Nitrogen Triiodide (2016)
63 comments
·May 29, 2025bognition
rdtsc
This stuff would go off immediately if you touched it.
I used to make it with my friends with household ammonia and medical iodine. We mixed them and then filtered through paper. Then this brown powder would explode after it dried if we touched it just lightly.
keepamovin
It's crazy that something so unstable can even exist at RTP. Like it's interesting how it threads the line between so-unstable-you-can't-make-me, and stable-enough-to-make-but-decompose-under-a-stern-glance. Universe has a sense of fun, NI3 is tuned specifically for existence as a prank substance.
rdtsc
> Universe has a sense of fun, NI3 is tuned specifically for existence as a prank substance.
It does feel that way! Another plus for the substance is just releases iodine, not something poisonous like lead for instance.
IAmGraydon
You would know if it was NI3 - it creates a deep purple cloud of sublimated iodine when it detonates and it stains everything around.
bognition
This was nearly 30 years ago, so honestly i don't remember much beyond the fun of hearing things explode under the wheels of my rollerblades
gsf_emergency
Do you remember purple smoke?
bognition
This was nearly 30 years ago, so honestly i don't remember much beyond the fun of hearing things explode under the wheels of my rollerblades
pinoy420
[dead]
toddm
!
colanderman
I'm not a chemist, but the article talks about it being prepared in a solution of ammonium hydroxide which can be poured on a floor and left to dry. Surely this is what the GP is comparing their memory to, and not a bucket of pure nitrogen trioxide.
JKCalhoun
A fun thing to make. I made this in the high school chemistry room after school. Filter paper with some iodine crystals, pour some ammonia over and wait for it to dry (as I recall). I am not sure where I learned about it. Often my dad, who was a chemist then, would tell me little tricks like this. (He also turn me on to slathering a small amount of potassium permanganate with glycerin.)
Anyway, I was walking with it after I made it (when it was still damp and in the filter paper) and I accidentally dropped the filter paper in the school hallway. I picked up what I could (I suppose I should have gone back and mopped it up).
It was fun, the small explosions, like tap shoes clacking, when it was dry and walked upon. (Too bad it left brown stains on the linoleum.)
I was fortunate to have not had a large quantity dry. It can be pretty dangerous in large amounts I am told.
BoxOfRain
My A-level chemistry teacher liked to paint it onto door frames and in the hallways. Apparently one day he'd left some out in his lab in preparation for this prank, then the school had a surprise inspection. He had to teach his class in front of the inspectors while being constantly interrupted by small purple explosions.
He also liked to let off expired fire extinguishers at his sixth formers out of his window, and he once attempted to use them to propel a pupil sitting on a wheely office chair. Very memorable teacher!
vunderba
I've always heard that the incredibly sensitive volatility of this compound precludes the ability to even amass it in large quantities, because it will essentially fulminate under its own weight.
cperciva
I accidentally dropped the filter paper in the school hallway
It's wonderful when "accidents" like this happen.
hilbert42
It's a great shame John Walker is no longer with us, he was a bright fellow (even though I thought his company's products were too expensive). I loved his Hacker's Diet book, a true techie's approach to dieting. Certainly worth a read if one's interested in such things.
No doubt those of us who've gravitated to this link like watching things that go bang so make sure you read Walker's link at the bottom of the Nitrogen Triiodide page to his article on FOOF—aka Dioxygen Difluoride (O2F2). Also, make sure you read the link in that page to Derek Lowe's blog in Science's site Things I Won't Work With.
Every chemist should read Lowe's blogs, they're not only informative but often entertaining. I've copied the FOOF link here for convenience (this truly is chemistry at the bleeding edge):
https://www.science.org/content/blog-post/things-i-won-t-wor...
jpmattia
MIT has a long tradition of hacks, and among the first documented hacks in the 1870s for marching practice:
> in which students sprinkled iodide of nitrogen over the grounds of a military drill, causing explosions under classmates' boots.
https://www.slate.com/articles/life/culturebox/2012/02/mit_p...
keepamovin
Also notable this article is by John Walker, co-founder of Autodesk, who passed last year.
zahlman
Also the author of The Hacker's Diet. fourmilab.ch was a very interesting website.
neepi
This was a favourite for me at school. Had a great chemistry teacher. Always had something that blew up available.
