WordNet

a common nonmetallic element that is normally a colorless odorless tasteless inert diatomic gas; constitutes 78 percent of the atmosphere by volume; a constituent of all living tissues (同)N, atomic number 7
an oxide containing two atoms of oxygen in the molecule

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『窒素』(気体元素;化学記号は『N』)
二酸化物

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2017/05/16 09:33:54」(JST)

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Nitrogen dioxide is the chemical compound with the formula NO
2. It is one of several nitrogen oxides. NO
2 is an intermediate in the industrial synthesis of nitric acid, millions of tons of which are produced each year. At higher temperatures it is a reddish-brown gas that has a characteristic sharp, biting odor and is a prominent air pollutant.^[7] Nitrogen dioxide is a paramagnetic, bent molecule with C_2v point group symmetry.

1 Properties
2 Preparation and reactions
- 2.1 Main reactions
  - 2.1.1 Basic thermal properties
  - 2.1.2 As an oxidizer
  - 2.1.3 Hydrolysis
  - 2.1.4 Conversion to nitrates
  - 2.1.5 Conversion to nitrites
3 Ecology
4 Uses
5 Human-caused sources and exposure
6 Toxicity
7 Health effects of NO2 exposure
8 Avoiding NO2 toxicity
- 8.1 Environmental limits
9 See also
10 References
11 External links

Properties

Nitrogen dioxide is a reddish-brown gas above 70 °F (21 °C; 294 K) with a pungent, acrid odor, becomes a yellowish-brown liquid below 70 °F (21 °C; 294 K), and converts to the colorless dinitrogen tetroxide (N
2O
4) below 15 °F (−9 °C; 264 K).^[5]

The bond length between the nitrogen atom and the oxygen atom is 119.7 pm. This bond length is consistent with a bond order between one and two.

Unlike ozone, O₃, the ground electronic state of nitrogen dioxide is a doublet state, since nitrogen has one unpaired electron,^[8] which decreases the alpha effect compared with nitrite and creates a weak bonding interaction with the oxygen lone pairs. The lone electron in NO
2 also means that this compound is a free radical, so the formula for nitrogen dioxide is often written as ^•NO
2.

Preparation and reactions

Nitrogen dioxide typically arises via the oxidation of nitric oxide by oxygen in air:^[9]

2 NO + O
2 → 2 NO
2

Nitrogen dioxide is formed in most combustion processes using air as the oxidant. At elevated temperatures nitrogen combines with oxygen to form nitric oxide:

O
2 + N
2 → 2 NO

In the laboratory, NO
2 can be prepared in a two-step procedure where dehydration of nitric acid produces dinitrogen pentoxide, which subsequently undergoes thermal decomposition:

2 HNO
3 → N
2O
5 + H
2O

2 N
2O
5 → 4 NO
2 + O
2

The thermal decomposition of some metal nitrates also affords NO
2:

2 Pb(NO
3)
2 → 2 PbO + 4 NO
2 + O
2

Alternatively, reduction of concentrated nitric acid by metal (such as copper).

4 HNO
3 + Cu → Cu(NO
3)
2 + 2 NO
2 + 2 H
2O

Or finally by adding concentrated nitric acid over tin; hydrated tin dioxide is produced as byproduct.

4 HNO₃ + Sn → H₂O + H₂SnO₃ + 4 NO₂

Main reactions

NO
2 is highly reactive.^[7]

Basic thermal properties

NO
2 exists in equilibrium with the colourless gas dinitrogen tetroxide (N
2O
4):

2 NO
2 ⇌ N
2O
4

The equilibrium is characterized by ΔH = −57.23 kJ/mol, which is exothermic. NO₂ is favored at higher temperatures, while at lower temperatures, dinitrogen tetroxide (N₂O₄) predominates. Dinitrogen tetroxide (N
2O
4) can be obtained as a white solid with melting point −11.2 °C.^[9] NO₂ is paramagnetic due to its unpaired electron, while N₂O₄ is diamagnetic.

The chemistry of nitrogen dioxide has been investigated extensively. At 150 °C, NO
2 decomposes with release of oxygen via an endothermic process (ΔH = 114 kJ/mol):

2 NO
2 → 2 NO + O
2

As an oxidizer

As suggested by the weakness of the N–O bond, NO
2 is a good oxidizer. Consequently, it will combust, sometimes explosively, with many compounds, such as hydrocarbons.

