Australia's Science Forum

What's the prac using iron oxide and a ceramic plant pot? My senior Chem teacher wants to do a special demo for the end of year Year 11 students. Is it exothermic?

Sounds like a thermite reaction with Aluminium powder and Iron oxide powder . Start it off with a bit of magnesium ribbon .

The plant pot got me confused! I had a teacher who used to use the small tuna cans - emptied out, of course. They were just the right size and were disposable. It was also good seeing what the thermite did to the can. Sit the can on a tripod which was placed in a metal tray filled with sand.

That sounds like a great way to demo it Merilyn .Can imagine the melting hot thermite dripping out the bottom of the tuna can

The ceramic planter pot method .... you fill it with sand .... dry sand
Sand helps contain the heat from the reaction .... safety thing , like the ceramic pot . You could just put it in an evaporating basin but it will likely heat up and crack .

Sand must be dry . Aluminium powder doesn’t like being wet . And wet sand doesn’t like suddenly becoming very hot .

The Thermite mix is mounded up in the middle of the dry sand with a magnesium ribbon wick is lit .

So you’ll get bright light and flames . A few shooters out a meter radious . Best to do it on a concrete area or other non flammable space . Several meters from the spectators . I’d recommend 5 meters minimum ..... with safety googles .

Thats with about 20-50 gms of thermite.