Nitrogen Triiodide

[Guest ginm]

I am planning to demonstrate the chemical principle of [extreme] decomposition at a science fair in one of my local middle schools. Obviously, the material that will be used is dry nitrogen triiodide.

 

So I need some suggestions:

 

1. How much iodine (grams) should I use when I prepare the wet nitrogen triiodide by mixing solid iodine with concentrated aqueous ammonia. I was thinking about 2-4 grams.

 

2. How long will it take for 2-4 grams of wet nitrogen triiodide to be dry enough to detonate upon touching?

[fafalone]

I hope you're not a student trying to do this... iodine vapors are very harmful and ammonia is strongly irrative

 

But for 1, just use stoichiometry

3/2 I₂ + NH₄ -> NI₃ + 2H₂

 

As a side experiment, you could collect the hydrogen gas in a test tube and you'll hear a pop when ignited with a match.

[wolfson]

Nitrogen triiodide, also called ammonium triiodide, is a very unstable explosive that's not really practical due to its tremendous instability and cost.

 

Nitrogen triiodide is formed when iodine atoms displace the hydrogen atoms in ammonia NH3 + I = NI3.

 

Add 2 g of iodine crystals to the beaker, crush them as much as possible with a stirring rod. Add 40 mL ammonium hydroxide to the beaker. After 2 hours the reaction should be complete. Pour the solution over a filter to collect the crystals, any excess can be rinsed out of the beaker with water. Put the crystals where you want them immediately because there only semblance of stability is when wet. Drying will take about 1 hour. You will need a graduated cylinder for measuring liquids.

 

Reference to http://www.roguesci.org/megalomania/explo/nitrogen_triiodide.html

 

I would not do this unless you are a chemist, like myself.

[Cap'n Refsmmat]

Isn't it a contact explosive?

And you said, "detonate upon touching." That's dangerous! You'll burn your hand.

[greg1917]

This would make a very good science fair experiment provided you are careful and are aware of the reaction conditions.

 

Ammonium triiodide, if made in small enough quantites, can make an impressive flash and in a safe manner.

 

I cant rememebr the exact recipe but the final stage of the reaction is cooling a liquid to a solid. as a liquid its perfectly stable - however when solid, NOW it becomes the explosive little rat were looking for.

 

Dont do this final stage in a beaker. My chemistry teacher did this, and the reaction was so quick it blew the bottom of the beaker straight out.

 

Instead, just pour a little onto some filter paper. That way there'll be no shards of glass flying around when it goes.

 

Also, bear in mind the activation energy curve for the decomposition is absolutely miniscule. Breathing will be enough to make it go, so ANY sudden movements and its gone. best to let it cool and not move it from that spot until you set it off. Basic rules apply, safety specs etc.

 

Other than that, its a good idea and will make a cool presentation.

[YT2095]

when dry, it`s about as stable as REALLY unstable thing during an earthquake having a bad day!

it also stains quite badly too, although it`s perfectly safe while in liquid form, just be carefull not to get any around the lid!

never store it more than 24 hours as it breaks down naturaly anyway, and if you MUST store it, never make more than you`ll need and keep it in a SOFT plastic container in liquid form and surround it with Pumice.

Stay safe!

[Invader_Gir]

How can I get NH4OH from household ammonia?

[budullewraagh]

actually, people dont call it [math]NH_4OH[/math] anymore; (even aqueous) it's [math]NH3[/math]

[Invader_Gir]

Ok, but on the back of the bottle of ammonia, it says ammonium hydroxide, NH4OH, is it not?

 

Anyways...the question still stands, How can i get NH3/NH4OH out of household ammonia.

[jdurg]

You could try and distill it out. Whenever I make nitrogen triiodide, I just use clear, nothing else added, ammonia that I buy from the grocery store. If you want to concentrate it, you could just get a small glass jar and put a very small bit of water in it, then connect it to another bigger jar that will house the ammonia. Then you just heat up the weak ammonia to just below the boiling point of water and you will drive a good deal of the ammonia out of the original solution, and it will then travel over to the smaller vial with the little bit of water in it and absorb into there. Then that solution of ammonia will be much more concentrated.

