Talk:Xenon

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Contents

[edit] Information Sources

Some of the text in this entry was rewritten from Los Alamos National Laboratory - Xenon. Additional text was taken directly from USGS Periodic Table - Xenon, from the Elements database 20001107 (via dict.org), Webster's Revised Unabridged Dictionary (1913) (via dict.org) and WordNet (r) 1.7 (via dict.org). Data for the table was obtained from the sources listed on the main page and Wikipedia:WikiProject Elements but was reformatted and converted into SI units.

[edit] Talk

I'm surprised that this article makes no mention of Xe-135 poisoning in fission reactors. Xe-135, one of the transient products of U-235 fission, does an extremely good job of absorbing the neutrons needed to sustain a fission reaction. Working around this is an important factor in reactor design and operation.

But my nuclear engineering knowledge is a little too rusty for me to be a really definitive source here... The effect is mentioned in: http://www.physicstoday.com/vol-55/iss-10/p42.html

____________________________

Probably because it is too specific a nuclear reactor issue.

[edit] Fission discussion

I am not sure why the section on fission was written in that way. I just had to change it - first, the article mentioned Xe-131, and other isotopes are produced from fission of U-238 and Pu-244. While that is true, they are produced, the "important" fissile materials are really U-235 and Pu-239, and the "important" xenons produced are the radioactive Xe-131m, Xe-133, Xe-133m, and Xe-135.

[edit] Hyperpolarized Xe

Actually, hyperpolarized xenon can be used for NMR spectroscopy as well as MRI. Literature abounds.

[edit] Hanging upside down

A complicating danger is that xenon is heavier than air, and in fact too heavy for the lungs to expel unassisted.

I encountered this chastisement several times when reading about xenon inhalation. I believe it is a myth with no proof behind it. To quote Steven B. Harris, M.D. on sci.physics :

Sorry, but this is incorrect. The forces of mixing caused by gas inhalation and exhalation in normal lungs are HUGE. More than enough to stir up any mix of mere gases, even when one is 5 times heavier than air, as in SF6. Heck, I've done fluoroscopy of living dogs being ventilated with oxygen while their lungs were full of *liquid fluorocarbon,* which has twice the density of water, and several thousand times the density of air. The mixing is still excellent, and the bubble jets get all the way to the ends of the airways with every breath (and the dogs are fine). An inert gas like xenon will simply be mixed up and purged in a breath or two (xenon has been successfully used as a gas anaesthetic). If it has enough concentration to produce an anaesthetic effect before then, you'll feel it. And you can always asphyxiate yourself with it. But on the whole, xenon is no more, and no less dangerous than nitrous oxide.

If you think about it, our lungs would pool with heavier CO2, and much heavier water vapour, if they were that weak. I think the advice about bending over should be reworded to indicate it is a common misbelief. A problem arises though. Do we strive for accuracy, or to keep people ignorantly safe? Splarka 09:09, 10 Apr 2005 (UTC)

Accuracy. --Andrew 09:37, Apr 10, 2005 (UTC)
Water vapor is not heavier than oxygen or nitrogen (MW 18 versus 32 and 28 respectively). CO2 (MW 44) is heavier than O2 and N2, but not by a huge amount. Xe is considerably heavier than any of these at MW 131, however, as has been stated by others, the mixing in the lungs is good enough to expel it. Xe is similar to the other noble gases in that it is a simple asphyxiant. Xe and the other noble gases are not similar to Nitrous Oxide.Badocter 17:19, 1 July 2006 (UTC)
Xenon is not just a simple asphyxiant. It is a more powerful anesthetic than N2O (MAC of 0.6 to 0.7 vs 1.0 for N20: see [1]) and would certainly behave that way if you inhaled it-- i.e., would cause immediate dizzyness and narcosis at 30% concentration at sea level, whereas other inert gases like argon at 50% would merely reduce oxygen concentration to that at 9,000 ft, which most people not doing exertion would tolerate without any symptoms at all. SBHarris 00:07, 12 October 2007 (UTC)
Unfortunately I don't think a message in a Usenet archive provides a suitable reference for this myth. I'm not 100% sure, but I think an article such as this might (by way of analogy with inhaling sulfur hexafluoride.) If the lungs couldn't expel the SF6, then surely they would fill up and exclude the O2? Unfortunately I can't read medical jargon. — RJH (talk) 05:02, 13 October 2007 (UTC)
I'm sure we can find sources to prove that the myth is wrong. But are there any "reliable sources" that show that the myth is worth mentioning in the first place? I don't think we need to discuss every myth that circulates in Usenet, mailing lists, or in web forums. Is there any secondary secondary source discussing the myth itself? (Such as an educational journal, popular magazine, or snopes.com article at least?) --Itub 07:44, 13 October 2007 (UTC)
Yes I agree. That at least one person believes the myth is apparent in the final paragraph here: http://sciencemole.wordpress.com/2007/05/12/why-does-helium-make-your-voice-squeaky/ But it doesn't appear to have any widespread notability that I could find. — RJH (talk) 16:59, 13 October 2007 (UTC)

[edit] Isotope error?