Hydrolysis

It hydrolyses to give nitric acid and nitrous acid:

2 NO
2/N
2O
4 + H
2O → HNO
2 + HNO
3

This reaction is one step in the Ostwald process for the industrial production of nitric acid from ammonia.^[10] Nitric acid decomposes slowly to nitrogen dioxide, which confers the characteristic yellow color of most samples of this acid:

4 HNO
3 → 4 NO
2 + 2 H
2O + O
2

Conversion to nitrates

NO
2 is used to generate anhydrous metal nitrates from the oxides:^[9]

MO + 3 NO
2 → M(NO
3)
2 + NO

Conversion to nitrites

Alkyl and metal iodides give the corresponding nitrites:

2 CH
3I + 2 NO
2 → 2 CH
3NO
2 + I
2

TiI
4 + 4 NO
2 → Ti(NO
2)
4 + 2 I
2

Ecology

NO
2 is introduced into the environment by natural causes, including entry from the stratosphere, bacterial respiration, volcanos, and lightning. These sources make NO
2 a trace gas in the atmosphere of Earth, where it plays a role in absorbing sunlight and regulating the chemistry of the troposphere, especially in determining ozone concentrations.^[11]

Uses

NO
2 is used as an intermediate in the manufacturing of nitric acid, as a nitrating agent in manufacturing of chemical explosives, as a polymerization inhibitor for acrylates, and as a flour bleaching agent.^[12]^:223 It is also used as an oxidizer in rocket fuel, for example in red fuming nitric acid; it was used in the Titan rockets, to launch Project Gemini, in the maneuvering thrusters of the Space Shuttle, and in unmanned space probes sent to various planets.^[13]

Human-caused sources and exposure

For the general public, the most prominent sources of NO
2 are internal combustion engines burning fossil fuels.^[7] Outdoors, NO
2 can be a result of traffic from motor vehicles.^[14]

Indoors, exposure arises from cigarette smoke,^[15] and butane and kerosene heaters and stoves.^[16]

Workers in industries where NO
2 is used are also exposed and are at risk for occupational lung diseases, and NIOSH has set exposure limits and safety standards.^[5] Astronauts in the Apollo–Soyuz Test Project were almost killed when NO
2 was accidentally vented into the cabin.^[13] Agricultural workers can be exposed to NO
2 arising from grain decomposing in silos; chronic exposure can lead to lung damage in a condition called "Silo-filler's disease".^[17]^[18]

Historically, nitrogen dioxide was also produced by atmospheric nuclear tests, and was responsible for the reddish colour of mushroom clouds.^[19]

Toxicity

Gaseous NO
2 diffuses into the epithelial lining fluid (ELF) of the respiratory epithelium and dissolves, and chemically reacts with antioxidant and lipid molecules in the ELF; NO
2's health effects are caused by the reaction products or their metabolites, which are reactive nitrogen species and reactive oxygen species that can drive bronchoconstriction, inflammation, reduced immune response, and may have effects on the heart.^[20]

Pathways indicated by a dotted line are those for which evidence is limited to findings from experimental animal studies, while evidence from controlled human exposure studies is available for pathways indicated by a solid line. Dashed lines indicate proposed links to the outcomes of asthma exacerbation and respiratory tract infections. Key events are subclinical effects, endpoints are effects that are generally measured in the clinic, and outcomes are health effects at the organism level. NO₂ = nitrogen dioxide; ELF = epithelial lining fluid.^[20]^:4–62

Nitrogen dioxide diffusion tube for air quality monitoring. Positioned in the City of London

Acute harm due to NO
2 exposure is only likely to arise in occupational settings. Direct exposure to the skin can cause irritations and burns. Only very high concentrations of the gaseous form cause immediate distress: 10–20 ppm can cause mild irritation of the nose and throat, 25–50 ppm can cause edema leading to bronchitis or pneumonia, and levels above 100 ppm can cause death due to asphyxiation from fluid in the lungs. There are often no symptoms at the time of exposure other than transient cough, fatigue or nausea, but over hours inflammation in the lungs causes edema.^[21]^[22]

For skin or eye exposure, the affected area is flushed with saline. For inhalation, oxygen is administered, bronchodilators may be administered, and if there are signs of methemoglobinemia, a condition that arises when nitrogen-based compounds affect the hemoglobin in red blood cells, methylene blue may be administered.^[23]^[24]

It is classified as an extremely hazardous substance in the United States as defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act (42 U.S.C. 11002), and it is subject to strict reporting requirements by facilities which produce, store, or use it in significant quantities.^[25]

Health effects of NO
2 exposure

For the public, chronic exposure to NO
2 can cause respiratory effects including airway inflammation in healthy people and increased respiratory symptoms in people with asthma. NO
2 creates ozone which causes eye irritation and exacerbates respiratory conditions, leading to increased visits to emergency departments and hospital admissions for respiratory issues, especially asthma.^[26]

The effects of toxicity on health have been examined using questionnaires and inperson interviews in an effort to understand the relationship between (NO
2) and asthma. The influence of indoor air pollutants on health is important because the majority of people in the world spend more than 80% of their time indoors.^[27] The amount of time spent indoors depends upon on several factors including geographical region, job activities, and gender among other variables. Additionally, because home insulation is improving, this can result in greater retention of indoor air pollutants, such as (NO
2) .^[27] With respect to geographic region, the prevalence of asthma has ranged from 2 to 20% with no clear indication as to what’s driving the difference.^[27] This may be a result of the “hygiene hypothesis” or "western lifestyle” that captures the notions of homes that are well insulated and with fewer inhabitants.^[27] Another study examined the relationship between nitrogen exposure in the home and respiratory symptoms and found a statistically significant odds ratio of 2.23 (95% CI: 1.06, 4.72) among those with a medical diagnosis of asthma and gas stove exposure.^[28]

