The chemistry of combustion is a process where a fuel reacts with oxygen in the presence of heat, resulting in the release of energy in the form of light and heat. The process can be explained using the fire triangle, which represents the three essential components required for combustion to occur: fuel, oxygen, and heat.

For example, in the case of hydrocarbons like gasoline or methane (natural gas), the combustion reaction can be represented as follows:

Fuel (hydrocarbon) + Oxygen → Carbon dioxide + Water + Energy

C8H18 (Octane) + 12.5O2 → 8CO2 + 9H2O + Energy

During combustion, the oxygen reacts with the carbon, hydrogen, and other elements present in the fuel, breaking the chemical bonds and forming new compounds like carbon dioxide and water.

Once the combustion reaction begins, the energy released during the process further provides the heat needed to sustain the reaction. The heat generated helps maintain the high temperature required to continue the combustion process.

The Fire Triangle: The fire triangle represents the interdependence of these three components in the process of combustion. If any side of the triangle is removed, combustion cannot occur. For example:

• If the fuel is removed or depleted, there is nothing to burn, and the fire will be extinguished.
• If oxygen is restricted or removed (e.g., in a sealed container), the fire will be deprived of the oxidizing agent necessary for combustion, causing it to go out.
• If heat is removed (e.g., by cooling the fuel or using a fire extinguisher), the combustion reaction cannot sustain the high temperature required for continued burning, and the fire will be extinguished.

The fire triangle helps to understand the essential components needed for combustion and is a fundamental concept in fire safety and firefighting.