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
  View 3d structure (requires JavaScript / HTML 5)
• 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:
  • Phase change data
  • Reaction thermochemistry data (reactions 1 to 50)
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data: reactions 51 to 100, reactions 101 to 146
  • Henry's Law data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Vibrational and/or electronic energy levels
  • Gas Chromatography
  • Fluid Properties
• Data at other public NIST sites:
  • Electron-Impact Ionization Cross Sections (on physics web site)
  • Gas Phase Kinetics Database
  • X-ray Photoelectron Spectroscopy Database, version 5.0
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, "lite" edition (thermophysical and thermochemical data)
• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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Phase change data

Go To: Top, Reaction thermochemistry 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 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

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 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)

Gas phase ion energetics data

Go To: Top, Phase change data, Reaction thermochemistry data, 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)

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

H₂N^- +  =

By formula: H₂N^- + H⁺ = H₃N

References

Go To: Top, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, 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
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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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Arshadi and Futrell, 1974
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Payzant, Cunningham, et al., 1973
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Notes

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

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  Pc	Critical pressure
  Ptriple	Triple point pressure
  T	Temperature
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  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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