Water

• Formula: H₂O
• Molecular weight: 18.0153
• IUPAC Standard InChI: InChI=1S/H2O/h1H2 Copy

  
• IUPAC Standard InChIKey: XLYOFNOQVPJJNP-UHFFFAOYSA-N Copy
• CAS Registry Number: 7732-18-5
• 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:
  • Deuterium oxide
  • Water-t
  • Water-¹⁸O
  • Water-d
  • Water-t₂
  • Deuterium oxide
• Other names: Water vapor; Distilled water; Ice; H2O; Dihydrogen oxide; steam; Tritiotope
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Reaction thermochemistry data (reactions 251 to 300)
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data: reactions 1 to 50, reactions 51 to 100, reactions 101 to 150, reactions 151 to 200, reactions 201 to 250, reactions 301 to 350, reactions 351 to 400, reactions 401 to 450, reactions 451 to 500, reactions 501 to 550, reactions 551 to 600, reactions 601 to 650, reactions 651 to 700, reactions 701 to 750, reactions 751 to 800, reactions 801 to 850, reactions 851 to 900, reactions 901 to 950, reactions 951 to 1000, reactions 1001 to 1050, reactions 1051 to 1100, reactions 1101 to 1150, reactions 1151 to 1200, reactions 1201 to 1250, reactions 1251 to 1300, reactions 1301 to 1350, reactions 1351 to 1360
  • Gas phase ion energetics 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:
  • Microwave spectra (on physics lab web site)
  • Electron-Impact Ionization Cross Sections (on physics web site)
  • Gas Phase Kinetics Database
  • Reference simulation: SPC/E Water
  • X-ray Photoelectron Spectroscopy Database, version 5.0
• Options:
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• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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Reaction thermochemistry data

Go To: Top, 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
MS - José A. Martinho Simões
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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 251 to 300

( • 2) +  = ( • 3)

By formula: (Cu⁺ • 2H₂O) + H₂O = (Cu⁺ • 3H₂O)

Enthalpy of reaction

( • 3) +  = ( • 4)

By formula: (Cu⁺ • 3H₂O) + H₂O = (Cu⁺ • 4H₂O)

Enthalpy of reaction

C₅H₆N⁺ +  = (C₅H₆N⁺ • )

By formula: C₅H₆N⁺ + H₂O = (C₅H₆N⁺ • H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 2 • ) +  = ( • 3 • )

By formula: (K⁺ • 2H₂O • C₆H₆) + H₂O = (K⁺ • 3H₂O • C₆H₆)

( •  • ) +  = ( • 2 • )

By formula: (K⁺ • H₂O • C₆H₆) + H₂O = (K⁺ • 2H₂O • C₆H₆)

 +  = ( • )

By formula: C₂H₂ClO₂^- + H₂O = (C₂H₂ClO₂^- • H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

 +  = ( • )

By formula: C₃H₅O₃^- + H₂O = (C₃H₅O₃^- • H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

C₂HF₂O₂^- +  = (C₂HF₂O₂^- • )

By formula: C₂HF₂O₂^- + H₂O = (C₂HF₂O₂^- • H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

( • 7) +  = ( • 8)

By formula: (F^- • 7H₂O) + H₂O = (F^- • 8H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

(CH₄NO⁺ • 2) +  = (CH₄NO⁺ • 3)

By formula: (CH₄NO⁺ • 2H₂O) + H₂O = (CH₄NO⁺ • 3H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

(C₄H₁₀NO⁺ • ) +  = (C₄H₁₀NO⁺ • 2)

By formula: (C₄H₁₀NO⁺ • H₂O) + H₂O = (C₄H₁₀NO⁺ • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

(CH₄NO⁺ • ) +  = (CH₄NO⁺ • 2)

By formula: (CH₄NO⁺ • H₂O) + H₂O = (CH₄NO⁺ • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

(HO^- • ) +  = (HO^- • 2)

By formula: (HO^- • H₂O) + H₂O = (HO^- • 2H₂O)

 +  = ( • )

By formula: C₃H₅O₃^- + H₂O = (C₃H₅O₃^- • H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

 +  = ( • )

By formula: C₂H₂IO₂^- + H₂O = (C₂H₂IO₂^- • H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

