Which of the following gases is primarily removed by catalytic converters?

Catalytic converters are essential components in the exhaust systems of vehicles, designed to reduce harmful emissions. One of the primary gases that catalytic converters target is nitric oxide, which is a nitrogen oxide (NOx) compound. Nitric oxide is produced during combustion at high temperatures and contributes to the formation of smog and acid rain, posing risks to both health and the environment.

The catalytic converter facilitates a chemical reaction that converts harmful gases, including nitric oxide, into less harmful substances before they are released into the atmosphere. Specifically, through reduction reactions, nitric oxide is typically transformed into nitrogen and oxygen, which are harmless components of the air we breathe.

In contrast, the other gases listed—oxygen, nitrogen, and carbon dioxide—are not the main focus of catalytic converters. Oxygen is necessary for combustion but is not considered a pollutant, while nitrogen makes up a significant portion of our atmosphere and does not contribute to vehicle emissions. Carbon dioxide, though a greenhouse gas, is not specifically targeted for removal by catalytic converters; instead, its production is more a matter of fuel efficiency and complete combustion rather than a direct reduction through a catalytic process.

Therefore, the primary function of catalytic converters is to minimize the emission of nitrogen oxides, particularly nitric oxide, making