Ammonia

• Formula: H₃N
• Molecular weight: 17.0305
• IUPAC Standard InChI: InChI=1S/H3N/h1H3 Copy

  
• IUPAC Standard InChIKey: QGZKDVFQNNGYKY-UHFFFAOYSA-N Copy
• 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:
  • Ammonia-d3
• Other names: Ammonia gas; Nitro-Sil; Spirit of Hartshorn; NH3; Ammonia, anhydrous; Anhydrous ammonia; Aromatic Ammonia, Vaporole
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data (reactions 1 to 50)
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data: reactions 51 to 100, reactions 101 to 146
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
  • Gas Chromatography
  • Fluid Properties
• Data at other public NIST sites:
  • Electron-Impact Ionization Cross Sections (on physics web site)
  • Computational Chemistry Comparison and Benchmark Database
  • Gas Phase Kinetics Database
  • X-ray Photoelectron Spectroscopy Database, version 5.0
• Options:
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Gas phase thermochemistry data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Gas Phase Heat Capacity (Shomate Equation)

C_p° = A + B*t + C*t² + D*t³ + E/t²
H° − H°_298.15= A*t + B*t²/2 + C*t³/3 + D*t⁴/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t²/2 + D*t³/3 − E/(2*t²) + G
    C_p = heat capacity (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

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Phase change data

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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

Enthalpy of vaporization

Antoine Equation Parameters

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

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Enthalpy of sublimation

Reaction thermochemistry data

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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:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
B - John E. Bartmess
RCD - Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Reactions 1 to 50

( • 3) +  = ( • 4)

By formula: (H₄N⁺ • 3H₃N) + H₃N = (H₄N⁺ • 4H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Free energy of reaction

( • 2) +  = ( • 3)

By formula: (H₄N⁺ • 2H₃N) + H₃N = (H₄N⁺ • 3H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Free energy of reaction

( • ) +  = ( • 2)

By formula: (H₄N⁺ • H₃N) + H₃N = (H₄N⁺ • 2H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Free energy of reaction

 +  = ( • )

By formula: H₄N⁺ + H₃N = (H₄N⁺ • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Free energy of reaction

 +  = ( • )

By formula: Cl^- + H₃N = (Cl^- • H₃N)

Bond type: Hydrogen bond (negative ion to hydride)

( • 4) +  = ( • 5)

By formula: (H₄N⁺ • 4H₃N) + H₃N = (H₄N⁺ • 5H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

 +  = ( • )

By formula: Li⁺ + H₃N = (Li⁺ • H₃N)

( • ) +  = ( • 2)

By formula: (Na⁺ • H₃N) + H₃N = (Na⁺ • 2H₃N)

H₂N^- +  =

By formula: H₂N^- + H⁺ = H₃N

C₄H₉⁺ +  = (C₄H₉⁺ • )

By formula: C₄H₉⁺ + H₃N = (C₄H₉⁺ • H₃N)

 +  = ( • )

By formula: Na⁺ + H₃N = (Na⁺ • H₃N)

Free energy of reaction

C₃H₉Sn⁺ +  = (C₃H₉Sn⁺ • )

By formula: C₃H₉Sn⁺ + H₃N = (C₃H₉Sn⁺ • H₃N)

Free energy of reaction

( • 3 • ) +  = ( • 4 • )

By formula: (H₄N⁺ • 3CHN • H₃N) + CHN = (H₄N⁺ • 4CHN • H₃N)

Free energy of reaction

 +  = ( • )

By formula: I^- + H₃N = (I^- • H₃N)

Bond type: Hydrogen bond (negative ion to hydride)

( •  • 2) +  = ( • 2 • 2)

By formula: (H₄N⁺ • H₃N • 2CHN) + H₃N = (H₄N⁺ • 2H₃N • 2CHN)

Free energy of reaction

( •  • 2) +  = ( • 2 • 2)

