Thermite

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Offline ATOM_SPLITTER

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Thermite
« on: 15/10/2005 05:28:33 »
Its a hard to light long burning substance which you can make out of iron oxide and alumiaum powder and my question is how and why is Thermite so hard to light when it burns so long and at such high temiture? also I've been wondering thermite is made of 3 parts iron oxide and two parts alumiaum powder what does the 'part' in each formula mean?


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Offline itsjustme

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Re: Thermite
« Reply #1 on: 15/10/2005 12:08:07 »
parts mean like percentage; 3 parts iron oxide, 2 parts aluminium. add the parts, you get 5 so each part is a fifth, does this make sense? the other question hmm... maybe you need high temprature to produce molten aluminium and start a chain reaction, just guessing.
 

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Offline rosy

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Re: Thermite
« Reply #2 on: 15/10/2005 13:19:34 »
2:3 is a molar ratio rather than a proportion by mass. For every 2 atoms of Al you need 3 of Fe. So you'd have to calculate the masses you'd need:
2 Al + 3 FeO -> 2 AlO3 + 3 Fe
 

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Offline pyromaster222

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Re: Thermite
« Reply #3 on: 15/10/2005 14:18:56 »
thermite burns so hot because iron oxide is a high temperature oxidiser and so it also needs a high temperature to start (gunpowder will not have enough heat to start thermite, you need to light it with magnesium)
the ratios will be:
2 moles of aluminium which is 2(27)=54grams to 3 moles of iron(I)oxide which is 3 (56+16)=216
so ratio is 54:216 which is 1:8 Al:FeO
this applies to black iron oxide which is different to rust (Fe2O3)
the ratio for rust is
54:160 Al:Fe2O3 thats about 3:8 and it burns rather fast too
 

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Offline ATOM_SPLITTER

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Re: Thermite
« Reply #4 on: 15/10/2005 14:43:54 »
I've also heard It be done with sulfric acid which I don't know if thats true but yes thank you all for replying! =) and Thermite is some amazing ang forgiving stuff! Thermite burns at up to 2000 degres sometimes!and you can also light it with potassium chlorate

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« Last Edit: 15/10/2005 14:47:35 by ATOM_SPLITTER »
 

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Offline pyromaster222

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Re: Thermite
« Reply #5 on: 15/10/2005 18:12:20 »
there are many different thermites such as CaSO4/Al. this is a very high temperature thermite, more so than iron oxide i believe. it's also castable but is extremely hard to light. There are also thermites with copper oxide which burn very fast (like medium grade gunpowder)
 

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Offline robotjesusbeta

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Re: Thermite
« Reply #6 on: 16/11/2005 20:57:19 »
Thermite is great Fun [:D], personally I find the best way to ignight it  *at a safe distance* is to use a drinking straw, first glue one end shut with hotglue, now fill about 1 inch with a pure thermite mix, then ontop of that fill it with 1Magnesium/1Hexamine/1sulphur and ontop of that an   inch of 2Potassium permanganate/2Alu/1Hexamine, and fill the rest of the space with some low grade black powder. now just submerger 1/2 of the first inch of the straw in your thermite, the reason I recomend the Addition of Hexamine is to slow the burn rate of the flash powder down because you dont want the straw to bang and go out hehehe. Also I was tweaking my Thermite one time and decided to substitute 1g of ALu for 1g of MG and mixed it in fully, thinking 1g isnt going to make a hell of a difference was where I went wrong, the thermite package (50G overall) ignited and slung molton slag in about a 2 metre radius. You may think this was because of the container I had it in but it was totally unconfined and ignited with MG ribbon! So just be careful with subsitution of Metal powders

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Offline Ylide

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Re: Thermite
« Reply #7 on: 17/11/2005 01:01:03 »
I've seen a thermite paste used before, it basically adheres the thermite to a surface that will be burned through, like a steel plate.   (the place I saw it used was cutting through the hull of a boat)  I'm curious what medium was used for the paste.  It would have to be something organic that would not diminish the burning properties of the thermite.  



