that it was not). This grows ever more mysterious. There was an important eclipse in India in 1898, but none of these helium people took part in that, even if the English did build a "platform". And I very much doubt it would have been in the same part of India anyway.
The wiki article on the eclipse of 18 Aug, 1868, here [4] concludes on the basis of Wikibios that Janssen was in Guntur and Lockyear in Vijaydurg. But that does not make sense, as Lockyear observed helium in non-eclipse situation a month after Janssen, and was not in India at all, but at home in the UK (I just confirmed that). Nevertheless, Janssen's report from India and Lockyear's from the UK arrived at the French Academy on the same day, so they are often treated as codiscoverers. Interestingly, Janssen had constructed the first spectroheliograph soon after the eclipse, and proven to himself that he could see the helium line at the Sun's limb, without needing an eclipse, starting very soon after the eclipse. So he also knew this before Lockyear independently discovered the fact.
Janssen (head of the French team to go to India for the eclipse of 18 Aug 1868) most certainly DID go to India, and saw the Aug 18, 1868 eclipse there at a "camp" near Guntur (Guntoor) town (that might be Vijaydurg fort, or it might not). There was a also a British team there for the same purpose, led by a Col. Tennant, in the same area and the same track, that also saw the eclipse and the helium line (TENNANT might have been at Vijaydurg, especially if the platform there is really an "English platform" for observing that eclipse, and not a French one). The eclipse track was said to have passed through the modern state of Andhra Pradesh [5]. The camps could have been anywhere in the track. Here is more [6] This traveler is unaware that Lockyear didn't go to India. But if these are English platforms perhaps they were built by the Tennant English team, and Lockyear is known to have looked at both the French and the English results (which both showed the helium line) and conclude (from England) that a new element was present, and not sodium. SBHarris 01:26, 18 December 2010 (UTC)
Arbitrary break
There are two article of Jansen describing his trip to the eclips and two biographies:
- The Total Solar Eclipse of August 1868. Part I.
- The Total Solar Eclipse of August 1868. Part II.
- Jules Janssen (1824–1907): From ophthalmology to astronomy doi:10.1007/BF00155012
- Pierre Jules Cesar Janssen
If they do not mention anything ....... --Stone (talk) 09:10, 18 December 2010 (UTC)
- He writes himself: My observatory was set up at the house of M. Jules Lafaucheur, who kindly placed at my disposal all the first floor of his house, the highest and best situated in Guntoor. Portions of his first floor communicate with a large terrace upon which I had erected a temporary building, answering the purpose of our observations. --Stone (talk) 09:17, 18 December 2010 (UTC)
- This one [7] also gives a good description.--Stone (talk) 13:15, 18 December 2010 (UTC)
- He writes himself: My observatory was set up at the house of M. Jules Lafaucheur, who kindly placed at my disposal all the first floor of his house, the highest and best situated in Guntoor. Portions of his first floor communicate with a large terrace upon which I had erected a temporary building, answering the purpose of our observations. --Stone (talk) 09:17, 18 December 2010 (UTC)
Even James Francis Tennant was not there, but in book [8] it is said that one JPEC sponsored expedition made camp and an abandoned coastal for. --Stone (talk) 15:54, 18 December 2010 (UTC)
- [9] states that the Joint Permanent Eclipse Committee JPEC was foundedn 1894. You can't belief what you read.--Stone (talk) 16:00, 18 December 2010 (UTC)
[10] states that Maunder in 1898 could not go to Viziadrug because Lockyer was observing there.--Stone (talk) 20:04, 18 December 2010 (UTC)
- COMMENT: Well, Viziadrug is indeed our Vijaydurg, so it's probable that Lockyear observed the India eclipse of 1898 indeed there, and perhaps the "English platform" is thus his, from THAT year. But he had long since helped discover helium back in 1868 (30 years before), and that while he was in England, not India. So the mixup is understandable. The eclipse of 1898 in India (which is a known and separate event) didn't have anything to do with helium.
