Thermite

[boris_73]

i have found a chemical which skylighter will ship to england and that chemical is the one which i want Bismuth Trioxide it cost about $21 for 1 pound so about £11 but its the only place that i have found which will sell it

[Gilded]

Bismuth trioxide seems to be quite unpopular in pyro, except for the dragon egg thing. :/

[ffsjoe]

Does anyone know the ratio for the iron oxide, aluminium and sulphur thermite?

I remember reading it somewhere I thought it was here but I've searched all over and can't find it.

[budullewraagh]

eh, that would make a flash powder more than a thermite. remove the sulfur and you have a thermite mixture.

 

by the way, all, who here has tried any exotic thermites?

[ffsjoe]

The purpose of the sulphur is to hold the mixture together so the rust doesn't separate from the aluminium. You heat gently it so the sulphur melts and holds its all together.

 

Thats what i remember reading, but i can't find it, hmm maybe i dreamt it up

[budullewraagh]

yeah but the sulfur will oxidize rapidly and it will act as more of a flash powder

[Lance]

why not just use plaster of paris?

[Silencer]

I found some chromium oxide powder in my basement... i think it is used by hardcore knife sharpeners.

 

Would this make a good thermite? What is it's formula likely to be? Also, wouldn't getting pure chromium be pretty sweet?

[budullewraagh]

it would make a thermite, that is for sure. i believe it is Cr2O3

chromium has several oxides: CrO2, CrO3, Cr2O3 and, Cr3O4, namely

 

best reactions for isolation of chromium would be

Cr2O3 + 2Al --> 2Cr + Al2O3

2Cr2O3 + 3Si --> 4Cr + 3SiO2

 

speaking of chromium...

http://www.webelements.com/webelements/elements/media/moov/volcano.mov

the above video is bloody amazing. change the tag to .mpg if you dont have quicktime

[budullewraagh]

i should add that chromium and its salts are carcinogens

[YT2095]

The purpose of the sulphur is to hold the mixture together so the rust doesn't separate from the aluminium. You heat gently it so the sulphur melts and holds its all together.

 

Thats what i remember reading' date=' but i can't find it, hmm maybe i dreamt it up[/quote']

the purpose of Sulpher in many Pyro compounds is to only lower the Activation energy (Heat).

[Silencer]

i should add that chromium and its salts are carcinogens

 

oh great! Thanks for the info though.

[budullewraagh]

yeah, well...depending on how you deal with it you may not expose yourself to dangerous conditions

[Silencer]

OMG! That thing was ridiculous! It looked like some monster was going to crawl out of the powder.

 

Why were those tentacle things formed?!

[YT2095]

you weren`t using Mercury based compounds were you? in the form of "Pharoes Snakes"?

 

or however you spell an Egyptian king/ruler type person?

 

Fair oh?

[Silencer]

It's Pharaoh, but what are you talking about? I didn't do anything, I was just talking about the video bud posted.

[budullewraagh]

and i dont take credit. if you watch it it says "copyright university of sheffield".

 

yt, it's a video of the reaction of a paste made by mercuric thiocyanate and ammonium dichromate

[YT2095]

got ya! thought as much and no I didn`t see the vid, the description was enough for me )

[jdurg]

i should add that chromium and its salts are carcinogens

 

There should be a 'suspected' carcinogen. It hasn't been conclusively proven. In fact, the human body requires a moderate amount of the chromium ion in order to help metabolise sugars. So I wouldn't go eating it by the barrel full, but there is absolutely no need to get yourself into a hazmat suit just to work with some Cr ions.

[Gilded]

"i should add that chromium and its salts are carcinogens"

 

Wasn't that the case in Erin Brockovich?

[jdurg]

I thought that was plutonium? (Only heard about the real thing, not the movie).

[Silencer]

Chromium-6 (hexavalent chromium)

[TWJian]

I once tried a 65/35 mixture(by weight of ferric oxide and aluminium before.I used labortary grade chemicals.Owing to a lack of a digital scale,Iused a triple beam 1 instead.I filled it in a flimsy, wide cardboard case( i don't want an explosion),stuck a sparkler inside with some Mg shavings for good measure,then placed it in a sandbox.The mixture ignited with a brilliant flame(i had to turn my eyes away even though i was wearing sunglasses).Sparks flew out.A residue of iron and aluminium oxide,together with some molten silica and ashes was left in the sandbox(surrounded by sand).Btw.I mixed the powder by putting it inside a bottle and shaking it for 15 minutes.

[TWJian]

the purpose of Sulpher in many Pyro compounds is to only lower the Activation energy (Heat).

 

Not nesscary that only.The oxidation of sulphur also acts as an energy source,thereby reducing the external heat needed to activate thermite compound indirectly.(the activation energy remains the same)

[Kindria2000]

OMG I love thermite!!! My friends and I are kinda obsessed with the stuff, bu its so much fun!