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Offline robotjesusbeta

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Re: Thermite
« Reply #8 on: 17/11/2005 18:09:51 »
hmm i have used Silacone sealant as a binder in other pyrotechnic formulas so i would expect it would work with thermite just aslong as you used a small amount by weight i recon with a 50g batch of thermite *30g al 20g iron ox* id say start with 7g of silacone sealant possible problems are:
it will set too fast before you work out your ratios correctly
it will set before you can mix it all in
you will end up with a lump of metalic rubber that doesnt ignight

Possible improvements:
Add magnesium 2g to a 50g batch this will ensure it all ignites

(REMEMBER A thermite reaction takes less than 2 seconds to peak after ignition) with the addition of Magnesium i would say a fragment of a second but with the sealant Im thinking the 1.2 seconds scale and then  you gotta have enough to break through the hull of this boat not gonna be easy a bit of trial and error i thinks, another possible problem if you dont use enough you will warp the metal to ****

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Offline Life

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Re: Thermite
« Reply #9 on: 21/02/2006 13:16:25 »
jut a quick question..

Does thermite burn when confined? and if so, does it effect the rate at which it burns?
 

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Offline anthony

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Re: Thermite
« Reply #10 on: 24/02/2006 00:28:53 »
Yes. Thermite burns when confined as it contains it's own oxidiser (iron oxide) and fuel (aluminium). The rate would be unchanged.

The, as yet, unanswered question as to why it is so difficult to light has a simple answer, it requires a very high activiation energy. The reason it gets so hot is that the reaction is highly exothermic. Classic school chemistry concepts. Why it has such a high activation energy is that the reactants and products are actually quite stable, whereas the intermediates are very unstable and require a high energy input to form.
« Last Edit: 24/02/2006 00:31:09 by anthony »

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Offline Ray hinton

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Re: Thermite
« Reply #11 on: 24/02/2006 01:17:29 »
anthony
let me know when you intend testing your thermite,i will pop outside and see if i can catch your fly past(video camera is on charge).
its the drugs,y-know.

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Offline DrDick

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Re: Thermite
« Reply #12 on: 04/04/2006 20:17:09 »
quote:
Originally posted by pyromaster222

there are many different thermites such as CaSO4/Al. this is a very high temperature thermite, more so than iron oxide i believe. it's also castable but is extremely hard to light. There are also thermites with copper oxide which burn very fast (like medium grade gunpowder)



Are you sure you don't mean CuSO4/Al?  To convert a metal cation to the elemental metal, you need a more active metal (one that wants to be in the cationic state even more) to perform the conversion.  Al is more active than Fe, so Al metal will react with oxidized Fe but Fe metal won't react with oxidized Al.  Likewise, Ca is more active than Al, so oxidized Ca won't react with Al metal.  However, Cu is a pretty inactive metal, so oxidized Cu will react with Al metal.

DrDick

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Offline ATOM_SPLITTER

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Re: Thermite
« Reply #13 on: 12/07/2006 20:15:56 »
it's amazing what thermite can do,and how amazing it is


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Offline lightarrow

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Re: Thermite
« Reply #14 on: 09/08/2006 14:12:04 »
quote:
Originally posted by DrDick

quote:
Originally posted by pyromaster222

there are many different thermites such as CaSO4/Al. this is a very high temperature thermite, more so than iron oxide i believe. it's also castable but is extremely hard to light. There are also thermites with copper oxide which burn very fast (like medium grade gunpowder)



Are you sure you don't mean CuSO4/Al?  To convert a metal cation to the elemental metal, you need a more active metal (one that wants to be in the cationic state even more) to perform the conversion.  Al is more active than Fe, so Al metal will react with oxidized Fe but Fe metal won't react with oxidized Al.  Likewise, Ca is more active than Al, so oxidized Ca won't react with Al metal.  However, Cu is a pretty inactive metal, so oxidized Cu will react with Al metal.





