Ammonia
- Formula: H3N
- Molecular weight: 17.0305
- IUPAC Standard InChIKey: QGZKDVFQNNGYKY-UHFFFAOYSA-N
- CAS Registry Number: 7664-41-7
- 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. - Isotopologues:
- Other names: Ammonia gas; Nitro-Sil; Spirit of Hartshorn; NH3; Ammonia, anhydrous; Anhydrous ammonia; Aromatic Ammonia, Vaporole
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Phase change data
Go To: Top, Gas phase ion energetics data, Gas Chromatography, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
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 |
---|---|---|---|---|---|
Tfus | 194.95 | K | N/A | Timmermans, 1921 | Uncertainty assigned by TRC = 0.3 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ptriple | 0.06060 | bar | N/A | Fonseca and Lobo, 1989 | Uncertainty assigned by TRC = 0.00005 bar; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 405.4 | K | N/A | Brunner, 1988 | Uncertainty assigned by TRC = 0.1 K; TRC |
Tc | 405.6 | K | N/A | Hentze, 1977 | Uncertainty assigned by TRC = 5. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 113.00 | bar | N/A | Brunner, 1988 | Uncertainty assigned by TRC = 0.05 bar; TRC |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
22.7 | 308. | N/A | Zander and Thomas, 1979 | Based on data from 293. to 392. K.; AC |
23.5 | 239. | N/A | Overstreet and Giauque, 1937 | Based on data from 199. to 241. K.; AC |
23.4 | 239. | C | Overstreet and Giauque, 1937 | AC |
Antoine Equation Parameters
log10(P) = A − (B / (T + C))
P = vapor pressure (bar)
T = temperature (K)
View plot Requires a JavaScript / HTML 5 canvas capable browser.
Temperature (K) | A | B | C | Reference | Comment |
---|---|---|---|---|---|
164.0 to 239.6 | 3.18757 | 506.713 | -80.78 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
239.6 to 371.5 | 4.86886 | 1113.928 | -10.409 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
Enthalpy of sublimation
ΔsubH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
31.2 | 177. to 195. | Overstreet and Giauque, 1937 | AC |
Gas phase ion energetics data
Go To: Top, Phase change data, Gas Chromatography, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias
Data compiled as indicated in comments:
B - John E. Bartmess
LL - Sharon G. Lias and Joel F. Liebman
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
View reactions leading to H3N+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 10.070 ± 0.020 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 853.6 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 819.0 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
H+ | 18.57 | H2N | PI | Qi, Sheng, et al., 1995 | LL |
HN+ | 28. ± 1.5 | H2/2H | EI | Muller and Schulz, 1990 | LL |
HN+ | 16.9 ± 0.1 | H2 | EI | Locht, Servais, et al., 1988 | LL |
HN+ | 17.2 | H2 | EI | Morrison and Traeger, 1973 | LLK |
NH+ | 17.1 ± 0.1 | H2 | EI | Reed and Snedden, 1959 | RDSH |
H2N+ | 15.75 | H | PI | Qi, Sheng, et al., 1995 | LL |
H2N+ | 15.60 ± 0.02 | H | PIPECO | Ruede, Troxler, et al., 1993 | LL |
H2N+ | 15.75 | H | PI | Locht, Hottmann, et al., 1992 | LL |
H2N+ | 15.76 ± 0.05 | H | PI | Locht, Servais, et al., 1988 | LL |
H2N+ | 15.76 ± 0.05 | H | EI | Locht, Servais, et al., 1988 | LL |
H2N+ | 15.5 | H | PIPECO | Powis, 1981 | LLK |
H2N+ | 15.87 ± 0.13 | H | DER | Powis, 1981 | LLK |
H2N+ | 15.768 ± 0.004 | H | PI | McCulloh, 1976 | LLK |