This was motivational until I did A level chemistry a few years later. He vetoed my attempts to make RDX out of hexamine tablets and normal nitric acid. He got suspicious when I was trying to dehydrate nitric acid with sulphuric acid.
Good job I gave up on chem or I’d probably be dead or in prison.
Perenti
We used to steal Iodine crystals from the chem lab at High School, and set "traps" for the unwary. I have no idea how many clothes we ruined by putting NI3 on seats.
We also wired cans in || and wired up the boys' urinal so that they could "complete the circuit".
Ah, the Good Old Days before Workplace Health and Safety, or MDS.
zafka
This does bring back fun memories! My favorite application was to make the game of ping pong a little more random. Small amounts scattered across the table would result in puffs of purple smoke and the ball changing direction.
sb8244
I made this for my high school chemistry project. We made it in the morning so it would be ready for our afternoon class.
It was drying in the chemistry back office and there must have been a draft. It exploded during a silent study hall.
Somehow they let us remake it for class that afternoon. We tried to put it on the floor as a joke, but our teacher was wearing sandals that day (no lab). She wasn't happy about it.
I originally got the idea (and prank idea) the previous year from a retiring chemistry teacher.
keepamovin
lol - great story. So many good stories here about this stuff.
I agree with others who say it's dangerous, but only if you use sufficient quantities, or contained (don't contain!). A few crystals sprinkled in different places will just produce the pops and not hurt anything - I think! :)
From memory: size of a full stop or white sesame seed will already produce a very (but not painfully) loud bang; whereas a speck so tiny on the ground you can't readily see it from standing height is sufficient for a "walking over" prank, surprisingly loud for how tiny it is.
The ultrafast snappy pop and purple smoke is satisfying, but it does stain.
I like the comment about ping pong - hilarious use case.
chickensong
The Anarchist Cookbook had a recipe for this IIRC, called ANTI (Ammonia Nitrate TriIodide). My chemistry teacher was not pleased at the pits left in the classroom countertops.
gerdesj
Yes, its an old one. Inject it into a keyhole.
Kids - do note that the Anarchist's Cookbook is absolutely verboten in the UK at least. My old man was an ATO so I didn't need a copy.
The original AC will be several elements in every wordlist that every intelligence service ever has. It is probably quite close to EICAR in that world.
Terr_
> It is probably quite close to EICAR in that world.
I recall reading some story where the author was able to do a denial of service attack on a system by putting EICAR in it, causing a kind of autoimmune dysfunction.
Full_Clark
There's a good DEFCON 29 presentation on this topic. https://youtu.be/cIcbAMO6sxo
If you skip forward to 16m 33s you'll be treated to a lively streak of invective from the passenger of a car whose driver has just confirmed that feeding EICAR to a parking system prevents it from letting any vehicle past the barrier.
mrichman
I made this in high school, shortly after my AP Chemistry exam in 1992. I left it out to dry under the fume hood, and my teacher, not knowing what it was, moved it and BOOM! Fun times.
xiande04
Reminds me of my AP chem class 16 years later. We were always mixing stuff up in the lab. Good times.
chasil
This reminds me of triacetone triperoxide (tatp).
https://www.theregister.com/Print/2006/08/17/flying_toilet_t...
Oh wow! Growing up my chemical engineer uncle would come out on the Fourth of July and dump a bucket of stuff on the road in front of his house. A while later when it was dried he'd have us roller blade and skate board down the road to setup all the little explosions. It was a total blast. He refused to tell anyone what the compound was, but assured us it could be easily made. It has to be this stuff.