Talk:Helium

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Archive 1:Oct 2002–Dec 2005

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] Natural Occurance?

Can some-one clarify if the sentence under Discoveries An oil drilling operation in Dexter, Kansas created a gas geyser in 1903 that contained 12% by volume of an unidentified gas. American chemists Hamilton Cady and David McFarland of the University of Kansas discovered it was helium contradicts the line further down under Production that says Thus the greatest concentrations (trace amounts up to 7% by volume) of helium on the planet are in natural gas fields. --Brother William 11 January 2006

It contained 12% of an unidentified gas but only 1.84% of the total was helium, so the remaining 10.16% must have been something else. -- Centrx 20:59, 4 June 2006 (UTC)

[edit] Is it true that....

By the year 2010 the earth will run out of helium gas? I heard somewhere and have been trying to prove or disprove it since. —The preceding unsigned comment was added by 67.97.145.132 (talk • contribs) 21:15, 26 January 2006.

The most significant market source of helium is natural gas fields, so it is unlikely helium will run out before natural gas does -- natural gas will not run out in 2010.Badocter 03:16, 24 June 2006 (UTC)

I don't think that the world will run out of helium by 2010 —The preceding unsigned comment was added by 81.77.215.33 (talk)

Helium is only present in viable quantities in some gas fields. There has been some concern about future supplies which might be worth mentioning in the article. I found some sources-[1] [2] [3] [4] 211.28.57.101 14:46, 17 December 2006 (UTC)

[edit] 65% of H

I believe that number is wrong.

The correct value might be, out of a wild guess, 0.618.

Can anyone confirm this?

--Cacumer 21:52, 31 January 2006 (UTC)

[edit] Helium flash

Currently, if you search for helium flash (astronomical) you are redirected to this site. Users who search for helium flash should not be redirected to this entry as this contains nothing on the subject. The status of a helium flash entry should be placed as "article not found". —The preceding unsigned comment was added by 207.233.90.1 (talk • contribs) 15:22, 1 March 2006.

I made it into a single sentence stub. Hopefully someone can expand it. (Feel free to do so yourself if you can!) Edgar181 15:40, 1 March 2006 (UTC)

[edit] Helium is the second most abundant?

The first sentence in the second paragraph states "Helium is the second most abundant and second lightest element in the periodic table". Abundant where? Other articles related to the elements I have read make a distinction between abundance on earth and abundance in the universe. On my first reading of this sentence I felt confused. The next sentence talks about the universe which helped to clarify the context but I still think the sentence I quoted is confusing. Since this was once a Featured articles I am not sure I should edit it. --Droll 03:20, 30 March 2006 (UTC)

I went ahead and did the edit based on information from the section on "Occurrence and production" later in the article. --Droll 04:43, 30 March 2006 (UTC)

Second most abundant in the universe. Hugo Dufort 08:15, 17 November 2006 (UTC)

[edit] Does it really remain liquid at absolute zero?

Hi, the article states that under normal pressure helium cannot be solid under whatever temperature, not even at absolute zero. That seems highly unlikely to me. I learned that absolute zero is when all molecules are motionless, so a compound at absolute zero MUST be solid, or am I very wrong? Caesarion 10:23, 4 April 2006 (UTC)

Absolute zero is a theoretical limit that can't be reached, there's always some energy left in real matter. The relevance of helium is that you may take away as much energy as you can (thus cooling it arbitrarily close towards absolute zero), it remains superfluid. Femto 11:35, 4 April 2006 (UTC)

Ok, that's about what I expected: its melting point is very close to absolute zero and can't be reached in any laboratory. Thanks a lot. Caesarion 12:01, 4 April 2006 (UTC)

Nonono, there is no solid state to reach, even as a theoretical limit. You just run into some weird quantum effects long before the energy gets low enough to allow the formation of a neat crystal lattice. Femto 14:02, 4 April 2006 (UTC)

Well, this goes slightly beyond my knowledge/imagination/whatever. Let me think a little... you reach something you can't call liquid but isn't solid either and does not obey the laws of classical mechanics but can only be explained in quantum mechanics... I think this should be mentioned/clarified in the article, for I've been curious about this for a long time. Caesarion 21:30, 4 April 2006 (UTC)