 +  = ( • )

By formula: C₂H₂FO₂^- + H₂O = (C₂H₂FO₂^- • H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

 +  = ( • )

By formula: C₇H₅O₂^- + H₂O = (C₇H₅O₂^- • H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

(CH₄NO⁺ • 3) +  = (CH₄NO⁺ • 4)

By formula: (CH₄NO⁺ • 3H₂O) + H₂O = (CH₄NO⁺ • 4H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

(CH₄NO⁺ • 4) +  = (CH₄NO⁺ • 5)

By formula: (CH₄NO⁺ • 4H₂O) + H₂O = (CH₄NO⁺ • 5H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

C₂H₅LiO (cr) + 0.5( • 1100) (solution) = 0.5Li₂O₄S (solution) +  (solution)

By formula: C₂H₅LiO (cr) + 0.5(H₂O₄S • 1100H₂O) (solution) = 0.5Li₂O₄S (solution) + C₂H₆O (solution)

C₂H₄NO₂^- +  = C₂H₆NO₃^-

By formula: C₂H₄NO₂^- + H₂O = C₂H₆NO₃^-

( •  • ) +  = ( • 2 • )

By formula: (Cl^- • H₂O • O₂S) + H₂O = (Cl^- • 2H₂O • O₂S)

Bond type: Hydrogen bond (negative ion to hydride)

( • 5) +  = ( • 6)

By formula: (F^- • 5H₂O) + H₂O = (F^- • 6H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

( • 6) +  = ( • 7)

By formula: (F^- • 6H₂O) + H₂O = (F^- • 7H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

( • 8) +  = ( • 9)

By formula: (F^- • 8H₂O) + H₂O = (F^- • 9H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

ClO₄^- +  = (ClO₄^- • )

By formula: ClO₄^- + H₂O = (ClO₄^- • H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

CH₅O⁺ +  = (CH₅O⁺ • )

By formula: CH₅O⁺ + H₂O = (CH₅O⁺ • H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

C₂H₅KO (cr) + 0.5( • 1100) (solution) =  (solution) + 0.5K₂O₄S (solution)

By formula: C₂H₅KO (cr) + 0.5(H₂O₄S • 1100H₂O) (solution) = C₂H₆O (solution) + 0.5K₂O₄S (solution)

(C₂H₇O⁺ •  • 2) +  = (C₂H₇O⁺ • 2 • 2)

By formula: (C₂H₇O⁺ • C₂H₆O • 2H₂O) + C₂H₆O = (C₂H₇O⁺ • 2C₂H₆O • 2H₂O)

Bond type: Hydrogen bonds of the type OH-O between organics

C₄H₁₀NO⁺ +  = (C₄H₁₀NO⁺ • )

By formula: C₄H₁₀NO⁺ + H₂O = (C₄H₁₀NO⁺ • H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

CH₄NO⁺ +  = (CH₄NO⁺ • )

By formula: CH₄NO⁺ + H₂O = (CH₄NO⁺ • H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 2) +  = ( •  • 2)

By formula: (Cl^- • 2O₂S) + H₂O = (Cl^- • H₂O • 2O₂S)

Bond type: Hydrogen bond (negative ion to hydride)

( • 2) +  = ( •  • 2)

By formula: (Cl^- • 2HCl) + H₂O = (Cl^- • H₂O • 2HCl)

Bond type: Hydrogen bond (negative ion to hydride)

( • ) +  = ( •  • )

By formula: (Cl^- • HCl) + H₂O = (Cl^- • H₂O • HCl)

Bond type: Hydrogen bond (negative ion to hydride)

( •  • 2) +  = ( • 2 • 2)

By formula: (K⁺ • H₂O • 2C₆H₆) + H₂O = (K⁺ • 2H₂O • 2C₆H₆)

 +  =  + 

By formula: C₂H₃ClO + H₂O = C₂H₄O₂ + HCl

(C₂H₄N⁺ • ) +  = (C₂H₄N⁺ • 2)

By formula: (C₂H₄N⁺ • H₂O) + H₂O = (C₂H₄N⁺ • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

(C₂H₈N⁺ • 2) +  = (C₂H₈N⁺ • 3)