How can Xe-136 decay to Ba-136 by beta decay when the atomic number of barium is 2 higher? Should that be double beta decay or something similar? Ken Arromdee 03:34, 26 September 2005 (UTC)

I cant' find a source to verify what it is as all the sources I can find say Xe136 is a stable isotope.[2] With a half life of 200000000000000000000 years that is stated in the current version of this article, less than 1 part per billion of this stuff would have disappeared from a sample in the time that has elapsed since the big bang happened.Badocter 17:47, 1 July 2006 (UTC)
The sources at talk:isotopes of xenon all set a lower limit, at some 10^21 a. Femto 13:14, 2 July 2006 (UTC)

[edit] Depletion

Deleted concern about depleting Xenon. The total atmosphere mass is 5.1480 x 1018 kg. If Xenon is one part per 20 million (by weight?), then there is 250 billion kilograms of Xenon in the air. More if the concentration is by volume. pstudier 23:41, 25 February 2006 (UTC)

[edit] Metallic Xenon

From the current article: "Using tens of gigapascals of pressure, metallic xenon has been made" I can not find a source for metallic xenon. I have found several citable sources for xenon-metal cmplexes with gold and mercury -- perhaps that was what was meant in the article. I have not found information for synthesis methods of these compoundsBadocter 08:24, 2 July 2006 (UTC)

I added a reference, and slightly reworded the sentence. The reference is in relation to using high pressure diamond anvils to force xenon into metallic crystalline phases. They were actually hoping that it would form a compound with iron they also had in the press, but, it didn't. Phidauex 17:09, 11 July 2006 (UTC)

[edit] GA nomination

Some things I think are wrong with this article:

  • The lead section is far too short. According to WP:LEAD, the lead section should be able to stand alone as a concise overview of the topic (see WP:LEAD).
  • The fourth reference just says "Link".
  • The History and Occurance sections could do with expansion.
  • Applications could be expanded considerably, replacing bullet points with subsections. Unless there are wikipedia articles already concerning those applications, that is. This won't stop it becoming a GA but it will stand in the way of FA status.
  • The article definitely needs more references for everything.

 -- Run!  09:17, 17 July 2006 (UTC)

[edit] GA Failed

This is very near GA, but it's terribly undercited, and needs at least one reference (that covers all information therein) for every paragraph. It's not a bad fail, though - everything else is fine - so poke me on my talk page when you've fixed it up. Adam Cuerden talk 13:42, 27 February 2007 (UTC)


[edit] Information on Xenon as an anesthetic

As an anesthetic, Xenon is said to be an almost ideal agent. Xenon is a colorless, odorless gas that causes no irritation to the user. It is non-toxic, and has proven to be hypoallergenic. By having low blood-gas coefficients, which is the gaseous equivalent of solubility, the effects of xenon are rather rapid. It can produce unconsciousness, analgesia (pain-kill), and muscle relaxation. It does not cause any profound respiratory depression, and is cardiac stable. "Xenon anesthesia produces the highest regional blood flow in the brain, liver, kidney and intestine." This means that the heart and brain are not put under any excessive strain. Since it is a noble gas, and as such requires extreme conditions to react with other elements, it is not metabolized in the body. This means that it is not changed when used and is thus reusable – it can be used to achieve the initial effect. The xenon one inhales is identical to the xenon which one exhales, and it is easy to store since it is stable and nonflammable.

information can be readily found on google. thoughts on adding this as a section? Anonymous

[edit] Over 80 compounds

Hi. Is there an original reference for the statement that "However, xenon can be oxidized by powerful oxidizing agents, and at least 80 compounds of this noble gas have been synthesized"? It seems to be a frequently repeated fact, but I can't locate the original source. The online CRC Handbook only showed 17 compounds, but perhaps more have since been added. Possibly a well-referenced "List of xenon compounds" page is the only way to satisfactorily provide the citation? — RJH (talk) 22:39, 27 September 2007 (UTC)

