Talk:Helium
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Article changed over to new Wikipedia:WikiProject Elements format by maveric149. Elementbox converted 15:39, 23 Jun 2005 by Femto (previous revision was that of 19:31, 20 Jun 2005).
[edit] So the question is...
If Helium is as abundant as it sounds... than how much in density/volume mass does it occur in the average in space? If you can answer this... please do!
- If you mean the universe, probably a similar ratio as there are stars to the volume of space (I don't know). It is not found floating around in empty space though, mostly just in stars. (Do you think this should be clarified in the article?) —Centrx→talk • 16:37, 22 August 2006 (UTC)
[edit] Extraction and use doesn't have enough information
The Extraction and Use section reads more like a "History of Helium" chapter. More information is needed on how helium is obtained, whether all of it comes from the ground or if other methods can be used to obtain it, and so forth. -Rolypolyman 21:44, 25 January 2007 (UTC)
- The "Extraction and Use" section is a subsection of "History", that is, it is about the "History of Helium". The information you seek is available in the "Extraction" section under "Occurrence and Production". A renaming of the section headers may be warranted, or a see also. —Centrx→talk • 01:51, 26 January 2007 (UTC)
[edit] Lung Collapse
Helium may also cause Lung Collapse--68.207.206.69 02:57, 29 January 2007 (UTC)
- The statement in the cited article: "BLM disclaimer: Inhaling helium is not a good idea. Because helium is less dense than air, inhaling it creates the potential for collapsed lungs. Really.", seems like it was made as a twisted scary statement to ward laypersons off from trying it. The article's focus isn't on the dangers, it's a press release on the supply of helium. Atropos235 05:44, 12 March 2007 (UTC)
[edit] Crystal structure of helium
I'm not positive about this, but according to Web Elements’ helium crystal page, helium typically has a face-centered cubic structure. This is the same structure as the Kepler conjecture and forms the pyramid of cannonballs shown here. From what I can gather by googling on the subject, the body-centered cubic structure is a special, extra-high pressure form. I hope someone looks into this and makes the necessary corrections. As I am not expert in these matters — and don't desire to be — I hope someone who knows for sure will post a comment here. If no one ever bothers to comment, and the current two cyrstal structures stay (“hexagonal or bcc”), then after a week or so, I may change it to “FCC and BCC” (and then catch hell). Greg L 01:59, 16 February 2007 (UTC)
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- Well, no one stepped up to the plate and addressed this so far. But here's what I've found: In accordance with Web Elements’ helium crystal page,, cubic-closest packing is the crystal form favored by the inert gases. This is because the van der Waals forces between these atoms have highly isotropic interactions so each atom prefers to have maximum contact with neighbors. Due to its extremely weak heat of fusion (only 21 mJ mol−1), helium does not freeze — even at absolute zero — at room pressure and must be under 25 bar of pressure to crystallize. But when it finally does so, it assumes the thermodynamically most favored crystal structure: cubic closest-packing. In cubic closest-packing, a given atom is in contact with the maximum possible number of neighbors: 12 (6 in the same plane, 3 above the plane, and 3 below the plane). As such for sphere packing, it has the mathematically maximum efficiency of 74%.
I've further found that there are two patterns for closest-packed: hexagonal closest packing (HCP) as well as “face-centered cubic” (FCC). I see that metals such as most of the platinum-group metals plus gold and silver crystallize in a cubic closest-packed structure. And not surprisingly, the crystal form of silver and gold actually found in the field is the octahedron (which is one of the repeating crystalline forms of the FCC unit cell). Since all the other noble gases are FCC, and since Web Elements also says that helium is fcc, I’ve changed the article accordingly. I've dropped "body-centered cubic" so it now says "fcc and hexagonal". Greg L 18:48, 17 February 2007 (UTC)
- Well, no one stepped up to the plate and addressed this so far. But here's what I've found: In accordance with Web Elements’ helium crystal page,, cubic-closest packing is the crystal form favored by the inert gases. This is because the van der Waals forces between these atoms have highly isotropic interactions so each atom prefers to have maximum contact with neighbors. Due to its extremely weak heat of fusion (only 21 mJ mol−1), helium does not freeze — even at absolute zero — at room pressure and must be under 25 bar of pressure to crystallize. But when it finally does so, it assumes the thermodynamically most favored crystal structure: cubic closest-packing. In cubic closest-packing, a given atom is in contact with the maximum possible number of neighbors: 12 (6 in the same plane, 3 above the plane, and 3 below the plane). As such for sphere packing, it has the mathematically maximum efficiency of 74%.
