Magpie
lab constructor
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Registered: 1-11-2003
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Mood: Chemistry: the subtle science.
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auto-ignition temperature
I was doing some reading in an organic lab manual today when I stumbled across a very interesting footnote. It was a warning about the fact that
carbon disulfide could be ignited by a steam bath! 
I found this almost incredible so looked up its auto-ignition temperature, and sure enough, it's below 100C. Here's the auto-ignition temperature for
CS2 along with those for two other solvents that I thought would be in the same class, but obviously aren't:
CS2...................................90C
diethyl ether ..................170C
pentane..........................260C
The single most important condition for a successful synthesis is good mixing - Nicodem
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Aderyn
Harmless
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They warned especially for that in the safety manual I got for my basic organic chemistry lab course last year. I didn't get an opportunity to try it
out, but it sure cought my attention as well. ;p
Hi, btw. I've been a member for a while, but hasn't posted until now. 
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garage chemist
chemical wizard
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I can try it, I have enough CS2.
I already ignited CS2 with a glass rod previously heated in a bunsen burner, it works.
I haven't tried to ignite it with boiling water though.
Interestingly, CS2 leaves a yellow sublimate of sulfur on the sides of the beaker when it is burned. It seems to decompose in the flame.
Another flammable substance with low autoignition point is acetylene.
When a stream of acetylene is ignited at a pipette tip and allowed to burn for a few seconds, the flame will immediately re- ignite itself when it is
blown out. A cool effect.
The heated pipette tip is hot enough to ignite the acetylene.
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praseodym
Hazard to Others
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Silane and white phosphorus are also substances with low autoignition points. So would the effect be more spectacular if these 2 substances are used?
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madchem
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only thing is that White phosphorous is pretty toxic, dont mess with it
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chemoleo
Biochemicus Energeticus
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Please Madchem refrain from posting comments like this. We all know this, if we all started posting comments suchs as this the forum would be
cluttered with useless details.
To make this comprehensible to you - how would you like it if the next 10 posts dealt with the toxicity of silanes, carbon disulfide, the intoxicating
and flammability properties of ether, and so on?
So please - use your wisdom when it *really* is needed!
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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BromicAcid
International Hazard
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I thought that the first post kind of directed this thread towards solvents with low spontaneous ignition temperatures. If you go beyond that
criteria there are just too many compounds that are pyrophoric to discuss aside from silane and phosphrous so maybe we should try to stick to that.
With such a temperature that it can ignite, it seems it would have some utility in survival situations, it would be easy to acheive such a temperature
through most any friction (doubtable but imagine if you could get that kind of temperature by rubbing your hands together, neat [albeit toxic] magic
trick). A hot car on a summer day might even be able to ignite it, very dangerous stuff for a backyard chemist in the summer considering how the heat
can accumulate on objects.
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