This article from 1974 already has a table with over 80 compounds: Moody, G. J., A Decade of Xenon Chemistry. J. Chem. Ed. 1974, 51, 628-630.PDF (subscription required). A recent review doesn't give an exact number for Xe compounds, but it mentions that "close to a hundred organoxenon, Xe–N and Xe–Cl compounds are known up to date" and that "about half a thousand compounds of Ng's have been synthesized since 1962". (Wojciech Grochala. Atypical compounds of gases, which have been called noble. Chem. Soc. Rev., 2007, 36, 1632-1655, doi:10.1039/b702109g). Finally, a quick search on SciFinder Scholar for structures containing Xe yields over 2000 results! This number can be considered an overestimation, but I don't know by how much, because it can include "extras" such as isotopologues and compounds that haven't been characterized experimentally. --Itub 16:55, 12 October 2007 (UTC)
Thank you. — RJH (talk) 04:40, 13 October 2007 (UTC)

[edit] Endings of inert gases, from the Greek

Okay, time for the ancient Greek lesson. The ending -ος (os) in Greek is used for nomnative masculine singular adjectives, which are used to modify masculine singular nouns, such as a man. Thus, argos, neos, kyptos, and xenos would refer to a lazy (or slow or inactive) man, a new man, a hidden man, and a stange man, respectively. When the ending of such an adjective is changed to -oν, that signifies the advective is now singular neuter, to be used to modify neuter nouns, like things [3]. In Greek, as in any well-inflected language (Spanish, say), if you talk about "the new, the lazy, the hidden, and the strange" without specifying the noun, it is inferred from the adjectival ending, and in which (as in English) an adjective used like a noun where the noun isn't given, becomes a noun (the noun is implied). In English you can't tell if men, women, or things, are being referred to in adjectival nouns, but in Spanish or Greek, it's clear from the ending what class of noun is meant or implied.

Now, in the original paper on the discovery of argon in 1895, the discoverers are at pains to note that they have used the ending -oν and thereby intend that "argon" refer to the laziness of a THING (of course, it's a chemical, not a person). And άργόν(argon) is a perfectly good Greek word (though an article, like "the" as in τόν άργόν, would usually be included when it is used as a noun). But argon is no more "from" argos than señorita is "from" señor. Yes, I know that dictionaries commonly suggest that non masculine words are derived "from" the masculine form (which in this case refers to a person, not a chemical), but that is a mere dictionary convention for listing the masculine gender first, in lists of endings of adjectives and nouns in a declension. If you want to know what foreign word used for a new thing really refers to, and is intended to refer to, you need to see the authors and discoverers as the last authority. In all these cases of inert gases, following the discussion of argon in the original scientific paper (which is available on JSTOR), the όν ending should be used as the primary Greek reference, not -ος. I don't care what the dictionaries say: the dictionaries didn't discover the gases. The people who did discover them, don't give same derivation the dictionaries give. They simply use the adjectives properly and automatically, as the better Greek scholars that (in those days) they were. SBHarris 00:59, 12 October 2007 (UTC)

Could you say which paper exactly (and in which page) shows that "discoverers are at pains to note that they have used the ending -oν"? I've been looking at Philosophical Transactions of the Royal Society of London. A, Vol. 186. (1895), pp. 187-241, but I haven't been able to find what you refer to (I haven't read the whole article yet). Is this the article you refer to? --Itub 08:14, 12 October 2007 (UTC)
This is the discoverers of argon: Lord Rayleigh; William Ramsay (1894 - 1895). "Argon, a New Constituent of the Atmosphere.". Proceedings of the Royal Society of London 57 (1): 265-287. Xenon, neon, and kypton are named by analogy, by the same Ramsay, and his new research partner Travers. SBHarris 21:03, 12 October 2007 (UTC)
The 1904 edition of "The New International Encyclopædia" on Google books lists: XENON (Gk. ξένον, neu. sg. of ξένος, xenos, foreign, strange, host). I guess "neu. sg." means "neuter singular"? Would an extended explanation like this be satisfactory? "from the Greek ξένον, neuter singular of ξένος, xenos, meaning foreign, strange, host".
  • Anonymous (1904). in Daniel Coit Gilman, Harry Thurston Peck, Frank Moore Colby: The New International Encyclopædia. Dodd, Mead and Company, p. 906. 

