Editing Nitrous oxide (section)

{{Short description|Colourless non-flammable greenhouse gas}}
{{cs1 config|name-list-style=vanc|display-authors=6}}
{{see also|Recreational use of nitrous oxide|Nitrous oxide (medication)}}
{{Redirect|N2O|3=Nitrous oxide (disambiguation)|4=and|5=N2O (disambiguation)}}
{{Redirect|Laughing gas}}
{{Distinguish|text=[[nitric oxide]] ({{chem|NO}}), [[nitrogen dioxide]] ({{chem|NO|2}}), or generic nitrogen oxide pollutants [[NOx]]}}
{{Use British English|date=December 2018}}
{{Use dmy dates|date=December 2018}}
{{Chembox
| Verifiedfields = changed
| Watchedfields  = changed
| verifiedrevid  = 477162830
| ImageFile_Ref  = {{chemboximage|correct|??}}
| Name           = 
| ImageFile      = Nitrous-oxide-2D-VB.svg
| ImageClass     = skin-invert-image
| ImageName      = Nitrous oxide's canonical forms
| ImageFile1     = Nitrous-oxide-dimensions-3D-balls.png
| ImageClass1    = bg-transparent
| ImageName1     = Ball-and-stick model with bond lengths
| ImageFile2     = Nitrous-oxide-3D-vdW.png
| ImageClass2    = bg-transparent
| ImageSize2     = 150px
| ImageName2     = Space-filling model of nitrous oxide
| SystematicName = Oxidodinitrogen(''N—N'')
| IUPACName      = Nitrous oxide<ref>{{Cite web|url=https://www.degruyter.com/database/IUPAC/entry/iupac.compound.948/html|title=[Nitrous oxide]|website=Degruyter.com|access-date=24 July 2022}}</ref> ''(not recommended)''<br />Dinitrogen oxide<ref>[[IUPAC nomenclature of inorganic chemistry 2005]]. [http://old.iupac.org/publications/books/rbook/Red_Book_2005.pdf PDF], p. 317.</ref> ''(alternative name)''
| OtherNames     = {{Unbulleted list|Laughing gas|galaxy gas|sweet air||nitrous|nos|nang|nitrus{{cn|date=October 2024}}|protoxide of nitrogen|hyponitrous oxide|dinitrogen oxide|dinitrogen monoxide|nitro}}
| Section1       = {{Chembox Identifiers
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = K50XQU1029
| InChI1 = 1/N2O/c1-2-3
| InChIKey1 = GQPLMRYTRLFLPF-UHFFFAOYAP
| SMILES = N#[N+][O-]
| SMILES1 = [N-]=[N+]=O
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/N2O/c1-2-3
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = GQPLMRYTRLFLPF-UHFFFAOYSA-N
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo = 10024-97-2
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 923
| ChEMBL_Ref = {{ebicite|changed|EBI}}
| ChEMBL = 1234579
| DrugBank_Ref = {{drugbankcite|changed|drugbank}}
| DrugBank = DB06690
| PubChem = 948
| InChI = 1/N2O/c1-2-3
| UNNumber = 1070 (compressed)<br />2201 (liquid)
| RTECS = QX1350000
| MeSHName =
| ChEBI_Ref = {{ebicite|correct|EBI}}
| ChEBI = 17045
| KEGG_Ref = {{keggcite|correct|kegg}}
| KEGG = D00102
| Beilstein = 8137358
| Gmelin = 2153410
 }}
| Section2       = {{Chembox Properties
| Formula = {{chem|N|2|O}}
| MolarMass = 44.013 g/mol
| Appearance = colourless gas
| Density = 1.977 g/L (gas)
| MeltingPtC = −90.86
| MeltingPt_notes =
| BoilingPtC = −88.48
| BoilingPt_notes =
| Solubility = 1.5 g/L (15 °C)
| SolubleOther = soluble in [[ethanol|alcohol]], [[diethyl ether|ether]], [[sulfuric acid]]
| LogP = 0.35
| RefractIndex = 1.000516 (0 °C, 101.325 kPa)
| Viscosity = 14.90 μPa·s<ref name="TakahashiShibasaki-Kitakawa1996">{{cite journal|last1=Takahashi|first1=Mitsuo|last2=Shibasaki-Kitakawa|first2=Naomi|last3=Yokoyama|first3=Chiaki|last4=Takahashi|first4=Shinji|title=Viscosity of Gaseous Nitrous Oxide from 298.15 K to 398.15 K at Pressures up to 25 MPa|journal=Journal of Chemical & Engineering Data|volume=41|issue=6|year=1996|pages=1495–1498|issn=0021-9568|doi=10.1021/je960060d}}</ref>
| VaporPressure = 5150 kPa (20 °C)
| HenryConstant =
| AtmosphericOHRateConstant =
| MagSus = −18.9·10<sup>−6</sup> cm<sup>3</sup>/mol
 }}
| Section3       = {{Chembox Structure
| MolShape = linear, ''C''{{ssub|∞v}}
| Dipole = 0.166 [[Debye|D]]
 }}
| Section4       = 
| Section5       = {{Chembox Thermochemistry
| DeltaHf = +82.05 kJ/mol
| Entropy = 219.96 J/(K·mol)
 }}
