Iodine

• Formula: I₂
• Molecular weight: 253.80894
• IUPAC Standard InChI: InChI=1S/I2/c1-2 Copy

  
• IUPAC Standard InChIKey: PNDPGZBMCMUPRI-UHFFFAOYSA-N Copy
• CAS Registry Number: 7553-56-2
• 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.
• Other names: I2; Eranol; Iode; Iodine-127; Iodio; Iosan Superdip; Jod; Jood; Molecular iodine; Tincture iodine; Vistarin; Iodine crystals; Iodine sublimed; Diiodine; Diatomic iodine
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• Information on this page:
  • Reaction thermochemistry data (reactions 51 to 75)
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data: reactions 1 to 50
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
  • Constants of diatomic molecules
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
  • X-ray Photoelectron Spectroscopy Database, version 5.0
  • X-ray Photoelectron Spectroscopy Database, version 5.0
  • X-ray Photoelectron Spectroscopy Database, version 5.0
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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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
MS - José A. Martinho Simões
B - John E. Bartmess

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 51 to 75

 +  =  + 

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)

=  + 0.5

By formula: C₇H₇I = C₇H₈ + 0.5I₂

 +  =  + 

By formula: HI + C₇H₅IO = C₇H₆O + I₂

 (cr) +  (cr) = C₁₀H₁₀I₂Ti (cr) + 2 (g)

By formula: C₁₂H₁₀O₂Ti (cr) + I₂ (cr) = C₁₀H₁₀I₂Ti (cr) + 2CO (g)

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)

C₁₂H₁₄Mo (cr) +  (cr) = C₁₀H₁₀I₂Mo (cr) +  (g)

By formula: C₁₂H₁₄Mo (cr) + I₂ (cr) = C₁₀H₁₀I₂Mo (cr) + C₂H₄ (g)

I₃^- +  = (I₃^- • )

By formula: I₃^- + I₂ = (I₃^- • I₂)

 +  = 2 + 

By formula: C₅H₁₀ + I₂ = 2HI + C₅H₈

 +  =  + 

By formula: HI + C₄H₇IO = I₂ + C₄H₈O

2 +  =  + 

By formula: 2HI + C₅H₆ = C₅H₈ + I₂

=  + 

By formula: C₄H₆I₂ = C₄H₆ + I₂

=  + 

By formula: C₃H₆I₂ = C₃H₆ + I₂

=  + 

By formula: C₂H₄I₂ = C₂H₄ + I₂

=  + 

By formula: C₃H₆I₂ = C₃H₆ + I₂

 +  =

By formula: C₄H₈ + I₂ = C₄H₈I₂

=  + 

By formula: C₂H₂I₂ = C₂H₂ + I₂

C₂H₂I₂ =  + 

By formula: C₂H₂I₂ = C₂H₂ + I₂

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.

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]

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]

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]

Ashcroft, Carson, et al., 1963
Ashcroft, S.J.; Carson, A.S.; Pedley, J.B., Thermochemistry of reductions caused by lithium aluminium hydride. Part 2.-The heats of formation of benzyl bromide, benzyl iodide and the benzyl radical, Trans. Faraday Soc., 1963, 59, 2713-2717. [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]

Dias, Dias, et al., 1987
Dias, A.R.; Dias, P.B.; Diogo, H.P.; Galvão, A.M.; Minas da Piedade, M.E.; Martinho Simões, J.A., Organometallics, 1987, 6, 1427. [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]

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]

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]

Calhorda, Carrondo, et al., 1991
Calhorda, M.J.; Carrondo, M.A.A.F.C.T.; Dias, A.R.; Galvão, A.M.; Garcia, M.H.; Martins, A.M.; Minas da Piedade, M.E.; Pinheiro, C.I.; Romão, C.C.; Martinho Simões, J.A.; Veiros, L.F., Organometallics, 1991, 10, 483. [all data]

Do, Klein, et al., 1997
Do, K.; Klein, T.P.; Pommerening, C.A.; Sunderlin, L.S., A New Flowing Afterglow-Guided Ion Beam Tandem Mass Spectrometer. Applications to the Thermochemistry of Polyiodide Ions, J. Am. Soc. Mass Spectrom., 1997, 8, 7, 688, https://doi.org/10.1016/S1044-0305(97)00116-5 . [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
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]

Sunner and Wulff, 1973
Sunner, S.; Wulff, C.A., Ring strain in diiodocyclobutane, Acta Chem. Scand., 1973, 27, 315-317. [all data]

Benson and Amano, 1962
Benson, S.W.; Amano, A., Thermodynamics of iodine addition to ethylene, propylene, and cyclopropane, J. Chem. Phys., 1962, 36, 3464-3471. [all data]

Cline and Kistiakowsky, 1937
Cline, J.E.; Kistiakowsky, G.B., The gaseous equilibrium of 1,2-diiodobutane, butene-1 and iodine, J. Chem. Phys., 1937, 5, 990. [all data]

Furuyama, Golden, et al., 1968
Furuyama, S.; Golden, D.M.; Benson, S.W., The thermochemistry of the gas-phase equilibria trans-1,2-diiodoethylene = acetylene + I₂ and trans-1,2-diiodoethylene = cis-1,2-diiodoethylene, J. Phys. Chem., 1968, 72, 3204-3208. [all data]

Notes

Go To: Top, Reaction thermochemistry data, References

• Symbols used in this document:
  

  ΔrH°	Enthalpy of reaction at standard conditions

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