A major source of indoor exposure to (NO
2) is from the use of gas stoves for cooking or heating in homes. According to the 2000 census, over half of US households use gas stoves^[29] and indoor exposure levels of (NO
2) are, on average, at least three times higher in homes with gas stoves compared to electric stoves with the highest levels being in multifamily homes. Exposure to (NO
2) is especially harmful for children with asthma. Research has shown that children with asthma who live in homes with gas stoves have greater risk of respiratory symptoms such as wheezing, cough and chest tightness.^[28]^[30] Additionally, gas stove use was associated with reduced lung function in girls with asthma, although this association was not found in boys.^[31] Using ventilation when operating gas stoves may reduce the risk of respiratory symptoms in children with asthma.

In a cohort study with inner-city minority African American Baltimore children to determine if there was a relationship between (NO
2) and asthma for children aged 2 to 6 years old, with an existing medical diagnosis of asthma, and one asthma related visit. Families of lower socioeconomic status were more likely to have gas stoves in their homes. The study concluded that that higher levels of (NO
2) within a home were linked to a greater level of respiratory symptoms among the study population. This further exemplifies that (NO
2) toxicity is dangerous for children.^[32]

Avoiding NO
2 toxicity

While using a gas stove, it is advised to also use ventilation. Studies show that in homes with gas stoves, if ventilation is used while using gas stoves, then children have lower odds of asthma, wheezing and bronchitis as compared to children in homes that never used ventilation.^[33] If venting isn’t possible, then replacing gas stoves with electric stove could be another option. Replacing gas stoves with electric ranges could greatly reduce the exposure to indoor NO₂ and improve the respiratory function of children with asthma. It is important to keep gas stoves and heaters in good repair so they are not polluting extra NO₂. 2015 International Residential Code that requires that vent hoods are used for all stoves and set standards for residential buildings. This requires that all range hoods have a vent that discharges outside. You can also prevent NO₂ exposure by avoiding cigarette smoking and not idling your car whenever possible.^[34]

Environmental limits

The U.S. EPA has set safety levels for environmental exposure to NO
2 at 100 ppb, averaged over one hour, and 53 ppb, averaged annually.^[7] As of February 2016, no area of the US was out of compliance with these limits and concentrations ranged between 10–20 ppb, and annual average ambient NO₂ concentrations, as measured at area-wide monitors, have decreased by more than 40% since 1980.^[30]

However, NO
2 concentrations in vehicles and near roadways are appreciably higher than those measured at monitors in the current network. In fact, in-vehicle concentrations can be 2–3 times higher than measured at nearby area-wide monitors. Near-roadway (within about 50 metres (160 ft)) concentrations of NO₂ have been measured to be approximately 30 to 100% higher than concentrations away from roadways. Individuals who spend time on or near major roadways can experience short-term NO₂ exposures considerably higher than measured by the current network. Approximately 16% of U.S. housing units are located within 300 feet (91 m) of a major highway, railroad, or airport (approximately 48 million people). This population likely includes a higher proportion of non-white and economically-disadvantaged people. Studies show a connection between breathing elevated short-term NO₂ concentrations, and increased visits to emergency departments and hospital admissions for respiratory issues, especially asthma. NO₂ exposure concentrations near roadways are of particular concern for susceptible individuals, including asthmatics, children, and the elderly.^[26]

For limits in other countries see the table in the Ambient air quality criteria article.