You are right when you say that CaO cannot be reduced from Al; you could be wrong when you believe that, in CaSO4, Al must reduce CaO: it could reduce SO3; I have never tried this thermite, however.

About 3CuO + 2Al = 3Cu + Al2O3, I have tried it several times. If powders are very fine, the reaction is almost as quick as flash powder! Delta H of formation of CuO is much lower (in absolute value) than that of Fe2O3, for example, so the heat of reaction is Very high. Probably, some of this heat decomposes CuO producing oxigen gas, and this makes the reaction explosive. Don't confine this thermite at all!



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Offline lightarrow

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Re: Thermite
« Reply #15 on: 05/09/2006 11:34:14 »
Two days ago I made thermite with CaSO4 and Al. It really works! Before having read in more than one site that this is the right formula, I would have thought it was wrong too.
It's incredible what Al powder is able to reduce!

Assuming the reaction is: CaSO4 + 2Al --> Al2O3 + CaO + S, I added iron to combine with S (I thought hot gaseous S released could make the reaction dangerous and lose heat) , so that the reaction should have been:
CaSO4 + 2Al + Fe --> Al2O3 + CaO + FeS. I'm not sure about these equations, however; anyway the reaction was fast and very hot! I have ignited it with a little amount of normal thermite.

I used: 11.5grams of CaSO4, 4.6g Al, 4.7g Fe.
Al: fine, grey powder.
CaSO4: dried with kitchen burner.
Fe: powder.
« Last Edit: 05/09/2006 19:41:51 by lightarrow »

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Offline Mr Andrew

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Re: Thermite
« Reply #16 on: 12/09/2006 19:18:13 »
How is the Fe oxidized to combine with the sulphur(which must be reduced again to combine with the Fe)?  I don't think the Fe really does anything but then again the heat of the reaction could be enough for the reaction to form FeS to occur.

Either way it is very interesting an I think it is worth looking into more. (Yay, we've actually got a discussion on an experiment!!!)
I think I'm going to run this experiment sometime and see what happens[:)].

Does anyone know the standard enthalpy of formation of S from 6+? What about [Al]3+ from Al metal? Those figures would help in determining how much material to use to make sure it doesn't kill somebody.

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Offline lightarrow

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Re: Thermite
« Reply #17 on: 13/09/2006 07:09:41 »
Quote
How is the Fe oxidized to combine with the sulphur(which must be reduced again to combine with the Fe)?  I don't think the Fe really does anything but then again the heat of the reaction could be enough for the reaction to form FeS to occur.

Does anyone know the standard enthalpy of formation of S from S6+? What about Al3+ from Al metal? Those figures would help in determining how much material to use to make sure it doesn't kill somebody.
DeltaH°(f) FeS = -101.67
(data from:
http://webbook.nist.gov/cgi/cbook.cgi?Formula=FeS&NoIon=on&Units=SI&cTC=on&cTR=on)
so, actually, the formation of FeS releases heat.

S (that is: SO42-) is reduced from Al (it's this reaction that releases the most of the heat) and then S combines with Fe.
« Last Edit: 02/08/2007 19:58:28 by lightarrow »

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Offline Mr Andrew

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Re: Thermite
« Reply #18 on: 15/09/2006 22:21:14 »
I think I get it. Just to make sure, if you take S and Fe (that is the elements) and heat them together do you get FeS? If you do then I think it makes sense.