[edit] Good Article Nominee

This article's Good Article promotion has been put on hold. During review, some issues were discovered that can be resolved without a major re-write. This is how the article, as of October 16, 2007, compares against the six good article criteria:

1. Well written: Some editions need here to be boarded by the manual of the style.

This enigmatic statement leaves me wondering what to do. I have tried to follow the MoS as I understand it, so perhaps you could clarify with details? — RJH (talk) 14:39, 18 October 2007 (UTC)

in comparison to hydrogen and uranium, this article will be a GA soon.

2. Broad in coverage: The article is well broad in coverage.

I regard this article as satisfying your issue here. The expansion was meant to address the previous GA review, and I'm unclear why you consider the content to be insufficiently brief. (Please compare to the FA status articles hydrogen and uranium.) Perhaps you could clarify? — RJH (talk) 14:39, 18 October 2007 (UTC)

3. Neutral point of view: The article counts on a very good neutral point of view.

4. Stability of the article? Not the subject of any recent or on-going edit wars.

5. Images: The deficiency of images is not a step/criteria of fall. Anyway, the images have a very good quality.

Please address these matters soon and then leave a note below showing how they have been resolved. After 48 hours the article should be reviewed again. If these issues are not addressed within 7 days, the article may be failed without further notice. Thank you for your work so far. Macys123 21:44, 17 October 2007 (UTC)

I am glad to report that this article nomination for good article status has been promoted. Macys123 18:24, 21 October 2007 (UTC)

Thank you. — RJH (talk) 18:40, 21 October 2007 (UTC)

[edit] veropedia

Just wanted to say: This is a really good article, so I uploaded it over on Veropedia - basically, a Wikipedia mirror that attempts to collect the best-researched Wikipedia articles, and then get experts to review them. Great work on it =) Adam Cuerden talk 06:56, 24 October 2007 (UTC)

[edit] Radioxenon releases compared to radon-222

The article contained a statement that the concentration of radioxenon releases by nuclear reactors is small compared to naturally occurring radon-222. This statement was justified with the following footnote (reformatted here):

A typical boiling-water nuclear reactor releases about 13,000 Ci of 133Xe per year. (Stein, L. (1973). "Removal of Xenon and Radon from Contaminated Atmospheres with Dioxygenyl Hexafluoroantimonate, O2SbF6". Nature 243: 30–32. ) In a typical indoor environment, radon concentration is about 200 pCi/L. (Staff (June 16, 2005). Radon in Buildings. Canadian Centre for Occupational Health & Safety. Retrieved on 2007-10-13.) Thus an equivalent level of radioactivity from radon-222 would occupy:

\begin{smallmatrix} \frac{1.3 \times 10^4 \text{Ci}}{2.0 \times 10^{-10} \text{Ci/L}} = 6.5 \times 10^{14} L \end{smallmatrix}
or only 650 km3. Compare, for example, to the surface area of the Earth, 5×108 km2, while looking at the first kilometer thickness of the atmosphere.

I have removed the statement as its purported justification is unacceptable, for a number of reasons:

  1. The figure of 13,000 curies per year, taken from the Nature paper, is a 1970s estimate from the U.S. Public Health Service for a typical boiling water reactor. It says nothing about emissions from other reactor designs, or emissions outside the United States.
    True, but I only wanted a ball-park figure. -RJH (talk) 16:10, 9 November 2007 (UTC)
  2. The figure of 200 pCi/L of radon is not a typical indoor concentration, but is merely a re-expression of the Working Level (WL), a reference point for radon and radon daughter levels. Normal concentrations are much lower. The CCOHS web page cited, for example, states that in a 1980 survey, most (>88%) of Canadian private houses checked had radon levels of 0.02 WL (approximately equivalent to 4 pCi/L of radon) or below. A quoted average for single-family homes in the United States is 1.3 pCi/L [4].
  3. Most importantly, the computation itself is meaningless.
(a) The emission rate of 13,000 Ci/yr is multiplied by 1 yr to obtain a total of 13,000 Ci. As the choice of 1 year was arbitrary, this figure is meaningless. The total amount of any radioisotope released by a reactor present in the environment will depend on the half-life of the radioisotope and the length of time the reactor has been operating, as well as the release rate.
Fine, use 100 years. -RJH (talk) 16:10, 9 November 2007 (UTC)
Assuming a constant release rate and a long period of operation, you should use the mean lifetime, τ, of the radioisotope, since \int_0^\infty e^{-t/\tau} dt = \tau. Spacepotato 22:00, 9 November 2007 (UTC)
I guess that's so. For an isotope with a ~9h half-life it's not going to stick around too long. — RJH (talk) 13:57, 10 November 2007 (UTC)
(b) Released effluent gases will not instantaneously diffuse themselves throughout the Earth's atmosphere. Rather, theywill mix with the local ambient atmosphere more or less rapidly, depending on local winds, weather conditions, etc. Therefore, comparing radioxenon release to the volume of the Earth's atmosphere as a whole is likewise meaningless.
Spacepotato 22:28, 8 November 2007 (UTC)
The original quote was comparing average densities across the planet. It was not attempting to compare localized densities. Your objection is too tactical. -RJH (talk) 16:10, 9 November 2007 (UTC)
I don't think so. The natural reading of the statement is that it's talking about local concentrations, especially since it immediately followed a statement talking about high concentrations of radioxenon emanating from nuclear reactors. Spacepotato 22:00, 9 November 2007 (UTC)

