Hypochlorous acid

• Formula: ClHO
• Molecular weight: 52.460
• IUPAC Standard InChI: InChI=1S/ClHO/c1-2/h2H Copy

  
• IUPAC Standard InChIKey: QWPPOHNGKGFGJK-UHFFFAOYSA-N Copy
• CAS Registry Number: 7790-92-3
• 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:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • Henry's Law data
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Gas phase ion energetics data
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Gas Phase Kinetics Database
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Gas phase thermochemistry data

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

Gas Phase Heat Capacity (Shomate Equation)

C_p° = A + B*t + C*t² + D*t³ + E/t²
H° − H°_298.15= A*t + B*t²/2 + C*t³/3 + D*t⁴/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t²/2 + D*t³/3 − E/(2*t²) + G
    C_p = heat capacity (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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Reaction thermochemistry data

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

Data compiled by: 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.

Individual Reactions

ClO^- +  =

By formula: ClO^- + H⁺ = HClO

Henry's Law data

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

Data compiled by: Rolf Sander

Henry's Law constant (water solution)

k_H(T) = k°_H exp(d(ln(k_H))/d(1/T) ((1/T) - 1/(298.15 K)))
k°_H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(k_H))/d(1/T) = Temperature dependence constant (K)

Vibrational and/or electronic energy levels

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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:
J - Marilyn E. Jacox
Shim - Takehiko Shimanouchi

State:   X

Additional references: Jacox, 1994, page 52; Jacox, 1998, page 155; Jacox, 2003, page 45; Mirri, Scappini, et al., 1971; Gillis Singbeil, Anderson, et al., 1984; Anderson, Gerry, et al., 1986; Deeley, 1987; Bellini, De Natale, et al., 1995; Vander Auwera, Kleffmann, et al., 2000; Zheng, Ulenikov, et al., 2001

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Henry's Law data, Vibrational and/or electronic energy levels, Notes

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

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Distelrath and Boesl, 2000
Distelrath, V.; Boesl, U., Mass selective gas phase study of ClO, OClO, ClOO and ClAr by anion-ZEKE-photoelectron spectroscopy, Faraday Disc. Chem. Soc., 2000, 115, 161-174, https://doi.org/10.1039/a909618c . [all data]

Ashby, 1967
Ashby, R.A., The infrared spectrum of HOCl, J. Mol. Spectrosc., 1967, 23, 4, 439, https://doi.org/10.1016/0022-2852(67)90122-1 . [all data]

Su, Calvert, et al., 1979
Su, F.; Calvert, J.G.; Lindley, C.R.; Uselman, W.M.; Shaw, J.H., Fourier transform infrared kinetic study of hypochlorous acid and its absolute integrated infrared band intensities, J. Phys. Chem., 1979, 83, 8, 912, https://doi.org/10.1021/j100471a006 . [all data]

Wells, Sams, et al., 1979
Wells, J.S.; Sams, R.L.; Lafferty, W.J., The high resolution infrared spectrum of the ν1 band of HOCl, J. Mol. Spectrosc., 1979, 77, 3, 349, https://doi.org/10.1016/0022-2852(79)90177-2 . [all data]

Deeley and Mills, 1985
Deeley, C.M.; Mills, I.M., Vibration-rotation spectra and the harmonic force field of HOCl, J. Mol. Spectrosc., 1985, 114, 2, 368, https://doi.org/10.1016/0022-2852(85)90232-2 . [all data]

Junttila, Lafferty, et al., 1994
Junttila, M.-L.; Lafferty, W.J.; Burkholder, J.B., The High-Resolution Spectrum of the ν1 Band and Ground State Rotational Constants of HOCl, J. Mol. Spectrosc., 1994, 164, 2, 583, https://doi.org/10.1006/jmsp.1994.1102 . [all data]

Raston, Kelloway, et al., 2012
Raston, P.L.; Kelloway, D.D.; Jager, W., Infrared spectroscopy of HOCl embedded in superfluid helium nanodroplets: Probing the dynamical response of the solvent, J. Chem. Phys., 2012, 137, 1, 014302, https://doi.org/10.1063/1.4731283 . [all data]

Yoshinobu, Akai, et al., 2009
Yoshinobu, T.; Akai, N.; Kawai, A.; Shibuya, K., Neon matrix-isolation infrared spectrum of HOOCl measured upon the VUV-light irradiation of an HCl/O2 mixture, Chem. Phys. Lett., 2009, 477, 1-3, 70, https://doi.org/10.1016/j.cplett.2009.06.064 . [all data]

Schwager and Arkell, 1967
Schwager, I.; Arkell, A., None, J. Am. Chem. Soc., 1967, 89, 24, 6006, https://doi.org/10.1021/ja01000a002 . [all data]

Hedberg and Badger, 1951
Hedberg, K.; Badger, R.M., The Infrared Spectra of HOCl and DOCl, J. Chem. Phys., 1951, 19, 4, 508, https://doi.org/10.1063/1.1748265 . [all data]

