Do nitrous oxides constitute approximately 50% of the pollutants in automobile exhaust?

Nitrous oxides (NOx) are not comprised of approximately 50% of the pollutants found in automobile exhaust. Instead, the primary pollutants in vehicle emissions include carbon monoxide, carbon dioxide, hydrocarbons, and particulate matter, with nitrous oxides accounting for a smaller percentage of these emissions.

NOx gases, which include nitrogen monoxide (NO) and nitrogen dioxide (NO2), mainly result from high-temperature combustion processes, but their contribution to overall automobile exhaust is significantly less than half. Rather, NOx levels are critically monitored due to their role in forming smog and impacting air quality, rather than making up the majority of air pollutants. This understanding of emission composition is vital for addressing environmental impacts and implementing regulatory measures.