The original statement about radon-222 was provided uncited. I was attempting to provide a sufficient citation, and had a difficult time doing so as you can tell. -RJH (talk) 16:12, 9 November 2007 (UTC)

It's better to use existing measurements of radioxenon levels. For sample measurements, see e.g. Low-level radioxenon measurements for Comprehensive Nuclear-Test-Ban Treaty verification purposes, talk by Paul Saey, 15 May 2007, Automated radioxenon monitoring for the comprehensive nuclear-test-ban treaty in two distinctive locations: Ottawa and Tahiti, T. J. Stocki, et al., Journal of Environmental Radioactivity 80, #3 (2005), pp. 305–326. By the way, the statement was added in this edit by an anonymous IP address at the U.S. Department of Energy. Spacepotato 22:25, 9 November 2007 (UTC)

[edit] Needs information on spectral properties

Much of this article's content refers to the emission of light by ionized xenon, yet the article contains no information on the actual emission spectrum, other than saying xenon's emissions approximate a blackbody curve similar to sunlight. No mention of the fact that xenon also emits in the ultraviolet and broadband infrared.

It would be useful to see a blackbody curve superimposed over the xenon emission curve, and it would also be useful to see the emissions beyond the visible spectrum. I'm surprised that a featured article lacks key information like this. -Amatulic (talk) 00:33, 8 December 2007 (UTC)

CRC lists about 300 emission lines for Xe with intensities along with annotations to indicate if a line is wide or nebulous or shaded and so on. Putting this into graphical form with, say, 6000K blackbody emission superimposed would be not only a lot of work, but also difficult. This is because it is not just the intensity of each line that is significant, but also the density of the lines along the wavelength axis. To be able to compare the Xe's emission spectrum to the blackbody spectrum, the preparer of the graphic would have to integrate the intensity of the lines with their density to resolve an average intensity in each wavelength region. Karl Hahn (T) (C) 14:35, 8 December 2007 (UTC)
It could be useful to have emission/absorption line images for all the elements, such as the selection shown here. I'm not sure how we could obtain them, however, unless there's a free app. we could use or if somebody has a lab with a spectroscope and a camera handy. — RJH (talk) 16:14, 8 December 2007 (UTC)

[edit] Use of Xenon in Double and Triple Glazing

Replacing the air in the spaces between the sheets of glass in sealed multiple glazing units with a heavier gas increases the thermal insulation. Argon is the cheapest and the most common replacement gas but the heavier the gas the better and a small number of units are sold filled with Xenon. The insulation is measured by its U value (w/m²K), the lower the better. A plain glass, air filled, double glazing will have a U value of about 3. A Xenon filled triple unit with coated glass can have a U value as low as 0.4. At this level, averaged over the year a building is likely to gain more thermal energy through the window via the greenhouse effect than is lost through the window. Nick Rouse (talk) 00:52, 5 January 2008 (UTC)

Do you have a source that could be cited?—RJH (talk) 23:13, 11 January 2008 (UTC)
And (for my own information), why in the world would anybody use Xe when they could be using sulfur hexafluoride, which is 11% heavier in molecular weight, and in practice about 6% denser? That use isn't listed on the SF6 wiki, but probably should be, since it has been done.SBHarris 00:00, 12 January 2008 (UTC)

According to p. 56 of Solar Energy: The State of the Art: ISES Position Papers (ISBN 1902916239), conduction accounts for the bulk of heat transfer through double-glazed windows, and according to the Air Liquide website, SF6 has a thermal conductivity of 12.058 mW/(m K) at 1 atm and 0 °C, as opposed to 5.192 mW/(m K) for xenon. So, SF6 appears to be worse than xenon as a window fill gas. Spacepotato (talk) 02:10, 12 January 2008 (UTC)

[edit] Amount of electricity to produce doesn't sound reasonable

The article claims: "Extraction of a liter of xenon from the atmosphere requires 220 watt-hours of energy." (footnote 38).