References

^ "nitrogen dioxide (CHEBI:33101)". Chemical Entities of Biological Interest (ChEBI). UK: European Bioinformatics Institute. 13 January 2008. Main. Retrieved 4 October 2011.
^ Haynes, William M., ed. (2011). CRC Handbook of Chemistry and Physics (92nd ed.). CRC Press. p. 4.79. ISBN 1439855110.
^ Mendiara, S. N.; Sagedahl, A.; Perissinotti, L. J. (2001). "An electron paramagnetic resonance study of nitrogen dioxide dissolved in water, carbon tetrachloride and some organic compounds". Applied Magnetic Resonance. 20: 275. doi:10.1007/BF03162326.
^ ^a ^b Zumdahl, Steven S. (2009). Chemical Principles 6th Ed. Houghton Mifflin Company. p. A22. ISBN 0-618-94690-X.
^ ^a ^b ^c ^d ^e "NIOSH Pocket Guide to Chemical Hazards #0454". National Institute for Occupational Safety and Health (NIOSH).
^ ^a ^b "Nitrogen dioxide". Immediately Dangerous to Life and Health. National Institute for Occupational Safety and Health (NIOSH).
^ ^a ^b ^c ^d This article incorporates public domain material from the United States Environmental Protection Agency document: "Nitrogen dioxide". United States Environmental Protection Agency. Feb 23, 2016.
^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 455. ISBN 0-08-037941-9.
^ ^a ^b ^c Holleman, A. F.; Wiberg, E. (2001) Inorganic Chemistry. Academic Press: San Diego. ISBN 0-12-352651-5.
^ Thiemann, Michael; Scheibler, Erich and Wiegand, Karl Wilhelm (2005) "Nitric Acid, Nitrous Acid, and Nitrogen Oxides" in Ullmann’s Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim doi:10.1002/14356007.a17_293.
^ WHO Air Quality Guidelines - Second Edition. Chapter 7.1 Nitrogen Dioxide
^ Subcommittee on Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants; Committee on Toxicology; Board on Environmental Studies and Toxicology; Division on Earth and Life Studies; National Research Council. Chapter 12: Nitrogen Dioxide in Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants. National Academies Press, 2007. ISBN 978-0-309-09225-8
^ ^a ^b Cotton, Simon (21 March 2013) Nitrogen dioxide. RSC Chemistry World
^ "WHO | Air quality guidelines - global update 2005". www.who.int. Retrieved 2016-10-19.
^ US Dept. of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry, Division of Toxicology. April 2002 ATSDR Nitrous Oxides
^ "The Impact of Unvented Gas Heating Appliances on Indoor Nitrogen Dioxide Levels in 'TIGHT' Homes". ashrae.org. Retrieved 2013-04-11.
^ Chan-Yeung, M.; Ashley, M. J.; Grzybowski, S. (1978). "Grain dust and the lungs". Canadian Medical Association journal. 118 (10): 1271–4. PMC 1818652 . PMID 348288.
^ Gurney, J. W.; Unger, J. M.; Dorby, C. A.; Mitby, J. K.; von Essen, S. G. (1991). "Agricultural disorders of the lung". Radiographics : a review publication of the Radiological Society of North America, Inc. 11 (4): 625–34. doi:10.1148/radiographics.11.4.1887117. PMID 1887117.
^ Effects of Nuclear Explosions. Nuclearweaponarchive.org. Retrieved on 2010-02-08.
^ ^a ^b U.S. EPA. Integrated Science Assessment for Oxides of Nitrogen – Health Criteria (2016 Final Report). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-15/068, 2016. Federal Register Notice Jan 28, 2016 Free download available at Report page at EPA website.
^ Toxnet Nitrogen dioxide: Human Health Effects Page accessed March 28, 2016
^ CDC NIOSH International Chemical Safety Cards (ICSC): Nitrogen Dioxide Page last reviewed: July 22, 2015; Page last updated: July 1, 2014
^ Agency for Toxic Substances and Disease Registry via the CDC Medical Management Guidelines for Nitrogen Oxides Page last reviewed: October 21, 2014; Page last updated: October 21, 2014
^ University of Kansas Hospital, Poison Control Center Poison Facts: Medium Chemicals: Nitrogen Dioxide page accessed March 28, 2016
^ "40 C.F.R.: Appendix A to Part 355—The List of Extremely Hazardous Substances and Their Threshold Planning Quantities" (PDF) (July 1, 2008 ed.). Government Printing Office. Retrieved October 29, 2011.
^ ^a ^b This article incorporates public domain material from the United States Environmental Protection Agency document "Nitrogen Dioxide: Health" (retrieved on 2/23/2016).
^ ^a ^b ^c ^d Heinrich, Joachim (2011-01-01). "Influence of indoor factors in dwellings on the development of childhood asthma". International Journal of Hygiene and Environmental Health. 214 (1): 1–25. doi:10.1016/j.ijheh.2010.08.009. PMID 20851050.
^ ^a ^b Garrett, Maria H.; Hooper, Martin A.; Hooper, Beverley M.; Abramson, Michael J. (1998-09-01). "Respiratory Symptoms in Children and Indoor Exposure to Nitrogen Dioxide and Gas Stoves". American Journal of Respiratory and Critical Care Medicine. 158 (3): 891–895. doi:10.1164/ajrccm.158.3.9701084.
^ "Historical Census of Housing Tables -House Heating Fuel". www.census.gov. Retrieved 2016-10-19.
^ ^a ^b This article incorporates public domain material from the United States Environmental Protection Agency document "Nitrogen Dioxide Basic Information" (retrieved on 2/23/2016).
^ Chapman, Robert S.; Hadden, Wilbur C.; Perlin, Susan A. (2003-07-15). "Influences of asthma and household environment on lung function in children and adolescents: the third national health and nutrition examination survey". American Journal of Epidemiology. 158 (2): 175–189. PMID 12851231.
^ Hansel, Nadia N.; Breysse, Patrick N.; McCormack, Meredith C.; Matsui, Elizabeth C.; Curtin-Brosnan, Jean; Williams, D’Ann L.; Moore, Jennifer L.; Cuhran, Jennifer L.; Diette, Gregory B. (2016-10-19). "A Longitudinal Study of Indoor Nitrogen Dioxide Levels and Respiratory Symptoms in Inner-City Children with Asthma". Environmental Health Perspectives. 116 (10): 1428–1432. doi:10.1289/ehp.11349. PMC 2569107 . PMID 18941590.
^ Kile, Molly L; Coker, Eric S; Smit, Ellen; Sudakin, Daniel; Molitor, John; Harding, Anna K (2014-09-02). "A cross-sectional study of the association between ventilation of gas stoves and chronic respiratory illness in U.S. children enrolled in NHANESIII". Environmental Health. 13: 71. doi:10.1186/1476-069X-13-71. PMC 4175218 . PMID 25182545.
^ "Healthy Child Healthy World |". Healthy Child Healthy World. Retrieved 2016-10-19.

