Chlorine

• Formula: Cl₂
• Molecular weight: 70.906
• IUPAC Standard InChI: InChI=1S/Cl2/c1-2 Copy

  
• IUPAC Standard InChIKey: KZBUYRJDOAKODT-UHFFFAOYSA-N Copy
• CAS Registry Number: 7782-50-5
• 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: Cl2; Bertholite; Chloor; Chlor; Chlore; Chlorine mol.; Cloro; Molecular chlorine; UN 1017; Diatomic chlorine
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • 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
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, "lite" edition (thermophysical and thermochemical data)
• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Gas phase thermochemistry data

Go To: Top, Phase change data, Reaction thermochemistry data, Mass spectrum (electron ionization), References, Notes

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 (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

View plot Requires a JavaScript / HTML 5 canvas capable browser.

View table.

Phase change data

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Mass spectrum (electron ionization), 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:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

View plot Requires a JavaScript / HTML 5 canvas capable browser.

Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Phase change data, Mass spectrum (electron ionization), 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
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias

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

 +  = Cl₃^-

By formula: Cl^- + Cl₂ = Cl₃^-

 +  =

By formula: C₂Cl₄ + Cl₂ = C₂Cl₆

 +  = ( • )

By formula: Cl^- + Cl₂ = (Cl^- • Cl₂)

 +  =

By formula: C₄F₆ + Cl₂ = C₄Cl₂F₆

 +  =

By formula: C₃F₆ + Cl₂ = C₃Cl₂F₆

 +  =

By formula: Cl₂ + C₂ClF₃ = C₂Cl₃F₃

 +  =

By formula: Cl₂ + C₂Cl₂F₂ = C₂Cl₄F₂

 +  =

By formula: C₂F₄ + Cl₂ = C₂Cl₂F₄

 +  =  + 

By formula: C₂H₄Cl₂ + Cl₂ = HCl + C₂H₃Cl₃

 +  =  + 

By formula: CHCl₃ + Cl₂ = CCl₄ + HCl

 +  =

By formula: C₂H₄ + Cl₂ = C₂H₄Cl₂

 +  =

By formula: C₂H₂Cl₂ + Cl₂ = C₂H₂Cl₄

 +  =  + 

By formula: BrCl + CClF₃ = CBrF₃ + Cl₂

 +  = C₂BrF₅ + 

By formula: BrCl + C₂ClF₅ = C₂BrF₅ + Cl₂

=  + 

By formula: C₂H₂Cl₂ = C₂H₂ + Cl₂

 +  =

By formula: C₄F₈ + Cl₂ = C₄Cl₂F₈

C₅F₁₀ +  = C₅Cl₂F₁₀

By formula: C₅F₁₀ + Cl₂ = C₅Cl₂F₁₀

=  + 

By formula: C₂Cl₆ = C₂Cl₄ + Cl₂

 +  =

By formula: C₄F₈ + Cl₂ = C₄Cl₂F₈

 +  =  + 

By formula: C₆H₁₁Cl + HCl = C₆H₁₂ + Cl₂

 +  =  + 

By formula: C₆H₆ + Cl₂ = C₆H₅Cl + HCl

 +  =

By formula: Cl₂ + C₂HCl₃ = C₂HCl₅

Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction 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 compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

Additional Data

References

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Mass spectrum (electron ionization), Notes

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

Cox, Wagman, et al., 1984
Cox, J.D.; Wagman, D.D.; Medvedev, V.A., CODATA Key Values for Thermodynamics, Hemisphere Publishing Corp., New York, 1984, 1. [all data]

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

Thiele and Schulte, 1920
Thiele, A.; Schulte, E., Binary equilibrium systems with solid carbon dioxide, Z. Phys. Chem., Stoechiom. Verwandtschaftsl., 1920, 96, 312-42. [all data]

Angus, Armstrong, et al., 1984
Angus, S.; Armstrong, B.; de Reuck, K.M., International Thermodynamic Tables of the Fluid State - Chlorine, Pergamon, Oxford, 1984. [all data]

Giauque and Powell, 1939
Giauque, W.F.; Powell, T.M., Chlorine. The Heat Capacity, Vapor Pressure, Heats of Fusion and Vaporiza- tion, and Entropy, J. Am. Chem. Soc., 1939, 61, 1970. [all data]