Thanks for the definitive word on where Janssen was for the 1868 Indian eclipse, in which the first use of a spectroscope on an eclipse discovered helium-- he was indeed in Guntur, not in Vijaydurg fort. We still don't know where "Col. Tennant" and the English team in India for 1868 were. I'm not even sure that the "Col. Tennant" who led the English eclipse team to India in 1868 is the same James Francis Tennant, scientist. He may be. But if James F. Tennant, scientist, wasn't in India to see the elicpse of 1868, then these are two different Tennants. SBHarris 01:55, 19 December 2010 (UTC)
- [11] Tennant is the same Tannant. My be I wrote it wrong. He was not at Viziadru, but he was in India! He staid in the house Mr Wilson the sub-collector of Gumtoor and made his observations from the garden of that house. Jannsen was a half mile west of his position.--Stone (talk) 08:03, 19 December 2010 (UTC)
- Then I think we've gotten to the bottom of this. Two teams were in India for the Guntur eclipse in 1868, both seeing helium lines for the first time, one English (Tennant's) and one French (Janssen's). Both were near Guntur, neither near Vijaydurg. Janssen, using the first spectrograph on the Sun, found he could see these new lines even when no eclipse was going on, if he aimed near the Sun's limb, to pick up some hot corona. Lockyear in England discovered even before Janssen told him, that he could see helium lines with a spectroscope in England, with no eclipse. He interpreted Janssen and Tennant's data as that of a new element.
The eclipse of 1898 30 years later, was one in which Lockyear participated directly from India. Apparently he did build the platform at Vijaydurg fort for this, but he wasn't interested in finding helium-- all that had been long settled. But the rumors that Vigjaydurg had something to do with finding helium in India persist, due the confusion between the eclipses of 1868 and 1898, and Lockyear (codiscoverer of helium) being personally present in India in Vijaydurg IN 1898 for the eclipse of that year (he hadn't been to India in 1868). You didn't write it wrong. Your source says Viziadrug and that's simply another name for Vijaydurg. Lockyear was there, 30 years after helium's discovery, doing something else with THAT eclipse. SBHarris 09:50, 19 December 2010 (UTC)
- Then I think we've gotten to the bottom of this. Two teams were in India for the Guntur eclipse in 1868, both seeing helium lines for the first time, one English (Tennant's) and one French (Janssen's). Both were near Guntur, neither near Vijaydurg. Janssen, using the first spectrograph on the Sun, found he could see these new lines even when no eclipse was going on, if he aimed near the Sun's limb, to pick up some hot corona. Lockyear in England discovered even before Janssen told him, that he could see helium lines with a spectroscope in England, with no eclipse. He interpreted Janssen and Tennant's data as that of a new element.
- [11] Tennant is the same Tannant. My be I wrote it wrong. He was not at Viziadru, but he was in India! He staid in the house Mr Wilson the sub-collector of Gumtoor and made his observations from the garden of that house. Jannsen was a half mile west of his position.--Stone (talk) 08:03, 19 December 2010 (UTC)
I think when I read the Lockyear article he makes clear that the eclipse data from India was not used for his findings of Helium. Neither was the data from Jannsen nor from any other eclipse source. He said that all he needed was derived from his own data collected in his garden in London.