I think, for safety sake, I am going to run the reaction in a galvanic cell so the energy produced is in the form of electricity and that can be easily controlled (i.e. disconnecting the electrodes). Also, I think I'll leave out the Fe to make sure that SO2 is really formed (the S is reduced). I've thought about this and come up with the following equation:

2Al + 3[Ca]2+ + 3[SO4]2- --> 2[Al]3+ 3SO2 + 3[Ca]2+ + 6
  • 2-


I can't see why the S might go all the way from 6+ to 2- (the ox-state needed to make FeS) when it could stop at 4+ and make the molecule SO2 which is not extremely active and smells oh-so-wonderful. Maybe in the presence of Fe it does that, I don't know for sure.  The fact that O2 can be used from the air to mix with the Ca or Al makes all that much harder to determine the mechanism. The oxygen ions left over might form O2 molecules and reduce the S more (though oxygen is an oxidizing agent-imagine that- so I don't know that this would be probable).

Oh man, I really need to run this experiment in the lab!! Oh, that reminds me...my chem teacher needs documentation of this experiment and what should happen (kind of like a formal lab report of this reacton being run previously or a demo designed around this reaction...etc.) so he can use the school's equipment and can't be fired/sued/well, you get the idea. If he doesn't have something that he can pick up (like a book of demos) and have a procedure and materials and expected results right there in front of him he is not willing to let me do it :(.

Any help would be appreciated greatly!

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Offline lightarrow

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Re: Thermite
« Reply #19 on: 16/09/2006 08:12:56 »
quote:
Originally posted by Mr Andrew

I think I get it. Just to make sure, if you take S and Fe (that is the elements) and heat them together do you get FeS? If you do then I think it makes sense.
Yes, it's a classical experiment for high school lessons, showing the fact two different elements (Fe and S) after a chemical reaction becomes a completely different substance (Fe is not present anymore, because the compound it's not affected from a magnet anymore). You simply mix together very well 56g of Fe powder, 32g S powder, put the mix inside a test tube and then heat it with a flame. After a while, the mix becomes very hot and the reaction proceeds by itself.
quote:
I've thought about this and come up with the following equation:

2Al + 3[Ca]2+ + 3[SO4]2- --> 2[Al]3+ 3SO2 + 3[Ca]2+ + 6
  • 2-


I can't see why the S might go all the way from 6+ to 2- (the ox-state needed to make FeS) when it could stop at 4+ and make the molecule SO2 which is not extremely active and smells oh-so-wonderful.
DeltaH°(formation) SO3 = -395.77 KJ/mol ; DeltaH°(f) Fe2O3 = -825.5 KJ/mol (data from NIST); it means that, if Al reduces Fe2O3 to Fe, it reduces much better SO3 to S. Certainly we should also consider the heat necessary to decompose CaSO4 to CaO, I couldn't find it, but it's surely much less than those previous values.
I don't know what could happen in an electrolitycal cell, however.
« Last Edit: 16/09/2006 08:15:50 by lightarrow »

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Offline Mr Andrew

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Re: Thermite
« Reply #20 on: 16/09/2006 19:46:59 »
Ok, that makes sense.

[:(!]I still can't find any official documentation on the CaSO4/Al Thermite reaction so I can run it in school. Please help me!

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Offline Mr Andrew

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Re: Thermite
« Reply #21 on: 16/09/2006 19:46:59 »
Ok, that makes sense.

[:(!]I still can't find any official documentation on the CaSO4/Al Thermite reaction so I can run it in school. Please help me!

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Offline Xare

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Re: Thermite
« Reply #22 on: 21/09/2006 02:24:53 »

 This is ONE of many steel collums from the WTC.

 It has been cut by a THERMITE Shaped Charge Demolition Device.




  Please Inform yourself's

 INFOWARS.COM

  newbielink:http://www.infowars.com/articles/sept11/thermite_id_culprit_wtc_collapse.htm [nonactive]

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Offline Mr Andrew

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Re: Thermite
« Reply #23 on: 21/09/2006 03:24:58 »
quote:
Originally posted by Xare


9-11 was a False Flag Shadow Government Operation.  It was an Inside Job to set a Pretext for War.



