Gases:
* Carbon Dioxide (CO2): The main product of combustion, it's a greenhouse gas.
* Water Vapor (H2O): Formed from the hydrogen in the fuel combining with oxygen.
* Nitrogen (N2): A major component of air, it passes through the engine largely unchanged.
* Carbon Monoxide (CO): A toxic gas produced when there isn't enough oxygen for complete combustion.
* Nitrogen Oxides (NOx): Formed at high temperatures, they contribute to smog and acid rain.
* Unburnt Hydrocarbons (HC): These are unburned fuel molecules that contribute to smog.
* Sulfur Dioxide (SO2): Produced from the sulfur impurities in gasoline, contributing to acid rain.
Particulate Matter:
* Soot: Tiny particles of carbon that can be inhaled and cause respiratory problems.
* Ash: Inorganic particles that can be harmful to health.
The exact composition of these products varies depending on:
* Engine type and condition: Older engines produce more pollutants.
* Fuel quality: The amount of sulfur and other impurities in the fuel affects the emissions.
* Air-fuel ratio: The amount of air mixed with the fuel determines how efficiently the fuel burns.
Note: Modern vehicles have catalytic converters that help reduce the harmful emissions like CO, NOx, and HC. However, complete elimination of pollutants is impossible.