By formula: (H₄N⁺ • CHN • 2H₃N) + CHN = (H₄N⁺ • 2CHN • 2H₃N)

Free energy of reaction

( • ) +  = ( •  • )

By formula: (H₄N⁺ • CHN) + H₃N = (H₄N⁺ • H₃N • CHN)

Free energy of reaction

 +  = ( • )

By formula: Br^- + H₃N = (Br^- • H₃N)

Bond type: Hydrogen bond (negative ion to hydride)

( • 5) +  = ( • 6)

By formula: (H₄N⁺ • 5H₃N) + H₃N = (H₄N⁺ • 6H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

 +  = ( • )

By formula: K⁺ + H₃N = (K⁺ • H₃N)

( • 2) +  = ( •  • 2)

By formula: (H₄N⁺ • 2H₃N) + CHN = (H₄N⁺ • CHN • 2H₃N)

( •  • 2) +  = ( • 2 • 2)

By formula: (H₄N⁺ • H₃N • 2H₂O) + H₃N = (H₄N⁺ • 2H₃N • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( •  • 2) +  = ( • 2 • 2)

By formula: (H₄N⁺ • H₂O • 2H₃N) + H₂O = (H₄N⁺ • 2H₂O • 2H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

(C₆H₁₅O₃⁺ • ) +  = (C₆H₁₅O₃⁺ •  • )

By formula: (C₆H₁₅O₃⁺ • H₃N) + C₆H₁₄O₃ = (C₆H₁₅O₃⁺ • C₆H₁₄O₃ • H₃N)

Bond type: Hydrogen bonds between protonated and neutral organics

( • 2 • ) +  = ( • 3 • )

By formula: (H₄N⁺ • 2H₃N • H₂O) + H₃N = (H₄N⁺ • 3H₃N • H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 2 • ) +  = ( • 3 • )

By formula: (H₄N⁺ • 2H₂O • H₃N) + H₂O = (H₄N⁺ • 3H₂O • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

( •  • ) +  = ( • 2 • )

By formula: (H₄N⁺ • H₃N • H₂O) + H₃N = (H₄N⁺ • 2H₃N • H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( •  • ) +  = ( • 2 • )

By formula: (H₄N⁺ • H₂O • H₃N) + H₂O = (H₄N⁺ • 2H₂O • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

( • 2) +  = ( •  • 2)

By formula: (H₄N⁺ • 2H₃N) + H₂O = (H₄N⁺ • H₂O • 2H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

( • 2) +  = ( •  • 2)

By formula: (H₄N⁺ • 2H₂O) + H₃N = (H₄N⁺ • H₃N • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 3) +  = ( •  • 3)

By formula: (H₄N⁺ • 3H₃N) + H₂O = (H₄N⁺ • H₂O • 3H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

( • 3) +  = ( •  • 3)

By formula: (H₄N⁺ • 3H₂O) + H₃N = (H₄N⁺ • H₃N • 3H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • ) +  = ( •  • )

By formula: (H₄N⁺ • H₃N) + H₂O = (H₄N⁺ • H₂O • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

( • ) +  = ( •  • )

By formula: (H₄N⁺ • H₂O) + H₃N = (H₄N⁺ • H₃N • H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • ) +  = ( •  • )

By formula: (H₄N⁺ • C₄H₁₀O₂) + H₃N = (H₄N⁺ • H₃N • C₄H₁₀O₂)

Bond type: Hydrogen bond (positive ion to hydride)

 +  = ( • )

By formula: H^- + H₃N = (H^- • H₃N)

( • 2) +  = ( • 3)

By formula: (Cu⁺ • 2H₃N) + H₃N = (Cu⁺ • 3H₃N)

( • 3) +  = ( • 4)

By formula: (Cu⁺ • 3H₃N) + H₃N = (Cu⁺ • 4H₃N)

( • 2) +  = ( • 3)

