Thermite Reaction.

A thermite reaction is basically iron oxide (rust) reacting with aluminum to produce molten iron. The reaction is initiated by the heat from burning magnesium ribbon which is placed in the iron oxide/aluminum mixture, this is the fuse! (Any heat source can be used to start the reaction but it needs to be very hot as magnesium burns at about 650°C (1200°F) A sparkler may work but I have not tried this.)

Because it is spectacular and simple this my favorite reaction!

This reaction is highly exothermic and produces molten metal at about 3000°c.
Water should not be used to extinguish the reaction, since addition of water to hot iron produces potentially explosive hydrogen gas. Enjoy the pictures below:-

(Click on any image below for a bigger picture)

The mixture of
rust and aluminum
(we found 50/50 works well, Not weight!)
Ready with the magnesium fuse
and 2 sheets of 3mm
steel under the flowerpot
John lights the fuse....
There goes the magnesium
getting it up to temperature
to start the reaction


Burn baby
Burn, burn
Yeah thats about 3000°C,
it's melted through the sheet steel


Still glowing red hot
Not surprising really
And it's actually welded
the Steel together!


The Science Bit:-

This works because the thermite mixture is aluminum powder and iron oxide (rust) powder. When the mixture is heated, it starts reacting: the aluminum is more reactive than the iron, so it "pinches" the oxygen from the iron to make aluminum oxide and iron.

A balanced equation for the reaction is:-

Fe2O3 + 2Al --> Al2O3 + 2Fe


Thermite reaction video




This experiment is potentially dangerous; assumes no legal liability or responsibility for the use or misuse of the information contained on this page.

This experiment is listed for information purposes only and should only be conducted by qualified chemists who are aware of proper chemical and apparatus usage. Safety precautions such as the use of goggles, aprons, gloves, and so forth are assumed.

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