External links

International Chemical Safety Card 0930
National Pollutant Inventory – Oxides of nitrogen fact sheet
NIOSH Pocket Guide to Chemical Hazards
WHO-Europe reports: Health Aspects of Air Pollution (2003) (PDF) and "Answer to follow-up questions from CAFE (2004) (PDF)
Nitrogen Dioxide Air Pollution
Nitrogen dioxide pollution in the world (image)
A review of the acute and long term impacts of exposure to nitrogen dioxide in the United Kingdom IOM Research Report TM/04/03

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★リンクテーブル★

リンク元	「二酸化窒素」「NO2」
関連記事	「nitrogen」「dioxide」

「二酸化窒素」

Nitrogen dioxide
	; Nitrogen dioxide at −196 °C, 0 °C, 23 °C, 35 °C, and 50 °C. (NO; 2) converts to the colorless dinitrogen tetroxide (N; 2O; 4) at low temperatures, and reverts to NO; 2 at higher temperatures.
Names
	IUPAC name Nitrogen dioxide
	Other names Nitrogen(IV) oxide, Deutoxide of nitrogen
Identifiers
CAS Number	10102-44-0 ;
3D model (Jmol)	Interactive image; Interactive image;
ChEBI	CHEBI:33101 ;
ChemSpider	2297499 ;
ECHA InfoCard	100.030.234
EC Number	233-272-6
Gmelin Reference	976
PubChem CID	3032552;
RTECS number	QW9800000
UNII	S7G510RUBH ;
UN number	1067
	InChI InChI=1S/NO2/c2-1-3 Key: JCXJVPUVTGWSNB-UHFFFAOYSA-N ; InChI=1/NO2/c2-1-3 Key: JCXJVPUVTGWSNB-UHFFFAOYAA ;
	SMILES N(=O)[O] ; [N+](=O)[O-] ;
Properties
Chemical formula	NO•; 2
Molar mass	46.0055 g mol−1
Appearance	Vivid orange gas
Odor	Chlorine like
Density	1.88 g dm−3
Melting point	−11.2 °C (11.8 °F; 261.9 K)
Boiling point	21.2 °C (70.2 °F; 294.3 K)
Solubility in water	Hydrolyses
Solubility	soluble in CCl; 4, nitric acid, chloroform
Vapor pressure	98.80 kPa (at 20 °C)
Magnetic susceptibility (χ)	+150.0·10−6 cm3/mol
Refractive index (nD)	1.449 (at 20 °C)
Structure
Point group	C2v
Molecular shape	Bent
Thermochemistry
Specific; heat capacity (C)	37.5 J/mol K
Std molar; entropy (So298)	240 J mol−1 K−1
Std enthalpy of; formation (ΔfHo298)	+34 kJ mol−1
Hazards
Main hazards	Poison, oxidizer
Safety data sheet	ICSC 0930
GHS pictograms
GHS signal word	Danger
GHS hazard statements	H270, H314, H330
GHS precautionary statements	P220, P260, P280, P284, P305+351+338, P310
EU classification (DSD)	O T+
R-phrases	R26, R34, R8
S-phrases	(S1/2), S9, S26, S28, S36/37/39, S45
NFPA 704	0 3 2 OX
	Lethal dose or concentration (LD, LC):
LC50 (median concentration)	30 ppm (guinea pig, 1 hr); 315 ppm (rabbit, 15 min); 68 ppm (rat, 4 hr); 138 ppm (rat, 30 min); 1000 ppm (mouse, 10 min)
LCLo (lowest published)	64 ppm (dog, 8 hr); 64 ppm (monkey, 8 hr)
	US health exposure limits (NIOSH):
PEL (Permissible)	C 5 ppm (9 mg/m3)
REL (Recommended)	ST 1 ppm (1.8 mg/m3)
IDLH (Immediate danger)	20 ppm
Related compounds
Related nitrogen oxides	Dinitrogen pentoxide; Dinitrogen tetroxide; Dinitrogen trioxide; Nitric oxide; Nitrous oxide
Related compounds	Chlorine dioxide; Carbon dioxide
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
	verify (what is ?)
	Infobox references

　　[★]

英: nitrogen dioxide、NO2
関: 窒素酸化物 NOX

発生源：(環境)工場のボイラー、自動車の排気ガス、(学校)ストーブ

「NO2」

　　[★] 二酸化窒素, nitrogen dioxide

「nitrogen」

　　[★]

n.

