Talk:Iodine
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I 2nd that someone should add staining to uses box.
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Article changed over to new Wikipedia:WikiProject Elements format by maveric149. Elementbox converted 15:52, 5 July 2005 by Femto (previous revision was that of 05:42, 4 July 2005).
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[edit] Information Sources
Some of the text in this entry was rewritten from Los Alamos National Laboratory - Iodine. Additional text was taken directly from USGS Periodic Table - Iodine, 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
It is a well known fact that iodine sublimes, but is it actually true? Sublimation is the transformation of a solid to gas without melting. Since Iodine has a melting point well below its boiling point it seems very strange that it would undergo sublimation. Apparently people seem to think that iodine sublimes because when they look at the solid they can see vapor rising up from it, which is only normal, since every solid, or liquid for that matter, is always in equilibrium with its own vapor. Since iodine has a visible vapor people mistake it for the process of sublimation.
Yes, it's true. All solids sublime to some extent, but some so slowly that it can be ignored. Since iodine vapour is so colourful, it gets noticed. JohnSankey 14:43, 27 September 2005 (UTC)
Why was the added history information labeled as vandalism?
- Because the added information had nothing to do with Iodine and had a sentence fragment at the end.
- Darrien 01:29, 2004 May 13 (UTC)
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- Good point. =P. it's all better now though. is it satisfactory?
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- Yes.
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- P.S. I suggest that you sign your posts with "~~~~".
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- Darrien 12:17, 2004 May 13 (UTC)
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The page appears all weird with Mozilla Firefox, the margin text box runs together with the main page.
The history section mentions treating seaweed ash with hydrochloric acid and then in the next sentence replaces it with sulfuric acid. Apparently one is wrong, but I don't know which one is correct. Anyone able to fix this up? --66.188.84.209 07:56, 20 Jan 2005 (UTC)
- The iodide in the seaweed ash needs to be oxidized in the presence of acid, so sulfuric or nitric acids would work, but not hydrochloric. Hydrochloric acid can be used with a suitable oxidizing agent such as hydrogen peroxide.--24.16.148.75 17:25, 25 June 2006 (UTC)
I took out the mention of iodine being 'insoluble' - it's soluble in lots of liquids, as already noted in the next section. JohnSankey 14:43, 27 September 2005 (UTC)
[edit] Pranks?
Oh come on. I would like to see one single source for Nitrogen Triiodide being commonly used in college pranks. I will remove that sentence in a week or so if no one can provide one. I have known of its being used in a Harvard dormitory in 1953. Carrionluggage 07:06, 27 January 2006 (UTC) It was done when I went to college, in fact the Chemistry professors acknowleged it also happened when they went to college. It usually does not make the papers.
My A.P. chemistry teacher mentioned in passing that Nitrogen Triiodide had been used for pranks during his time as a student at the University of Washington. His comments encompassed the placement of the compound in question on door knobs and toliets. Kyanite 23:14, 11 September 2006 (UTC)
[edit] 137Cs
I doubt that a person could safely take enough KI to flush 137Cs after a nuclear fission "event" (fallout). I would tend to recommend KCl, which is even used as a table salt substitute (mixed with NaCl). I am working this with an expert chemistry professor and when I hear back I may change the page on the aesium item. Carrionluggage 07:06, 27 January 2006 (UTC)
Indeed, you couldn't do it safely with KI. You might run Cs out a little faster by taking a potassium supplement, but it would have to be at medical doses (4 grams a day of K or so as slow release tablets). The biological half-life of Cs is short, and its radiologic life is irrelevent. I don't think there's much point in worrying about Cs-137 as it doesn't build up in the body (running out like potassium) no matter what you do. For a dirty bomb using fission products, the next worst isotope to worry about, after I-131, is Sr-90, which collects in bones and causes a severe dose that way. Take your TUMS to help prevent that ;). Sbharris 05:37, 19 May 2006 (UTC)
[edit] Vandals
Please stop your purile behavior on this page PrometheusX303 00:55, 21 March 2006 (UTC)
[edit] Sublime vs. sublimate
Sublimate is the proper verbal form of the noun sublimation (see sublimate vs sublime à la American Heritage). It makes more sense, and follows more logically, from sublimation. It also has no other definitions, whereas sublime is more commonly associated with things unrelated to Chemistry.—Kbolino 05:14, 21 March 2006 (UTC)
- Sublimation is the derivative, not the basic term; talking about sublimate following "more naturally" from sublimation is therefore erroneous. Anyway, in the Merriam-Webster dictionary, sublime is the basic form ([1]); sublimate merely has a redirection to sublime ([2]). Sublimate seems to be a back-formation from sublimation in much the same way as orientate was formed from orientation. Thefamouseccles 06:41, 29 July 2007 (UTC)
[edit] Question about volumetric iodine solution
Could anyone explain to me why a 0.1M iodine solution sold for volumetric analysis is sometimes quoted as 0.1M (0.1N) and sometimes as 0.1M (0.05N)? What is actually in this solution? Thanks! OAP boba 08:20, 27 April 2006 (UTC)
- Here's an MSDS for 0.1 N volumetric iodine solution, and it's not much help. [3]. Yeah, they put 12.7 g iodine in a liter, which means it's 0.1 N if (and only if) your "formula" to make up the solution is is I and nothing but I. (Normality is formula weight per liter solution). But everybody knows that the stuff added as "I" is the solid I2, and when you add it to KI in water (as here, because this solution also contains more K+ and I- than I) it turns into I3-. So "normal" is meaningless in this situation, and so is "molar". You have 0.1 mole titratable elemental iodine per liter. But that's not 0.1 molar, since most of this stuff is in the form of I3-. These solutions are 4% KI, which means they are 0.24 molar in K+ and 0.24 molar in I-, or would be if the I2 wasn't added. As it is, the I2 is added and 0.1 mole/L reacts with I-, so the solution is probably 0.24 molar K+, 0.1 molar I3-, and (the remaining unreacted) 0.14 molar I- or so. Since there is no valid formula weight being used, all motions of "normal" are out the window, IMHO. SBHarris 02:53, 27 October 2006 (UTC)
[edit] Staining
Iodine can be used as a stain when viewing cells under a microscope. Someone should add this to the "Uses" section.