One book I mentioned above states for the 1868 eclipse one JPEC sponsored expedition made camp and an abandoned coastal fort the path of the eclipse is going over Vijaydurgand they only used places which were either reachable by train or had a harbour. This makes clear that even in 1868 it might be possible to have some English astronomers at the fort. The platform might be from the 1868 or 1898 expedition, but helium was neither discovered there nor was data used from this expedition for the discovery.--Stone (talk) 11:18, 19 December 2010 (UTC) After a long look into the literature on that topic the edit request finally is declined.--Stone (talk) 11:59, 22 December 2010 (UTC)
Color of Helium II
What color is Helium II liquid? Does anyone have access to a link to a color photograph of it? Keraunos (talk) 05:14, 6 January 2011 (UTC)
![](http://upload.wikimedia.org/wikipedia/commons/thumb/f/f8/Liquid_helium_Rollin_film.jpg/200px-Liquid_helium_Rollin_film.jpg)
This is a black and white photo, but there's no reason to think it's colored. It's described as colorless, just as helium I is. Actually, on closer look the color photo used in this article is a closeup of THIS photo, so the color photo shows superfluid helium already. I'll re-label it. SBHarris 23:06, 9 February 2011 (UTC)
Earth's Helium Reserves to run out in 25 years
Can someone please add this info in the article? It says it's semi-protected and I don't know how to edit it Source: http://www.dailymail.co.uk/sciencetech/article-1305386/Earths-helium-reserves-run-25-years.html
Thanks!
I think reading:
Reserve, Committee on Understanding the Impact of Selling the Helium; Board, National Materials Advisory; Council, National Research (2010-06-30). Selling the Nation's Helium Reserve. ISBN 9780309149792.
makes me think we still have some helium.
And: The helium is produced by alpha decay in the earth's interior so there will be always new helium we can use.
--Stone (talk) 22:39, 4 March 2011 (UTC)
Wasting of Helium
It seems to me that it would be useful to have an image of helium being wasted uselessly. The photo of the Flying house reenactment of the movie "Up" seems perfect for this. Perhaps someone can upload it to wikimedia commons ? 91.182.130.233 (talk) 10:05, 23 March 2011 (UTC)
Typo
Liquid density of Helium at M.P. is 0.125 instead of 0.145. Can be verified by using a number of external sources. —Preceding unsigned comment added by 192.194.251.123 (talk) 18:13, 18 May 2011 (UTC)
- Helium density decreases from 0.145 to 0.125 between 0 and 4 K, see, e.g. Lide, D. R., ed. (2005). CRC Handbook of Chemistry and Physics (86th ed.). Boca Raton (FL): CRC Press. p. 6-120. ISBN 0-8493-0486-5.. Materialscientist (talk) 01:01, 26 May 2011 (UTC)
Glow color discrepancy
![](http://upload.wikimedia.org/wikipedia/commons/thumb/8/82/Helium_discharge_tube.jpg/220px-Helium_discharge_tube.jpg)
![](http://upload.wikimedia.org/wikipedia/commons/thumb/0/00/Helium-glow.jpg/220px-Helium-glow.jpg)
Current Infobox text: "Appearance: [...] exhibiting a purple glow when placed in a high voltage electric field"
Which image and color is "correct"? --Cybercobra (talk) 07:52, 26 July 2011 (UTC)
- See Wikipedia:Featured picture candidates/Oxygen glowing for a long discussion...the tube shown in the previous image is not professionally made, water might have entered during the manufacturing process. User:Materialscientist removed the images, then I added A-hp's images - uploaded by A-hp himself - ([12]) so that we would at least have a good representation. Lanthanum-138 (talk) 11:25, 26 July 2011 (UTC)
Molar Heat Capacity 5R/2 Wrong ?
As I'm only reading up on this right now (learning), not sure if I'm correct but the Physical Properties side panel shows the Molar Heat Capacity as 5R/2 whereas this Wiki page http://en.wikipedia.org/wiki/Heat_capacity (Half way down at the heading "The simple case of the monatomic gas" states it should be 3R/2 for all monatomic gases ???? — Preceding unsigned comment added by 86.41.81.212 (talk) 23:29, 9 September 2011 (UTC)
Aha ... Thx ... back to learning then :-) — Preceding unsigned comment added by 86.41.81.212 (talk) 00:40, 10 September 2011 (UTC)
Swedish scientists emanating from Uranium
erm... "two Swedish chemists, Per Teodor Cleve and Nils Abraham Langlet, emanating from the uranium ore cleveite"?? Neat trick! Can this be rephrased?Plantsurfer (talk) 22:34, 6 December 2011 (UTC)
- They were very emanent scientists. SBHarris 22:36, 6 December 2011 (UTC)
Just a clarification
I think the following paragraph:
"By 1995, a billion cubic meters of the gas had been collected and the reserve was US$1.4 billion in debt, prompting the Congress of the United States in 1996 to phase out the reserve.[4][28] The resulting "Helium Privatization Act of 1996"[29] (Public Law 104–273) directed the United States Department of the Interior to start emptying the reserve by 2005."