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- I've researched more into the crystal structure of helium. D. G. Henshaw at the Chalk River Laboratories in Ontario did neutron defraction experiments in 1957 and determined helium has a hexagonal close-packed structure (Structure of Solid Helium by Neutron Diffraction, Physical Review Letters 109, Pg. 328 - 330 [Issue 2 – January 1958]) (abstract). Accordingly, I believe Web Elements’ helium crystal page is likely incorrect and they just chose the wrong illustration for the crystal sturcture. I've reverted the cyrstal structure back to simply "hexagonal close-packed". What I was really looking for was information on the density of solid helium. I've added this information to the article too (difference). Greg L 21:29, 4 March 2007 (UTC)
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[edit] The helium electron energy levels?
I couldn't find the helium electron energy levels in this article. Is there a standard space for them that i missed, in the Template:Elementbox or any other template? I found a website [1] that give the first five levels for standard He 2 4 as -54,4 eV, -13,6, -6,04, -3,4, -2,176. Maybe this can be added to the article.--JR, 12:46, 24 May 2007 (UTC)
[edit] precautions clarification request
in the precautions section, it is written "Containers of helium gas at 5 to 10 K should be handled...". Could somebody please clarify what the "K" means? I'm guessing it stands for kilo (k), but what are the actual units? 5 to 10k what? Is this pressure?
- An important clue to the meaning is the latter part of that same sentence you're reading, "...helium gas at less than 10 K is warmed to room temperature", which prettly clearly indicates that "10 K" is some below-room-temp temperature. The unit "K" is used conistently throughout the article to mean (and often linked to) the Kelvin temperature scale. DMacks 19:33, 29 May 2007 (UTC)
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- That makes a lot of sense. Thanks. (<-shaking morning cruft out of head)
[edit] "very nearly inert"
Helium (He) is a colorless, odorless, tasteless, non-toxic, nearly inert monatomic chemical element
Correct me if I'm wrong, but isn't He the most completely inert element? The rest of the noble gases are also inert, but the heavier they are the easier it is to coax them into compounds. Helium is the lightest and has only the first shell filled, thus is the least reactive element in the universe.
My point is that it's a little odd to call the least reactive element in the universe "nearly inert". By any sane measure, it IS inert. If we can't call helium inert (because of the existence of few rare unstable compounds), we can't call *anything* inert and we might as well ditch the word. --Lode Runner 10:25, 18 August 2007 (UTC)
[edit] Escape From Atmosphere
Creationist web sites such as this make the claim that "the amount of helium in the earth’s atmosphere indicates a young earth". It would be nice to get some information in this article about the escape rate of helium so that I have a place to redirect my creationist "friends" when they claim such nonsense.
Right now, the article merely says "an estimated 3.4 litres of helium per year are generated per cubic kilometer of the Earth's crust" and "the concentration of helium by volume is only 5.2 parts per million, largely because most helium in the Earth's atmosphere escapes into space due to its inertness and low mass", but neither of these claims is sourced.
If anybody knows this information, please add it. I would like to see the "Natural abundance" section expanded and made bulletproof. Bueller 007 09:51, 28 August 2007 (UTC)
- I just shuffled it around a bit. I found a whole wiki article about atmospheric escape and linked it there. Googling led me to this Science article, and especially footnotes 11, 12, 13 look relevant. I don't have access to those cited journals right now. A gentler introduction might be this web page. Whenever I'm confronted by creationist claims, I head over to TalkOrigins Archive to debunk them. They have a page debunking the helium claim, and its source happens to be the same as the Science footnote #12, so I think that's a good ref for loss (which apparently isn't solely due to low mass ("it's light so it floats up and out"). DMacks 14:56, 28 August 2007 (UTC)
- Thanks for the reply. I'm aware of all the talk-origins resources (I always go there first) but I find that t-o tends to go over the heads of creationists. For example, this is a reply to the creationist claim I mentioned above. [2] Good luck getting a creationist to sift through that. If it could all be boiled down to a couple of salient points for the Wiki article, it would be much more effective (and improve the Wiki'd knowledge about helium escape.) Bueller 007 15:42, 28 August 2007 (UTC)
- Yeah, it's a shame that science is verbose and technical, one of the appeals of "simple" (though wrong or incomplete or mis-generalized) statements. The abstract of the Lie-Svendsen & Rees article is a pretty layman's worded description of their conclusions. DMacks 15:49, 28 August 2007 (UTC)
- Thanks for the reply. I'm aware of all the talk-origins resources (I always go there first) but I find that t-o tends to go over the heads of creationists. For example, this is a reply to the creationist claim I mentioned above. [2] Good luck getting a creationist to sift through that. If it could all be boiled down to a couple of salient points for the Wiki article, it would be much more effective (and improve the Wiki'd knowledge about helium escape.) Bueller 007 15:42, 28 August 2007 (UTC)
[edit] Shortest lived isotope ambiguity
At present, the article claims "The shortest-lived isotope is helium-5 with a half-life of 7.6×10−22 second." Does this refer to the shortest lived of all isotopes? Or just the shortest lived of the helium isotopes? Stifynsemons 13:40, 3 September 2007 (UTC)
Answer: The article Isotopes of lithium has somewhat shorter half-lives for both lithium-4 and lithium-5. I will change the sentence you quote to read "The shortest-lived helium isotope ..." Dirac66 17:31, 3 September 2007 (UTC)
[edit] Link for buoyancy calculation
Note to user 141.52.232.84 When a link has been re-directed, please do not just revert without checking that the old link is still correct. In this case, the link for the buoyancy calculation (He vs. H2) was formerly directed to Airship where this calculation used to be. However several editors of Airship suggested that the calculation really belongs in Lighter than air, including one who deleted it from Airship a few days ago. Yesterday I reinserted the buoyancy calculation in Lighter than air as per these suggestions, and then I redirected the link in this (Helium) article so that it links to Lighter than air which is the new location of the calculation.
