Hydroquinone

• Formula: C₆H₆O₂
• Molecular weight: 110.1106
• IUPAC Standard InChI: InChI=1S/C6H6O2/c7-5-1-2-6(8)4-3-5/h1-4,7-8H Copy

  
• IUPAC Standard InChIKey: QIGBRXMKCJKVMJ-UHFFFAOYSA-N Copy
• CAS Registry Number: 123-31-9
• 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: 1,4-Benzenediol; p-Benzenediol; p-Dihydroxybenzene; p-Dioxybenzene; p-Hydroquinone; p-Hydroxyphenol; Arctuvin; Benzohydroquinone; Benzoquinol; Diak 5; Eldopaque; Eldoquin; Hidroquinone; Hydroquinol; HE 5; Phiaquin; Quinol; Tecquinol; Tenox HQ; 1,4-Dihydroxybenzene; 4-Hydroxyphenol; p-Dioxobenzene; Hydrochinone; Benzene, p-dihydroxy-; Black and White Bleaching Cream; Derma-Blanch; Hydrochinon; Hydroquinole; Idrochinone; NCI-C55834; Tequinol; USAF EK-356; 1,4-Dihydroxy-benzeen; 1,4-Dihydroxy-benzol; 1,4-Dihydroxybenzen; 1,4-Diidrobenzene; UN 2662; Dihydroquinone; Aida; Eldopacque; Eldopaque forte; Eldoquin forte; Solaquin forte; p-Dihydroquinone; Black & White Bleaching Cream; 1,4-Benzenediol (hydroquinone); Artra (Salt/Mix)
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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • X-ray Photoelectron Spectroscopy Database, version 5.0
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Gas phase thermochemistry data

Go To: Top, Condensed phase 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Constant pressure heat capacity of gas

Condensed phase thermochemistry data

Go To: Top, Gas phase 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of solid

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase 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:
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
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

View reactions leading to C₆H₆O₂⁺ (ion structure unspecified)

Ionization energy determinations

De-protonation reactions

C₆H₅O₂^- +  =

By formula: C₆H₅O₂^- + H⁺ = C₆H₆O₂

References

Go To: Top, Gas phase thermochemistry data, Condensed phase 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.

Sabbah and Buluku, 1991
Sabbah, R.; Buluku, E.N.L.E., Thermodynamic study of three isomers of dihydroxybenzene, Can. J. Chem., 1991, 69, 481-488. [all data]

Pilcher and Sutton, 1956
Pilcher, G.; Sutton, L.E., The heats of combustion of quinol and p-benzoquinone and the thermodynamic quantities of the oxidation-reduction reaction, J. Chem. Soc., 1956, 2695-2700. [all data]

Parks, Manchester, et al., 1954
Parks, G.S.; Manchester, K.E.; Vaughan, L.M., Heats of combustion and formation of some alcohols, phenols, and ketones, J. Chem. Phys., 1954, 22, 2089-2090. [all data]

Pushin, 1954
Pushin, N.A., Heats of combustion and heats of formation of isomeric organic compounds, Bull. Soc. Chim. Belgrade, 1954, 19, 531-547. [all data]

Schreiner, 1925
Schreiner, E., Thermodynamics of the quinhydrone electrode and the chemical constant of hydrogen, Z. Phys. Chem., 1925, 117, 57-87. [all data]

Kudchadker S.A., 1979
Kudchadker S.A., Ideal gas thermodynamic properties of benzene diols: pyrocatechol, resorcinol, and hydroquinone, Thermochim. Acta, 1979, 30, 319-326. [all data]

Bret-Dibat and Lichanot, 1989
Bret-Dibat, P.; Lichanot, A., Thermodynamic properties of positional isomers of disubstituted benzene in condensed phase, Thermochim. Acta, 1989, 147(2), 261-271. [all data]

Ueberreiter and Orthmann, 1950
Ueberreiter, K.; Orthmann, H.-J., Specifische Wärme, spezifisches Volumen, Temperatur- und Wärme-leittähigkeit einiger disubstituierter Benzole und polycyclischer Systeme, Z. Natursforsch. 5a, 1950, 101-108. [all data]

Satoh and Sogabe, 1941
Satoh, S.; Sogabe, T., The heat capacities of some organic compounds containing nitrogen and the atomic heat of nitrogen. (3), Sci., Pap. Inst. Phys. Chem. Res. (Tokyo), 1941, 38, 238-245. [all data]

Andrews, Lynn, et al., 1926
Andrews, D.H.; Lynn, G.; Johnston, J., The heat capacities and heat of crystallization of some isomeric aromatic compounds, J. Am. Chem. Soc., 1926, 48, 1274-1287. [all data]

Andrews, 1926
Andrews, D.H., The specific heats of some isomers of the type ortho, meta and para C6H4XY from 110 to 340K, J. Am. Chem. Soc., 1926, 48, 1287-1298. [all data]

Lange, 1924
Lange, F., Untersuchungen über die spezifische Wärme bei tiefen Temperaturen, Z. Phys. Chem., 1924, 110, 343-362. [all data]

Oikawa, Abe, et al., 1985
Oikawa, A.; Abe, H.; Mikami, N.; Ito, M., Electronic spectra and ionization potentials of rotational isomers of severaldDisubstituted benzenes, Chem. Phys. Lett., 1985, 116, 50. [all data]

Potapov, Kardash, et al., 1972
Potapov, V.K.; Kardash, I.E.; Sorokin, V.V.; Sokolov, S.A.; Evlasheva, T.I., Photoionization of heteroaromatic compounds, Khim. Vys. Energ., 1972, 6, 392. [all data]

Potapov and Sorokin, 1971
Potapov, V.K.; Sorokin, V.V., Photoionization and ion-molecule reactions in quinones and alcohols, High Energy Chem., 1971, 5, 435, In original 487. [all data]

Palmer, Moyes, et al., 1979
Palmer, M.H.; Moyes, W.; Speirs, M.; Ridyard, J.N.A., The electronic structure of substituted benzenes; ab initio calculations and photoelectron spectra for phenol, the methyl- and fluoro-derivatives, and the dihydroxybenzenes, J. Mol. Struct., 1979, 52, 293. [all data]

Fujio, McIver, et al., 1981
Fujio, M.; McIver, R.T., Jr.; Taft, R.W., Effects on the acidities of phenols from specific substituent-solvent interactions. Inherent substituent parameters from gas phase acidities, J. Am. Chem. Soc., 1981, 103, 4017. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  Cp,gas	Constant pressure heat capacity of gas
  Cp,solid	Constant pressure heat capacity of solid
  IE (evaluated)	Recommended ionization energy
  S°gas	Entropy of gas at standard conditions
  ΔcH°solid	Enthalpy of combustion of solid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°solid	Enthalpy of formation of solid at standard conditions
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

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