[edit] Isotopes
Mistakes about Iodine 131:
The I-131 is a beta and gamma emissor, and its energy are 192 keV (beta) and 364 Kev (gamma). The info is wrong, as you can see at http://www.iem-inc.com/toolabsr.html or http://www.rxlist.com/cgi/generic4/nai131.htm
--Saragc 08:46, 26 July 2006 (UTC)
ion Isotopes says: "129I (half-life 15.7 million years) is a product of 129Xe spallation in the atmosphere" and later in the same section says: "129Xe in meteorites have been shown to result from decay of 129I"
I am confused. In the end, 129I generate 129Xe or 129Xe generate 129I ?193.52.24.125 13:08, 1 May 2006 (UTC)
- I don't know the answer for sure on the spallation, but can tell you that the I-129 to Xe-129 transformation by beta decay is correct and has been used for dating (don't ask me how, since the 15 MY life is too short, I would think, for solar system objects-- all primordial I-129 is gone so all the Xe-129 you find in I is from I-129, but so what?)
- As for I-129 produced in the atmosphere from Xe spallation, I've read that, but nobody says what isotope of Xe it's from. My guess is that your statement that it's Xe-129 is in error (somebody's assumption). I'd demand a source for it, or delete or change to generic Xe. Spallation knocks particles off. If a proton comes in (and essentially it's always a proton for cosmic rays) and a proton goes out, you get no net change. If you have proton in neutron out (p,n) then you get an isotope which increases by atomic number, and here we want to go the other way from Xe(54) to I(53) which means we need to lose a net proton. The only good way to do that is with a proton in, is a 2 proton out scheme (p,2p) and in that case your atomic number goes down by one, so if you want I-129 you need to start with Xe-130 and basically knock 1 net proton off it. Fortunately, 4% of naturally occuring Xe in the atmosphere is Xe-130. My guess is that's where the I-129 is from.Sbharris 20:32, 25 May 2006 (UTC)
[edit] Tincture of Iodine
I believe sodium iodide is a component as well, in fact with this the alcohol is not necessary.
- Technically, alcohol is needed for "tincture" (see tincture of iodine, but there is a Lugol's iodine as well, which is the K+I3- solution you describe. Isn't WP amazing? I'll add the links.Sbharris 23:23, 7 June 2006 (UTC)
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- Yes, but the alcohol is added just to make it 'sting'. Without that, youngsters might actually be more co-operative...
Tincture of iodine is a solution of 2-3% iodine in ethanol. Lugol's iodine is a solution of iodine in potassium iodide. Kyanite 01:01, 18 September 2006 (UTC)
[edit] Least Reactive
I had thought Astatine is the least reactive of the halogens. It does say Astatine is more electropositive, but I thought Astatine was expected to be less reactive even though not enough of it can be collected to do much experimentation with.
[edit] "Price" section
Why is this section even here? The value of things always change; the reader does not need numbers to understand that concept, or a whole section comparing the price of iodine year after year to get the point. A simple sentence about the increased value of iodine should suffice. Section also illustrates one point of view by stating the US dollar price. Other weaknesses such as sentence structure, grammar, and 1st person narrative tone pointed out that the section needed deletion until much further improvment and editing!--Stoa 05:04, 5 November 2007 (UTC)
[edit] Neutron amount?
the first time i looked up iodine on wikipedia was 09/02/2008. for my research i had to write down the mass number and atomic number of iodine. my first intention was the read the info off the periodic picture on the right, but the number of neutrons was 76 (Image:I-TableImage.png) where the number of neutrons in the article was 74. although this is a small problem it is a problem none the less, and i would like to see the some correction. —Preceding unsigned comment added by 218.215.95.238 (talk) 23:15, 8 February 2008 (UTC)
[edit] Properies (color)
...under standard conditions is a dark-purple/dark-brown solid.. In the image it more looked grey. -Yyy (talk) 10:27, 26 May 2008 (UTC)