窒素

関: N、N2、nitric

「dioxide」

　　[★]

二酸化物、ジオキシド　　

[nitrogen_dioxide_.28CHEBI:33101.29-1] "nitrogen dioxide (CHEBI:33101)". Chemical Entities of Biological Interest (ChEBI). UK: European Bioinformatics Institute. 13 January 2008. Main. Retrieved 4 October 2011.

[2] Haynes, William M., ed. (2011). CRC Handbook of Chemistry and Physics (92nd ed.). CRC Press. p. 4.79. ISBN 1439855110.

[3] Mendiara, S. N.; Sagedahl, A.; Perissinotti, L. J. (2001). "An electron paramagnetic resonance study of nitrogen dioxide dissolved in water, carbon tetrachloride and some organic compounds". Applied Magnetic Resonance. 20: 275. doi:10.1007/BF03162326.

[b1-4] Zumdahl, Steven S. (2009). Chemical Principles 6th Ed. Houghton Mifflin Company. p. A22. ISBN 0-618-94690-X.

[PGCH-5] "NIOSH Pocket Guide to Chemical Hazards #0454". National Institute for Occupational Safety and Health (NIOSH).

[IDLH-6] "Nitrogen dioxide". Immediately Dangerous to Life and Health. National Institute for Occupational Safety and Health (NIOSH).

[EPAmain-7] This article incorporates public domain material from the United States Environmental Protection Agency document: "Nitrogen dioxide". United States Environmental Protection Agency. Feb 23, 2016.

[8] Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 455. ISBN 0-08-037941-9.

[Holleman-9] Holleman, A. F.; Wiberg, E. (2001) Inorganic Chemistry. Academic Press: San Diego. ISBN 0-12-352651-5.

[10] Thiemann, Michael; Scheibler, Erich and Wiegand, Karl Wilhelm (2005) "Nitric Acid, Nitrous Acid, and Nitrogen Oxides" in Ullmann’s Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim doi:10.1002/14356007.a17_293.

[11] WHO Air Quality Guidelines - Second Edition. Chapter 7.1 Nitrogen Dioxide

[12] Subcommittee on Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants; Committee on Toxicology; Board on Environmental Studies and Toxicology; Division on Earth and Life Studies; National Research Council. Chapter 12: Nitrogen Dioxide in Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants. National Academies Press, 2007. ISBN 978-0-309-09225-8

[ChemWorld-13] Cotton, Simon (21 March 2013) Nitrogen dioxide. RSC Chemistry World

[14] "WHO | Air quality guidelines - global update 2005". www.who.int. Retrieved 2016-10-19.

[ATSDR-15] US Dept. of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry, Division of Toxicology. April 2002 ATSDR Nitrous Oxides

[16] "The Impact of Unvented Gas Heating Appliances on Indoor Nitrogen Dioxide Levels in 'TIGHT' Homes". ashrae.org. Retrieved 2013-04-11.

[17] Chan-Yeung, M.; Ashley, M. J.; Grzybowski, S. (1978). "Grain dust and the lungs". Canadian Medical Association journal. 118 (10): 1271–4. PMC 1818652 . PMID 348288.

[18] Gurney, J. W.; Unger, J. M.; Dorby, C. A.; Mitby, J. K.; von Essen, S. G. (1991). "Agricultural disorders of the lung". Radiographics : a review publication of the Radiological Society of North America, Inc. 11 (4): 625–34. doi:10.1148/radiographics.11.4.1887117. PMID 1887117.

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[EPAassess2016-20] U.S. EPA. Integrated Science Assessment for Oxides of Nitrogen – Health Criteria (2016 Final Report). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-15/068, 2016. Federal Register Notice Jan 28, 2016 Free download available at Report page at EPA website.

[ToxnetHH-21] Toxnet Nitrogen dioxide: Human Health Effects Page accessed March 28, 2016

[22] CDC NIOSH International Chemical Safety Cards (ICSC): Nitrogen Dioxide Page last reviewed: July 22, 2015; Page last updated: July 1, 2014

[23] Agency for Toxic Substances and Disease Registry via the CDC Medical Management Guidelines for Nitrogen Oxides Page last reviewed: October 21, 2014; Page last updated: October 21, 2014

[24] University of Kansas Hospital, Poison Control Center Poison Facts: Medium Chemicals: Nitrogen Dioxide page accessed March 28, 2016

[gov-right-know-25] "40 C.F.R.: Appendix A to Part 355—The List of Extremely Hazardous Substances and Their Threshold Planning Quantities" (PDF) (July 1, 2008 ed.). Government Printing Office. Retrieved October 29, 2011.