This may help. Absolute zero is NOT the temp at which atoms are motionless. If they sat still they would violate the uncertainty principle, which says that things cannot be perfectly localized in space (due to their wavelike nature, essentially). As their energy and specifically their momentum drops, their spacial extent as wave-packets broadens. Even at absolute zero all atoms have a zero-point energy which is the residual kinetic energy that cannot be removed as heat, and exists as an undertainty in their momenta due to their uncertainty in location in space, again due to their wave nature. For most elements, the bonding energy between atoms is enough to "pin" the individual atoms (location of their nuclei) to locations smaller than their "size" (how big their electron cloud is). However, at really cold temperatures, atoms which bond poorly find themselves with waves that overlap. If the Pauli principle doesn't prohibit it, all these waves just cohere into one condensate, and the location of the individual atoms no longer has meaning. This stuff is not a solid. It's a fluid, and specifically a superfluid (there is no friction because there are individual particle to slide past and interact with each other). That's what happens in cold helium. S B H arris 19:18, 17 December 2006 (UTC)

[edit] Helium as cognate to "Sun"

The article notes that the Greek "helios" is 'surprisingly' cognate to the English word "Sun". I'm not sure about 'surprisingly'--Helios was the Greek god of the Sun, and isn't the element named after him since it was first observed in a solar spectral line? I'm not sure this line explains the naming of the element at all, since it looks like the correspondence is coincidental rather than deliberate. 128.104.161.17 17:37, 19 April 2006 (UTC)

It thought that was odd too, so took it out. --mav 15:56, 21 May 2006 (UTC)

[edit] Neutron number

Anyone kind enough to make the "He is stable with 1 neutronS" singular? --Starryboy 18:35, 27 April 2006 (UTC)

Never bothered me, but substed and changed. Femto 19:07, 27 April 2006 (UTC)

[edit] Spin sentence

Taken from article:

Depending on the spin orientation of the two electrons in the helium atom, one speaks of parahelium for two anti-parallel spins (S=0) and of orthohelium for two parallel spins (S=1). For the orthohelium one of the electrons does not sit in the ground orbital (1s). [5] —The preceding unsigned comment was added by Maveric149 (talk • contribs) 16:05, 21 May 2006.

I'm not sure where this should go. It was in its own stub section, but that can't stand by itself... --mav 16:05, 21 May 2006 (UTC)

[edit] Abundance and Production

What is the reason for combining these two sections as subsections in an empty supersection? Why is it not reasonable to cleanly divide it into natural abundance and occurence, and artificial production? It does not make sense to explain the cause of natural abundance in the crust in the same section that talks about the extraction of the retrieval from natural gas, and laboratory synthesis of the element (and note that this radioactive explanation repeats what is explained more fully in the Abundance section above). Please do not revert, and totally at that, simply because the sections and text look different than before. - Centrx 18:38, 21 May 2006 (UTC)

Because they are closely related sections ; abundance in the real world leads to the ability of humans to extract that abundance for their use. Per WikiProject Elements convention, those two aspects would be treated directly under an ==Occurrence== section, but here, there is enough text to subdivide that section into two subsections. --mav 13:11, 22 May 2006 (UTC)

[edit] The Introduction

Reason given by User:Maveric149 in edit summary: "see Wikipedia:Lead section ; the lead needs to be a concise encyclopedia article in its own right ; also part of FA stnadards ; this is also the lead that passed FAC"

First of all, this article became featured more than two years ago and standards have certainly changed since then. Still, when the featured tag was added to the Talk page on March 15, 2004, the introduction was in fact short and to the point. The same is true when the article was featured on the Main Page on May 31, 2004.

The shorter introduction is a concise article in its own right. It does, as the Featured article criteria also state, "summarize the entire topic". If there is some deficiency that it should cover but does not, then that deficiency can be remedied without reverting the entire introduction to a previous state. Note also that Featured article criteria states that the lead summary "prepares the reader for the higher level of detail in the subsequent sections" (emphasis added). How are fractional distillation, a general method, and the specific maximum concentration, both tangents to the main point about the source as natural gas, appropriate for the introduction? There are numerous other unnecessary particulars that are not appropriate for the introduction. Why are the introductions for United States and New York City both shorter than your introduction here, when both articles are twice as long as this one?