H2N+ | 15.0 | H | EI | Morrison and Traeger, 1973 | LLK |
NH2+ | 15.73 ± 0.02 | H | PI | Dibeler, Walker, et al., 1966 | RDSH |
NH2+ | 16.0 ± 0.1 | H | EI | Foner and Hudson, 1958 | RDSH |
N+ | ≤22.5 | H2+H | EI | Morrison and Traeger, 1973 | LLK |
N+ | 22.6 ± 0.1 | H2+H | EI | Reed and Snedden, 1959 | RDSH |
De-protonation reactions
H2N- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1688.0 ± 1.2 | kJ/mol | D-EA | Wickham-Jones, Ervin, et al., 1989 | gas phase; B |
ΔrH° | 1688.5 ± 3.3 | kJ/mol | G+TS | MacKay, Hemsworth, et al., 1976 | gas phase; B |
ΔrH° | 1683.2 | kJ/mol | N/A | Check, Faust, et al., 2001 | gas phase; HCrO3(t); ; ΔS(EA)=6.6; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1656.8 ± 1.6 | kJ/mol | H-TS | Wickham-Jones, Ervin, et al., 1989 | gas phase; B |
ΔrG° | 1657.3 ± 2.9 | kJ/mol | IMRE | MacKay, Hemsworth, et al., 1976 | gas phase; B |
ΔrG° | 1654.4 | kJ/mol | N/A | Check, Faust, et al., 2001 | gas phase; HCrO3(t); ; ΔS(EA)=6.6; B |
Gas Chromatography
Go To: Top, Phase change data, Gas phase ion energetics data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Kovats' RI, non-polar column, isothermal
Column type | Active phase | Temperature (C) | I | Reference | Comment |
---|---|---|---|---|---|
Packed | PMS-100 | 150. | 118. | Anderson, Jurel, et al., 1973 | He, Celite 545 (44-60 mesh); Column length: 3. m |
Packed | PMS-100 | 180. | 131. | Anderson, Jurel, et al., 1973 | He, Celite 545 (44-60 mesh); Column length: 3. m |
References
Go To: Top, Phase change data, Gas phase ion energetics data, Gas Chromatography, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Timmermans, 1921
Timmermans, J.,
The Freezing Points of Organic Substances IV. New Exp. Determinations,
Bull. Soc. Chim. Belg., 1921, 30, 62. [all data]
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]
Brunner, 1988
Brunner, E.,
Fluid Mixtures at High Pressures VI. Phase Separation and Critical Phenomena in 18 (n-Alkane + Ammonia) and 4 (n-Alkane _ Methanol) Mixtures,
J. Chem. Thermodyn., 1988, 20, 273. [all data]
Hentze, 1977
Hentze, G.,
Critical temperature measurement of liquids by means of differential thermal analysis,
Thermochim. Acta, 1977, 20, 27-30. [all data]
Zander and Thomas, 1979
Zander, Manfred; Thomas, Wilhelm,
Some thermodynamic properties of liquid ammonia: PVT data, vapor pressure, and critical temperature,
J. Chem. Eng. Data, 1979, 24, 1, 1-2, https://doi.org/10.1021/je60080a003
. [all data]
Overstreet and Giauque, 1937
Overstreet, Roy; Giauque, W.F.,
Ammonia. The Heat Capacity and Vapor Pressure of Solid and Liquid. Heat of Vaporization. The Entropy Values from Thermal and Spectroscopic Data,
J. Am. Chem. Soc., 1937, 59, 2, 254-259, https://doi.org/10.1021/ja01281a008
. [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]
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]
Qi, Sheng, et al., 1995
Qi, F.; Sheng, L.; Zhang, Y.; Yu, S.; Li, W.-K.,
Experimental and theoretical study of the dissociation energies DO(H2N-H) and DO(H2N+-H) and other related quantities,
Chem. Phys. Lett., 1995, 234, 450. [all data]
Ruede, Troxler, et al., 1993
Ruede, R.; Troxler, H.; Beglinger, C.; Jungen, M.,
The dissociation energies of the positive ions NH3+, NF3+, PH3+, PF3+ and PCl3+,
Chem. Phys. Lett., 1993, 203, 477. [all data]
Reiser, Habenicht, et al., 1993
Reiser, G.; Habenicht, W.; Muller-Dethlefs, K.,