By formula: (Pb⁺ • 2H₃N) + H₃N = (Pb⁺ • 3H₃N)

( • 3) +  = ( • 4)

By formula: (Pb⁺ • 3H₃N) + H₃N = (Pb⁺ • 4H₃N)

( • ) +  = ( • 2)

By formula: (Pb⁺ • H₃N) + H₃N = (Pb⁺ • 2H₃N)

C₂H₈N⁺ +  = (C₂H₈N⁺ • )

By formula: C₂H₈N⁺ + H₃N = (C₂H₈N⁺ • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

C₆H₁₅O₃⁺ +  = (C₆H₁₅O₃⁺ • )

By formula: C₆H₁₅O₃⁺ + H₃N = (C₆H₁₅O₃⁺ • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

CH₆N⁺ +  = (CH₆N⁺ • )

By formula: CH₆N⁺ + H₃N = (CH₆N⁺ • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

 +  = ( • )

By formula: Pb⁺ + H₃N = (Pb⁺ • H₃N)

( • ) +  = ( • 2)

By formula: (H^- • H₃N) + H₃N = (H^- • 2H₃N)

(H₂N^- • ) +  = (H₂N^- • 2)

By formula: (H₂N^- • H₃N) + H₃N = (H₂N^- • 2H₃N)

( • 2 • ) +  = ( • 3 • )

By formula: (H₄N⁺ • 2CHN • H₃N) + CHN = (H₄N⁺ • 3CHN • H₃N)

( •  • ) +  = ( • 2 • )

By formula: (H₄N⁺ • CHN • H₃N) + CHN = (H₄N⁺ • 2CHN • H₃N)

( • 2 • ) +  = ( • 3 • )

By formula: (H₄N⁺ • 2H₃N • C₂H₃N) + H₃N = (H₄N⁺ • 3H₃N • C₂H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• GAS (50 mmHg DILUTED TO A TOTAL PRESSURE OF 600 mmHg WITH N2); DOW KBr FOREPRISM; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm^-1 resolution

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

• gas

Mass spectrum (electron ionization)

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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

Vibrational and/or electronic energy levels

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Takehiko Shimanouchi

Symmetry:   C_3ν     Symmetry Number σ = 3

Source: Shimanouchi, 1972

Notes

References

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), Vibrational and/or electronic energy levels, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Cox, Wagman, et al., 1984
Cox, J.D.; Wagman, D.D.; Medvedev, V.A., CODATA Key Values for Thermodynamics, Hemisphere Publishing Corp., New York, 1984, 1. [all data]

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Timmermans, J., The Freezing Points of Organic Substances IV. New Exp. Determinations, Bull. Soc. Chim. Belg., 1921, 30, 62. [all data]

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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]

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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]

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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]

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Fehsenfeld, F.C.; Ferguson, E.E., Thermal Energy Positive Ion Reactions in a Wet Atmosphere Containing Ammonia, J. Chem. Phys., 1973, 59, 12, 6272, https://doi.org/10.1063/1.1680006 . [all data]

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Puckett, L.J.; Teague, M.W., Ion-Molecule Reactions in NO - NH3 Gas Mixtures, J. Chem. Phys., 1971, 54, 11, 4860, https://doi.org/10.1063/1.1674763 . [all data]

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Arshadi and Futrell, 1974
Arshadi, M.R.; Futrell, J.H., Studies in High - Pressure Mass Spectrometry. V. Thermodynamics of Solvation Reactions. NH4+ - NH3, J. Phys. Chem., 1974, 78, 15, 1482, https://doi.org/10.1021/j100608a008 . [all data]

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Searles and Kebarle, 1968
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Payzant, Cunningham, et al., 1973
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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]

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Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), Vibrational and/or electronic energy levels, References

• Symbols used in this document:
  

  Pc	Critical pressure
  Ptriple	Triple point pressure
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  T	Temperature
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy 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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