How is it that oxygen, which supports fire, helps in extinguishing fire when combined with hydrogen…?
467356
It's a completely different chemical once combined with Hydrogen in the form of water.  It's going to have a completely different set of properties.
674853
Exhaled air is only about 3% carbon dioxide and is still around 18% oxgyen.  This is not the reason.  If it were, blowing air with a fan or high wind would not blow it out.\nIt blows it out because you are separating the heat from the fuel source.  The bigger the fire, the harder you need to blow.  If they are separated and the fuel source is not hot enough to re-ignite, it blows out.
919229
FIRE is rapid oxidation.  It is a chemical reaction between oxygen  and other materials (solid or liquid).  The flame you see is the point at which the material is converted into a gas.  This point is called the sublime.\n  To maintain sublimation (flame) you must have a constant supply of materials (solid or liquid) and a constant supply of oxygen.  \n  Fire is made by raising the temperature of a material (solid or liquid) to its point of sublimation in an oxygen filled enviornment.\n  FYI,  RUST is slow oxidation
570305
yes! liquid oxygen and liquid hydrogen.  mix them together, light a match and stand back.
6674
Because, it was smoking before but the fire *combustion* was using all the smoke to sustain the fire.   When the fire was put out, the material was still producing flamable gasses but they were just going into the atmosphere insted of burning. \n\nyeah and eat that bad sentance structure grammar crazy person above me!
1181278
When atoms (elements) are chemically combined to form molecules the combination makes an new substance with characteristics very different than each separate element.  Water extinguishes fire because it reduces heat and oxygen.  The fire does not break up the water molecules to form free hydrogen and oxygen.
1158356
By itself, water is an unreactive substance by nature. So you cannot separate oxygen and hydrogen from the water molecules. However, there is only one ay in hich this canbe done: electrolysis.\n\nIt involves the passage of an electric current into a liquid, which naturally conducts electricity. Electrodes are used to pass the electric current. At both the electrodes, gases are evolved, depending upon the liquid.\n\nSome acid or alkali should be added to water for the evolution of gases, namely hydogen and oxygen at the electrodes.\n\n\n\nIt can be mass-produced, but the process is too costly. An application could be to use hydrogen in hydrogen powered cars to replace the more polluting petrol powered cars. \n\nMoreover, oxygen is also obtained by the fractional distillation of liquid air. It involves cooling air by decreasing the its pressure by placing them in special containers, capable of bearing atmospheric pressure. This process is more economical, compared to electrolysis. Liquid oxygen and hydrogen is used to power rockets in order to propel them into space. This process for the production of liquid oxygen and hydrogen is mass produced nowadays to power rocket and hydrogen powered cars. \n\nThanks
332898
Carbon dioxide (CO2) is effective as an extinguishing agent primarily because it reduces the oxygen content of air to a point where combustion cannot continue. CO2 is non combustible and does not react with most substances. Being a gas it can penetrate and spread to all areas affected by fire. Carbon dioxide fire extinguishers are used for putting out fires in oils, petroleum products, gaseous substances under pressure, and also on sophisticated electrical and electronic apparatus.\n\nCarbon dioxide extinguishers are not to be used in \n\ni) Fires involving chemicals that contain their own oxygen supply (such as cellulose nitrate). \n\nii) Fires invotving reactive metals such as sodium, potassium and magnesium. \n\nHow Does Carbon Dioxide Extinguish Fire\nWhen the extinguisher is actuated carbon dioxide from the cylinder comes out at a considerable velocity into the atmosphere and forms a layer of gas which is about one and half times heavier than air. The vapour blanket puts out fire by displacing the air around the fire and reducing the oxygen supply needed to continue combustion.\n\nI hope that info helps. For any further information please check this link:\n\nhttp://www.fireturnkey.com/ext_types.htm
987162
The sun isn't burning. Fire is a chemical process, and it almost always involves oxygen (air), which isn't really common in space. Instead, the sun is exploding from nuclear fusion. All the fuel floats around the sun in an extremely hot plasma, kept near the core by gravity like our own air is kept near the earth. In the middle of the sun, all the plasma on top is pressing down so hard that hydrogen atoms fuse together into helium (and rarely some other stuff), causing a huge explosion and pushing everything back up and out, only to be drawn back in by their weight to do it again. Not all the hydrogen has been fused together yet (there's a heck of a lot of it there) but when it does the sun will collapse, but eventually it will squeeze everything so hard that even the helium will begin fusing together. I don't remember what happens after that, but eventually when the helium runs out the sun will collapse again, either becoming a much smaller white star that fuses something harder and heavier than hydrogen and helium or goes nova, exploding with a sudden combination all at once before gravity can pull it back together again. The sun's too small to become a black hole though, probably. We can estimate how hot the sun is on it's surface by seeing how hot it is way out here on earth, just like you can estimate that a fire in your fireplace is hot by holding your hand near it without having to actually touch it, and by using mathematical models of nuclear reactions.
