Nitrous oxide

Formula: N₂O
Molecular weight: 44.0128
IUPAC Standard InChI: InChI=1S/N2O/c1-2-3
IUPAC Standard InChIKey: GQPLMRYTRLFLPF-UHFFFAOYSA-N
CAS Registry Number: 10024-97-2
Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript.
Other names: Nitrogen oxide (N2O); Dinitrogen monoxide; Dinitrogen oxide; Laughing gas; N2O; Factitious air; Hyponitrous acid anhydride; Nitrogen oxide; UN 1070; UN 2201; Nitrogen monoxide; Nitral
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Information on this page:
Other data available:
- Gas phase thermochemistry data
- Reaction thermochemistry data: reactions 1 to 50, reactions 51 to 83
- Henry's Law data
- Ion clustering data
- IR Spectrum
- Mass spectrum (electron ionization)
- Fluid Properties
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NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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Phase change data

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Data compiled as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos

Quantity	Value	Units	Method	Reference	Comment
P_triple	0.86741	atm	N/A	Fonseca and Lobo, 1989	Uncertainty assigned by TRC = 0.0001 atm; TRC
P_triple	0.8676	atm	N/A	Calado, Rebelo, et al., 1986	Uncertainty assigned by TRC = 0.00008 atm; TRC
Quantity	Value	Units	Method	Reference	Comment
T_c	309.56	K	N/A	Ohgaki, Umezono, et al., 1990	Uncertainty assigned by TRC = 0.15 K; TRC
T_c	309.65	K	N/A	Li and Kiran, 1988	Uncertainty assigned by TRC = 0.2 K; TRC
T_c	309.49	K	N/A	Tsiklis and Prokhorov, 1967	TRC
T_c	309.55	K	N/A	Cook, 1953	Uncertainty assigned by TRC = 0.5 K; TRC
Quantity	Value	Units	Method	Reference	Comment
P_c	71.43	atm	N/A	Ohgaki, Umezono, et al., 1990	Uncertainty assigned by TRC = 0.20 atm; TRC
P_c	71.75	atm	N/A	Li and Kiran, 1988	Uncertainty assigned by TRC = 0.49 atm; TRC
P_c	71.400	atm	N/A	Cook, 1953	Uncertainty assigned by TRC = 0.5000 atm; TRC
Quantity	Value	Units	Method	Reference	Comment
V_c	0.0955	l/mol	N/A	Li and Kiran, 1988	Uncertainty assigned by TRC = 0.002 l/mol; TRC
Quantity	Value	Units	Method	Reference	Comment
ρ_c	10.3	mol/l	N/A	Ohgaki, Umezono, et al., 1990	Uncertainty assigned by TRC = 0.1 mol/l; TRC
ρ_c	10.2	mol/l	N/A	Tsiklis and Prokhorov, 1967	Visual in pVT apparatus, Khodeeva and Lebedeva Russ. J. Phys. Chem. 1966, 40, 1668.; TRC
ρ_c	10.3	mol/l	N/A	Cook, 1953	Uncertainty assigned by TRC = 0.05 mol/l; TRC

Enthalpy of vaporization

Δ_vapH (kcal/mol)	Temperature (K)	Reference	Comment
3.94	184.7	Atake and Chihara, 1974	AC
3.85	221.	Hoge, 1945	Based on data from 182. to 236. K.; AC

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
P = vapor pressure (atm)
T = temperature (K)

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Temperature (K)	A	B	C	Reference	Comment
129.8 to 187.7	4.37228	621.077	-44.659	Stull, 1947	Coefficents calculated by NIST from author's data.

Enthalpy of sublimation

Δ_subH (kcal/mol)	Temperature (K)	Method	Reference	Comment
6.00 ± 0.1	74.	LE	Bryson, Cazcarra, et al., 1974	Based on data from 68. to 80. K.; AC
5.88	161.	N/A	Blue and Giauque, 1935	Based on data from 148. to 182. K.; AC
5.64	113.	MG	Black, van Praagh, et al., 1930	Based on data from 103. to 123. K.; AC

Enthalpy of fusion

Δ_fusH (kcal/mol)	Temperature (K)	Reference	Comment
1.6	182.4	Atake and Chihara, 1974	AC

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:

Gas phase ion energetics data

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Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
B - John E. Bartmess

View reactions leading to N₂O⁺ (ion structure unspecified)

Quantity	Value	Units	Method	Reference	Comment
IE (evaluated)	12.889 ± 0.004	eV	N/A	N/A	L
Quantity	Value	Units	Method	Reference	Comment
Proton affinity (review)	131.4	kcal/mol	N/A	Hunter and Lias, 1998	at N; HL
Proton affinity (review)	137.5	kcal/mol	N/A	Hunter and Lias, 1998	at O; HL
Quantity	Value	Units	Method	Reference	Comment
Gas basicity	125.1	kcal/mol	N/A	Hunter and Lias, 1998	at N; HL
Gas basicity	131.1	kcal/mol	N/A	Hunter and Lias, 1998	at O; HL

