Soot and smoke are the results of what type of combustion?

The presence of soot and smoke indicates an incomplete combustion process. Incomplete combustion occurs when there is not enough oxygen available for the fuel to burn entirely. This insufficient oxygen supply leads to the formation of solid particles, such as soot, and unburned fuel, which can become visible as smoke.

Complete combustion, on the other hand, involves a sufficient supply of oxygen, resulting in the fuel burning efficiently and producing carbon dioxide and water as byproducts, without the production of soot or smoke. The terms "optimal combustion" and "boiler combustion" are not standard classifications in combustion science and do not specifically address the presence of soot and smoke. Therefore, the identification of incomplete combustion as the cause of soot and smoke is accurate, highlighting the importance of proper air supply and combustion efficiency in fuel-burning processes.