John Emsley, The Elements, 3rd ed. Oxford, Clarendon Press, , p. David L. Heiserman, Exploring Chemical Elements and their Compounds. Navigation Bar. Folks who are addicted to tobacco, are the very folks who have to use oxygen to assist with their breathing.
Their cigarette does not explode, nor ignite, and neither does the oxygen around the burning cigarette and supply tank. That is how oxygen supports combustion. It does not burn up the cigarette as you may imagine. It only makes the cigarette burn hotter. Think of oxygen as a fertilizer for fire.
So what is this about oxygen being flammable? Also read: Is Water Flammable? Should You Be Worried? It is well known that in order for fire to occur, it takes three elements called the fire triangle.
Firefighters know that in order to stifle put out a fire, you must remove one or more of the three elements. If you were to smother the fire, hence removing the oxygen, it would eventually burn out.
But if you remove the blanket too soon, the remaining heat would find more oxygen and reignite. The presence of oxygen in an area that is sufficiently heated, will cause a fire to become supported by the oxygen, but it is not burning; otherwise, we would call it fuel.
To complicate matters slightly, firefighters and scientists add a fourth dimension to the fire triangle, called the fire tetrahedron. A tetrahedron is a four-sided triangle which in this case adds a fourth element to the fire triangle.
Free radicals are combinations of many flammable elements which also exacerbate the combustion process. Among other techniques, they can be eliminated by a layer of dry chemical agents.
The removal of free radicals can easily be accomplished in smaller fires. The production of smoke and its various elements call for large quantities of water, and effective application. Oxygen gases and other components of combustion make fire more difficult to extinguish in these large fires, but once the job is done, respiratory issues cease to be a factor. It should be noted that, as long as a fire is still smoldering and is emitting products of combustion, you can still be breathing lots of poisonous gases, free radicals and breathing apparatus SCBA must still be worn.
Also read: Is Carbon Dioxide Flammable? Yes and No…. Liquid oxygen is simply regular oxygen that is compressed from a gas into a liquid. The danger we often hear about with high oxygen levels is that other materials that are not combustible or only very slightly combustible under normal conditions, and therefore not a danger, can become very combustible and hazardous when oxygen levels are high.
Also, many things will be hot or will smolder when deprived of air and thus oxygen , and will suddenly burst into flame when exposed to the oxygen that's in our air.
Examples of this include oily rags in a trash can that ignite when someone lifts off the can's lid, or toast in a toaster oven that is black and smoky and that bursts into flame when someone opens the oven door. Since oxygen is required for the burning we see , the sudden combustion in these examples would be more dangerous if the oxygen concentration were higher. One final thing to note is the difference between combustion and spontaneous combustion.
All burning is combustion, but it's only spontaneous combustion if the burning results from a heat-producing reaction instead of from a spark or some other ignition. So the toast example is of combustion, but the oily rags example is spontaneous combustion. If you have a material that's not combustible in normal conditions but is extremely combustible in high-oxygen conditions, that doesn't necessarily mean that it will automatically explode when exposed to the oxygen.
It varies depending on what substance we're talking about, but it might still take a little spark or some other trigger to get it to combust.
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