Hydrogen iodide

• Formula: HI
• Molecular weight: 127.91241
• IUPAC Standard InChI: InChI=1S/HI/h1H Copy

  
• IUPAC Standard InChIKey: XMBWDFGMSWQBCA-UHFFFAOYSA-N Copy
• CAS Registry Number: 10034-85-2
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Information on this page:
  • Reaction thermochemistry data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Phase change data
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
  • Constants of diatomic molecules
• Data at other public NIST sites:
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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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
MS - José A. Martinho Simões

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.

Individual Reactions

 +  = ( • )

By formula: I^- + HI = (I^- • HI)

Bond type: Hydrogen bond (negative ion to hydride)

Free energy of reaction

 +  =

By formula: I^- + H⁺ = HI

 +  =  + 

By formula: HI + C₃H₅I = C₃H₆ + I₂

 +  =  + 

By formula: HI + CH₃I = CH₄ + I₂

 (l) +  (cr) =  (g) +  (cr)

By formula: C₅HMnO₅ (l) + I₂ (cr) = HI (g) + C₅IMnO₅ (cr)

 +  =  + 

By formula: C₂H₃IO + H₂O = HI + C₂H₄O₂

=  + 

By formula: C₄H₉I = HI + C₄H₈

 +  =  + 

By formula: HI + C₆H₁₁I = C₆H₁₂ + I₂

 +  =  + 

By formula: C₂H₃F₃ + I₂ = HI + C₂H₂F₃I

 +  =  + 

By formula: C₇H₉NO + C₇H₅IO = HI + C₁₄H₁₃NO₂

 +  =  + 

By formula: C₇H₉N + C₇H₅IO = HI + C₁₄H₁₃NO

 +  =  + 

By formula: C₇H₅IO + C₆H₇N = HI + C₁₃H₁₁NO

 (cr) +  (solution) =  (solution) + C₈H₅IO₃W (solution)

By formula: C₈H₆O₃W (cr) + I₂ (solution) = HI (solution) + C₈H₅IO₃W (solution)

C₈H₆MoO₃ (cr) +  (solution) = C₈H₅IMoO₃ (solution) +  (solution)

By formula: C₈H₆MoO₃ (cr) + I₂ (solution) = C₈H₅IMoO₃ (solution) + HI (solution)

2 +  = 2 + 

By formula: 2C₃H₈S + I₂ = 2HI + C₆H₁₄S₂

2 +  = 2 + 

By formula: 2C₅H₁₂S + I₂ = 2HI + C₁₀H₂₂S₂

 +  = 2 + 

By formula: C₄H₁₀S₂ + I₂ = 2HI + C₄H₈S₂

 +  = 2 + 

By formula: C₈H₁₆O₂S₂ + I₂ = 2HI + C₈H₁₄O₂S₂

 +  = 2 + 

By formula: C₃H₈S₂ + I₂ = 2HI + C₃H₆S₂

 +  =  + 

By formula: HI + C₇H₇I = C₇H₈ + I₂

 +  =  + 

By formula: C₃H₅I + H₂O = HI + C₃H₆O

 +  =  + 

By formula: C₇H₇I + H₂O = HI + C₇H₈O

 +  =  + 

By formula: C₇H₅IO + H₂O = HI + C₇H₆O₂

C₃H₉ISn (l) +  (l) = ( • 55) (solution) + C₃H₁₀OSn (cr)

By formula: C₃H₉ISn (l) + H₂O (l) = (HI • 55H₂O) (solution) + C₃H₁₀OSn (cr)

 +  =  + 

By formula: HI + CH₃IS = CH₄S + I₂

 +  =  + 

By formula: C₃H₆O + I₂ = HI + C₃H₅IO

 +  =  + 

By formula: C₂H₄O + I₂ = HI + C₂H₃IO

 +  =  + 

By formula: HI + C₇H₇IO = C₇H₈O + I₂

 +  =  + 

By formula: HI + C₂H₅IS = C₂H₆S + I₂

C₁₀H₁₂W (cr) + 2 (cr) = C₁₀H₁₀I₂W (cr) + 2 (g)

