Talk:Nitrogen triiodide

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Was the first paragraph of this plagerized? Compare to the first paragraph of this: —The preceding unsigned comment was added by Ajladine (talkcontribs) 00:56, August 22, 2007 (UTC).

You have the situation reversed: Lots of websites take their text from WEchem.--Smokefoot 02:41, 22 August 2007 (UTC)[reply]

why does this explosion occur? Why is the compound so delicate? how is it used? how is it kept safely? Kingturtle 04:18 8 Jun 2003 (UTC)

This site has a good overview on the compound. I believe that it can be kept stable in an aqueous solution or in pure liquid form. It does not have any uses as far as I know besides to demonstrate it explosiveness. -Eszett 16:17 10 Jun 2003 (GMT -5)

The reason for the explosion can be worked out by the same means any chemist would use - determining the energy of the products (N2, NH4I, I2, NH3) relative to the reactants (NI3, or NI3.NH3x). The aqueous solution is not stable; only the ammonate (NI3.NH3x) is stable. If an aqueous solution becomes depleted of ammonia (by formation of a higher ammonate or escape of gaseous nh3 from the soultion), it becomes unstable.

I removed the bit about spreading it on the floor and having people step on it. It's neat, and it's not very dangerous, but I don't think it belongs in an encyclopedia. And it stains feet, and any excess iodine can burn a bit. It just doesn't belong there. Nick 22:47, 17 December 2005 (UTC)[reply]

World of Chemistry[edit]

I saw Don Showalter demonstrate the reactive tendencies of nitrogen triiodide with a feather on World of Chemistry. I recall it was mentioned somewhere on the wiki.

Transwiki section?[edit]

Does the home-preparation section belong on Wikipedia? I'd say it'd be more at home on Wikibooks. GeeJo (t) (c)  09:59, 6 February 2006 (UTC)[reply]

Nitrogen triiodide really the same thing as ammonium triiodide?[edit]

Previously the article listed the two as synonymous, however aren't they NI3 and NH4I3 respectively? If they are the same, an explanation is in order in the article somewhere. For now I've removed "ammonium triiodide" from the opening paragraph. If someone puts it back can they please an an explanation as to why they are the same? 23:08, 16 May 2006 (UTC)[reply]

Error on the reason for instability of NI3[edit]

A small error on the stability of the compound. It is not due to the stability of the products. That has nothing to do with the activation energy of NI3. The instability of NI3 is mainly due to the relative sizes of the Nitrogen and the Iodine. Since the Iodine atoms are huge in size compared to the Nitrogen atom, they are packed close together. This causes high repulsive forces between the 3 Iodine atoms, causing instability of the molecule. —Preceding unsigned comment added by (talk) 22:24, 21 October 2007 (UTC)[reply]

That is an insightful proposal, or at least helpful to me because you are separating the kinetics from the thermodynamics. But it is your theory might not be admissable (Wikipedia:No original research). As indicated by Marcus theory (the article is in rough shape), the activation energy is coupled to the thermodynamic driving force. --Smokefoot 22:35, 21 October 2007 (UTC)[reply]
I think there might be some merit to the idea that the instability of the compound is due to steric repulsion. However, we would need a reference we can cite, and I haven't been able to find any. Has anyone studied the mechanism of decomposition in detail? There are other possible explanations, for example, that the compound is unstable because of the weak N-I bond, due to the poor overlap between atoms that are so different in size. --Itub 12:33, 22 October 2007 (UTC)[reply]

While it doesn't really answer this question, this article has some interesting information regarding the thermodynamics of the reaction. Tudela, D. Journal of Chemical Education 2002, 79, 558. Full text --Itub 11:06, 6 November 2007 (UTC)[reply]

Explosive preparation[edit]

I deleted the section describing the step-by-step preparation process of the explosive NI3. This kind of information does not belong here. JEFCG 30 June 2006.

Why doesn't it? Where exactly does one end the stifling of free exchange of information? --Mfree 19:08, 21 July 2006 (UTC)[reply]
Agreed, and restored. I suspect an ulterior motive here. ~ Eidako 16:58, 30 August 2006 (UTC)[reply]
I have removed it again .. Wikipedia is not a manual, per WP:NOT --Dirk Beetstra T C 17:06, 30 August 2006 (UTC)[reply]
There's far worse violations of this to be found on Wikipedia (drowning, shallow water blackout, sailing, virtually any video game article), but okay. Would either of these be acceptable (in order of preference)?
1. Rewrite the section to provide a general outline of how it may be prepared, but in a neutral, non-instructive format, in the vein of the "NI3·NH3 explosions leave orange-to-purple iodine stains that are difficult to wash. However, they can be easily removed by sodium thiosulfate solution" comment currently in the article.
2. Provide a link to an offsite set of instructions.
~ Eidako 16:53, 1 September 2006 (UTC)[reply]
That there are other articles violating WP:NOT is not the question here, and maybe someone should look at the things on these pages as well. But now for consensus.
WP:NOT gives a commonplace for instructions (err .. wasn't it wikibooks?), so that is anyway a good solution (and one can provide a link to there from here, there is a template for that). I think there is not much wrong with a non-instructive outline (I guess it fits into one sentence, or one must choose to tell more about the mechanism of its formation. So both are good suggestions, I think that is the way to go. --Dirk Beetstra T C 17:04, 1 September 2006 (UTC)If iI rmeeber corrcetly.Iodine crfystals from which Trinitrogen iodide made .Is also used to make Meth! SWORDINHAND (talk) 20:47, 5 July 2009 (UTC)[reply]

OK. After reading up on what was said above, it's true, it shouldn't be spelt out (UK spelling). However, links should be given to show people how it is made because it's a fun thing for kids to try.


