How is carbon monoxide produced during fuel combustion?

Carbon monoxide is produced during fuel combustion primarily through incomplete combustion. This occurs when there is not enough oxygen available for the fuel to react completely. In a situation of incomplete combustion, the fuel does not fully convert into carbon dioxide and water, resulting in the production of carbon monoxide as a byproduct.

In complete combustion, where there is sufficient oxygen, hydrocarbons are fully oxidized to produce carbon dioxide and water, thus preventing the formation of harmful products like carbon monoxide. The process of combustion typically involves breaking down chemical bonds in the fuel, and when oxygen levels are limited, some of the carbon atoms are left unreacted, leading to the generation of carbon monoxide, a toxic gas.