By formula: C₁₀H₁₂W (cr) + 2I₂ (cr) = C₁₀H₁₀I₂W (cr) + 2HI (g)

 +  =  + 

By formula: HI + C₇H₅IO = C₇H₆O + I₂

C₁₀H₁₁ClZr (cr) +  (cr) = C₁₀H₁₀ClIZr (cr) +  (g)

By formula: C₁₀H₁₁ClZr (cr) + I₂ (cr) = C₁₀H₁₀ClIZr (cr) + HI (g)

C₁₀H₁₂Mo (cr) + 2 (cr) = C₁₀H₁₀I₂Mo (cr) + 2 (g)

By formula: C₁₀H₁₂Mo (cr) + 2I₂ (cr) = C₁₀H₁₀I₂Mo (cr) + 2HI (g)

 +  =  + 

By formula: C₂H₄F₂ + I₂ = HI + C₂H₃BrF₂

 +  =  + 

By formula: C₇H₆O + I₂ = HI + C₇H₅IO

 +  =  + 

By formula: HI + C₆H₅I = C₆H₆ + I₂

C₁₀H₁₁IW (cr) +  (cr) = C₁₀H₁₀I₂W (cr) +  (g)

By formula: C₁₀H₁₁IW (cr) + I₂ (cr) = C₁₀H₁₀I₂W (cr) + HI (g)

 (g) +  (g) =  (g) +  (g)

By formula: I (g) + H₄Ge (g) = HI (g) + H₃Ge (g)

 +  = 2 + 

By formula: C₅H₁₀ + I₂ = 2HI + C₅H₈

 +  =  + 

By formula: HI + C₄H₇IO = I₂ + C₄H₈O

2 +  =  + 

By formula: 2HI + C₅H₆ = C₅H₈ + I₂

 +  =

By formula: HI + C₃H₆ = C₃H₇I

 (g) + C₃H₁₀Ge (g) = C₃H₉Ge (g) +  (g)

By formula: I (g) + C₃H₁₀Ge (g) = C₃H₉Ge (g) + HI (g)

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.

Caldwell and Kebarle, 1985
Caldwell, G.; Kebarle, P., The hydrogen bond energies of the bihalide ions XHX- and YHX-, Can. J. Chem., 1985, 63, 1399. [all data]

Pelaez, Blondel, et al., 2009
Pelaez, R.J.; Blondel, C.; Delsart, C.; Drag, C., Pulsed photodetachment microscopy and the electron affinity of iodine, J. Phys. B: Atom. Mol. Opt. Phys., 2009, 42, 12, 125001, https://doi.org/10.1088/0953-4075/42/12/125001 . [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]

Rodgers, Golden, et al., 1966
Rodgers, A.S.; Golden, D.M.; Benson, S.W., The thermochemistry of the gas phase equilibrium I₂ + C₃H₆ = C₃H₅I + HI, J. Am. Chem. Soc., 1966, 88, 3194-3196. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

Golden, Walsh, et al., 1965
Golden, D.M.; Walsh, R.; Benson, S.W., The thermochemistry of the gas phase equilibrium I₂ + CH₄ «=» CH₃I + HI and the heat of formation of the methyl radical, J. Am. Chem. Soc., 1965, 87, 4053-4057. [all data]

Goy and Pritchard, 1965
Goy, C.A.; Pritchard, H.O., Kinetics and thermodynamics of the reaction between iodine and methane and the heat of formation of methyl iodide, J. Phys. Chem., 1965, 69, 3040-3041. [all data]

