Combustion: what it is, types and examples

The combustion process can develop in different ways, depending on the materials involved in it and the products that are produced. Therefore, there are the following types of combustion:

• Complete combustion . It is the oxidation of a hydrocarbon that produces only carbon dioxide and water. This type of combustion occurs when lighting a candle: the heat from the burning wick turns the candle wax , which is a hydrocarbon, into a vapor . The wax, in turn, reacts with oxygen and releases carbon dioxide and water. The candle is completely consumed and the products dissipate into the air.
• incomplete combustion . It produces traces of carbon (soot) and carbon monoxide, as well as water and carbon dioxide. Most fossil fuels, such as coal, undergo incomplete combustion.
• stoichiometric combustion . It is also called neutral combustion and it is a chemical process that is carried out with ideal proportions of oxygen and combustible materials. Generally, this type of combustion is carried out in laboratories.

Also, combustion reactions can be:

• Slow combustion , which produces little emission of light and heat. An example may be a fire that occurs in a poorly ventilated room. It is a dangerous situation because if more oxygen enters , the fire can suddenly increase.
• Rapid combustion , which is characterized by a great emission of light and heat. If it’s too fast, it can cause an explosion. Explosions are considered as flash fires.

Combustion Examples

In nature and everyday life there are numerous examples of combustion. Some of the most common are:

• Strike a match. The match head has phosphorus and sulfur. When scratched, it heats up and causes rapid combustion. Something similar occurs with the butane combustion reaction, present in lighters whose adjusted chemical equation is: 2C ₄ H ₁₀ (g) +13O ₂ (g) → 8CO ₂ (g) +10H ₂ O(g).
• Forest fires. They occur in many cases due to droughts or electrical storms. The heat from an electrical discharge and even elevated temperatures can cause trees or grass to burn.
• Turn on a gas stove. With the pilot flame or by means of a match, the gaseous hydrocarbon, which is usually butane (C ₄ H ₁₀ ) or propane (C ₃ H ₈ ), comes into contact with oxygen and causes combustion. The balanced chemical equation of the propane combustion reaction is expressed as follows: 2C ₃ H ₈ (g) + 7O ₂ (g) → 6CO ₂ (g) + 8H ₂ O(g).
• Cook on the grill. When coal, which is a fossil fuel, is ignited, it reacts with oxygen and releases energy in the form of heat, which is used to grill meat or other foods.
• Start a car. It is another example of the use of fossil fuels, such as gasoline. The burning of this hydrocarbon causes controlled explosions that produce energy (which is why car engines are called “explosion”). This generates the movement and release of other gases.

Bibliography

• García Bello, D. Everything is a matter of chemistry . (2016). Spain. Paidos Iberica.
• Nguyen-Kim, MT My life is chemistry . (2020). Spain. Editorial Ariel.
• Masterton, WL; Hurley, C.N. Chemistry: Principles and Reactions . (2003, 4th edition). Spain. B&W.