[andy08]

Recently a couple of my friends and I were assigned the task of figuring out what happens when flour is burned.  Upon first couple tries we knew ways to make it do nothing, but as we all knew, flour mixed with fire and oxygen will cause for a nice little fire, when we told our teacher she showed the class a movie, and in the movie it talked about an experiment.  HERE IS WHERE I NEED YOUR HELP?!!!

we are trying to figure this out just to entertain the really young kids on our street (6 and 7 year olds) we have adult supervision and permission to do this, so i need everyone's help, what would be some cool tricks for us to do with pyrotechnics to entertain these kids, we are trying to figure out how to make flour ignite inside a PVC pipe, and make a flame come out the top, 20 attempts 1 success and we're not sure what we did differently. If you know how to make that work, or anything along those lines please let me know.

[Mitch]

It's a surface area issue. A clump of flour burning on a desk isn't cool. But, if you took the same clump threw it into the air and lit it, it should have a nice fireball effect.

[enahs]

Cheap'o powdered coffee creamer works much better.

And as Mitch said, it is easier and a good show to just throw it.

As for the PVC pipe really it is all about having plenty of air around it, and the PVC pipe limits that and also makes it harder for it to spread.

[constant thinker]

This wikipedia article talks about the flame test. The gist of it is, you add a metal salt to a flame (like what a bunsen burner produces), and admire the colors.

[Edit] I decided to edit out a section. I decided Mitch's idea was good, and mine may be pushing it for what you want to achieve.

[Kenichi]

To demonstrate how surface area affects burn rate, you can take the flour (as mentioned before, coffee creamers work well.  I also found that a 50:50 mix of flour and corn starch produced favorable results) and put it a the bottom of a coffee can.  A lit candle is placed at the bottom of the can as well.  Previously a small hole is cut near the bottom on the side of the can.  A small tube is fed a short ways (approx 1.5 inches) and then modeling clay is used to fill in the holes around the tube.  Attached to the outside end of the tube is some sort of squeeze bulb.  When you squeeze the bulb, air rushes through the tube, kicking the flour/creamer/cornstarch into a cloud and allowing it to burn quickly.  If performed with a top on the can, it will get blown off with a nice little boom.  If done without, flames come from the top.  Not exactly lycopodium powder or anything, but still produces a nice effect.

[Kenichi]

some other fun pyro projects...

The "burning dollar" would be sure to impress some kids.  A 50:50 mix of 97% isopropyl alcohol and water is prepared in a beaker.  The dollar bill is dunked into the beaker and  pulled out.  You might want to use tongs for that bit.  And then you can light the dollar in a candle/lighter.  The bill will flare up for about 3 seconds and then the fire will disappear and the dollar left unscathed.  The water absorbs the heat as it evaporates.  Kinda nifty.  You can also play it up and make kids think that soaking the bill in the water will do nothing when in reality you have switched the beaker of water with the one with alcohol in it.  Shouldn't be too hard to impress the young'uns

Another cool demo is to take lighter fluid or some other colorless fuel that is lighter than water and put some in beaker/flask containing water.  Do this before the kiddies show up and they will think teh clear liquid is only water.  The fuel floating on top can be set alight with a match.  Yeah, its always kinda neat to see water "burn".  hopefully those are of some help to you.

[Borek]

Not exactly lycopodium powder or anything

Collect resin from some pine tree trunk - old and dry is the best, otherwise you have to dry it by gently heating. Grind to powder. Enjoy

[Borek]

http://www.angelo.edu/faculty/kboudrea/demos/lycopodium/lycopodium.htm