would be clearer if phrased:
"By 1995, a billion cubic meters of the gas had been collected and the reserve was US$1.4 billion in debt, prompting the Congress of the United States in 1996 to phase out the reserve.[4][28] The resulting "Helium Privatization Act of 1996"[29] (Public Law 104–273) directed the United States Department of the Interior to empty the reserve, starting no later than 2005."
As it is it can be read that the plan was that the reserve would be emptied by 2005. Thanks. Peculiarist (talk) 03:39, 5 January 2012 (UTC)
Use in suicides
I just came across Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi:10.1111/j.1556-4029.2011.01723.x, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with |doi=10.1111/j.1556-4029.2011.01723.x
instead. which discusses how helium is increasingly being used in suicides in Australia and similar data has come out from the UK (not anywhere near an RS, but the data is from an RS). Should we include this? SmartSE (talk) 18:31, 17 January 2012 (UTC)
- Perhaps. More material on helium's use in this fashion is already quoted in the wiki on suicide bag. The mechanism is discussed at controlled atmosphere killing and nitrogen asphyxiation, which is mostly about capital punishment where nitrogen (nor helium) has ever been used, and which I'm trying to get renamed to inert gas asphyxiation, with subarticles or subsections on different inert gases and homicide vs. suicide. I could use some help on this from editors here, as the nitrogen asphyxiation article seems to be WP:OWNed by one or two editors who are resistant to making any changes in it.
Helium is particularly suitable for inert gas asphyxiation suicide, since it collects at the top of do-it-yourself apparatuses, forming a layer around the head. Otherwise, it's not much different from equally affordable argon or nitrogen. SBHarris 19:53, 15 May 2012 (UTC)
- 42 died in Britain last year due to helium!. The Guardian doesn't explain why... but perhaps it's due to suicides. Either way, it should be covered here in depth. The current article suggests there are few safety issues.Malick78 (talk) 12:07, 29 August 2012 (UTC)
Natural Abundance
Can the following phrase "thus an Earthly helium balloon is essentially a bag of retired alpha particles." be made a bit more encyclopdedic? (For want of a better word) — Preceding unsigned comment added by 216.36.132.66 (talk) 17:30, 19 January 2012 (UTC)
- Removed that bit as unnecessary. Materialscientist (talk) 07:50, 21 January 2012 (UTC)
Bulk Modulus of LHe
In the liquid helium section of this article, it is stated that the bulk modulus of LHe is ~50MPa, and there's a reference to an article discussing solid helium. I believe this is incorrect and that figure probably relates to solid helium. A more commonly assumed/cited bulk modulus of liquid helium is 268 Bar (~27MPa), according to Pressure-volume-temperature relations in liquid and solid4He - E.R. Grilly, J. Low Temp. Phys. 11, 33 (1973). http://www.springerlink.com/content/m3175u35hgnq0127/ — Preceding unsigned comment added by 87.194.174.73 (talk) 20:07, 13 April 2012 (UTC)
- Corrected, thanks. A note for readers: Grilly talks about compressibility, which is inverse of the bulk modulus; its value has a significant temperature dependence, especially at the lambda point, and 27 MPa is just an indicative value at approx. 2 K. Materialscientist (talk) 06:26, 16 April 2012 (UTC)
Wrong history
Now we have it: Nature's Building Blocks: Everything You Need to Know About the Elements 2011 gives us the "real" history of Lockyear in Vijaydurg India in 1868. This contradicting his (Lockyers) own description of the events. So do not quote this 2011 version of John Emsley for the discovery of helium, he is wrong.--Stone (talk) 07:25, 15 May 2012 (UTC)
- Nature's Building Blocks: Everything You Need to Know About the Elements 2003 So do
