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
  • Henry's Law data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data
  • Vibrational and/or electronic energy levels
• 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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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)

Gas phase ion energetics 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 as indicated in comments:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Ionization energy determinations

De-protonation reactions

ClO^- +  =

By formula: ClO^- + H⁺ = HClO

References

Go To: Top, Gas phase thermochemistry data, Henry's Law 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.

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

Colbourne, Frost, et al., 1978
Colbourne, D.; Frost, D.C.; McDowell, C.A.; Westwood, N.P.C., The photoelectron spectra of the isoelectronic molecules hypochlorous acid HOCl chloramine NH₂Cl, J. Chem. Phys., 1978, 68, 3574. [all data]

Fisher, 1967
Fisher, I.P., Mass spectrometry study of intermediates in thermal decomposition of perchloric acid and chlorine dioxide, J. Chem. Soc. Faraday Trans., 1967, 63, 684. [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]

Notes

Go To: Top, Gas phase thermochemistry data, Henry's Law data, Gas phase ion energetics data, 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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