nitrogen oxide

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Two pie charts compare sources of sulfur dioxide and nitrogen oxides emissions contributing to acid rain. The first chart shows electric utilities produce 66% of SO2, other sources 29%, and vehicles 5%. The second chart shows vehicles produce 58% of NOx, other sources 24%, and electric utilities 18%.

nitrogen oxide

chemical compound

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Two pie charts compare sources of sulfur dioxide and nitrogen oxides emissions contributing to acid rain. The first chart shows electric utilities produce 66% of SO2, other sources 29%, and vehicles 5%. The second chart shows vehicles produce 58% of NOx, other sources 24%, and electric utilities 18%. — SO₂ and NO_x emissions in the U.S. SO₂ and NO_x emissions in the U.S., 2008.

Nitrogen oxides are chemical compounds formed when nitrogen reacts with oxygen, often during combustion processes. These compounds are considered atmospheric pollutants.1

Key nitrogen oxides include:
* Nitric oxide (NO): Formed by lightning or heating nitrogen and oxygen. It's also a pollutant from internal-combustion engines.2
* Nitrogen dioxide (NO₂): A pungent, irritating gas that contributes to acid rain and photochemical smog. It is formed when combustion temperatures are high enough to cause nitrogen in the air to react with oxygen.3
* Nitrous oxide (N₂O): Also known as laughing gas, it's used as an anesthetic and propellant.2

Nitrogen oxides are among the six major air pollutants designated as "criteria pollutants" due to their impact on air quality.3

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oxide
Oxides of nitrogen
…2HNO₃ + NO Nitrogen (N) forms oxides in which nitrogen exhibits each of its positive oxidation numbers from +1 to +5.
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…2HNO₃ + NO Nitrogen (N) forms oxides in which nitrogen exhibits each of its positive oxidation numbers from +1 to +5.
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environmental economics
Examples of regulation using corrective instruments
…million tons, a reduction in nitrogen oxide emissions (as compared with 1990 levels) of more than three million tons, and nearly 100 percent program compliance.
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…million tons, a reduction in nitrogen oxide emissions (as compared with 1990 levels) of more than three million tons, and nearly 100 percent program compliance.
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nitrogen
Compounds
Many of the nitrogen oxides are extremely volatile; they are prime sources of pollution in the atmosphere. Nitrous oxide, also known as laughing gas, is sometimes used as an anesthetic; when inhaled it produces mild hysteria. Nitric oxide reacts rapidly with oxygen to form brown nitrogen dioxide, an…
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Many of the nitrogen oxides are extremely volatile; they are prime sources of pollution in the atmosphere. Nitrous oxide, also known as laughing gas, is sometimes used as an anesthetic; when inhaled it produces mild hysteria. Nitric oxide reacts rapidly with oxygen to form brown nitrogen dioxide, an…
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respiratory disease
Air pollution
…begins with the emission of nitrogen oxide during the morning commuting hour, followed by the formation of nitrogen dioxide by oxygenation, and finally, through a complex series of reactions in the presence of hydrocarbons and sunlight, leads to the formation of ozone and peroxyacetyl nitrite and other irritant compounds. Eye…
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…begins with the emission of nitrogen oxide during the morning commuting hour, followed by the formation of nitrogen dioxide by oxygenation, and finally, through a complex series of reactions in the presence of hydrocarbons and sunlight, leads to the formation of ozone and peroxyacetyl nitrite and other irritant compounds. Eye…
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poison
General air pollutants
Both ozone and nitrogen oxides are oxidizing pollutants. Like sulfur dioxide, they cause respiratory irritation; ozone and nitrogen oxides, however, tend to be more irritating to the lung than to the upper respiratory tract.
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Both ozone and nitrogen oxides are oxidizing pollutants. Like sulfur dioxide, they cause respiratory irritation; ozone and nitrogen oxides, however, tend to be more irritating to the lung than to the upper respiratory tract.
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