Cold Fire

[aj47]

Anyone know of a chemical that burns at such a low temperature as to not burn you so you could quite literally set yourself alight. Don't worry i'm not planning anything of the sort but I just heard some talking about something similar.

Anyone know what it is if it actually exists?

[Bio-Hazard]

Are you inquiring as to a physical flame that exists such as a flame that comes out of a lighter, but is at such a cold temperature that it couldn't burn you when you touched it?

[Cap'n Refsmmat]

The reason there are flames is because the air is hot. If you make it burn too cool, then there will be no flames.

[RyanJ]

The reason there are flames is because the air is hot. If you make it burn too cool, then there will be no flames.

 

I agree with that

 

If you meant burn as in oxadise though then a lot of things will... mix just about anything with Fluorine even at low temperatures and it will "burn" - Flurine is nasty stuff...

 

Cheers,

 

Ryan Jones

[woelen]

There is a mix, which gives a relatively cold fire.

 

A mix of carbon disulfide and carbon tetrachloride (appr. 1:1 by volume) burns with a fairly cool flame.

 

In the past, magicians sometimes used this mix. They spilt it on their skin and lit the mix. The flames did not burn them, although they still feel quite hot. But with some motion the heat is bearable.

 

Nowadays, this mix is not used anymore. Both CS2 and CCl4 are toxic and the latter has a nasty long-term effect, it is a potent carcinogen. Using CS2 only is too dangerous. It burns with a much hotter flame and cannot be used without severe burns.

 

Another nice redox reaction, which gives a kind of 'flame' is to lead vapor of phosphorous through air. I have some red phosphorus (Yes, in the Netherlands this is legal ) and if this is heated in a test tube, then light-emitting clouds (flame-like) can be observed. These are cold and are due to oxidation of phosphorus vapor by oxygen.

[Halash]

the color and redness from a flame is from the air becoming so hot that it emits wavelengths in the visible spectrum. air around you has no color becuase it is not hot enough, blue flames are very hot, hence they are higher on the electromagnetic spectrum.

 

its alot like heating steel or iron till its red hot.

[DukerX]

I was under the assumption that hte color observed in combustion of carbon based fuels are due to soot particles inside the flame being heated to a red-hot temperature and thus radiating the heat energy in the visible spectrum.

Also, I think for normal "air" to glow or radiate in the visible spectrum, it had to be ionized.

 

 

-DX-

[Lance]

Air becomes ionized if it's heated enough.

[AzurePhoenix]

And certain materials will burn with different colored flames, usch as copper compounds burning blue-green, thallium green, and potassium violet. Different atoms will release different wavelengths of light when they're electrons are excited and induced to jump to higher energy levels and fall back, in this case as a result of heat.

[kortvez]

There is a mix' date=' which gives a relatively cold fire.

 

A mix of carbon disulfide and carbon tetrachloride (appr. 1:1 by volume) burns with a fairly cool flame.

 

In the past, magicians sometimes used this mix. They spilt it on their skin and lit the mix. The flames did not burn them, although they still feel quite hot. But with some motion the heat is bearable.

[/quote']

 

 

You can also try burning alcohol (>50% or 100 proof). It's actually a very nice experiment if you soak a piece of paper with this alcohol and lit it. If you let it to burn for only a short time, you won't see any burns on the paper.

[RyanJ]

You can also try burning alcohol (>50% or 100 proof). It's actually a very nice experiment if you soak a piece of paper with this alcohol and lit it. If you let it to burn for only a short time, you won't see any burns on the paper.

 

DO Not Do This!

 

I have actually seen people do this un their hands though the problem comes when the alcohol starts to run out

 

More informaiton on flame colours can be found here

 

Cheers,

 

Ryan Jones

[jdurg]

Just a note of caution here; be VERY careful with alcohol fires. I've seen too many people get hurt because of accidents involving alcohols and flame. Alcohols that people typically encounter are VERY flammable materials which evaporate very readily. As a result, a flammable field of vapor will quickly form over a puddle of alcohol. In addition, because of the chemical composition of alcohols their flame is virtually invisible. If you don't watch it the entire time, you may forget where the flame is and accidentally burn yourself or others. The most sickening site I ever saw was an automobile accident where a methanol tanker ruptured and caught fire. The fire-fighters were not aware that it was a methanol fire and started walking towards the tanker to see if people were trapped near it. The people walking towards, and away, from the fire suddenly erupted in flame when they were near the tanker. The CH3OH was burning perfectly clear and people were walking right into the flame because they couldn't see it. A thermal filter was then put on the camera filming it and you could then see the fire. Still, a lot of people suffered VERY nasty burns simply because they couldn't see the fire.

 

So when working with alcohols and fire, be INCREDIBLY carefull. One moment of carelessness could result in some nasty burns.