How to Make an Ammonium Dichromate Volcano

Learn how to make the "Vesuvian Volcano" classic High School chemistry demonstration with Ammonium Dichromate.

Materials Needed

Q: What chemical do I use to make a volcano? "When I was in the 7 - 8th grades in school about 40 years or so ago, one of the other students made a volcano for a science project. He made a chicken wire frame covered with papier-mâché and then a layer of Plaster of Paris. He had incorporated a small frozen orange juice can in the top into which he placed an orange colored chemical (it was in small crystals). He put a small amount of lighter fluid onto the crystals and lit it. When the chemical began to burn it made some smoke and LOTS and LOTS of a kind of greenish/gray ash, which flowed down the sides of the volcano. Would you know what the chemical was that he used? And if so does Skylighter have it available? I would like to make one of these volcanoes to show some friends."

A: The chemical is ammonium dichromate, and of course we have it. Who do you think we are? My favorite way of using these is at night, so you can see the bright "lava" rolling down the sides of the volcano.
The closest thing to approximating a real volcano that I can come up with is to add about 15% coarse charcoal (36 or 80 mesh) to the ammonium dichromate. Then, as described above, just light the thing. It is quite easy to light; you don’t need lighter fluid, though I do always use my trusty Bernzomatic propane torch, to keep my fingers away from the conflagration. This is a good daylight or nighttime project. And kids love 'em.