School demonstration of a thermite reaction.

"This demonstration shows the highly exothermic reaction between aluminium and iron (III) oxide that produces molten iron. This is a competition reaction, showing aluminium to be a more reactive metal than iron. A redox reaction takes place." (explanation from the Nuffield Foundation)

The set up consists of a mixture of fine aluminium powder (3g) and (importantly) dry iron (III) oxide (9g). For safety, this was mixed just prior to the demonstration (this stuff is highly explosive and therefore dangerous-it must not be mixed with a metal spatula).

The mixture was poured into a small conical shaped filter paper holder which was held above a large Pyrex beaker by a triangular clay pipe holder (an up-to-date method uses a large plastic beaker but we have been using this one for years). The beaker contained a large 12cm+ sand layer topped with a 5cm water layer.

The 'fuse' used here was a standard sparkler.