Talk:Sulfur hexafluoride

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lewis structure diagram?

I question the physiological effects of xenon, since it is an inert gas... displacement of oxygen could cause light headed sensation. Source?? Bert 03:48, 13 April 2006 (UTC)

I once read in a medical textbook that xenon can be used as a general anaesthetic, like nitrous oxide, but with fewer side-effects due to its lack of reactivity. It's not simply due to displacement of oxygen by Xe. See for example [1] , [2], [3].

--Ben 10:15, 13 April 2006 (UTC).

Thanks for the references. I've added the info on xenon's anaesthetic properties back into the article. Bert 13:03, 13 April 2006 (UTC)

As you go down the periodic table, the nobel gasses become less inert. Compounds exist. AlbertCahalan 03:31, 15 May 2006 (UTC)

Contents 1 Is this true? 2 High Voltage is not 1kV 3 Lewis Dot Structure 4 Contribution to global warming... 5 "Not a directory" 6 Youtube videos 7 Self-Healing? 8 Density 9 Constant-Pressure Specifc Heat of SF6

[edit] Is this true?

Just curious:

"According to my rough estimates the Moon could hold an atmosphere of SF6 (a stable, inert gas) at one bar of pressure for an indefinite period of time. That is if it's protected from solar wind. Light gasses like N2 or O2 would float off even without solar wind. If you wanted to terraform the moon you could put a atmosphere of SF6 to make the pressure and temp comfortable. Then continuously replenish the O2. So mechanism based on genetic engineering of microbes or maybe chemical methods could be used to keep the O2 from flying away. Either way solar wind would still be an issue." (from a board somewhere) Mithridates 02:42, 22 August 2006 (UTC)

So... what purpose would the SF₆ serve? Does it act as a greenhouse gas? —Keenan Pepper 05:45, 22 August 2006 (UTC)

I think its main purpose would be to create an atmosphere thick enough that other gases could be added without being knocked out right away, as well as to be thick enough that people would only need oxygen tanks when going outside instead of pressure suits as well. In theory anyway. I don't know anything about this gas. Here's the thread by the way so you can see where the discussion's come from. Mithridates 06:07, 22 August 2006 (UTC)

[edit] High Voltage is not 1kV

High Voltage does not start at 1kV this would be medium voltage. Albeit that warning signs are always going to say HIGH VOLTAGE even if the voltage is 480/277 this is for deterrent purposes. However sometimes in a 480/277 volt three phase distribution system within a building the 480 is referred to as high voltage while the 208/120 voltage is referred to as low voltage, in reality they both fall under low voltage. To further complex things article 490 of the 2005 NEC (for the purpose of the article) calls anything over 600V high voltage. Medium Voltage is typically 5kV-50kv (4160 and 4800 volt systems are typicall classified as 5kV systems)keep in mind there is a difference between "system voltage" and "utilization voltage". Anyway "High Voltage" doesn’t start until approx 50kV; my suggestion is you remove the reference of 1kV and state SF6 is typically used in medium and high voltage electrical applications.

[edit] Lewis Dot Structure

How can sulfur accept 6 fluorides? It doesn't have d-orbitals to accept extra electrons, or is there something I'm forgetting?

Indeed, d-orbitals are considered too high in energy to contribute to bonding. In the terminology of Molecular Orbital Theory, bonding is such species are decribed by 3-center, 4-electron bonding, which in effect places substantial electron density on the highly electronegative F atoms. Such molecules are caled hypervalent. PF₆^- and SiF₆^2- are isoelectronic with SF₆. SF₄, SO₂, SO₃, SF₂O₂, and, indeed, H₂SO₄ are described with this approach. Ignoring bonding theories, most main group elements heavier than Ne, can bind at least six F atoms around themselves.--Smokefoot 04:13, 25 September 2006 (UTC)

[edit] Contribution to global warming...

Is that information regarding SF6's GWP accurate? If SF6's GWP is indeed 22,500 over 100 years, and its mixing ratio is indeed 0.005 ppm, it will have a net effect only 1/3 that of the net effect of carbon dioxide (GWP 1, mixing ratio 365 ppm). Hardly "low".