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[31] Chapman, Robert S.; Hadden, Wilbur C.; Perlin, Susan A. (2003-07-15). "Influences of asthma and household environment on lung function in children and adolescents: the third national health and nutrition examination survey". American Journal of Epidemiology. 158 (2): 175–189. PMID 12851231.

[32] Hansel, Nadia N.; Breysse, Patrick N.; McCormack, Meredith C.; Matsui, Elizabeth C.; Curtin-Brosnan, Jean; Williams, D’Ann L.; Moore, Jennifer L.; Cuhran, Jennifer L.; Diette, Gregory B. (2016-10-19). "A Longitudinal Study of Indoor Nitrogen Dioxide Levels and Respiratory Symptoms in Inner-City Children with Asthma". Environmental Health Perspectives. 116 (10): 1428–1432. doi:10.1289/ehp.11349. PMC 2569107 . PMID 18941590.

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v t e Oxides

Mixed oxidation states	Antimony tetroxide (Sb₂O₄) Cobalt(II,III) oxide (Co₃O₄) Iron(II,III) oxide (Fe₃O₄) Lead(II,IV) oxide (Pb₃O₄) Manganese(II,III) oxide (Mn₃O₄) Silver(I,III) oxide (Ag₂O₂) Triuranium octoxide (U₃O₈) Carbon suboxide (C₃O₂) Mellitic anhydride (C₁₂O₉)

+1 oxidation state	Copper(I) oxide (Cu₂O) Dicarbon monoxide (C₂O) Dichlorine monoxide (Cl₂O) Gallium(I) oxide (Ga₂O) Lithium oxide (Li₂O) Potassium oxide (K₂O) Rubidium oxide (Rb₂O) Silver oxide ([Ag₂O) Thallium(I) oxide (Tl₂O) Sodium oxide (Na₂O) Water (hydrogen oxide) (H₂O)

+2 oxidation state	Aluminium(II) oxide (AlO) Barium oxide (BaO) Beryllium oxide (BeO) Cadmium oxide (CdO) Calcium oxide (CaO) Carbon monoxide (CO) Chromium(II) oxide (CrO) Cobalt(II) oxide (CoO) Copper(II) oxide (CuO) Iron(II) oxide (FeO) Lead(II) oxide (PbO) Magnesium oxide (MgO) Mercury(II) oxide (HgO) Nickel(II) oxide (NiO) Nitric oxide (NO) Palladium(II) oxide (PdO) Strontium oxide (SrO) Sulfur monoxide (SO) Disulfur dioxide (S₂O₂) Tin(II) oxide (SnO) Titanium(II) oxide (TiO) Vanadium(II) oxide (VO) Zinc oxide (ZnO)

+3 oxidation state	Aluminium oxide (Al₂O₃) Antimony trioxide (Sb₂O₃) Arsenic trioxide (As₂O₃) Bismuth(III) oxide (Bi₂O₃) Boron trioxide (B₂O₃) Chromium(III) oxide (Cr₂O₃) Dinitrogen trioxide (N₂O₃) Erbium(III) oxide (Er₂O₃) Gadolinium(III) oxide (Gd₂O₃) Gallium(III) oxide (Ga₂O₃) Holmium(III) oxide (Ho₂O₃) Indium(III) oxide (In₂O₃) Iron(III) oxide (Fe₂O₃) Lanthanum oxide (La₂O₃) Lutetium(III) oxide (Lu₂O₃) Nickel(III) oxide (Ni₂O₃) Phosphorus trioxide (P₄O₆) Promethium(III) oxide (Pm₂O₃) Rhodium(III) oxide (Rh₂O₃) Samarium(III) oxide (Sm₂O₃) Scandium oxide (Sc₂O₃) Terbium(III) oxide (Tb₂O₃) Thallium(III) oxide (Tl₂O₃) Thulium(III) oxide (Tm₂O₃) Titanium(III) oxide (Ti₂O₃) Tungsten(III) oxide (W₂O₃) Vanadium(III) oxide (V₂O₃) Ytterbium(III) oxide (Yb₂O₃) Yttrium(III) oxide (Y₂O₃)

+4 oxidation state	Carbon dioxide (CO₂) Carbon trioxide (CO₃) Cerium(IV) oxide (CeO₂) Chlorine dioxide (ClO₂) Chromium(IV) oxide (CrO₂) Dinitrogen tetroxide (N₂O₄) Germanium dioxide (GeO₂) Hafnium(IV) oxide (HfO₂) Lead dioxide (PbO₂) Manganese dioxide (MnO₂) Nitrogen dioxide (NO₂) Plutonium(IV) oxide (PuO₂) Rhodium(IV) oxide (RhO₂) Ruthenium(IV) oxide (RuO₂) Selenium dioxide (SeO₂) Silicon dioxide (SiO₂) Sulfur dioxide (SO₂) Tellurium dioxide (TeO₂) Thorium dioxide (ThO₂) Tin dioxide (SnO₂) Titanium dioxide (TiO₂) Tungsten(IV) oxide (WO₂) Uranium dioxide (UO₂) Vanadium(IV) oxide (VO₂) Zirconium dioxide (ZrO₂)