"Gunpowder like snap". WTF? Gunpowder does not detonate and thus does not give a snap like this substance does. Where does that line come from? I find it somewhat inaccurate. — Preceding unsigned comment added by (talk) 06:46, 7 June 2012 (UTC)[reply]

Agreed. Came here to say that. Will edit. — Preceding unsigned comment added by (talk) 18:23, 28 January 2013 (UTC)[reply]

-290 kJ/mol behind decomposition equation[edit]

Which thermodynamical dimension is this? Is it the reaction's enthalpy ΔH or the reaction's free enthalpy ΔG? If it is ΔRH, the value is a bit strange because it is less than the ΔRH of the equivalent reaction with NCl3 (ca. -460 kJ/mol), implying that the thermal decomposition of NCl3 is more violent (even if it occurs at higher temperature due to higher kinetic stability) than that of NI3. As far as described in the articles, the opposite should be the case... -- (talk) 20:51, 6 September 2013 (UTC)[reply]

In accordance with the German wiki "Stickstoffhalogenide", 290 kJ/mol is the enthalpy of formation (ΔfH) for NI3, that means -290 kJ/mol is the decomposition reaction's enthalpy for one molecule of NI3. That is also what I expected most. So the reaction enthalpy for the reaction given in the text must be -580 kJ/mol, since there are two molecules of NI3 decomposing. I only don't know where the value is taken from in the German article, because that article also cites no sources for the ΔfH of NI3 being +290 kJ/mol. So that should better be checked before the value in this article is corrected... -- (talk) 15:33, 13 September 2013 (UTC)[reply]

Lewis Structures[edit]

Would it be possible to start adding Lewis structures to help beginning chemistry students understand the bonds between the atoms as in double bonds and the like Samuel P. aka Unknown9876789 (talk) 15:15, 4 March 2014 (UTC)[reply]

Assessment comment[edit]

The comment(s) below were originally left at Talk:Nitrogen triiodide/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

A small error on the stability of the compound. It is not due to the stability of the products. That has nothing to do with the activation energy of NI3. The instability of NI3 is mainly due to the relative sizes of the Nitrogen and the Iodine. Since the Iodine atoms are huge in size compared to the Nitrogen atom, they are packed close together. This causes high repulsive forces between the 3 Iodine atoms, causing instability of the molecule.

Last edited at 22:22, 21 October 2007 (UTC). Substituted at 01:20, 30 April 2016 (UTC)

Is this the heaviest gas?[edit]

The infobox says sublimation at −20 °C: compare NI
(395 g/mol) to WF
(298), although W(CF
isn't ruled out. What's the source for −20 °C? Alfa-ketosav (talk) 11:48, 5 September 2018 (UTC)[reply]

"Heaviest gas" has no meaning that I can think of. Sublimation is not abrupt and there is no characteristic Tsub. My 2 cents.--Smokefoot (talk) 11:55, 13 December 2018 (UTC)[reply]


Youtube is full of videos showing an explosion and purple cloud. This article should say whether that purple cloud is toxic.

The first paragraph of this article says "...releasing a purple cloud of iodine vapor", but later the article says

"The dry material is a contact explosive, decomposing approximately as follows:

8 NI3 · NH3 → 5 N2 + 6 NH4I + 9 I2"

So which is it? "Iodine vapor"? Or is the purple cloud a combination of Ammonia, Ammonium iodide, and Elemental Iodine (I2)? And is the purple cloud an actual vapor or is it a cloud of solid (liquid?) Iodine particles? Iodine boils at 113.7 °C and Ammonium iodide boils at 551 °C so (based upon my extensive education (which consists of getting a C- in high-school chemistry) it seems that only the Ammonia would be a vapor, while the purple stuff would be an aerosol.

Could someone who understands chemistry please write up a paragraph with citations explaining what is in that purple cloud and whether it is toxic? 2600:1700:D0A0:21B0:5A9:3B45:A28C:DE50 (talk) 18:40, 4 April 2022 (UTC)[reply]

Touch Powder as a name?[edit]

Nitrogen Triiodide is sometimes referred by the name "Touch Powder", I feel like it should at least be mentioned or added as a name. Tungster24 (talk) 23:02, 9 July 2022 (UTC)[reply]

Stability when wet[edit]

AsI know from producing histcompound when an A level student, it is stable enough to be easily transported when wet with water or alcohol. In fact even when damp with either liquid, if a flame is applied, it decomposes with the described iodine cloud, but not explosively. Once left to dry, a fly landing on it causes it to explode. (talk) 14:03, 23 April 2023 (UTC)[reply]