This is a Chemistry site, not a political thread.  Yeah, so thermite's a chemical reaction, fine.  But you don't need to go further than that.  Spare the rest of us who are interested in chemistry--PLEASE!

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Offline Mr Andrew

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Re: Thermite
« Reply #24 on: 21/09/2006 03:25:28 »
quote:
Originally posted by Xare


9-11 was a False Flag Shadow Government Operation.  It was an Inside Job to set a Pretext for War.



This is a Chemistry site, not a political thread.  Yeah, so thermite's a chemical reaction, fine.  But you don't need to go further than that.  Spare the rest of us who are interested in chemistry--PLEASE!

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Offline Xare

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Re: Thermite
« Reply #25 on: 21/09/2006 04:58:15 »

  Ok more on topic

 Did you know that when you add sulfer to thermite its called thermate.

 They add the sulfer because it helps lower the melting point of steel.

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Offline lightarrow

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Re: Thermite
« Reply #26 on: 21/09/2006 08:34:42 »
quote:
Originally posted by Xare

They add the sulfer because it helps lower the melting point of steel.
It's because FeS that lowers Fe melting point forming something like Fe2S?

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Offline simpsonsman

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Re: Thermite
« Reply #27 on: 19/10/2006 21:11:26 »


1. me and my friends tried to make the rust for thermite by talking steel whoole and putting it in blench/ vinigar mix. Is this rust good enough.

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Offline Mr Andrew

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Re: Thermite
« Reply #28 on: 20/10/2006 02:19:55 »
If you just put it in water overnight it works just fine.

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Offline simpsonsman

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Re: Thermite
« Reply #29 on: 20/10/2006 03:22:56 »
so even thou we didnt use any water in the mix, we can still save it by putting it in water now?

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Offline lightarrow

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Re: Thermite
« Reply #30 on: 21/10/2006 14:39:05 »
quote:
Originally posted by simpsonsman

so even thou we didnt use any water in the mix, we can still save it by putting it in water now?
Rust is formed by the action of air oxygen on iron with the help of water.

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Offline simpsonsman

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Re: Thermite
« Reply #31 on: 22/10/2006 02:58:38 »
I Know but to make the rust we didnt use any water. We stuck steel wool in blech/vinger mix. So can we make this rust usable by putting it in water?

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Offline lightarrow

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Re: Thermite
« Reply #32 on: 22/10/2006 11:11:32 »
quote:
Originally posted by simpsonsman

I Know but to make the rust we didnt use any water. We stuck steel wool in blech/vinger mix. So can we make this rust usable by putting it in water?
What I mean is that, if you have really made rust, certainly it won't become something else by putting it in water.

By "blech" you mean "bleach" I suppose. So, even if I have never made this reaction, I suppose FeCl3 (iron 3 chloride) is formed as well, and this is not exactly rust, and it's also hygroscopic. Have you already used this kind of rust for thermite?

Anyway, as Mr Andrew said, if you put iron whool in water, better if you add a little of oxygenated water and a little bit of acid (any, vinegar it's ok) and you let it react overnight, it's ok the same.

Then, you have to dry the rust powder in a kitchen burner (or similar), however, to convert any amount of Fe(OH)3 into FeOOH or Fe2O3.
« Last Edit: 22/10/2006 11:22:09 by lightarrow »

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Offline simpsonsman

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Re: Thermite
« Reply #33 on: 23/10/2006 20:01:29 »
Well we have never used this rust before, i my friend thought that It wouldnt work becuase it was pure enough. So I just want to know can this rust be saved or should I just throw It out. And what do you mean by oxygenated water, Sorry i dont know much about chemestry

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Offline lightarrow

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Re: Thermite
« Reply #34 on: 24/10/2006 14:20:22 »
quote:
Originally posted by simpsonsman

Well we have never used this rust before, i my friend thought that It wouldnt work becuase it was pure enough. So I just want to know can this rust be saved or should I just throw It out. And what do you mean by oxygenated water, Sorry i dont know much about chemestry
Rust doesn't ruin with time. It just remains as it is, water or not water.
Oxygenated water is that solution we use as disinfectant: oxygen dissolved in water.

