Fire
 |
This article does not have any sources. You can help Wikipedia by finding sources, and adding them. Tagged since April 2009 |
Fire is a chemical reaction that gives off light and heat. It is one of the most familiar examples of the chemical process of oxidation.[source?]
Contents |
[change] Safety
Fire is very hot. It should never be touched, for it may burn anything that gets too close. If touched with human skin, the skin may blister which can take some time to heal. If a fire occurs you should cover your mouth with a cold cloth because if you breathe in too much smoke you can faint.
[change] Uses
Fire can be very useful if it is treated carefully. It has always been very important for people to be able to make fire, because people need its heat on cold days, or its light in darkness, or its heat for cooking.
[change] Destructive Uses
If fire is not treated carefully, it can be very dangerous. A fire that got out of control once destroyed 17,400 km²,an area the size of New York City, in the United States[source?]. Forests can burn down if fires are not controlled. Every year, large areas of forests are destroyed because of fire, particularly in Europe. This usually happens in summer. Firefighters are people with special training to stop fires, or to keep a fire under control.
Fire needs three things to burn: oxygen, fuel, and heat. Fuels can be wood, tinder, coal, or any other substance that will easily oxidize. Once a fire is burning, it creates its own heat, which allows the fire to keep burning on its own for some time.
[change] Controlling
A fire can be stopped in three different ways, by removing any of the three things it needs to burn:
- The fuel can be removed. If a fire burns through all of its fuel and extra nearby fuel is removed, the fire will stop burning.
- The oxygen can be removed. This is called "smothering" a fire. Fires cannot burn in a vacuum or if they are covered in carbon dioxide.
- The heat can be removed. The most common way to remove heat is to use water to absorb that heat, putting the fire out.
However, some fires cannot be smothered, such as magnesium flames. They can burn in CO2, nitrogen, and some other elemental compounds.
[change] Reactions
Fires are usually combustion reactions that take carbon, hydrogen, and oxygen.[source?] The products are very commonly water, and carbon dioxide, although there are other examples that avoid this generalization, such as burning magnesium in air, which makes magnesium oxide. Fires can occur in many ways and there are many types of fire which, if not treated correctly, can cause total devastation. There are wood fires, gas fires, metal fires, and more.
Wood fires can usually be put out with water used to absorb the heat, but metal fires are too hot for water to absorb enough heat to put out the fire. If water is used to extinguish ("put out") a metal fire, the water will simply evaporate. For metal fires, sand can be used to cover the fire and choke it off from obtaining oxygen. A fire extinguisher can put out most fires.