By formula: (C₂H₈N⁺ • 2H₂O) + H₂O = (C₂H₈N⁺ • 3H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

(C₃H₁₀N⁺ • 2) +  = (C₃H₁₀N⁺ • 3)

By formula: (C₃H₁₀N⁺ • 2H₂O) + H₂O = (C₃H₁₀N⁺ • 3H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

(C₆H₁₈N₂⁺² • ) +  = (C₆H₁₈N₂⁺² • 2)

By formula: (C₆H₁₈N₂⁺² • H₂O) + H₂O = (C₆H₁₈N₂⁺² • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

 +  =  + 2

By formula: C₅H₁₂O₄ + H₂O = C₃H₆O₃ + 2CH₄O

(C₁₀H₂₆N₂⁺² • ) +  = (C₁₀H₂₆N₂⁺² • 2)

By formula: (C₁₀H₂₆N₂⁺² • H₂O) + H₂O = (C₁₀H₂₆N₂⁺² • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

(C₁₂H₃₀N₂ • ) +  = (C₁₂H₃₀N₂ • 2)

By formula: (C₁₂H₃₀N₂ • H₂O) + H₂O = (C₁₂H₃₀N₂ • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

(C₂H₈N⁺ • ) +  = (C₂H₈N⁺ • 2)

By formula: (C₂H₈N⁺ • H₂O) + H₂O = (C₂H₈N⁺ • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

(C₃H₁₀N⁺ • ) +  = (C₃H₁₀N⁺ • 2)

By formula: (C₃H₁₀N⁺ • H₂O) + H₂O = (C₃H₁₀N⁺ • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

(C₃H₉O⁺ • 6) +  = (C₃H₉O⁺ • 7)

By formula: (C₃H₉O⁺ • 6H₂O) + H₂O = (C₃H₉O⁺ • 7H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

(C₇H₂₂⁺² • ) +  = (C₇H₂₂⁺² • 2)

By formula: (C₇H₂₂⁺² • H₂O) + H₂O = (C₇H₂₂⁺² • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

(C₈H₂₂N₂⁺² • ) +  = (C₈H₂₂N₂⁺² • 2)

By formula: (C₈H₂₂N₂⁺² • H₂O) + H₂O = (C₈H₂₂N₂⁺² • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

(C₉H₂₄N₂⁺² • ) +  = (C₉H₂₄N₂⁺² • 2)

By formula: (C₉H₂₄N₂⁺² • H₂O) + H₂O = (C₉H₂₄N₂⁺² • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 12) +  = ( • 13)

By formula: (H₃O⁺ • 12H₂O) + H₂O = (H₃O⁺ • 13H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

References

Go To: Top, Reaction thermochemistry data, Notes

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

Magnera, David, et al., 1989
Magnera, T.F.; David, D.E.; Stulik, D.; Orth, R.G.; Jorikman, H.T.; Michl, J., Production of Hydrated Metal Ions by Fast Ion or Atom Beam Sputtering. Collision - Induced Dissociation and Successive Hydration Energies of Gaseous Cu+ with 1 - 4 Water Molecules, J. Am. Chem. Soc., 1989, 111, 14, 5036, https://doi.org/10.1021/ja00196a003 . [all data]

Holland and Castleman, 1982
Holland, P.M.; Castleman, A.W., The Thermochemical Properties of Gas - Phase Transition Metal Ion Complexes, J. Chem. Phys., 1982, 76, 8, 4195, https://doi.org/10.1063/1.443497 . [all data]

Armentrout and Kickel, 1994
Armentrout, P.B.; Kickel, B.L., Gas Phase Thermochemistry of Transition Metal Ligand Systems: Reassessment of Values and Periodic Trends, in Organometallic Ion Chemistry, B. S. Freiser, ed, 1994. [all data]

Meot-Ner M. and Sieck, 1983
Meot-Ner M.; Sieck, L.W., The Ionic Hydrogen Bond. 1. Sterically Hindered Bonds. Solvation and Clustering of Sterically Hindered Amines and Pyridines, J. Am. Chem. Soc., 1983, 105, 10, 2956, https://doi.org/10.1021/ja00348a005 . [all data]

