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ArcticMyst Security by Avery

Match in closed container

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There have been a few discussions on whether lighting a match in a closed container will create low or high pressure... I decided to try it myself.

I stuck a match inside a plastic container. If the combustion created a vacuum, the heat and low pressure would cause the container to melt and shrink. If the pressure is high enough, the lid would pop off...

Here's a video of what happened.

[The video may not be immediately available as it is still "processing" on youtube.]

[media]http://www.youtube.com/watch?v=hjIICtSFXc8[/media]
 





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cool video, I lit about 20 matches in a water bottle and it just pressurized a bit..well a lot ;D
 

diachi

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only reason the pressure rises is due to the increase in heat IIRC .

-Adan
 
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Diachi said:
only reason the pressure rises is due to the increase in heat IIRC .

-Adan

I think what happens is the chemicals in the match head combust and turn into gas, which takes up more volume than solids, and the heat makes the air and vapors expand which creates a higher pressure inside the container.

:)

So it is not a vacuum.
 
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Diachi said:
only reason the pressure rises is due to the increase in heat IIRC .

-Adan

It is actually because of the quickly expanding gasses when the match lights ;)
Like igniting gun powder.. you know like in a bullet cartridge ;D ;D ;D ;D ;D
 
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Diachi said:
only reason the pressure rises is due to the increase in heat IIRC

Agreed.
Try it in a plastic bottle, it will expand due to the heat of the flame but when the match goes out it will crumple, seen it on youtube I think
 

diachi

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It's the only explanation anyway, since the chemical mass inside the container stays the same.

-Adam
 
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Well yes, but only partially. I don't think heating up the air alone creates that much pressure. The expanding gasses from the match AND the air creates the pressure.
The chemical mass may stay the same but the volume will still increase.
 
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Diachi said:
the chemical mass inside the container stays the same.

-Adam

The weight will remain identical to before combustion. The volume, however, will increase. This is only partially due to heat.
 
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Cyparagon said:
[quote author=Diachi link=1224274692/0#6 date=1224281548]the chemical mass inside the container stays the same.

-Adam

The weight will remain identical to before combustion. The volume, however, will increase. This is only partially due to heat.[/quote]

Agreed.... and mostly due to rapidly expanding gases...  ::) else a bullet would not work  :cool:
 

artix

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What type of laser is that?

(It looks like a spyder or a spartan)
 
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Artix said:
What type of laser is that?

(It looks like a spyder or a spartan)

No, I'm not wasting $1700 on something with "wicked" engraved on it... I dislike that word... not just the company.

It's my G105 (guts of an X105 in a Galileo) with a lens cap I made.
 
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being in an enclosed case like that, it seems to have the same characteristics of modern gunpowder.

gunpowder when poured on a flat surface outside, will burn pretty slowly... in a closed space, well you know.
matches are possibly the same
 

Benm

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I'm a chemistry graduate, perhaps i can shed some light on it:

The reaction of the match head when ignited results in both solids reacting to gasses (H2O, CO2, SO2), and in heat. Both contribute to the pressure created. If the vessel is strong enough to withstand the pressure, it will cool down to room temp after a while but still be at higher pressure due to the CO2 and SO2, whilst H2O has then condensed to a liquid.

If you use a plastic bottle or something with a cap that doesnt form a total seal against over-pressure, after the reaction some of the gasses will be released. When things start to cool down, the bottle is crushed by atmospheric pressure. Since the bottle holds a partial vaccuum by then, its likely any loose stopper would be sucked in thighly at that point. This is the source of any confusion about under- vs over pressure after the reaction.

gunpowder when poured on a flat surface outside, will burn pretty slowly... in a closed space, well you know.
matches are possibly the same

Match heads are similar to gunpowder, but the rate any explosion travels to them is so slow they will not really explode like gunpowder does when compacted. A container might explode due to the pressure build up as described above, but that would be similar to, for example, putting dry ice in a coke bottle (DONT).
 
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Match heads are similar to gunpowder, but the rate any explosion travels to them is so slow they will not really explode like gunpowder does when compacted.

I still have a 4" brass cannon that I fabricated in 7th grade... It uses cardboard
match heads as the gunpowder to fire a 3/8" steel ball bearing.
At 6 feet it will go through a 3/4" sheet of plywood... :eek:
I think match heads burn quite fast when compressed... agreed... not as fast as
today's black gunpowder. ;)
 




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