Nichol and Ubbelohde, 1952
Nichol, R.J.; Ubbelohde, A.R., A thermochemical evaluation of bond strengths in some carbon compounds. part II. Bond strengths based on the reaction CH₃I + HI = CH₄ + I₂, J. Am. Chem. Soc., 1952, 415-421. [all data]

Connor, Zafarani-Moattar, et al., 1982
Connor, J.A.; Zafarani-Moattar, M.T.; Bickerton, J.; El-Saied, N.I.; Suradi, S.; Carson, R.; Al Takkhin, G.; Skinner, H.A., Organomet., 1982, 1, 1166. [all data]

Devore and O'Neal, 1969
Devore, J.A.; O'Neal, H.E., Heats of formation of the acetyl halides and of the acetyl radical, J. Phys. Chem., 1969, 73, 2644-2648. [all data]

Carson and Skinner, 1949
Carson, A.S.; Skinner, H.A., 201. Carbon-halogen bond energies in the acetyl halides, J. Chem. Soc., 1949, 936-939. [all data]

Benson and Amano, 1962
Benson, S.W.; Amano, A., Thermodynamic properties of tertiary iodides, J. Chem. Phys., 1962, 37, 197-198. [all data]

Jones and Ogg, 1937
Jones, J.L.; Ogg, R.A., Jr., The equilibrium (CH₃)₃CI = (CH₃)₂C = CH₂ + HI, J. Am. Chem. Soc., 1937, 59, 1943-1945. [all data]

Brennan and Ubbelohde, 1956
Brennan, D.; Ubbelohde, A.R., A thermochemical evaluation of bond strengths in some carbon compounds. Part IV. Bond-strength differences based on the reaction: RI + HI = RH + I₂, where R = p-methoxyphenyl and cyclohexyl, J. Chem. Soc., 1956, 3011-3016. [all data]

Wu and Rodgers, 1974
Wu, E.; Rodgers, A.S., Thermochemistry of gas-phase equilibrium CF₃CH₃ + I₂ = CF₃CH₂I + HI. The carbon-hydrogen bond dissociation energy in 1,1,1-trifluoroethane and the heat of formation of the 2,2,2-trifluoroethyl radical, J. Phys. Chem., 1974, 78, 2315-2317. [all data]

Kiselev, Khuzyasheva, et al., 1979
Kiselev, V.D.; Khuzyasheva, d.G.; Konovalov, A.I., Thermochemical study of the acylation of para-substituted anilines, J. Gen. Chem. USSR, 1979, 49, 2273-2276. [all data]

Landrum and Hoff, 1985
Landrum, J.T.; Hoff, C.D., J. Organometal. Chem., 1985, 282, 215. [all data]

Sunner, 1955
Sunner, S., Strain in 6,8-thioctic acid, Nature (London), 1955, 176, 217. [all data]

Graham, Nichol, et al., 1955
Graham, W.S.; Nichol, R.J.; Ubbelohde, A.R., A thermochemical evaluation of bond strengths in some carbon compounds. Part III. Bond strengths based on the reactions: (a) Ph·CH₂I + HI=Ph·CH₃ + I₂ and (b) PhI + HI=PhH + I₂, J. Chem. Soc., 1955, 115-121. [all data]

Gellner and Skinner, 1949
Gellner, O.H.; Skinner, H.A., Dissociation energies of carbon-halogen bonds. The bond strengths allyl-X and benzyl-X, J. Chem. Soc., 1949, 1145-1148. [all data]

Carson, Pritchard, et al., 1950
Carson, A.S.; Pritchard, H.O.; Skinner, H.A., The heats of hydrolysis of the benzoyl halides, J. Chem. Soc., 1950, 656-659. [all data]

Baldwin, Lappert, et al., 1972
Baldwin, J.C.; Lappert, M.F.; Pedley, J.B.; Poland, J.S., J. Chem. Soc., Dalton Trans., 1972, 1943.. [all data]