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Offline simpsonsman

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Re: Thermite
« Reply #35 on: 24/10/2006 20:06:42 »
Im just asking, is rust usable for thermite?

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Offline lightarrow

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Re: Thermite
« Reply #36 on: 25/10/2006 15:29:03 »
Im just asking, is rust usable for thermite?
You mean that you asked if you can use rust for thermite after having put it in water?
If this is the question, the answer is No; as I have already written: you have to remove water from rust, to use it in the thermite.

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Offline Mr Andrew

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Re: Thermite
« Reply #37 on: 02/11/2006 03:24:32 »
Simpsonsman, this is what i think the reaction of iron in bleach (sodium hypochlorite and sodium hydroxide) and vinegar would give:

12[H]+ + 6[OH]- + 6[ClO]- + 2Fe --> 2Fe(OH)3 + 3Cl2 + 6H2O

You wouldn't get much rust except what iron reacted with the water.  I could be wrong about this completely so don't take it as a truth without checking it with someone who knows more than me.
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Offline lightarrow

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Re: Thermite
« Reply #38 on: 02/11/2006 08:16:19 »
I'm sorry Mr Andrew but I have to correct you. You can't write a chemical reaction where H+ and OH- ions are present at the same time, if bleach and vinegar (basic and acid respectively) have already mixed together. After mixing, the solution is either basic or acid, depending on the amount of vinegar you added. Tipically, adding an acid to bleach gives chlorine Cl2 (so, it's quite dangerous if you breath it!) wich is more oxidizing than bleach itself.
Then Cl2 reacts with Fe giving FeCl3 and so Fe3+ (iron chlorine is water soluble) which, in turn, reacts with water, if the solution is not acid, giving
Fe(OH)3: Fe3+ + 3H2O → Fe(OH)3 + 3H+.

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Offline Mr Andrew

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Re: Thermite
« Reply #39 on: 02/11/2006 23:18:39 »
Wow, thank you lightarrow.  I should have caught that.  Yup, ferric chloride would form then.  That might run a thermite reaction but I wouldn't trust it to be entirely safe.  Anything with chlorine in it and very high temperatures should be regarded as dangerous (Cl2 gas is not pleasant to say the least).

I'm not positive about this but when iron reacts with oxygen in the presence of an water (or H+ ions more generally) Fe+3 ions form and O-2 ions combine with the H+ ions to make water.  This then reacts to form Fe2O3 or rust.  If Fe+3 ions could be made more quickly than by reacting iron directly with oxygen, in the presence of water, rust could be made to form more quickly.

As I understand it, H2O2 in the presence of protons is a very good oxidizing agent.  Would it be possible to put iron in a solution of peroxide and an acid like vinegar and get rust more quickly than in just plain old water?  If so, this would be better than leaving iron in water overnight because it would happen much more quickly.

The half reactions would look like this:

3(2e- + H2O2 + H+ --> 2H2O)
2(Fe --> Fe+3 + 3e-)
« Last Edit: 04/11/2006 20:08:15 by Mr Andrew »
--Life is the greatest experiment that any person will ever conduct.  It should be treated with the same scientific method as any other experiment.

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Offline lightarrow

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Re: Thermite
« Reply #40 on: 03/11/2006 14:38:14 »
Everything correct. You have won a prize!
Remember however that every reaction involving iron in water solution is affected very much from the value of pH .

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Offline Mr Andrew

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Re: Thermite
« Reply #41 on: 04/11/2006 20:05:43 »
Yay!!! [;D], What did I win?!? [:P]

When you said reactions of iron in water are affected by pH, am I right in saying that if the pH is too high, Fe(OH)3 would precipitate?  It shouldn't matter if it has a low pH, right...unless the conjugate base of the acid is insoluble when combined with Fe3+ ions.  But then again, if it was generally insoluble, it wouldn't be a strong acid and wouldn't lower the pH much.  I believe acetates are genereally soluble so it wouldn't really matter too much if vinegar was used.