Zero kinetic energy (ZEKE) photoelectron spectroscopy of ammonia by nonresonant two-photon ionization from the neutral ground state,
J. Chem. Phys., 1993, 98, 8462. [all data]
Locht, Hottmann, et al., 1992
Locht, R.; Hottmann, K.; Hagenow, G.; Denzer, W.; Baumgartel, H.,
The threhold-photoelectron spectrum of NH3,
Chem. Phys. Lett., 1992, 190, 124. [all data]
Locht, Leyh, et al., 1991
Locht, R.; Leyh, B.; Denzer, W.; Hagenow, G.; Baumgartel, H.,
The photoionization of ammonia revisited. The vibrational autoionization of NH3 and its three isotopomers in the 10-12 eV photon energy range,
Chem. Phys., 1991, 155, 407. [all data]
Habenicht, 1989
Habenicht, W.,
[Title unavailable], Ph.D. Thesis, Technische Universitat Munchen, 1989. [all data]
Baldwin, Loudon, et al., 1977
Baldwin, M.A.; Loudon, A.G.; Webb, K.S.; Cardnell, P.C.,
Charge location and fragmentation under electron impact. V-The ionization potentials of (methylated) phosphoramides, guanidines, formamides, acetamides, ureas and thioureas,
Org. Mass Spectrom., 1977, 12, 279. [all data]
Debies and Rabalais, 1975
Debies, T.P.; Rabalais, J.W.,
Calculated photoionization cross-sections and angular distributions for the isoelectronic series Ne, HF, H2O, NH3, and CH4,
J. Am. Chem. Soc., 1975, 97, 487. [all data]
Aue, Webb, et al., 1975
Aue, D.H.; Webb, H.M.; Bowers, M.T.,
Photoelectron spectrum and gas-phase basicity of manxine. Evidence for a planar bridgehead nitrogen,
J. Am. Chem. Soc., 1975, 97, 4136. [all data]
Morrison and Traeger, 1973
Morrison, J.D.; Traeger, J.C.,
Ionization and dissociation by electron impact. II. NH3 and PH3,
Int. J. Mass Spectrom. Ion Phys., 1973, 11, 277. [all data]
Potts and Price, 1972
Potts, A.W.; Price, W.C.,
Photoelectron spectra and valence shell orbital structures of groups V VI hydrides,
Proc. R. Soc. London A:, 1972, 326, 181. [all data]
Weiss and Lawrence, 1970
Weiss, M.J.; Lawrence, G.M.,
Photoelectron spectroscopy of NH3 and ND3 using molecular beams,
J. Chem. Phys., 1970, 53, 214. [all data]
Branton, Frost, et al., 1969
Branton, G.R.; Frost, D.C.; Herring, F.G.; McDowell, C.A.; Stenhouse, I.A.,
The ionization potentials of ammonia and ammonia-d3, measured by photoelectron spectroscopy, and an INDO calculation of these values,
Chem. Phys. Lett., 1969, 3, 581. [all data]
Potapov, 1968
Potapov, V.K.,
Mechanism of ionic-molecular reactions,
Dokl. Akad. Nauk SSSR, 1968, 183, 386, In original 843. [all data]
Chupka and Russell, 1968
Chupka, W.A.; Russell, M.E.,
Ion-molecule reactions of NH3+ by photoionization,
J. Chem. Phys., 1968, 48, 1527. [all data]
Dibeler, Walker, et al., 1966
Dibeler, V.H.; Walker, J.A.; Rosenstock, H.M.,
Mass spectrometric study of photoionization. V.Water and ammonia,
J.Res. NBS, 1966, 70A, 459. [all data]
Watanabe and Sood, 1965
Watanabe, K.; Sood, S.P.,
Absorption and photoionization coefficients of NH3 in the 580-1650 A region,
Sci. Light (Tokyo), 1965, 14, 36. [all data]
Al-Joboury and Turner, 1964
Al-Joboury, M.I.; Turner, D.W.,
Molecular photoelectron spectroscopy. Part II. A summary of ionization potentials,
J. Chem. Soc., 1964, 4434. [all data]
Watanabe and Mottl, 1957
Watanabe, K.; Mottl, J.R.,
Ionization potentials of ammonia and some amines,
J. Chem. Phys., 1957, 26, 1773. [all data]
Baumgartel, Jochims, et al., 1989
Baumgartel, H.; Jochims, H.-W.; Ruhl, E.; Bock, H.; Dammel, R.; Minkwitz, J.; Nass, R.,