248810
It's a matter of thermodynamics.  The end product of burning hydrogen with oxygen in an engine, or recombining it in a fuel cell, is water.  So, if you're going from water to hydrogen and oxygen, and then back to water when you burn it, the heat given off by the chemical reaction you're using to power the engine is the same as the amount of energy it took to split the hydrogen from the water in the first place.  Add to this the limitations of efficiency on engines, or any other device, and it ends up being impossible to have an engine that runs on water.  If you have some other power source, you can use this to split the hydrogen, and then burn it in your engine, but then the energy really isn't coming from the water being used as a fuel, you're just using the hydrogen to carry the energy from your power source to your engine.  \n\nNow, if you had a pure fluorine atmosphere, you could burn water in an engine, but I'm not sure what you could make an engine out of such that it wouldn't be destroyed by the fluorine!
641178
"Fire is the rapid combination of oxygen with fuel in the presence of heat, typically characterized by flame, a body of incandescent gas that contains and sustains the reaction and emits light and heat." \n\nLet's go through this bit by bit:\n\n(1) Rapid combination of oxygen with fuel in the presence of heat. Oxygen, fuel, and heat are the essential ingredients of fire.\n\n(2) Typically characterized by flame. The pup qualifier "typically" allows me to sidestep the issue of apparently nonflaming fires, like you get with burning charcoal. I suspect charcoal fires do create flame--you just can't see it due to the lack of impurities or incompletely burned fuel in the plume. (You can't see a fuel fire at an Indy or CART race either, because the cars run on clean-burning methanol.) But that's a matter we can leave for another day.\n\n(3) Body of incandescent gas. Flame defined. Most encyclopedia and dictionary definitions blow past this entirely, allowing persons such as yourself to imagine that fire is "pure energy" or similar nonsense. We say "body" because the gas has a characteristic structure and composition. We say "incandescent" because (a) it sounds scientific, (b) it means "luminous with intense heat," precisely what we are attempting to convey, and (c) if the Teeming Millions are going to learn one vocabulary word today, by God "incandescent" should be it.\n\n(4) Contains and sustains the reaction. Flame isn't just the result of fire; it is the fire. What's more, without the flame's heat the fire would go out.\n\n(5) Emits light and heat. Duh. However, we mustn't overlook the obvious.
134371
Although some have talked about this, there are a lot of technical and practical questions to answer before this can happen. For example:\n\nWhat energy are you going to use to separate water into oxygen and hydrogen? \n\nHow are you going to store the hydrogen safely and dispense it? \n\nHow are you going to transport the hydrogeon?\n\nWill you keep the hydrogen liquid so it will not take up much room? \n\nHow will you keep the hydrogen liquid from warming up ? \n\nHow will you prevent terrible fires and explosions from accidents?\n\nWill you produce less pollution by using hydrogen, or more, given that you are having to use energy to create it? \n\nHow will you make the transition from petrochemical fuels to hydrogen fuels?\n\nWho is going to pay for this transition?\n\nHow are you going to build the very expensive infrastructure?\n\nProbably lots more questions too. Those are enough to start with, however.
361585
Put the lighted end of a glowing splinter into a test tube containing the subject gas. If it burns or bursts into flames, you have oxygen in there. But if the splinter makes a pop, you have hydrogen instead. If it is extinguished, you got carbon dioxide
111874
Once something has already burned, it will not burn again. Water is the result of hydrogen burning.
1020809
Oxygen is only the supporter of combustion.\nYou said that a burning matchstick when brought close to oxygen burns brightly only.\nThe matchstick is burning due to red phosphorus only.when its brought nearer to oxygen its burning brightly.\nThe gas needs LP(liquified petroleum) to burn.We need not to add oxygen because oxygen is present in large quantities.
903700
That is definitely not correct!!\n\nFor example water (H20) is very very different from the two gases that make it namely hydrogen (H2) and oxygen (O2)
302677
Hydrogen is the lightest and flamable, in other word, can be burned, element in its natural form, which is gas. Once it 's been turned into liquid itself, hydrogen does not hold its characteristics well because of the temperature is being used to keep the liquid form. So hydrogen, itself, already not stable.\nOxygen, on the other side, have most its characteristics in liquid or gas form. It is not flamable in the sense that it can not cause fire. But it can be burned and is needed for the existence of fire. So Oxygen is a little more stable.\nNow once Oxygen and Hydrogen combine together, because Hydrogen is very light, and Oxygen is heavier (it really involves all the atoms, especially electrons), Hydrogen tends to assume some characteristics of Oxygen. This includes the stable condition.\nAlthough after combined, they show to be very stable and hold very tight to each other, there was a explosion during the process of combining. As we know, water is the molecular compound, H2O, which means two molecules of hydrogen and a molecule of Oxygen in the mixture. In the normal process of making true water, an estimated amount of Hydrogen and Oxygen gases are put into tank with the ratio of 2:1. However, it is only estimated, so sometimes one gas can be a little more than the other. Also, they are both put in tank in very small amount at the time, then add some more. So the reaction would be slow and controllable.\nIf the two gases are put in at the same time, exact Hydrogen and Oxygen at the ratio of 2:1, and large amounts, they can become Water Bomb. Thus, water does reach a flash point (just not when heated).\nYour question is not stupid. It is very interesting and very smart. Normal people would not care to think out of the box or would not know more than they should. You should reward yourself for being brave enough to ask. But this is the important thing: I recommend you not to try the Water Bomb because it requires very detail and exact conditions. It should only be done in lab with supervisor. The explosion can be big...