So, simpsonsman, if you put roughly 1 part iron wool in a solution of 4 parts vinegar and 1 part peroxide (by mass, of course) you should get some rust fairly quickly.  This should be dried before use in a thermite reaction.  I must caution you about thermite: it creates temperatures hot enough to melt the iron produced and the aluminum powder needed is very dangerous.  I'm sorry to say, only a licensed chemist should try to run a thermite reaction because of the safety issues.
--Life is the greatest experiment that any person will ever conduct.  It should be treated with the same scientific method as any other experiment.

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Offline simpsonsman

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Re: Thermite
« Reply #42 on: 07/11/2006 21:07:15 »
WOW, so you need iron wool for the rust, or will steel wool work?

 Is this rust i have useful or should i throw it out?

Can you make rust by burning steel wool with an electrical current?
why talk when you can fight

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Offline daveshorts

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Re: Thermite
« Reply #43 on: 08/11/2006 12:18:01 »
The only thing I would worry about if you were buring steel wool (apart from safety obviously) is that you are quite likely forming FeO rather than Fe2O3 - FeO tends to be black rather than brown. And this will have less oxygen to react with your aluminium.

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Offline lightarrow

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Re: Thermite
« Reply #44 on: 08/11/2006 12:55:11 »
Yes. However is good the same for thermite. They say the best is Fe3O4. There isn't however a big difference from thermite made with FeO, Fe3O4, Fe2O3, providing that it's used the right stoichometry (I'm not sure this is the correct translation).

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Offline lightarrow

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Re: Thermite
« Reply #45 on: 08/11/2006 13:13:34 »
Yay!!! [;D], What did I win?!?
You won a cool reputation!
Quote
When you said reactions of iron in water are affected by pH, am I right in saying that if the pH is too high, Fe(OH)3 would precipitate? It shouldn't matter if it has a low pH, right...unless the conjugate base of the acid is insoluble when combined with Fe3+ ions.
Ok.
Quote
But then again, if it was generally insoluble, it wouldn't be a strong acid and wouldn't lower the pH much.
For the special case of Fe3+ this is almost always true; in general it's not true: AgCl, for example, is insoluble, but HCl is a strong acid.
Quote
I believe acetates are genereally soluble so it wouldn't really matter too much if vinegar was used.
Yes, however acetic acid, or acetates in general, as organic substances can be oxidated by strong oxidizing agents, especially if these are in high concentration and with very low pH.

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Offline simpsonsman

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Re: Thermite
« Reply #46 on: 03/12/2006 19:46:03 »
is it true that batery acid mixed with sugar makes a thermite like reaction?
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Offline lightarrow

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Re: Thermite
« Reply #47 on: 05/12/2006 12:35:09 »
is it true that batery acid mixed with sugar makes a thermite like reaction?
"Thermite like" not at all. I know that concentrated sulfuric acid with sugar makes a vigorous exothermic reaction, which gives a black solid mass which grows quickly and comes out of the container, but I don't think diluted sulfuric acid (=battery acid) could give something of that kind. If you concentrate it, it's another story...

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Offline moonfire

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Re: Thermite
« Reply #48 on: 05/12/2006 13:22:37 »
Whew!  that is a good thing..hehe...Hiya Alberto...miss you much...
"Just Me, Lo" Loretta

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Offline lightarrow

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Re: Thermite
« Reply #49 on: 05/12/2006 15:37:19 »
Hello Loretta! A kiss and a hug to you!
Have a good day!
P.S.
(I hope your comment on my previous post it's not what I think!)
« Last Edit: 05/12/2006 15:41:13 by lightarrow »