Spontaneously-Combustible Flour?

Well, I know that if you put finely powdered stuff, like flour or sawdust, it has a chance that a spark will form and create a huge (and I am talking HUGE) fireball. Watch this video (those stupid kids):

The above video amuses me: They state do not try this at home, but they apparently did. They obviously didn't know what they were doing, because if they had, they wouldn't have risked their friend (or at least severely burning him).

Does anyone know the percentage chance that this will happen if, say, I took a cup of flour and use a shaker (or just a shaking motion) to spread it out into the air? If I wanted some flour to combust, would I be better off (not in health, in entertainment) to just use a match?

Oh, and yeah, I am 13, but I am a bit more mature than other people I know that are my age. I'm glad they don't know about this site, because if they did, they would already be . (Seriously.)

Thanks in advance!

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mudrunner11110 years ago
Depending on weather conditions and grounding involved static electric charges can be enough of a spark to ignite the air fuel mixture. Earler John had responded with a consideration about how water does not burn. I agree that it in and of itself in the H2O state it does not burn, but when it is seperated into it's original components of hydrogen (which Burns) and oxygen (which Supports combustion) you can and will have a very interesting (and DANGEROUS) fire! This change can be caused by a super heated fire that in a moment changes water into two seperate elements and bang! People have had fun but others have received serious pain and life long injuries or death. Please be safe and if you do not know what you are doing leave it alone.
Water isn't flammable- in the sense you mean. As it is a combustion byproduct energy would have to be used to sever the hydrogen bonds- more energy than would be obtained by combusting the byproducts. Think of this. If you electrolyze water to obtain 2H2 and O2 then burn them, it takes more energy to split the bonds than energy that is gained by oxidizing hydrogen. It's a basic law of science. So basically, the so called "superheated fire" you speak of does not gain energy, as it loses it through heating and severing bonds. If that were even to work. Magnesium and certain other materials can sever hydrogen bonds of water to use an oxygen atom for combustion and leaving a hydroxide ion. It still takes energy to sever the bonds, so it doesn't count. And before somebody mentions throwing water on an oil or grease fire- it does not combust. The water simply affects the surface area of the substance but unless the fire is being starved of oxygen energy will be lost through heating the water to vapor. So you're kind of correct.. but you're not. (don't take it hard, eh?)
Oh btw, you can do this with most finely powdered things. I load the barrel of my air cannon with sulfur and fire it over a fire. The stench is..bad.
KentsOkay10 years ago
I did something similar. Take a 4" pipe, that is 4ft long and hang in a vertical position over a large candle, so that the candle flame burns inside the pipe but still has oxygen flow. Wearing gloves and glasses, use a sifter to lighlty sift the flour down the tube, with the candle lit and keeping your face away. If dne just right, the flour will ignite and produce a saticfactory bang and flame. I have only been able to do it once out of numerous attempts. I'm only bothering telling yu this because you are definetly mature for your age. If you ever make any Instructables on the subject of bangs and flames, add them to my group, the Intergallactic Brotherhood of Bomb and Weapon Masters. Good Luck
Here's a slightly safer version--if you take "safer" to mean "standing farther away".
Mr. Wizard (search Google) did that with a paint can!
I know who Mr. Wizard is...I have one of his books!
Bran (author)  KentsOkay10 years ago
That sounds interesting. And on the "you are definitely mature for your age" part, well, my sister is a nurse in the burn unit at the local hospital so I here of so many injuries all the time. She just recently received a 7 year old boy from some other county who has locked himself in his bedroom and was playing with matches. His mom heard him screaming, but by the time she got his locked door open, he was already engulfed in flames. He almost died yesterday, but he could still die. So, I know of the dangers. Same with people driving fast/drunk/stupidly. My aunt died in a car crash. The list goes on....
. A half-a-cup of flour, fine sawdust, etc, flung over a camp fire, has an effect similar to the video, just a little more "intense." The stuff will flash back at you if you don't throw it hard enough, so be careful.
In 8th grade, there was a movie we saw in science class. where an explosives expert demonstrated the same thing. I've tried it, with no success.
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