What is the result of incomplete fuel combustion?

Incomplete fuel combustion primarily produces carbon monoxide. When a fuel burns completely in the presence of sufficient oxygen, it produces carbon dioxide, water, and energy. However, if there is an insufficient supply of oxygen, the combustion process is incomplete, leading to the formation of carbon monoxide instead of carbon dioxide.

Carbon monoxide is a colorless, odorless gas that can be particularly harmful to human health, as it interferes with the blood’s ability to carry oxygen. This process typically occurs in environments with limited ventilation or with fuel-burning appliances that aren't working correctly.

In contrast, sulfur dioxide and nitric oxide are primarily produced from other processes, such as the combustion of fossil fuels containing sulfur and the oxidation of nitrogen during high-temperature combustion, respectively. These gases result from different chemical reactions and are not indicative of incomplete combustion.