| Section6       = {{Chembox Pharmacology
| ATCCode_prefix = N01
| ATCCode_suffix = AX13
| AdminRoutes = [[Inhalation]]
| Bioavail =
| Metabolism = 0.004%
| HalfLife = 5 minutes
| ProteinBound =
| Excretion = [[Respiratory]]
| Legal_status = <!-- All U.S. states except for [[California]] allow nitrous oxide as an [[anaesthetic]]. Also used in the [[United Kingdom]] and [[Australia]]. -->
| Legal_US =
| Legal_US_comment =
| Legal_UK =
| Legal_AU =
| Legal_CA =
| Pregnancy_category =
| Pregnancy_AU =
 }}
| Section7       = {{Chembox Hazards
| ExternalSDS = [http://www.inchem.org/documents/icsc/icsc/eics0067.htm Ilo.org], ICSC 0067
| GHSPictograms = {{GHS flame over circle}}
| GHSSignalWord = Danger
| HPhrases = {{H-phrases|270}}
| PPhrases = {{P-phrases|220|244|282|336|317|370+376|403|410+403}}
| MainHazards =
| NFPA-H = 2
| NFPA-F = 0
| NFPA-R = 0
| NFPA-S = OX
| FlashPt = Nonflammable
| LD50 =
| PEL =
 }}
| Section8       = {{Chembox Related
| OtherFunction = [[Nitric oxide]]<br />[[Dinitrogen trioxide]]<br />[[Nitrogen dioxide]]<br />[[Dinitrogen tetroxide]]<br />[[Dinitrogen pentoxide]]
| OtherFunction_label = [[nitrogen]] [[oxide]]s
| OtherCompounds = [[Ammonium nitrate]]<br />[[Azide]]
 }}
}}

'''Nitrous oxide''' (dinitrogen oxide or dinitrogen monoxide), commonly known as '''laughing gas''', '''nitrous''', or '''factitious air''', among others,<ref name="pubchem">{{Cite web |publisher=PubChem, US National Library of Medicine |title=Nitrous oxide |date=14 September 2024|url=https://pubchem.ncbi.nlm.nih.gov/compound/948 |access-date=20 September 2024 |language=en}}</ref> is a [[chemical compound]], an [[Nitrogen oxide|oxide of nitrogen]] with the [[Chemical formula|formula]] '''{{chem|N|2|O}}'''. At room temperature, it is a colourless [[Flammability#Definitions|non-flammable]] [[gas]], and has a slightly sweet scent and taste.<ref name=pubchem/> At elevated temperatures, nitrous oxide is a powerful [[Oxidising agent|oxidiser]] similar to molecular oxygen.<ref name=pubchem/>

Nitrous oxide has significant [[Nitrous oxide (medication)|medical uses]], especially in [[surgery]] and [[dentistry]], for its [[Anesthesia|anaesthetic]] and [[Analgesic|pain-reducing]] effects,<ref name="ACB 2020">{{cite journal |author1-last=Quax |author1-first=Marcel L. J. |author2-last=Van Der Steenhoven |author2-first=Timothy J. |author3-last=Bronkhorst |author3-first=Martinus W. G. A. |author4-last=Emmink |author4-first=Benjamin L. |date=July 2020 |title=Frostbite injury: An unknown risk when using nitrous oxide as a party drug |journal=Acta Chirurgica Belgica |publisher=[[Taylor & Francis]] on behalf of the Royal Belgian Society for Surgery |volume=120 |issue=1–4 |pages=140–143 |doi=10.1080/00015458.2020.1782160 |issn=0001-5458 |pmid=32543291 |s2cid=219702849}}</ref> and it is on the [[WHO Model List of Essential Medicines|World Health Organization's List of Essential Medicines]].<ref name="WHO21st">{{cite book |last1=Organization |first1=World Health |title=World Health Organization model list of essential medicines: 21st list 2019 |publisher=World Health Organization |year=2019 |location=Geneva |hdl=10665/325771 |hdl-access=free}}</ref> Its colloquial name, "laughing gas", coined by [[Humphry Davy]], describes the [[Euphoria|euphoric]] effects upon inhaling it, which cause it to be used as a [[recreational drug]] inducing a brief "[[Dissociative|high]]".<ref name="ACB 2020"/><ref>{{Cite web |last=Turner |first=Sally |date=2024-08-30 |title=Nitrous-Oxide: What is it good for? |url=https://www.drugscience.org.uk/nitrous-oxide-what-is-it-good-for |access-date=2024-10-03 |website=Drug Science |language=en}}</ref> When abused chronically, it may cause neurological damage through inactivation of [[Vitamin B12|vitamin B<sub>12</sub>]]. It is also used as an oxidiser in [[rocket propellant]]s and [[auto racing|motor racing]] fuels, and as a [[Aerosol spray#Aerosol propellants|frothing gas]] for whipped cream.