It's an error. I checked, after getting to the same conclusion as you. According to http://www.epa.gov/highgwp/scientific.html#sf6 : Measurements of SF6 show that its global average concentration has increased by about 7% per year during the 1980s and 1990s, from less 1 ppt in 1980 to almost 4 ppt in the late 1990’s (IPCC, 2001). The value 0.005 ppm is off by a factor of 1000 (0.005 ppm would be 5 ppb, which is 5000 ppt). I can edit that later today, if noone objects. Oku 23:23, 11 January 2007 (UTC)

Please do. I came to this talk page with the exact same question in mind 71.146.130.162 01:59, 12 January 2007 (UTC)

Done Oku 06:02, 12 January 2007 (UTC)

[edit] "Not a directory"

The complaint that wikipedia is "not a directory" is an awfully weird excuse to remove a link to what I think is a quite informative demonstration video showing the density of SF6. I'm going to list at RfC 'cause I'd really like to keep it. --Deglr6328 09:40, 10 January 2007 (UTC)

WP is not a mere collection of links. There is no reason to just add more and more external links to a page. Youtube is already a site that is under dispute, and though the video shows a nice demonstration, it does not tell more about the compound. --Dirk Beetstra ^{T C} 09:55, 10 January 2007 (UTC)

I re-reviewed the video. The only reference directly says 'hexafluorid', which does not say that this is actually sulfur hexafluorid. There is no explanation, there is no extra data. I'm sorry, but this is just another external link, you can also post this on Xenon (where there is sure that hexafluorid is not Xenon, of course). It might make a nice reference on explanation of gases with high molecular weight. --Dirk Beetstra ^{T C} 10:01, 10 January 2007 (UTC)

Right, because there's a good chance it could actually be hot uranium hexafluoride. Give me a break. --Deglr6328 01:17, 14 January 2007 (UTC)

[edit] Youtube videos

I have removed this link:

• Video demonstrating Effects on human voice

It is not to a true youtube page, but to a somewhat trashy site. About these links, I don't mind if they appear as references, as plain external links they are not really useful, the wikipedia is not a mere collection of external links, see sites like wp:not, wp:el. If someone would like to write a properly written part in the article, using this as a reference (I'd prefer peer reviewed references as well ..), please go ahead. Thanks. --Dirk Beetstra ^{T C} 11:02, 14 January 2007 (UTC)

But what about the original link? http://youtube.com/watch?v=a9ifZlu6YKk 82.195.149.147 21:38, 20 January 2007 (UTC)

I think that is covered in my previous answer. --Dirk Beetstra ^{T C} 01:19, 21 January 2007 (UTC)

[edit] Self-Healing?

I removed the line about SF6 being self-healing. It doesn't seem to make sense when the article continues to discuss the decomposition products.

Self-Healing seems like a strange term for a gas, which would be unfamiliar to many readers. Perhaps if someone made an article self_healing(gas) or something... 129.78.208.4 03:29, 22 January 2007 (UTC)

[edit] Density

One paragraph says it's 5 times air's density, another says 6. Which is it? Miken32 06:10, 23 February 2007 (UTC)

However its density (5 times as heavy as air) necessitates proper mixing.

I removed the odd sentence here, as seems unclear in its meaning. If the figure of 6.13 g/cm³ is anything to go by, and the density of air being anywhere between 1.1 and 1.3 g/cm³, I make it 5.11 times denser. That's still pretty dense for a gas, is there any chance that this as the densest (ambient) gas in the world? — Jack · talk · 11:08, Saturday, 31 March 2007

I changed the above density statement and added values for SF6 density for all three phases. While there may be a number of gases that are heavier than SF6. the densest known gas (at STP) is radon (9.73 g/L) - almost 1.6 times the density of SF6 (6.16 g/L). Bert 17:49, 31 March 2007 (UTC)

[edit] Constant-Pressure Specifc Heat of SF6

The specific heat of SF6 will change with respect of temperature. I'll appreciate if anyone knows the coefficients that build the 'ideal' gas specific heat (with constan pressure) equation, or any good link on this topic. It goes like C_p0=C₀+C₁θ+C₂θ²+C₂θ²

Where the θ=T(Kelvin)/1000 —The preceding unsigned comment was added by Milovac (talk • contribs) 19:22, 5 April 2007 (UTC).