Electron affinity determinations

EA (eV)	Method	Reference	Comment
0.22 ± 0.10	CIDT	Tiernan and Wu, 1978	B
>-0.15 ± 0.10	NBIE	Nalley, Compton, et al., 1973	B
0.27 ± 0.17	ECD	Wentworth, Chen, et al., 1971	B
<0.76 ± 0.10	LPES	Coe, Snodgrass, et al., 1986	Vertical Detachment Energy: ca. 1.5 eV. Anion bent, with little Franck-Condon overlap; B

Ionization energy determinations

IE (eV)	Method	Reference	Comment
12.89	PE	Kimura, Katsumata, et al., 1981	LLK
12. ± 1.	PI	Hitchcock, Brion, et al., 1980	LLK
12.91 ± 0.03	EI	Sahini, Constantin, et al., 1978	LLK
12.886 ± 0.002	PE	Berkowitz and Eland, 1977	LLK
12.88 ± 0.005	PI	Coppens, Smets, et al., 1974	LLK
12.89 ± 0.005	PI	Coppens, Smets, et al., 1974	LLK
12.90	PE	Eland, 1973	LLK
12.891 ± 0.008	PE	Collin and Natalis, 1969	RDSH
12.893 ± 0.005	PE	Brundle and Turner, 1969	RDSH
12.89	PI	Cook, Metzger, et al., 1968	RDSH
12.888 ± 0.007	PI	Dibeler and Walker, 1967	RDSH
12.8 ± 0.05	EI	Carette, 1967	RDSH
12.882 ± 0.008	PI	Nicholson, 1965	RDSH
12.894	S	Tanaka, Jursa, et al., 1960	RDSH
12.89	PE	Potts and Williams, 1974	Vertical value; LLK

Appearance energy determinations

Ion	AE (eV)	Other Products	Method	Reference	Comment
N⁺	20. ± 1.	NO	PI	Hitchcock, Brion, et al., 1980	LLK
N⁺	19.494	NO	PE	Berkowitz and Eland, 1977	LLK
N⁺	20.06	NO	PE	Dibeler, Walker, et al., 1967	RDSH
NO⁺	15.3 ± 0.1	N	EI	Olivier, Locht, et al., 1982	LBLHLM
NO⁺	16. ± 1.	N	PI	Hitchcock, Brion, et al., 1980	LLK
NO⁺	16.53 ± 0.01	N	PI	Coppens, Smets, et al., 1974	LLK
NO⁺	15.01	N	PI	Coppens, Smets, et al., 1974	LLK
NO⁺	17.73 ± 0.01	N	PI	Coppens, Smets, et al., 1974	LLK
NO⁺	14.3 ± 0.3	N(4Sø)	EI	Coleman, Delderfield, et al., 1969	RDSH
NO⁺	17.74	N(2Pø)?	PI	Dibeler and Walker, 1967	RDSH
NO⁺	16.53	N(2Dø)?	PI	Dibeler and Walker, 1967	RDSH
NO⁺	15.01	N(4Sø)	PI	Dibeler and Walker, 1967	RDSH
NO⁺	13.75 ± 0.10	N(4Sø)	EI	Curran and Fox, 1961	RDSH
N₂⁺	17.3 ± 0.2	O	EI	Olivier, Locht, et al., 1982	LBLHLM
N₂⁺	18. ± 1.	O	PI	Hitchcock, Brion, et al., 1980	LLK
N₂⁺	17.29	O	PI	Dibeler, 1967	RDSH
O⁺	15. ± 1.	N₂	PI	Hitchcock, Brion, et al., 1980	LLK
O⁺	15.31	N₂	PI	Dibeler, Walker, et al., 1967	RDSH

Gas Chromatography

Go To: Top, Phase change data, Gas phase ion energetics data, References, Notes

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Normal alkane RI, non-polar column, custom temperature program

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Column type	Active phase	I	Reference	Comment
Capillary	SPB-1	182.	Flanagan, Streete, et al., 1997	60. m/0.53 mm/5. μm, He; Program: 40C(6min) => 5C/min => 80C => 10C/min => 200C
Capillary	SPB-1	182.	Strete, Ruprah, et al., 1992	60. m/0.53 mm/5.0 μm, Helium; Program: 40 0C (6 min) 5 0C/min -> 80 0C 10 0C/min -> 200 0C

References

Go To: Top, Phase change data, Gas phase ion energetics data, Gas Chromatography, Notes

Fonseca and Lobo, 1989
Fonseca, I.M.A.; Lobo, L.Q., Thermodynamics of liquid mixtures of xenon and methyl fluoride, Fluid Phase Equilib., 1989, 47, 249. [all data]

