Human beings have always been fascinated by using the fire. But it is during the last decades we have actually started to understand the science behind it. This is due to the reason for this breakthrough is the use of modern scientific tools. Such tools are developed and utilized in the scientific work at our division. Combustion is a chemical process involving hydrocarbon and oxygen. In the process of the combustion, fuel is oxidized and large amounts of chemically bound energy are released. In this article, we will learn the concept of combustion and combustion formula with examples. Let us begin learning!
Concept of Combustion
Combustion is a chemical process or a reaction between Fuel i.e. Hydrocarbons and Oxygen. When fuel and oxygen react it releases the energy in form of heat and light. Heat and light energy then result in a flame. The combustion process is used in car motors and rocket engines and in many other types of machinery. Mainly combustions are of 5 different types.
Examples of Combustion
- Burning of Wood and Coal at our home
- Burning of Petrol and Diesel in our vehicles
- Combustion of CNG, PNG or LPG to cook for on your stovetop
- For the production of energy in thermal power plants
Thus, combustion encompasses a great variety of phenomena with wide application in the industry as well as in science. It also happens in our home also. And its applications are based on the knowledge of physics, chemistry, and mechanics. Their interrelationship becomes particularly evident in treating flame propagation.
This energy heats the products. Combustion of a fuel such as methane with air leads to a flame temperature of around 1900 ºC. In the combustion of methane with air. Its main products are carbon dioxide and water. But, the formation of these products is very complex. This is because of hundreds of different species like H, O, OH, CH, CH3, etc. are intermediates in the combustion process.
Besides carbon dioxide and water, a large number of pollutants are also produced, for instance, nitrogen oxides, carbon monoxide, and soot particles. The efficiency and cleanliness of the combustion process depending on several parameters. Some parameters are oxygen supply, temperature history, and mixing properties.
Therefore we may conclude that it is a rapid chemical reaction of a substance with oxygen and with the production of heat and light. Also, it is an exothermic reaction accompanied by the development of heat due to which temperature rises considerably.
The heat produced during combustion = Heat of formation of the products – Heat of the formation of reactants.
The complete Combustion process is oxidation of hydrocarbon producing only \(CO_2 and H_2O\). For example clean combustion of the burning of the candle wax.
Incomplete Combustion is hydrocarbon oxidation that produces carbon monoxide i.e. CO in addition to \(CO_2\). For example burning coal, where a lot of soot and carbon monoxide is released.
Q.1 Write down the Combustion formula for Methane.
Solution: \(CH_4 + 2 O_2 → CO_2 + 2 H_2O\) + Energy
Q.2: Write down the combustion formula for Ethane:
Solution: \(2 C_2H_6 + 7 O_2 → 4 CO_2 + 6 H_2O + Energy\)