Shum and Benson, 1983
Shum, L.G.S.; Benson, S.W., Thermochemnistry and kinetics of the reaction of methyl mercaptan with iodine, Int. J. Chem. Kinet., 1983, 15, 433-453. [all data]

Solly, Golden, et al., 1970
Solly, R.K.; Golden, D.M.; Benson, S.W., Thermochemical properties of iodoacetone. Intramolecular electrostatic interactions in polar molecules, J. Am. Chem. Soc., 1970, 92, 4653-4656. [all data]

Walsh and Benson, 1966
Walsh, R.; Benson, S.W., The heats of formation of acetyl iodide and the acetyl radical, J. Phys. Chem., 1966, 70, 3751-3753. [all data]

Shum and Benson, 1985
Shum, L.G.S.; Benson, S.W., Iodine catalyzed pyrolysis of dimethyl sulfide. Heats of formaton of CH₃SCH₂I, the CH₃SCH₂ radical, and the pibond energy in CH₂S, Int. J. Chem. Kinet., 1985, 17, 277-292. [all data]

Calado, Dias, et al., 1979
Calado, J.C.G.; Dias, A.R.; Martinho Simões, J.A.; Ribeiro da Silva, M.A.V., Rev. Port. Quím., 1979, 21, 129. [all data]

Solly and Benson, 1971
Solly, R.K.; Benson, S.W., Thermochemistry of the reaction of benzaldehyde with iodine. The enthalpy of formation of benzaldehyde and benzoyl iodide, J. Chem. Thermodyn., 1971, 3, 203-209. [all data]

Diogo, Simoni, et al., 1993
Diogo, H.P.; Simoni, J.A.; Minas da Piedade, M.E.; Dias, A.R.; Martinho Simões, J.A., J. Am. Chem. Soc., 1993, 115, 2764. [all data]

Pickard and Rodgers, 1977
Pickard, J.M.; Rodgers, A.S., The kinetics and thermochemistry of the reaction of 1,1-difluoroethane with iodine. The difluoromethylene-hydrogen bond dissociation energy in 1,1-difluoroethane and the heat of formation of 1,1-difluoroethyl, J. Am. Chem. Soc., 1977, 99, 691-694. [all data]

Calhorda, Dias, et al., 1987
Calhorda, M.J.; Dias, A.R.; Minas da Piedade M.E.; Salema, M.S.; Martinho Simões J.A., Organometallics, 1987, 6, 734. [all data]

Noble and Walsh, 1983
Noble, P.N.; Walsh, R., Kinetics of the gas phase reaction between iodine and monogermane and the bond dissociation energy D(H₃Ge-H), Int. J. Chem. Kinet., 1983, 15, 547. [all data]

Furuyama, Golden, et al., 1970
Furuyama, S.; Golden, D.M.; Benson, S.W., Thermochemistry of cyclopentene and cyclopentadiene from studies of gas-phase equilibria, J. Chem. Thermodyn., 1970, 2, 161-169. [all data]

Solly, Golden, et al., 1970, 2
Solly, R.K.; Golden, D.M.; Benson, S.W., Kinetics and thermochemistry of the gas phase reaction of methyl ethyl ketone with iodine. II. The heat of formation and unimolecular decomposition of 2-iodo-3-butanone, Int. J. Chem. Kinet., 1970, 2, 393-407. [all data]

Furuyama, Golden, et al., 1969
Furuyama, S.; Golden, D.M.; Benson, S.W., Thermochemistry of the gas phase equilibria i-C₃H₇I = C₃H₆ + HI, n-C₃H₇I = i-C₃H₇I, and C₃H₆ + 2HI = C₃H₈ + I₂, J. Chem. Thermodyn., 1969, 1, 363-375. [all data]

Doncaster and Walsh, 1979
Doncaster, A.M.; Walsh, R., J. Phys. Chem., 1979, 83, 578. [all data]

Notes

Go To: Top, Reaction thermochemistry data, References

• 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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