[budullewraagh]

Ok, but on the back of the bottle of ammonia, it says ammonium hydroxide, NH4OH, is it not?

it's a technicality. dont worry about it.

 

also, when distilling ammonia, be careful, lest it touches you and burns your arm off

[Invader_Gir]

burning flesh and dismembered limbs....sounds like fun!

 

But seriously, I think I might have to go to a bigger store, because i cannot find any ammonia that doesnt have anything else in it. Then again, going to a grocery store in a town with 600 people.....

[5614]

so is ammonia NH3 or NH4OH?

 

im not talking what its called, whats it chemical composition?

[YT2095]

Ammonia is NH3.

NH4OH is ammonium Hydroxide.

[5614]

ok, good good... just that:

 

"How can I get NH4OH from household ammonia?"

you cant get it from (ie. extraction) but you can make it (by making a hydroxide)

 

"Ok, but on the back of the bottle of ammonia, it says ammonium hydroxide, NH4OH, is it not"

then it wouldnt be a bottle of ammonia would it?!!!!!!

 

"it's a technicality. dont worry about it."

but surely its a different chemical... not only a technicality

 

anyway, that lot confused me a bit!

all ok now

[Gilded]

I wish we had science fairs here in Finland. They'd be so much fun.

[Invader_Gir]

"then it wouldnt be a bottle of ammonia would it?!!!!!!"

Its household ammonia. It says ammonia on the front, but in the ingredients it says solution of ammonium hydroxide and some other stuff. We made NI3 in chemistry the other day, and we used NH4OH, not household stuff. I was wondering HOW I would get the NH4OH out of the household stuff. I decided that in the end i am just gonna order some NH4OH off of the internet

[5614]

wouldnt it be easier to just buy some NH3 and add some iodine making NI3, shown in post #2?

 

or is NH4OH cheaper than NH3?

also, how would you get rid of the hydroxide part of NH4OH?

[YT2095]

you don`t need to get rid of it?

 

and How do you expect to contain NH4? it`s a gas at room temp!?

 

 

add some caustic soda to Ammonium Nitrate soln and distill it, that`s how I`ve made mine in the past (I buy it now if I need it).

[5614]

"you don`t need to get rid of it?"

 

if you wanted to do I2 + NH3 -> NI3 + H2 then you wouldnt want NH4OH, unless the OH just gets lost with the H when the I is added...?

 

"and How do you expect to contain NH4? it`s a gas at room temp!?"

well i was thinking not at room temp (rt), well, ok i wasnt thinking straight at all! but you could always (theoretically) keep a gas in a bottle! (with a lid on!).

[YT2095]

"you don`t need to get rid of it?"

 

if you wanted to do I2 + NH3 -> NI3 + H2 then you wouldnt want NH4OH' date=' unless the OH just gets lost with the H when the I is added...?

 

"and How do you expect to contain NH4? it`s a gas at room temp!?"

well i was thinking not at room temp (rt), well, ok i wasnt thinking straight at all! but you could always (theoretically) keep a gas in a bottle! (with a lid on!).[/quote']

for a start I`ve NEVER known Nitrogen Triiodide even made with pure ammonia (in fact I don`t think it`ll even work!).

 

the second part of you post is just plain stooopid!, try keeping it in a bottle "with the lid on" and I wouldn`t want to see the consequences!

at the least you`ll be up the hospital with respiratory problems

[Skye]

A solution NH4OH would have to contain some NH3, eg.

 

NH4OH <--> NH3 + H2O

[5614]

the second part of you post is just plain stooopid!, try keeping it in a bottle "with the lid on" and I wouldn`t want to see the consequences!

at the least you`ll be up the hospital with respiratory problems

soooooo? you still will would have kept it in a bottle!!!!! for a short amount of time, yeah it was meant to be stupid , but still..... something to think about! and not do any more than the thinking part!

 

skye: "h" meaning what?

[YT2095]

[indent']h[/indent]

YT passes Skye another beer, Nice post dude )

[Skye]

Sorry, I was playing around, and hit submit, rather than preview.

 

Thanks for the beer!