The reasons you have given actually indicate that the shorter introduction should be used. Please provide some good reasons why it shouldn't be. Also, what is not in the shorter introduction but should be, and why can it not be added to the shorter introduction. —Centrx→talk 21:26, 13 June 2006 (UTC)

Again, see wikipedia:lead section. The shorter version says nothing of the history of the element, nothing about how most of it is formed, does not mention how it is extracted, and also fails to mention anything about a quality of the gas that most people are familiar with (the voice-changing part). Without that, the lead can't stand alone as a concise version of this article. FA standards have increased a great deal since this article was first listed as Brilliant Prose so I and others completely rewrote it and put it through a proper FAC instead of de-featuring it. The lead section that passed that is almost identical to the one now in the article. So please, improve the wording and fix any error but do not cut. --mav 03:38, 14 June 2006 (UTC)

Done, [6]. —Centrx→talk • 20:41, 5 July 2006 (UTC)

[edit] Helium in the perdiodic table

This is just temporary, I will delete this section once I have the answer

I got told that all the materials in group 8 (or 18 if we count the transition metals) have 8 electrons in their outer shell (except once past Argon). So why is Helium in group 8 (or 18) and not in group 2? It has only 2 electrons in its outer shell.

--Josellis 11:37, 10 July 2006 (UTC)

First off, we don't remove info in talk pages; this should be kept as an archive. As for helium, it is a noble gas, like neon. Group 2 is the alkaline earth metals, like beryllium. Georgia guy 15:53, 10 July 2006 (UTC)

A more accurate description of group 18 would be that the outermost shell is full. The first energy level has only the s orbital, with space for two electrons. So, for helium, its two electrons fill the outermost shell. Elements with more protons than helium go into higher energy levels with both the s orbital and the p orbital, and therefore 8 electrons in the outermost shell. —Centrx→talk • 07:07, 11 July 2006 (UTC)

[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)

For the whole universe, the average is one atom of helium per 64 cubic centimeters of space. For hydrogen, about 1 atom in 4 cc. S B H arris 04:53, 17 January 2007 (UTC)

[edit] Treated like liquid He.

"Containers of helium gas at 5 to 10 K should be treated as if they have liquid helium inside" Treated how? --Gbleem 03:21, 12 September 2006 (UTC)

That likely means to use the same safety precautions one would use for a container of the liquid. The liquid is more hazardous than the gas (rapid increase in gas volume comes to mind). Like how you would probably treat a jar from rat poison as if it had rat poison in it (i.e., not use it as a drinking glass) even after you think you dumped the poison out. DMacks 05:08, 12 September 2006 (UTC)

[edit] Grade A

"By 1949 commercial quantities of Grade A 99.995% helium were available." Do they really call it Grade A? --Gbleem 03:24, 12 September 2006 (UTC)

Yes, they do. --Gbleem 03:27, 12 September 2006 (UTC)

I reverted until I or someone else can find more info. --Gbleem 04:41, 12 September 2006 (UTC)

Helium is sold in grades of purity.[7]

Type I, gaseous

Grade A
Grade F
Grade J

Type II, liquid

Grade A
Grade F

The abstract of that ISO document sounds like those type and grade specifications are applicable to certain uses only, not a general-purpose terminology. DMacks 05:03, 12 September 2006 (UTC)

[edit] Helium Voice misconception stuff

Hi,

It is a common misconception that Helium's effects on the voice are related to its density. The real explanation is slightly more complicated. Because Helium is monoatomic (earth's atmosphere consists of over 95% diatomic molecules), its adiabatic index differs from that of air. This means that the speed of sound in helium is faster, and sound of the same frequency has a longer wavelength compared to in air.

It looks like the "common misconception" is more correct than the article. The speed of sound $c=\sqrt{\gamma\frac{RT}{\mu}}$ depends on both adiabatic index $γ$ as well as on the molecular weight $μ$ . The adiabatic index for helium differs from that for air by a factor of 25/21, while the molecular weight ratio is 4/30.

