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View Full Version : Yay my first successful experiment/irresponsible attempt!


nmbookworm
2009-01-01, 07:54
Haha this is going to sound so lame to you guys but i thought id share just so i might find out what happened and why it happened.

It was last night (NYE) at my mates place and i wanted to celebrate with something cool. Originally I wanted to ignite some ammonium nitrate that i obtained but i dont have the knowledge or experience yet. So, we ended up making our first smoke bomb out of potassium nitrate. It was awesome.

First, we made a small one. Using potassium nitrate, sugar and baking soda. Ill post the method if anyone is curious because its super easy, easily found on youtube as well. And its possible to get potassium nitrate even here in Australia which is alot more strict than the states in the sale of chemicals.

Anyways I was just curious as to what scientific explanation can be given for the whitish and purple flames that seemed almost like a furnace. The first one we made was perfect, lots of smoke, however, in the second one we used five times as much of the proportions as we did before. But, as we had been drinking a bit as well we forgot to add the baking soda. Even after we realised we still lit it and this time there was still a ton of smoke but it burned so much faster and bigger and there was lots of awesome purple and white flame. Oh yeah, and there was about 30 crushed sparklers in the middle as a fuse, coz i have no idea how to get fireworks fuse. Any clarifying reasons for why things happened? Id like to keep trying it out, so I can make bigger and better ones, cheers.

asilentbob
2009-01-01, 12:11
I could go into a lengthy explanation... but I'll try to make it short as its 6am here... I need to sleep.

Potassium's flame spectra is a purpleish whiteish color. When you have alot of sodium present flames are going to be usually washed out yellow. The more flames the less smoke produced to an extent. Try a choked (nozzled) smoker in a paper tube. The choke will prevent some of the oxygen in the atmosphere getting to the mix meaning a little less flame. Your not wanting a rocket or fountain here though, so make your nozzle appropriatly. You might want to look into adding some solid parafin wax into the mix, not a ton though. Your goal is no visible flame outside the choke as the atomized parafin vapor coming out can be pretty flammable... and if its igniting and burning your loosing possible smoke particles.

If you add wax, tweak your ratios, and get your choke system down good you will get a very nice smoker. One I believe frogfot did was a paint can with a good deal of smoke mix + parafin wax particles inside, then the lid on tied down, but with enough holes poked in it so that it wouldn't blow off.

Mokothar
2009-01-01, 15:30
First off: ammonium nitrate isn't combustible. If you burn it, it will decompose into water, NOx and N2O.

Fuse is relatively easy to make, since you've got access to potassium nitrate.
Try looking up "blackmatch"

Sentinel
2009-01-01, 20:07
baking soda doesn't burn. At high temps it will decompose into water and sodium carbonate, but it actually retards burning. It's in many chemical fire extinguishers. And you can throw it on a kitchen fire.

warweed12
2009-01-02, 09:16
baking soda doesn't burn. At high temps it will decompose into water and sodium carbonate, but it actually retards burning. It's in many chemical fire extinguishers. And you can throw it on a kitchen fire.
that is exactly the point it does not stop the burning but rather in the right amounts slows it down ...

MH-iforgotmypassword
2009-01-03, 08:05
that is exactly the point it does not stop the burning but rather in the right amounts slows it down ...
Exactly.

And the reason the second one was so hot was because there was a lot of fuel (sugar) and oxidizer (KNO3) all right there, with none of the baking soda to keep it slowed down (and thus more smokey. Really hot fires (of carbohydrates) produce all CO2+H20, which are clear. You need a cooler sooty fire so that little particulates get in the air.