Ashby, 1971
Ashby, R.A., On the infrared spectrum of HOCl, J. Mol. Spectrosc., 1971, 40, 3, 639, https://doi.org/10.1016/0022-2852(71)90264-5 . [all data]

Niki, Maker, et al., 1979
Niki, H.; Maker, P.D.; Savage, C.M.; Breitenbach, L.P., Fourier transform IR spectroscopic determination of the equilibrium constant for H2O + Cl2O = 2HOCl, Chem. Phys. lett., 1979, 66, 2, 325, https://doi.org/10.1016/0009-2614(79)85027-7 . [all data]

Sams and Olson, 1980
Sams, R.L.; Olson, W.B., Analysis of the high-resolution infrared spectrum of the ν2 bending mode of HOCl at 1238 cm-1, J. Mol. Spectrosc., 1980, 84, 1, 113, https://doi.org/10.1016/0022-2852(80)90244-1 . [all data]

Lafferty and Olson, 1986
Lafferty, W.J.; Olson, W.B., The high-resolution infrared spectra of the ν2 and ν3 bands of HOCl, J. Mol. Spectrosc., 1986, 120, 2, 359, https://doi.org/10.1016/0022-2852(86)90010-X . [all data]

Jacox, 1994
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules, American Chemical Society, Washington, DC, 1994, 464. [all data]

Jacox, 1998
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules: supplement A, J. Phys. Chem. Ref. Data, 1998, 27, 2, 115-393, https://doi.org/10.1063/1.556017 . [all data]

Jacox, 2003
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules: supplement B, J. Phys. Chem. Ref. Data, 2003, 32, 1, 1-441, https://doi.org/10.1063/1.1497629 . [all data]

Mirri, Scappini, et al., 1971
Mirri, A.M.; Scappini, F.; Cazzoli, G., Microwave spectrum, structure and electric quadrupole coupling constants of HOCl, J. Mol. Spectrosc., 1971, 38, 2, 218, https://doi.org/10.1016/0022-2852(71)90107-X . [all data]

Gillis Singbeil, Anderson, et al., 1984
Gillis Singbeil, H.E.; Anderson, W.D.; Davis, R.W.; Gerry, M.C.L.; Cohen, E.A.; Pickett, H.M.; Lovas, F.J.; Suenram, R.D., The microwave and millimeter-wave spectra of hypochlorous acid, J. Mol. Spectrosc., 1984, 103, 2, 466, https://doi.org/10.1016/0022-2852(84)90069-9 . [all data]

Anderson, Gerry, et al., 1986
Anderson, W.D.; Gerry, M.C.L.; Davis, R.W., The microwave spectrum of isotopically substituted hypochlorous acid: Determination of the molecular structure, J. Mol. Spectrosc., 1986, 115, 1, 117, https://doi.org/10.1016/0022-2852(86)90280-8 . [all data]

Deeley, 1987
Deeley, C.M., Vibration-rotation spectra of deuterated hypochlorous acid and the determination of the equilibrium structure, J. Mol. Spectrosc., 1987, 122, 2, 481, https://doi.org/10.1016/0022-2852(87)90022-1 . [all data]

Bellini, De Natale, et al., 1995
Bellini, M.; De Natale, P.; Fusina, L.; Modugno, G., The Pure Rotation Spectrum of HOCl in the Submillimeter-Wave Region, J. Mol. Spectrosc., 1995, 172, 2, 559, https://doi.org/10.1006/jmsp.1995.1202 . [all data]

Vander Auwera, Kleffmann, et al., 2000
Vander Auwera, J.; Kleffmann, J.; Flaud, J.-M.; Pawelke, G.; Burger, H.; Hurtmans, D.; Petrisse, R., Absolute ν2 Line Intensities of HOCl by Simultaneous Measurements in the Infrared with a Tunable Diode Laser and Far-Infrared Region Using a Fourier Transform Spectrometer, J. Mol. Spectrosc., 2000, 204, 1, 36, https://doi.org/10.1006/jmsp.2000.8197 . [all data]

Zheng, Ulenikov, et al., 2001
Zheng, J.-J.; Ulenikov, O.N.; Bekhtereva, E.S.; Ding, Y.; He, S.-G.; Hu, S.-M.; Wang, X.-H.; Zhu, Q.-S., High-Resolution Rotational Analysis of Deuterated Hypochlorous Acid: Ground State, (100), and (020) Vibrational States, J. Mol. Spectrosc., 2001, 209, 1, 105, https://doi.org/10.1006/jmsp.2001.8412 . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Henry's Law data, Vibrational and/or electronic energy levels, References

• Symbols used in this document:
  

  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  d(ln(kH))/d(1/T)	Temperature dependence parameter for Henry's Law constant
  k°H	Henry's Law constant at 298.15K
  ΔfH°gas	Enthalpy of formation of gas 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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