This demonstration illustrates the principle behind a grain elevator explosion. Grain dust, like lycopodium powder, is not especially flammable, but when grain is dumped into a grain silo, some of the finer dust particles can remain suspended in air surrounded by oxygen. This mixture can be ignited by a spark, resulting in an explosion.

Lycopodium powder is a fine yellow powder derived from the spores of lycopodium clavatum (stag's horn club moss).

This video includes voiceover:
Lycopodium powder is placed in the top of a funnel mounted inside a large can. A lighted candle is also placed in the can. The cover of the can is firmly pressed into place. Air forced into the funnel causes the powder to disburse within the can and to be ignited.

Chemistry Comes Alive! Volume 7 > Dust Explosion in a Metal Can

CCA! volumes are organized according to topics in chemistry. Some movies are included on more than one volume of CCA! because they can be used to demonstrate more than one topic or idea.
 

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