I am therefore reverting your edit to restore the new link. Apparently my first edit summary did not make the reason clear in the limited space allowed, so I am putting this longer explanation on the talk page. Please leave the new link alone now. Thank you. Dirac66 17:27, 9 November 2007 (UTC)
[edit] just wondering
isn't helium created by the splitting of a hydrogen atom , as opposed to fusion . —Preceding unsigned comment added by 70.53.125.49 (talk) 22:12, 27 December 2007 (UTC)
So, obviously, a hydrogen nucleus has two protons, and two electrons. Actually, it would have more than that, because it'd need to be split. Answer to your question: No. Pifreak94 (talk) 05:55, 29 December 2007 (UTC)
he —Preceding unsigned comment added by 68.144.180.195 (talk) 15:18, 20 January 2008 (UTC)
[edit] Uses of Helium - diving
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. —Preceding unsigned comment added by Rodgerclarke (talk • contribs) 09:59, 3 February 2008 (UTC)
- 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). [3] 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. SBHarris 10:15, 3 February 2008 (UTC)
[edit] Spammers
This page is being recked by spammers - I think we should go back to a point before vandalism and then lcok the page if possible. —Preceding unsigned comment added by Foxfoil (talk • contribs) 18:42, 5 February 2008 (UTC)
[edit] Applications has a double negative
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.)
75.181.46.158 (talk) 01:43, 24 February 2008 (UTC)
- 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. SBHarris 02:02, 24 February 2008 (UTC)
- Concurred (I am the second of now three different editors to make that wording change with comparable edit-summary). DMacks (talk) 05:39, 24 February 2008 (UTC)
- 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. Feline Hymnic (talk) 09:45, 24 February 2008 (UTC)
- Concurred (I am the second of now three different editors to make that wording change with comparable edit-summary). DMacks (talk) 05:39, 24 February 2008 (UTC)
- 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. —Preceding unsigned comment added by Fak119 (talk • contribs) 10:03, 25 February 2008 (UTC)
[edit] The picture of helium (and other gases)
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, Michał Sobkowski (talk) 08:35, 16 March 2008 (UTC)
[edit] Amount of Helium left?
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? KiwiTallGuy (talk) 10:21, 15 April 2008 (UTC)
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. Dirac66 (talk) 13:43, 15 April 2008 (UTC)
[edit] Liquid helium article
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. SpinningSpark 19:09, 15 April 2008 (UTC)
- 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. DMacks (talk) 20:53, 15 April 2008 (UTC)
[edit] language Use
Helium II state
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.
The correct term for this is Sublimation link http://en.wikipedia.org/wiki/Sublimation_%28chemistry%29 not evaperation —Preceding unsigned comment added by 67.58.208.247 (talk) 17:28, 2 May 2008 (UTC)
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.
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. Dirac66 (talk) 21:45, 2 May 2008 (UTC)
- How is an analogy "original research?" Inaccurate perhaps, but OR?! --Belg4mit (talk) 02:44, 4 May 2008 (UTC)
- 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. SpinningSpark 02:57, 4 May 2008 (UTC)
[edit] speach on helium[all you need to know on helium]
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.
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.
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). Most helium on earth is stored in the natural gas field in the US. In the modern universe almost all new helium is created as a result of the nuclear fusion in stars.
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) —Preceding unsigned comment added by Maddyson 961 (talk • contribs) 11:05, 20 May 2008 (UTC)
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. DMacks (talk) 14:31, 20 May 2008 (UTC)