What Is Fire?
‘Combustion’ is the scientific name given to burning. These are of different types. Oxygen from the air combines with another material that can burn.
This reaction produces heat. In case the process is rapid, we see flames or an intense glow and actually feels combustion as in an explosion. In automobiles too, we have combustion. The oxygen from air combines with gasoline to burn.
The combustion in automobiles is so rapid that we call it an explosion. At the other end, we have a kind of combustion, going on slowly, unnoticed for a year. Rusting of iron is a slow process of burning.
In case of slow combustion, the resulting heat cannot escape into the air and temperature may rise to assume active burning. This is named “spontaneous combustion”. It may occur in a heap of oil rags left in a closed place. The oil gets oxidized or burning which results in heat. There is no escape from heat and keeps accumulating and eventually, there will be enough heat to cause the cloth to burst into flames. Oxygen is most common in nature and is most essential to cause combustion. The oxygen content in the air is 21% and is always ready to enter into combustion.
The ‘combustible’ materials are as necessary as oxygen to cause combustion. These materials are classified as “inflammable” and are planned for use for combustion. These materials are called fuels. The common examples are wood, coal, coke, fuel oil, kerosene, and certain gases.
One atom of carbon combines with two atoms of oxygen from the air and forms a molecule of a new substance called “carbon dioxide”. The combustion process goes into our body to generate heat and energy and creates carbon dioxide that we breathe out.