Question

How do the oxides of nitrogen enter the atmosphere?

Answer 1

• Oxides of nitrogen, nitric oxide (NO) and nitrogen dioxide (NO₂), enter the atmosphere in the following ways:
• On the burning of fuels in furnaces, the temperature increases. At high temperatures, nitrogen and oxygen present in the air combine to form oxides of nitrogen.
• Oxides of nitrogen are produced during the burning of fuel in an internal combustion engine. They enter the atmosphere as exhaust gases.
• During thunderstorms, nitric oxide is formed by the reaction between atmospheric nitrogen and oxygen in the presence of electric discharge.
• Nitric oxide further reacts with atmospheric oxygen and ozone to form nitrogen dioxide.