+5 oxidation state	Antimony pentoxide (Sb₂O₅) Arsenic pentoxide (As₂O₅) Dinitrogen pentoxide (N₂O₅) Niobium pentoxide (Nb₂O₅) Phosphorus pentoxide (P₂O₅) Tantalum pentoxide (Ta₂O₅) Vanadium(V) oxide (V₂O₅)

+6 oxidation state	Chromium trioxide (CrO₃) Molybdenum trioxide (MoO₃) Rhenium trioxide (ReO₃) Selenium trioxide (SeO₃) Sulfur trioxide (SO₃) Tellurium trioxide (TeO₃) Tungsten trioxide (WO₃) Uranium trioxide (UO₃) Xenon trioxide (XeO₃)

+7 oxidation state	Dichlorine heptoxide (Cl₂O₇) Manganese heptoxide (Mn₂O₇) Rhenium(VII) oxide (Re₂O₇) Technetium(VII) oxide (Tc₂O₇)

+8 oxidation state	Osmium tetroxide (OsO₄) Ruthenium tetroxide (RuO₄) Xenon tetroxide (XeO₄) Iridium tetroxide (IrO₄) Hassium tetroxide (HsO₄)

Related	Oxocarbon Suboxide Oxyanion Ozonide

Oxides are sorted by oxidation state. Category:Oxides

匿名

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案内

nitrogen dioxide

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Contents

Properties

Preparation and reactions

Main reactions

Basic thermal properties

As an oxidizer

Hydrolysis

Conversion to nitrates

Conversion to nitrites

Ecology

Uses

Human-caused sources and exposure

Toxicity

Health effects of NO
2 exposure

Avoiding NO
2 toxicity

Environmental limits

See also

References

External links

UpToDate Contents

English Journal

Japanese Journal

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「二酸化窒素」

「NO2」

「nitrogen」

「dioxide」

v t e Nitrogen species

Hydrides: NH₃ NH₄⁺ NH₂⁻ N³⁻ N₂H₄ N₃^– Organic: -NH₂ HCN CN⁻ C₂N₂ H₂NCN CH₂N₂ Oxides: N₂O NO NO₂ N₂O₃ N₂O₄ N₂O₅ HNO₂ HNO₃ NO₂⁻ NO₃⁻ Halides: NF₃ NCl₃ ClN₃

Chemical formulas

v t e Oxygen compounds

AgO Al₂O₃ AmO₂ Am₂O₃ As₂O₃ As₂O₅ Au₂O₃ B₂O₃ BaO BeO Bi₂O₃ BiO₂ Bi₂O₅ BrO₂ Br₂O₃ Br₂O₅ CO CO₂ C₂O₃ CaO CaO₂ CdO CeO₂ Ce₂O₃ ClO₂ Cl₂O Cl₂O₃ Cl₂O₄ Cl₂O₆ Cl₂O₇ CoO Co₂O₃ Co₃O₄ CrO₃ Cr₂O₃ Cr₂O₅ Cr₅O₁₂ CsO₂ Cs₂O₃ CuO D₂O Dy₂O₃ Er₂O₃ Eu₂O₃ F₂O F₂O₂ F₂O₄ FeO Fe₂O₃ Fe₃O₄ Ga₂O Ga₂O₃ GeO GeO₂ H₂O H₂¹⁸O H₂O₂ HfO₂ HgO Hg₂O Ho₂O₃ I₂O₄ I₂O₅ I₂O₆ I₄O₉ In₂O₃ InO₂ KO₂ K₂O₂ La₂O₃ Li₂O Li₂O₂ Lu₂O₃ MgO Mg₂O₃ MnO MnO₂ Mn₂O₃ Mn₂O₇ MoO₂ MoO₃ Mo₂O₃ NO NO₂ N₂O N₂O₃ N₂O₄ N₂O₅ NaO₂ Na₂O Na₂O₂ NbO NbO₂ Nd₂O₃

Chemical formulas

匿名

検索

案内

nitrogen dioxide

WordNet

PrepTutorEJDIC

Wikipedia preview

wiki en

Contents

Properties

Preparation and reactions

Main reactions

Basic thermal properties

As an oxidizer

Hydrolysis

Conversion to nitrates

Conversion to nitrites

Ecology

Uses

Human-caused sources and exposure

Toxicity

Health effects of NO 2 exposure

Avoiding NO 2 toxicity

Environmental limits

See also

References

External links

UpToDate Contents

English Journal

Japanese Journal

Related Links

Related Pictures

★リンクテーブル★

「二酸化窒素」

「NO2」

「nitrogen」

「dioxide」

Health effects of NO
2 exposure

Avoiding NO
2 toxicity