Photoelectron and photoionization mass spectra of the fluoramines NH3-nFn1,
Inorg. Chem., 1989, 28, 943. [all data]
Bieri, Asbrink, et al., 1982
Bieri, G.; Asbrink, L.; Von Niessen, W.,
30.4-nm He(II) photoelectron spectra of organic molecules,
J. Electron Spectrosc. Relat. Phenom., 1982, 27, 129. [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]
Campbell, Liesegang, et al., 1979
Campbell, M.J.; Liesegang, J.; Riley, J.D.; Leckey, R.C.G.; Jenkin, J.G.; Poole, R.T.,
The electronic structure of the valence bands of solid NH3 and H2O studied by ultraviolet photoelectron spectroscopy,
J. Electron Spectrosc. Relat. Phenom., 1979, 15, 83. [all data]
Daamen and Oskam, 1978
Daamen, H.; Oskam, A.,
Bonding properties of some monosubstituted chromium and tungsten hexacarbonyls M(CO)5L (L=amine, substituted pyridine, azine),
Inorg. Chim. Acta, 1978, 26, 81. [all data]
Muller and Schulz, 1990
Muller, U.; Schulz, G.,
Electron-impact dissociation of ammonia; formation of NH+ ions in excited states,
Chem. Phys. Lett., 1990, 170, 401. [all data]
Locht, Servais, et al., 1988
Locht, R.; Servais, C.; Ligot, M.; Derwa, F.; Momigny, J.,
The dissociative electroionization of ammonia and ammonia-d3. I. The NH+ and NH2+ dissociation channels,
Chem. Phys., 1988, 123, 443. [all data]
Reed and Snedden, 1959
Reed, R.I.; Snedden, W.,
The ionisation potential of NH,
J. Chem. Soc., 1959, 4132. [all data]
Powis, 1981
Powis, I.,
Influence of angular momentum in the dissociation of NH3+,
J. Chem. Soc. Faraday Trans. 2, 1981, 77, 1433. [all data]
McCulloh, 1976
McCulloh, K.E.,
Energetics and mechanisms of fragment ion formation in the photoionization of normal and deuterated water and ammonia,
Int. J. Mass Spectrom. Ion Phys., 1976, 21, 333. [all data]
Foner and Hudson, 1958
Foner, S.N.; Hudson, R.L.,
Mass spectrometric detection of triazene and tetrazene and studies of the free radicals NH2, and N2H3,
J. Chem. Phys., 1958, 29, 442. [all data]
Wickham-Jones, Ervin, et al., 1989
Wickham-Jones, C.T.; Ervin, K.M.; Ellison, G.B.; Lineberger, W.C.,
NH2 Electron Affinity,
J. Chem. Phys., 1989, 91, 4, 2762, https://doi.org/10.1063/1.456994
. [all data]
MacKay, Hemsworth, et al., 1976
MacKay, G.J.; Hemsworth, R.S.; Bohme, D.K.,
Absolute gas-phase acidities of CH3NH2, C2H5NH2, (CH3)2NH, and (CH3)3N,
Can. J. Chem., 1976, 54, 1624. [all data]
Check, Faust, et al., 2001
Check, C.E.; Faust, T.O.; Bailey, J.M.; Wright, B.J.; Gilbert, T.M.; Sunderlin, L.S.,
Addition of Polarization and Diffuse Functions to the LANL2DZ Basis Set for P-Block Elements,
J. Phys. Chem. A,, 2001, 105, 34, 8111, https://doi.org/10.1021/jp011945l
. [all data]
Anderson, Jurel, et al., 1973
Anderson, A.; Jurel, S.; Shymanska, M.; Golender, L.,
Gas-liquid chromatography of some aliphatic and heterocyclic mono- and pollyfunctional amines. VII. Retention indices of amines in some polar and unpolar stationary phases,
Latv. PSR Zinat. Akad. Vestis Kim. Ser., 1973, 1, 51-63. [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 IE (evaluated) Recommended ionization energy Pc Critical pressure Ptriple Triple point pressure Tc Critical temperature Tfus Fusion (melting) point ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔsubH Enthalpy of sublimation ΔvapH Enthalpy of vaporization - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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