Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 exam•Written by the Fiveable Content Team • Last updated September 2025
Definition
Nitrogen dioxide is a reddish-brown gas that forms when nitrogen oxide reacts with oxygen in the atmosphere. It is mainly produced by vehicle emissions and industrial processes, contributing to air pollution.
Nitrogen dioxide plays a significant role in forming smog, which is a type of air pollution characterized by hazy conditions caused by pollutants like nitrogen oxides.
Ozone Layer Depletion: Nitrogen oxides contribute to ozone layer depletion when they react with other chemicals high up in the atmosphere, leading to environmental concerns.
Combustion Engines: Vehicles powered by combustion engines produce nitrogen oxide emissions during fuel combustion. Understanding combustion engines helps us understand the main source of nitrogen dioxide.