Calado, Rebelo, et al., 1986
Calado, J.C.G.; Rebelo, L.P.N.; Streett, W.B.; Zollweg, J.A., Thermodynamics of liquid (dimethylether + xenon), J. Chem. Thermodyn., 1986, 18, 931. [all data]

Ohgaki, Umezono, et al., 1990
Ohgaki, K.; Umezono, S.; Katayama, T., Pressure-density-temperature (p-ρ-T) relations of fluoroform, nitrous oxide, and propene in the critical region, J. Supercrit. Fluids, 1990, 3, 78-84. [all data]

Li and Kiran, 1988
Li, L.; Kiran, E., Gas-Liquid Critical Properties of Methylamine + Nitrous Oxide and Methylamine + Ethylene Binary Mixtures, J. Chem. Eng. Data, 1988, 33, 342. [all data]

Tsiklis and Prokhorov, 1967
Tsiklis, D.S.; Prokhorov, V.M., Phase equilibria in systems containing fluorine compounds, Zh. Fiz. Khim., 1967, 41, 2195-9. [all data]

Cook, 1953
Cook, D., Vapor Pressure and Orthobaric Density of Nitrous Oxide, Trans. Faraday Soc., 1953, 49, 716. [all data]

Atake and Chihara, 1974
Atake, Tooru; Chihara, Hideaki, A New Condensed Gas Calorimeter. Thermodynamic Properties of Solid and Liquid Dinitrogen Oxide, Bull. Chem. Soc. Jpn., 1974, 47, 9, 2126-2136, https://doi.org/10.1246/bcsj.47.2126 . [all data]

Hoge, 1945
Hoge, H.J., Vapor pressure, latent heat of vaporization, and triple-point temperature of N2O, J. RES. NATL. BUR. STAN., 1945, 34, 3, 281-17, https://doi.org/10.6028/jres.034.015 . [all data]

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [all data]

Bryson, Cazcarra, et al., 1974
Bryson, Charles E.; Cazcarra, Victor; Levenson, Leonard L., Sublimation rates and vapor pressures of water, carbon dioxide, nitrous oxide, and xenon, J. Chem. Eng. Data, 1974, 19, 2, 107-110, https://doi.org/10.1021/je60061a021 . [all data]

Blue and Giauque, 1935
Blue, R.W.; Giauque, W.F., The Heat Capacity and Vapor Pressure of Solid and Liquid Nitrous Oxide. The Entropy from its Band Spectrum, J. Am. Chem. Soc., 1935, 57, 6, 991-997, https://doi.org/10.1021/ja01309a008 . [all data]

Black, van Praagh, et al., 1930
Black, H.K.; van Praagh, G.; Topley, B., Note on the vapour pressure of solid nitrous oxide, Trans. Faraday Soc., 1930, 26, 196, https://doi.org/10.1039/tf9302600196 . [all data]

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Tiernan and Wu, 1978
Tiernan, T.O.; Wu, R.L.C., Thermochemical Data for Molecular Negative Ions from Collisional Dissociation Thresholds, Adv. Mass Spectrom., 1978, 7A, 136. [all data]

Nalley, Compton, et al., 1973
Nalley, S.J.; Compton, R.N.; Schweinler, H.C.; Anderson, V.E., Molecular electron affinities from collisional ionization of cesium. I. NO, NO₂, and N₂O, J. Chem. Phys., 1973, 59, 4125. [all data]

Wentworth, Chen, et al., 1971
Wentworth, W.E.; Chen, E.; Freeman, R., Thermal electron attachment to N₂O, J. Chem. Phys., 1971, 55, 2075. [all data]

Coe, Snodgrass, et al., 1986
Coe, J.V.; Snodgrass, J.T.; Freidhoff, C.B.; McHugh, K.M.; Bowen, K.H., Negative ion photoelectron spectroscopy of N₂O^- and (N₂O)₂^-, Chem. Phys. Lett., 1986, 124, 274. [all data]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Hitchcock, Brion, et al., 1980
Hitchcock, A.P.; Brion, C.E.; Van der Wiel, M.J., Absolute oscillator strengths for valence-shell ionic photofragmentation of N₂O and CO₂(8-75 eV), Chem. Phys., 1980, 45, 461. [all data]

Sahini, Constantin, et al., 1978
Sahini, V.E.; Constantin, V.; Serban, I., Determination of ionization potentials using a MI-1305 mass spectrometer, Rev. Roum. Chim., 1978, 23, 479. [all data]

Berkowitz and Eland, 1977
Berkowitz, J.; Eland, J.H.D., Photoionization of N₂O: Mechanisms of photoionization and ion dissociation, J. Chem. Phys., 1977, 67, 2740. [all data]