Davidson, Sunner J., et al., 1979
Davidson, W.R.; Sunner J.; Kebarle, P., Hydrogen Bonding of Water to Onium Ions. Hydration of Substituted Pyridinium Ions and Related Systems, J. Am. Chem. Soc., 1979, 101, 7, 1675, https://doi.org/10.1021/ja00501a005 . [all data]

Sunner, Nishizawa, et al., 1981
Sunner, J.; Nishizawa, K.; Kebarle, P., Ion - Solvent Molecule Interactions in the Gas Phase. Potassium Ion and Benzene, J. Phys. Chem., 1981, 85, 13, 1814, https://doi.org/10.1021/j150613a011 . [all data]

Searles and Kebarle, 1969
Searles, S.K.; Kebarle, P., Hydration of the Potassium Ion in the Gas Phase: Enthalpies and Entropies of Hydration Reactions K+(H2O)n-1 + H2O = K+(H2O)n for n=1 to n=6, Can. J. Chem., 1969, 47, 14, 2619, https://doi.org/10.1139/v69-432 . [all data]

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Blades, A.T.; Klassen, J.S.; Kebarle, P., Free Energies of Hydration in the Gas Phase on the Anions of Some Oxo Acids of C, N, S, P, Cl and I, J. Am. Chem. Soc., 1995, 117, 42, 10563, https://doi.org/10.1021/ja00147a019 . [all data]

Hiraoka, Mizuse, et al., 1988
Hiraoka, K.; Mizuse, S.; Yamabe, S., Solvation of Halide Ions with H₂O and CH₃CN in the Gas Phase, J. Phys. Chem., 1988, 92, 13, 3943, https://doi.org/10.1021/j100324a051 . [all data]

Meot-Ner (Mautner), 1984
Meot-Ner (Mautner), M., The Ionic Hydrogen Bond and Ion Solvation. 2. Hydration of Onium Ions by 1 - 7 H2O Molecules. Relations Between Monomolecular, Specific and Bulk Hydration, J. Am. Chem. Soc., 1984, 106, 5, 1265, https://doi.org/10.1021/ja00317a016 . [all data]

Meot-Ner, 1984
Meot-Ner, (Mautner), The Ionic Hydrogen Bond. 4. Intramolecular and Multiple Bonds. Proton Affinities, Hydration and Complexes of Amides and Amino Acid Derivatives, J. Am. Chem. Soc., 1984, 106, 2, 278, https://doi.org/10.1021/ja00314a003 . [all data]

Meot-Ner (Mautner) and Speller, 1986
Meot-Ner (Mautner), M.; Speller, C.V., The Filling of Solvent Shells in Cluster Ions: Thermochemical Criteria nd the Effects of Isomeric Clusters, J. Phys. Chem., 1986, 90, 25, 6616, https://doi.org/10.1021/j100283a006 . [all data]

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Nieckarz, R.J.; Atkins, C.G.; McMahon, T.B., Effects of Isomerization on the Measured Thermochemical Properties of Deprotonated Glycine/Protic-Solvent Clusters, Chemphyschem, 2008, 9, 18, 2816-2825, https://doi.org/10.1002/cphc.200800525 . [all data]

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Wincel, H., Hydration energies of deprotonated amino acids from gas phase equilibria measurements, J. Am. Soc. Mass Spectrom., 2008, 19, 8, 1091-1097, https://doi.org/10.1016/j.jasms.2008.05.014 . [all data]

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Wiberg, K.B.; Squires, R.R., A microprocessor-controlled system for precise measurement of temperature changes. Determination of the enthalpies of hydrolysis of some polyoxygenated hydrocarbons, J. Chem. Thermodyn., 1979, 11, 773-786. [all data]

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Shi, Z.; Ford, V.; Wei, S.; Castleman, A.W., Water Clusters - Contributions of Binding Energy and Entropy to Stability, J. Chem. Phys., 1993, 99, 10, 8009, https://doi.org/10.1063/1.465678 . [all data]

Magnera, David, et al., 1991
Magnera, T.F.; David, D.E.; Michl, J., The First Twenty - Eight Proton Hydration Energies, Chem. Phys. Lett., 1991, 182, 3-4, 363, https://doi.org/10.1016/0009-2614(91)80230-U . [all data]

Notes

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• Symbols used in this document:
  

  T	Temperature
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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