A material that burns combines quickly with oxygen in the air. Burning, then, is a rapid process of oxidation. Most materials that burn are made up of mainly carbon and hydrogen. Combustion is another name for burning.
In 17th century combustion was explained by other theory. Antoine Lavoisier, a French Chemist, discovered in 1774, that oxygen is essential for combustion. Some substances combine with oxygen extremely slowly. In that case no light and very little heat is produced. Rusting of iron is an example of such a slow oxidation.
For a fuel to burn, certain conditions must be met. First, a substance that can burn must be present. Second, a good supply of oxygen must be present. Third, the fuel must be treated until it reaches its ignition temperature. The ignition temperature is also called the kindling point.
Some substances like paper have low kindling points while other fuels like coal must be heated considerably before they can burn. Some substances like white phosphorus have a very low ignition point that is why it is kept under water.
It would be almost impossible to count the number of ways in which fire is used. Fire provides light and cooks the food. Fire is used to heat water to make steam. Steam is used to run umpteen kinds of engines. Fire is used in industries for separating metals from their ores. Fire is also used in automobiles, boats and airplanes.
When fire is under control it might be called man’s best friend. But once it gets out of control it is undoubtedly his worst enemy. Every year fires kill thousands of lives. It can destroy buildings and forests in large a proportion if it gets out of control.