Coppens, Smets, et al., 1974
Coppens, P.; Smets, J.; Fishel, M.G.; Drowart, J., Mass spectrometric study of the photoionization of nitrous oxide in the wavelength interval 1000-600 A, Int. J. Mass Spectrom. Ion Phys., 1974, 14, 57. [all data]

Eland, 1973
Eland, J.H.D., Predissociation of N₂O⁺ and COS⁺ ions studied by photoelectronphotoion coincidence spectroscopy, Int. J. Mass Spectrom. Ion Phys., 1973, 12, 389. [all data]

Collin and Natalis, 1969
Collin, J.E.; Natalis, P., Determination des etats electroniques et des niveaux de vibration des ions moleculaires par spectroscopie de photoelectrons, Bull. Classe Sci. Acad. Roy. Belg., 1969, 55, 352. [all data]

Brundle and Turner, 1969
Brundle, C.R.; Turner, D.W., Studies on the photoionisation of the linear triatomic molecules: N₂O, COS, CS₂ and CO₂ using high-resolution photoelectron spectroscopy, Intern. J. Mass Spectrom. Ion Phys., 1969, 2, 195. [all data]

Cook, Metzger, et al., 1968
Cook, G.R.; Metzger, P.H.; Ogawa, M., Photoionization and absorption coefficients of N₂O, J. Opt. Soc. Am., 1968, 58, 129. [all data]

Dibeler and Walker, 1967
Dibeler, V.H.; Walker, J.A., Mass spectrometric study of the photoionization of small polyatomic molecules, Advan. Mass Spectrom., 1967, 4, 767. [all data]

Carette, 1967
Carette, J.-D., Ionisation par impact electronique de CO₂ et N₂O, Can. J. Phys., 1967, 45, 2931. [all data]

Nicholson, 1965
Nicholson, A.J.C., Photoionization-efficiency curves. II. False and genuine structure, J. Chem. Phys., 1965, 43, 1171. [all data]

Tanaka, Jursa, et al., 1960
Tanaka, Y.; Jursa, A.S.; LeBlanc, F.J., Higher ionization potentials of linear triatomic molecules. II. CS₂, COS, and N₂O, J. Chem. Phys., 1960, 32, 1205. [all data]

Potts and Williams, 1974
Potts, A.W.; Williams, T.A., The observation of "forbidden" transitions in He II photoelectron spectra, J. Electron Spectrosc. Relat. Phenom., 1974, 3, 3. [all data]

Dibeler, Walker, et al., 1967
Dibeler, V.H.; Walker, J.A.; Liston, S.K., Mass spectrometric study of photoionization. VII.Nitrogen dioxide and nitrous oxide, J.Res. NBS, 1967, 71A, 371. [all data]

Olivier, Locht, et al., 1982
Olivier, J.L.; Locht, R.; Momigny, J., A dissociative electroionization study of nitrous oxide. The No and N₂ dissociation channels, Chem. Phys., 1982, 68, 201. [all data]

Coleman, Delderfield, et al., 1969
Coleman, R.J.; Delderfield, J.S.; Reuben, B.G., The gas-phase decomposition of the nitrous oxide ion, Intern. J. Mass Spectrom. Ion Phys., 1969, 2, 25. [all data]

Curran and Fox, 1961
Curran, R.K.; Fox, R.E., Mass spectrometer investigation of ionization of N₂O by electron impact, J. Chem. Phys., 1961, 34, 1590. [all data]

Dibeler, 1967
Dibeler, V.H., N₂O bond dissociation energy by photon impact, J. Chem. Phys., 1967, 47, 2191. [all data]

Flanagan, Streete, et al., 1997
Flanagan, R.J.; Streete, P.J.; Ramsey, J.D., Volatile Substance Abuse, UNODC Technical Series, No 5, United Nations, Office on Drugs and Crime, Vienna International Centre, PO Box 500, A-1400 Vienna, Austria, 1997, 56, retrieved from http://www.odccp.org/pdf/technical_series₁997-01-01₁.pdf. [all data]

Strete, Ruprah, et al., 1992
Strete, P.J.; Ruprah, M.; Ramsey, J.D.; Flanagan, R.J., Detection and identification of volatile substances by headspace capillary gas chromatography to aid the diagnosis of acute poisoning, Analyst, 1992, 117, 7, 1111-1127, https://doi.org/10.1039/an9921701111 . [all data]

Notes

Go To: Top, Phase change data, Gas phase ion energetics data, Gas Chromatography, References

Symbols used in this document:

AE	Appearance energy
EA	Electron affinity
IE (evaluated)	Recommended ionization energy
P_c	Critical pressure
P_triple	Triple point pressure
T_c	Critical temperature
V_c	Critical volume
Δ_fusH	Enthalpy of fusion
Δ_subH	Enthalpy of sublimation
Δ_vapH	Enthalpy of vaporization
ρ_c	Critical density

Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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