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Thermite

Thermite

Thermite is a dangerous chemical substance that was, and still is, used to weld railroads together among other things.  It is actually one of the primary ingredients in "incendiary devices."  It was used in grenade form during WWII to disable artillery since it melted the metal down making it impossible to use, while being much more stealthy than typical explosives. 

This information is intended for informational purposes only and by viewing this page you agree to the terms set forth in this disclaimer.  DO NOT try to make or use thermite, it is extremely dangerous.   Seriously, just don't do it - a thermite reaction is irreversible (it can't be stopped once it starts) and creates liquid metal at temperatures of 2500°C or 4500°F.  To see an example of how dangerous thermite is, just watch the video below.

All of that being said, a thermite reaction is extremely cool to watch, and thermite is actually really easy to make.  Just for an example, if you had enough thermite on a car hood on the beach - the thermite would melt through the hood, through the engine, and would actually turn the sand below into glass.  The reaction really is that exothermic.  Below is a video of a couple of thermite reactions.

The reaction occurring is

Fe2O3 + 2Al 2Fe + Al2O3

The change in enthalpy of this reaction

 ΔH=Σ ΔH(products) - Σ ΔH(reactants)

is about -850 kJ/mol, which is extremely exothermic - meaning it releases a lot of heat.

 

As you can see from the reaction equation above, thermite is just a mixture of powdered Iron Oxide and powdered Aluminum.  Iron Oxide (Fe2O3) is also known as rust, and aluminum is just what you think it is - aluminum foil.  Thermite is actually quite stable at room temperatures, so mixing the proper amounts of the ingredients is safe to do.  I'm not going to tell you the weight ratios, but they can easily be calculated using stoichiometry.  Thermite can't be lit by normal means like a butane lighter - instead something that burns very hot must be used.

The easiest thing to use is a long strip of magnesium metal.  One end of the metal goes into the thermite, and the other end is lit while stepping well back and putting on some UV sunglasses.  A thermite reaction releases a large amount of dangerous UV rays.  Another method to light thermite is to use a regular red-tipped match.  The tip is buried in the thermite and the tipless side of the match is lit.  The chemicals in the tip burn very quickly, and hot enough to start the thermite reaction.

Keep in mind that mixing water with a thermite reaction causes a phreatomagmatic explosion - spewing molten iron everywhere.  To see an example of this, watch the video below - an excellent example of how dangerous thermite can be.

 

Again, this information is meant for informational purposes only.  Do not attempt to actually make or use thermite.

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