I think this should be kilowatt-hours, not watt-hours. 220 watt-hours would cost only about US$ 0.01. If that were true, it would be an insignificant part of the cost, and so not worth talking about. 220 KWH would cost about US$10, matching the purchase costs cited a few sentences later. Does anyone have any better sources than footnote 38?

PatMcGee (talk) 03:20, 8 February 2008 (UTC)

That is a good point, and the source doesn't seem to be the most reliable for this type of data. The best I've been able to find is 540 kwh per liter of xenon. This is just from the tiny text extract from a Google scholar result, because I can't access the original article to read all the context. --Itub (talk) 11:22, 8 February 2008 (UTC)
The following paper also lists 200 watt-hours:
Goto, Takahisa; Nakata, Yoshinori; Morita, Shigeho (2003). "Will Xenon Be a Stranger or a Friend?: The Cost, Benefit, and Future of Xenon Anesthesia.". Anesthesiology 98 (1): 1-2. 
It is citing:
Schucht F: Production of anaesthetic gases and environment. Appl Cardiopulm Pathophysiol 2000; 9: 154-5
as the source, but unfortunately I don't have access to the latter. Perhaps this is an oft-repeated error?—RJH (talk) 18:55, 8 February 2008 (UTC)

[edit] "Colorless gas" image

I propose removing the current image:Xe,54.jpg from the infobox. It adds nothing to convey a "colorless" attribute; the predominant color in that image is of the container and the background. Vials.jpg would do a much better job of showing that xenon gas is as colorless as ordinary air. Wdfarmer (talk) 05:36, 10 February 2008 (UTC)

I agree. I came here to say the same thing. --P3d0 (talk) 13:00, 10 February 2008 (UTC)
Done. Ziros (talk) 02:53, 13 February 2008 (UTC)
Aren't those vials unstoppered? So that would make them full of ordinary air. =)—RJH (talk) 16:33, 13 February 2008 (UTC)

[edit] Electrons....

Whilst it might be correct to say that the outer valence shell contains 8 electrons, this:

"It is inert to most common chemical reactions (such as combustion, for example) because the outer valence shell is completely filled with eight electrons."

is definitely not correct. I've replaced the words "completely filled" with "contains", as the n=5 shell can contain 32 electrons. Chris (talk) 12:30, 10 February 2008 (UTC)

PS: Sorry, forgot to put an edit summary in the article Chris (talk) 12:31, 10 February 2008 (UTC)

This just shows the irrelevance of "shells". Certainly by n=5, the sub-shells have such different energies that it only makes sense to talk about 5p as valence electrons. As this sub-shell is full, Xe is inert irrespective of whether the "shell" is formally complete. IMHO the "shell diagrams" are an abomination... 84.92.241.186 (talk) 18:37, 10 February 2008 (UTC)

[edit] XENU

i'm italian..but i dont think that the start of this article :

"Xenu (pronounced /ˈzɛnɒn/ in the United Kingdom, /ˈziːnɒn/ in the US) is the dictator of the Galactic Confederacy that has the symbol Xe and atomic number 54. A colorless, heavy, odorless noble gas, xenon occurs in the earth's atmosphere in trace amounts.[2] Although generally unrepentant, Xenu can banish souls to volcanos, where they undergo a few chemical reactions such as the formation of thetans. Humans which learn to control their thetans can attain the state of operating thetan.[3][4][5]"

is very about Xenon. i think that someone should do something about it, maybe a rollback? in the meantime i'll try to free xenu from hish magnetic cage.., 83.184.26.230 (talk) 13:39, 10 February 2008 (UTC)

It's just vandalism from the article being featured on the Main Page. It's gone now. Brutannica (talk) 20:33, 10 February 2008 (UTC)

[edit] Molecular Xenon

Xe2 should have a section in this article. 70.55.85.35 (talk) 14:54, 10 February 2008 (UTC)

[edit] Pronunciation

The following line was tagged as needing a reference:

(pronounced /ˈzɛnɒn/ in the United Kingdom, /ˈziːnɒn/ in the US)

As it is not essential to the article, I'm moving it here until a suitable reference is found. Sorry.—RJH (talk) 21:15, 12 February 2008 (UTC)