Sciencemadness Discussion Board

Coloring firworks chemistry demo

Thohan - 19-10-2006 at 20:55

Recently I have been assigned the task of getting the fireworks demonstration that the chem club that I am a part of to produce a color other than white. In our demonstrations we tape up an erlymier flask and burry it up to the head in sand. In the flask is a mixture of smokeless powder, pyrodex powder, magnesium powder, aluminum powder, and iron powder and is set off by sending a current though a wire that is placed in the flask. I have done some searching and found what chemicals are used to make normal fireworks produce color and have tried removing the metal powered and replacing it with the other chemicals but to no avail (the pyrodex and smokeless powder ignited but nothing was ejected from the flask). Sense than I have been thinking that I might remove one of the metal powders and see if that works but I though I would come here first and see if anyone knew if I was going in the right direction or not or if anyone knew how to do what I am trying to do. Thanks.

YT2095 - 19-10-2006 at 23:53

for a start you`de be better off using flash pots or metal crucibles on the sand, rather than a flask under it.
if the mix did burn you wouldn`t see it, only the smoke it produces, it`s the Flame you need to see.

as for the color mixes you have quite a bit of freedom, you can dope the oxidiser or the reducer with your color ion, and avoid Sodium Ions at all costs, unless you Want every single color to be Yellow:o

woelen - 19-10-2006 at 23:58

For really extensive fireworks knowledge, look over here:

http://groups.google.nl/group/rec.pyrotechnics

Search with keywords like strontium, barium, lithium, copper (red, green, brickred, green/blue).
There is a lot of info over there and there are quite some experts over there.

The_Davster - 20-10-2006 at 04:03

Or if you do not want to mess with all the solid oxidizers and fuels to get the colors you want, you can just pour alcohol on a pile of the salt you want the color of and light it, it is the simple way.

Thohan - 20-10-2006 at 05:38

Our fireworks demo sends the sparks up out of the top of the flask and what i am really trying to do is get the color of the sparks to be something other than white.

12AX7 - 20-10-2006 at 06:43

Sparks tend to be burning metal, something notoriously difficult to color.

If you want to get absurd about it, you could use strontium, barium, sodium and potassium metals to get the corresponding color as burning sparks. But...er yeah...

Tim

YT2095 - 20-10-2006 at 09:43

colored "sparks" are easy enough, you just need to make Micro stars, a dextrin binder and an extruder (or even a potato ricer will do), the ignition/lifting charge can be Pyrodex then :)