Nitrous oxide is also an [[Air pollution|atmospheric pollutant]], with a concentration of 333&nbsp;[[Parts-per notation|parts per billion]] (ppb) in 2020, increasing at 1&nbsp;ppb annually.<ref name="agage" /><ref name="noaaesrl" /> It is a major scavenger of [[ozone layer|stratospheric ozone]], with an impact comparable to that of [[chlorofluorocarbon|CFCs]].<ref name="sciozo"/> About 40% of human-caused emissions are [[Greenhouse gas emissions from agriculture#Nitrous oxide emissions|from agriculture]],<ref name="HTian">{{cite journal |last1=Tian |first1=Hanqin |last2=Xu |first2=Rongting |last3=Canadell |first3=Josep G. |last4=Thompson |first4=Rona L. |last5=Winiwarter |first5=Wilfried |last6=Suntharalingam |first6=Parvadha |last7=Davidson |first7=Eric A. |last8=Ciais |first8=Philippe |last9=Jackson |first9=Robert B. |last10=Janssens-Maenhout |first10=Greet |date=October 2020 |title=A comprehensive quantification of global nitrous oxide sources and sinks |url=https://www.nature.com/articles/s41586-020-2780-0 |url-status=bot: unknown |journal=Nature |language=en |volume=586 |issue=7828 |pages=248–256 |bibcode=2020Natur.586..248T |doi=10.1038/s41586-020-2780-0 |issn=1476-4687 |pmid=33028999 |hdl=1871.1/c74d4b68-ecf4-4c6d-890d-a1d0aaef01c9 |s2cid=222217027 |archive-url=https://web.archive.org/web/20201203131716/https://www.nature.com/articles/s41586-020-2780-0 |archive-date=3 December 2020 |access-date=2020-11-09|hdl-access=free }}</ref><ref name=":0">{{cite journal |author=Thompson, R. L. |author2=Lassaletta, L. |author3=Patra, P. K. |title=Acceleration of global N<sub>2</sub>O emissions seen from two decades of atmospheric inversion |journal=Nat. Clim. Change |year=2019 |volume=9 |issue=12 |pages=993–998 |doi=10.1038/s41558-019-0613-7|bibcode=2019NatCC...9..993T |s2cid=208302708 |url=http://pure.iiasa.ac.at/id/eprint/16173/2/N2O_paper_SI_revision2_v1.docx|hdl=11250/2646484 |hdl-access=free }}</ref> as nitrogen fertilisers are digested into nitrous oxide by soil micro-organisms.<ref>{{Cite web |date=2021-12-13 |title=Reduce nitrous oxide emissions |url=https://www.agmatters.nz/goals/reduce-nitrous-oxide/ |access-date=2024-04-01 |website=Ag Matters |language=en}}</ref> As the third most important [[greenhouse gas]], nitrous oxide substantially contributes to [[global warming]].<ref name="ipccar5">{{cite book |url=https://www.ipcc.ch/report/ar5/wg1/ |contribution= Chapter 8 |title=AR5 Climate Change 2013: The Physical Science Basis |pages=677–678}}</ref><ref name="physorg">{{cite news |title=Nitrous oxide emissions pose an increasing climate threat, study finds |language=en |work=phys.org |url=https://phys.org/news/2020-10-nitrous-oxide-emissions-pose-climate.html |access-date=2020-11-09}}</ref> Reduction of emissions is an important goal in the [[politics of climate change]].<ref>{{Cite web |last=Mundschenk |first=Susanne |date=3 August 2022 |title=The Netherlands is showing how not to tackle climate change {{!}} The Spectator |url=https://www.spectator.co.uk/article/the-netherlands-is-showing-how-not-to-tackle-climate-change |access-date=2022-08-28 |website=www.spectator.co.uk |language=en}}</ref>