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Author Topic: Making thermite  (Read 2832 times)

Offline killfire

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Making thermite
« on: 13/05/2006 20:16:55 »
I have a question. I am using a technique to get rust which i have seen all over called Electrolysis with Iron Anode.
1: Cut the output (smaller, round) plug off of a typical AC adapter that provides a DC output. Separate the two wires in the cord and strip each of them, exposing about 2 inches of wire.

2: Fill the glass jar with warm water. Add the salt and stir until the salt has dissolved. The salt allows the water to conduct electricity.
 
3: Place the unwrapped ends of the two wires into the water, not touching each other. Plug in the AC-adapter. There is a risk of shock, even though the AC-adapters generally uses 6-12 volts, they can have high current. One of the two wires will start to bubble more than the other. This is the negative wire (-). What is occurring with the two wires in the salt water is water electrolysis. In this reaction ( 2H20 -> 2H2 + 02) water yields hydrogen gas and oxygen gas. The hydrogen gas forms at the cathode (Water Electrolysis experiment), and because 2 molecules of hydrogen gas are formed for every molecule of oxygen gas, this wire will bubble more. It is a good idea to mark this somehow so as not to forget; if the wires were to be reversed later, the end result would be rust acid instead of rust, which won't be very helpful.

4: Wrap the positive wire around the large iron nail. Drop the nail into the jar, not touching the submerged negative wire. Attaching the nail to the cathode ( (-) wire ) only results in the oxide formation on the copper wire.

5: Now, leave this as is for about 10 hours. A good amount of rust should form on the surface of the water, the bottom of the jar, and on the nail. Shake it off the nail and repeat until a generous amount of rust is formed.

6: When enough rust has gathered, drain the excess water and spread the rust on a metal pan or sheet of aluminium foil in a warm or sunny place to dry. Once it is dry, scrape it off the pan or foil and crush it into a fine powder, and the rust is ready.

The question I have is, when I start to rust the nail I get a bunch of green stuff falling to the bottom and I dont see any rust. What is the green stuff and how do I filter the rust out of it? Thanks for the help.


 

another_someone

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Re: Making thermite
« Reply #1 on: 13/05/2006 21:28:09 »
I would advise care.

If you are electrolysing common salt solution, you will get chlorine gas off one of the terminals, not oxygen.  In case you need reminding, chlorine is toxic, and was used in some of the early gas attacks in WWI.

The green deposits may be iron chloride.

http://en.wikipedia.org/wiki/Ferric_chloride
quote:

Iron(III) chloride, generically called ferric chloride, is FeCl3. The color depends on the viewing angle - by reflected light crystals appear dark green but by transmitted light, the crystals are purple-red.



Also, ferrous chloride (FeCl2) tetrahydrate is also green.



George
« Last Edit: 13/05/2006 21:42:37 by another_someone »
 

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Re: Making thermite
« Reply #1 on: 13/05/2006 21:28:09 »

 

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