--Melnikovsky 15:11, 21 October 2006 (UTC)

This was recently added. I have deleted it. —Centrx→talk • 23:56, 27 October 2006 (UTC)

I've changed the fundamental frequency stuff to better match the listed references and this reference. johnpseudo 21:24, 21 November 2006 (UTC)

- - - Begin amendment by Jon Kroger *****

I would guess that the voice change is the result of helium's effect on muscle, specifically vocal cord muscles. It is plausible that helium constricts and tightens the vocal cord muscles and therefore creates a higher pitch sound.

- - - End amendment by Jon Kroger *****

Has nothing to do with muscles. The pitch of a flute or whistle in helium is higher than in air also. Anybody who has valved helium from a tank knows this. It's strictly a speed of sound issue, as noted above. Mostly this is due to molecular weight, but monatomic gases do have slightly higher sound speeds than diatomics (by a factor of 9%), even at the same molecular weight. An effect relatively unimportant with these large density differences. However, helium will give an even higher pitch than deuterium for this reason. S B H arris 03:16, 13 December 2006 (UTC)

[edit] Reactivity

Under the sentence, "Helium is the most unreactive element of group 18," it should be noted that this makes helium the most unreactive of all the chemical elements. I'd also note this in the introduction. I'd do it myself, but for some reason the article is protected.--The Sultan of Surreal. 02:37, 2 November 2006 (UTC)

The old protection has been lifted. Edit away! Femto 15:30, 2 November 2006 (UTC)

I wonder how do you measure reactivity? I mean -- does an experiment exist, which proves that Helium is more unreactive than Neon?--Melnikovsky 14:32, 19 November 2006 (UTC)

Helium's first ionization energy is the highest of the whole periodic table, and by much. http://www.800mainstreet.com/4/0004-000-IE.GIF Thus, it is hard to make it throw away, or even share, an electron. Now since its outermost orbital is full, it can't accept an electron neither. So basically it can't really react with other elements and form molecules under normal "molecular" conditions (although some molecules created in a high-energy environment or a plasma can theoritically contain Helium, such as HHeF). Hugo Dufort 05:34, 20 November 2006 (UTC)

[edit] Dihelium?

There's a sentence in Helium#Gas_and_plasma_phases that suggests that the neutral He₂ molecule exists. Isn't this forbidden by molecular orbital theory? youngvalter 05:26, 21 November 2006 (UTC)

It is impossible in a normal gas, but in a plasma "everything goes" since the formidable energies involved are many times higher than any ionization energy! The Helium nucleus gets stripped of its electrons and floats around as ionized gas, forming "unnatural" bonds with some of the other molecules. Hugo Dufort 07:03, 21 November 2006 (UTC)

[edit] Radiation in Helium

As quoted in your description of Helium you state"On Earth, helium is primarily a product of the radioactive decay of much heavier elements, which emit helium nuclei called alpha particles; it is found in significant amounts only in natural gas, from which it is extracted at low temperatures by fractional distillation". I have a question on that subject. Does Helium retain any Radiation after processing? As a deep sea diver we breath up to 98% Helium at deeper depths in saturation diving and our cells get saturated with the element. I would like any info on this matter that you can supply.

Thank you

No, most helium is derived from radiation (a helium baloon or a diver's cylinder is basically a container of retired alpha particles), but no radiation is left. Zip. You get far more radiation from the potassium-40 in your cells and carbon-14 in your tissues. And as for danger, saturation diving beats most things! S B H arris 03:30, 13 December 2006 (UTC)

[edit] History of the periodic table

One form of Mendeleev's periodic table, from the 1st English edition of his textbook (1891, based on the Russian 5th edition)

When was helium identified as the element with atomic number 2 in the periodic table of elements?

This periodic table from 1891 (Image:Mendeleev Table 5th II.jpg) does not list helium, nor does it leave an empty slot for element number 2. The result is that all elements beyond hydrogen are given an "atomic number" one less than the number of protons. -- Petri Krohn 02:26, 29 November 2006 (UTC)

In fact the table is missing all noble gases, so there are other gaps in the table. Question number #2 is thus:

When were the noble gases added to the periodic table?

-- Petri Krohn 03:07, 29 November 2006 (UTC)

(Moving discussion to Talk:History of the periodic table)

[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] I Love Victy??

Please restore this page to a previous state and flag it as protected.

[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)

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)

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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