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, IR Spectrum, Mass spectrum (electron ionization), 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 | 0.05981 | atm | N/A | Fonseca and Lobo, 1989 | Uncertainty assigned by TRC = 0.00005 atm; 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 | 111.52 | atm | N/A | Brunner, 1988 | Uncertainty assigned by TRC = 0.05 atm; TRC |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
5.43 | 308. | N/A | Zander and Thomas, 1979 | Based on data from 293. to 392. K.; AC |
5.62 | 239. | N/A | Overstreet and Giauque, 1937 | Based on data from 199. to 241. K.; AC |
5.59 | 239. | C | Overstreet and Giauque, 1937 | 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 |
---|---|---|---|---|---|
164.0 to 239.6 | 3.18186 | 506.713 | -80.78 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
239.6 to 371.5 | 4.86315 | 1113.928 | -10.409 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
Enthalpy of sublimation
ΔsubH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
7.46 | 177. to 195. | Overstreet and Giauque, 1937 | AC |
IR Spectrum
Go To: Top, Phase change data, Mass spectrum (electron ionization), References, Notes
Data compiled by: Coblentz Society, Inc.
Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Mass spectrum (electron ionization)
Go To: Top, Phase change data, IR Spectrum, 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
Spectrum
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Additional Data
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Due to licensing restrictions, this spectrum cannot be downloaded.
Owner | NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
NIST MS number | 6 |
References
Go To: Top, Phase change data, IR Spectrum, Mass spectrum (electron ionization), 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]
Notes
Go To: Top, Phase change data, IR Spectrum, Mass spectrum (electron ionization), References
- Symbols used in this document:
Pc Critical pressure Ptriple Triple point pressure Tc Critical temperature Tfus Fusion (melting) point ΔsubH Enthalpy of sublimation ΔvapH Enthalpy of vaporization - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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