notquote this 2003 version of John Emsley for the discovery of helium, in which he iswrongright.--Stone (talk) 08:30, 15 May 2012 (UTC)- What? You mean Lockyear's own account is wrong (which wouldn't be the first time that first-person historical accounts are inflated), but Emsley's historical account, based on many sources, is correct? So we SHOULD quote Emsley? SBHarris 19:45, 15 May 2012 (UTC)
- Sorry, I meant the second Emsley is right from 2003. The newest version of Emsley is wrong and is contradicting the written report of Lockyer from 1868. So lets stick to the old and right version.--Stone (talk) 06:04, 16 May 2012 (UTC)
- Okay, I didn't notice the different dates at the end of the two Emsley links. I've taken the liberty of adding them in bold to your comments above. If that's not okay with you, of course remove them. SBHarris 18:34, 16 May 2012 (UTC)
- I will try to contact Emsley, I only found his phone number and no mail so I try to call him.--Stone (talk) 11:53, 17 May 2012 (UTC)
- I am in contact with Emsley and we try to figure out the story will having a look into the available documents.--Stone (talk) 21:03, 22 July 2012 (UTC)
- I will try to contact Emsley, I only found his phone number and no mail so I try to call him.--Stone (talk) 11:53, 17 May 2012 (UTC)
- Okay, I didn't notice the different dates at the end of the two Emsley links. I've taken the liberty of adding them in bold to your comments above. If that's not okay with you, of course remove them. SBHarris 18:34, 16 May 2012 (UTC)
- Sorry, I meant the second Emsley is right from 2003. The newest version of Emsley is wrong and is contradicting the written report of Lockyer from 1868. So lets stick to the old and right version.--Stone (talk) 06:04, 16 May 2012 (UTC)
- What? You mean Lockyear's own account is wrong (which wouldn't be the first time that first-person historical accounts are inflated), but Emsley's historical account, based on many sources, is correct? So we SHOULD quote Emsley? SBHarris 19:45, 15 May 2012 (UTC)
Upper-atmospheric harvesting of helium?
Gases tend to naturally sort themselves by molecular weight, and all of our "lost" helium hasn't actually left the planet. It's just way up in the sky in a hard to access location.
Would it ever be economically feasible to harvest helium from the upper atmosphere, compress and liquify it, and send a container of liquid helium back down to the Earth?
If the concept of a space elevator ever gets off the ground, it could be used as a helium transport method.
DMahalko (talk) 23:19, 26 June 2012 (UTC)
- Do you really think that if you leave a bottle of vodka on the shelf long enough, that the alcohol in it will rise to the top, like cream on whole milk just out of the cow? Sorry, my friend, but nature doesn't work that way. Liquid separation only works when intermolecular forces allow aggregates to form that are large enough that the bouyancy forces on them are large enough compared with the mixing caused by thermal impacts (Brownian motion on this scale). But in a microemulsion separation never happens. Nor does it happen in gases. Oxygen is heavier than nitrogen, but the composition of the atmosphere at sea level is the same as on the top of Mr. Everest. Helium does NOT selectively drift up to the top of the atmosphere. It mixes uniformly, as does the neon that has always been in it. SBHarris 21:25, 22 July 2012 (UTC)
Second least reactive element?
How can this be true? What then is the least reactive element?
Asgrrr (talk) 13:14, 1 February 2013 (UTC)
This must be wrong then, or confusingly worded:
"Helium is the least reactive noble gas after neon and thus the second least reactive of all elements"
Does it mean that Neon is more reactive than Helium, therefore Helium is "after" Neon, or the other way around? This is not good wording.
Asgrrr (talk) 15:06, 1 February 2013 (UTC)
- It means Ne is even less reactive than He, so He is the least reactive after Ne. Double sharp (talk) 15:25, 1 February 2013 (UTC)