Ambrose, Hall, et al., 1979
Ambrose, D.; Hall, D.J.; Lee, D.A.; Lewis, G.B., Vapor pressure of chlorine, J. Chem. Thermodyn., 1979, 11, 1089. [all data]

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [all data]

Nizzi, Pommerening, et al., 1998
Nizzi, K.E.; Pommerening, C.A.; Sunderlin, L.S., Gas-phase thermochemistry of polyhalide anions, J. Phys. Chem. A, 1998, 102, 39, 7674-7679, https://doi.org/10.1021/jp9824508 . [all data]

Robbiani and Franklin, 1979
Robbiani, R.; Franklin, J.L., Formation of the trihalide ion Cl₃- in the gas phase, J. Am. Chem. Soc., 1979, 101, 764. [all data]

Lee, Smith, et al., 1979
Lee, L.C.; Smith, G.P.; Moseley, J.T.; Cosby, P.C.; Guest, J.A., Photodissociation and photodetachment of Cl₂-, ClO-, Cl₃-, and BrCl₂-, J. Chem. Phys., 1979, 70, 3237. [all data]

Kirkbride, 1956
Kirkbride, F.W., The heats of chlorination of some hydrocarbons and their chloro-derivatives, J. Appl. Chem., 1956, 6, 11-21. [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]

Robbiani and Franklin, 1979, 2
Robbiani, R.; Franklin, J.L., Negative ion-molecule reaction in sulfuryl halides, J. Am. Chem. Soc., 1979, 101, 3709. [all data]

National Bureau of Standards, 1968
National Bureau of Standards, US, Technical Note 270 - 3 in The NBS Tables of Chemical Thermodynamic Properties, 1968. [all data]

Lacher, McKinley, et al., 1949
Lacher, J.R.; McKinley, J.J.; Walden, C.; Lea, K.; Park, J.D., Reaction heats of organic fluorine compounds. II. The vapor phase heats of chlorination of some simple fluoroolefins, J. Am. Chem. Soc., 1949, 71, 1334-1337. [all data]

Lacher, McKinley, et al., 1949, 2
Lacher, J.R.; McKinley, J.J.; Snow, C.M.; Michel, L.; Nelson, G.; Park, J.D., Reaction heats of organic fluorine compounds. I. Apparatus and the heat of chlorination of tetrafluoroethylene, J. Am. Chem. Soc., 1949, 71, 1330-1334. [all data]

Conn, Kistiakowsky, et al., 1938
Conn, J.B.; Kistiakowsky, G.B.; Smith, E.A., Heats of organic reactions. VII. Addition of halogens to olefins, J. Am. Chem. Soc., 1938, 60, 2764-2771. [all data]

Coomber and Whittle, 1967
Coomber, J.W.; Whittle, E., Bond dissociation energies from equilibrium studies. Part 3.-D(CF₃-Cl), D(C₂F₅-Cl) and the enthalpy of formation of CF₃Cl, Trans. Faraday Soc., 1967, 63, 2656-2667. [all data]

Laursen and Pimentel, 1989
Laursen, S.L.; Pimentel, G.C., Matrix-induced intersystem crossing in the photochemistry of the 1,2-dichloroethenes, J. Phys. Chem., 1989, 93, 2328-2333. [all data]

Lacher, Kianpour, et al., 1957
Lacher, J.R.; Kianpour, A.; Park, J.D., Reaction heats of organic halogen compounds. X. Vapor phase heats of hydrobromination of cyclopropane and propylene, J. Phys. Chem., 1957, 61, 1124-1125. [all data]

Lacher, Kianpour, et al., 1957, 2
Lacher, J.R.; Kianpour, A.; Park, J.D., Reaction heats of organic halogen compounds. VIII. The heats of chlorination of perfluorinated butene-1 pentene-1 and isobutene, J. Phys. Chem., 1957, 61, 584-586. [all data]

Puyo, Balesdent, et al., 1963
Puyo, J.; Balesdent, D.; Niclause, M.; Dzierzynski, M., Etude analytique et thermodynamique de la pyrolyse de l'hexachloroethane en phase gazeuse., Compt. Rend., 1963, 256, 3471-3473. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  Pc	Critical pressure
  Ptriple	Triple point pressure
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  Tboil	Boiling point
  Tc	Critical temperature
  Ttriple	Triple point temperature
  ΔrH°	Enthalpy of reaction at standard conditions
  ρc	Critical density

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.