Which gas is the end product of complete combustion?

Complete combustion occurs when a fuel reacts fully with oxygen, producing energy along with specific end products. In the case of hydrocarbons, which are commonly used fuels, the primary end product of complete combustion is carbon dioxide.

During complete combustion, the carbon in the fuel combines with oxygen from the air to form carbon dioxide, while hydrogen combines with oxygen to form water vapor. This process maximizes the efficiency of fuel use, releasing the most energy and minimizing the production of harmful byproducts.

The other gases mentioned—nitrogen dioxide, sulfur dioxide, and carbon monoxide—are typically associated with incomplete combustion or specific conditions involving additional elements or impurities. For example, nitrogen dioxide forms in combustion processes that are not ideally controlled, sulfur dioxide results from burning sulfur-containing fuels, and carbon monoxide is produced when there is insufficient oxygen for complete combustion.

Thus, carbon dioxide's role as the primary end product of complete combustion accurately reflects the chemical processes involved in burning fuels in the presence of adequate oxygen.