Chlorine
- Formula: Cl2
- Molecular weight: 70.906
- IUPAC Standard InChIKey: KZBUYRJDOAKODT-UHFFFAOYSA-N
- 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
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Gas phase thermochemistry data
Go To: Top, Phase change data, Reaction thermochemistry data, Henry's Law data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
S°gas,1 bar | 53.3176 ± 0.0024 | cal/mol*K | Review | Cox, Wagman, et al., 1984 | CODATA Review value |
S°gas,1 bar | 53.317 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in June, 1982 |
Gas Phase Heat Capacity (Shomate Equation)
Cp° = 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
Cp = heat capacity (cal/mol*K)
H° = standard enthalpy (kcal/mol)
S° = standard entropy (cal/mol*K)
t = temperature (K) / 1000.
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Temperature (K) | 298. to 1000. | 1000. to 3000. | 3000. to 6000. |
---|---|---|---|
A | 7.899283 | 10.20012 | -10.17053 |
B | 2.922897 | -1.197316 | 9.963122 |
C | -2.883629 | 0.455215 | -1.703354 |
D | 1.048120 | -0.039589 | 0.092696 |
E | -0.038120 | -0.501549 | 24.17400 |
F | -2.589580 | -4.132362 | 31.73136 |
G | 61.90942 | 64.49331 | 63.28537 |
H | 0.000000 | 0.000000 | 0.000000 |
Reference | Chase, 1998 | Chase, 1998 | Chase, 1998 |
Comment | Data last reviewed in June, 1982 | Data last reviewed in June, 1982 | Data last reviewed in June, 1982 |
Phase change data
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Henry's Law 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:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 239.5 | K | N/A | Thiele and Schulte, 1920 | Uncertainty assigned by TRC = 0.6 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 172.17 ± 0.05 | K | N/A | Angus, Armstrong, et al., 1984 | Uncertainty assigned by TRC = 0.05 K; TRC |
Ttriple | 172.12 | K | N/A | Giauque and Powell, 1939 | Uncertainty assigned by TRC = 0.15 K; mean of 5 measurements with thermocouple and Pt res. therm., To = 273.10 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ptriple | 0.01374 ± 0.00003 | atm | N/A | Angus, Armstrong, et al., 1984 | Uncertainty assigned by TRC = 0.00003 atm; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 416.956 | K | N/A | Angus, Armstrong, et al., 1984 | TRC |
Tc | 416.9 | K | N/A | Ambrose, Hall, et al., 1979 | Uncertainty assigned by TRC = 0.5 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 78.869 | atm | N/A | Angus, Armstrong, et al., 1984 | TRC |
Pc | 78.73 | atm | N/A | Ambrose, Hall, et al., 1979 | Uncertainty assigned by TRC = 0.49 atm; Visual, uncertain because of reactivity of element.; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ρc | 8.1344 | mol/l | N/A | Angus, Armstrong, et al., 1984 | TRC |
Antoine Equation Parameters
log10(P) = A − (B / (T + C))
P = vapor pressure (atm)
T = temperature (K)
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Temperature (K) | A | B | C | Reference | Comment |
---|---|---|---|---|---|
155. to 239.4 | 3.0156 | 530.591 | -64.639 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
239.4 to 400.3 | 4.28243 | 969.992 | -12.791 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
Reaction thermochemistry data
Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law 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:
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-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 23.7 ± 1.2 | kcal/mol | CIDT | Nizzi, Pommerening, et al., 1998 | gas phase; B |
ΔrH° | 16.70 | kcal/mol | Ther | Robbiani and Franklin, 1979 | gas phase; ΔG≈+1 kcal for Cl- + SO2Cl2 <=> Cl3- + SO2; B |
ΔrH° | <43.60 | kcal/mol | PDis | Lee, Smith, et al., 1979 | gas phase; B |
By formula: C2Cl4 + Cl2 = C2Cl6
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -36.70 ± 0.60 | kcal/mol | Cm | Kirkbride, 1956 | liquid phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -37. kcal/mol; ALS |
By formula: Cl- + Cl2 = (Cl- • Cl2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 17.0 | kcal/mol | SAMS | Robbiani and Franklin, 1979, 2 | gas phase; based on Cl- + SO2Cl2 <--> Cl3- + SO2; National Bureau of Standards, 1968; M |
By formula: C4F6 + Cl2 = C4Cl2F6
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -37.38 ± 0.99 | kcal/mol | Cm | Lacher, McKinley, et al., 1949 | gas phase; Heat of chlorination at 363 °K; ALS |
By formula: C3F6 + Cl2 = C3Cl2F6
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -47.15 ± 0.12 | kcal/mol | Cm | Lacher, McKinley, et al., 1949 | gas phase; Heat of chlorination at 363 °K; ALS |
By formula: Cl2 + C2ClF3 = C2Cl3F3
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -48.82 ± 0.48 | kcal/mol | Cm | Lacher, McKinley, et al., 1949 | gas phase; Heat of Chlorination at 363 °K; ALS |
By formula: Cl2 + C2Cl2F2 = C2Cl4F2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -41.08 ± 0.56 | kcal/mol | Cm | Lacher, McKinley, et al., 1949 | gas phase; Heat of chlorination at 363 °K; ALS |
By formula: C2F4 + Cl2 = C2Cl2F4
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -57.32 ± 0.20 | kcal/mol | Cm | Lacher, McKinley, et al., 1949, 2 | gas phase; Chlorination at 90 C; ALS |
By formula: C2H4Cl2 + Cl2 = HCl + C2H3Cl3
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -27.8 | kcal/mol | Cm | Kirkbride, 1956 | liquid phase; Heat of chlorination; ALS |
By formula: CHCl3 + Cl2 = CCl4 + HCl
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -22.30 | kcal/mol | Cm | Kirkbride, 1956 | liquid phase; Heat of chlorination; ALS |
By formula: C2H4 + Cl2 = C2H4Cl2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -43.65 ± 0.15 | kcal/mol | Cm | Conn, Kistiakowsky, et al., 1938 | gas phase; At 355 °K; ALS |
By formula: C2H2Cl2 + Cl2 = C2H2Cl4
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -40.4 | kcal/mol | Cm | Kirkbride, 1956 | liquid phase; Heat of chlorination; ALS |
By formula: BrCl + CClF3 = CBrF3 + Cl2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 10.69 ± 0.15 | kcal/mol | Eqk | Coomber and Whittle, 1967 | gas phase; ALS |
+ = C2BrF5 +
By formula: BrCl + C2ClF5 = C2BrF5 + Cl2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 10.3 ± 0.6 | kcal/mol | Eqk | Coomber and Whittle, 1967 | gas phase; ALS |
By formula: C2H2Cl2 = C2H2 + Cl2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 5.1 | kcal/mol | Kin | Laursen and Pimentel, 1989 | gas phase; Photolyses; ALS |
By formula: C4F8 + Cl2 = C4Cl2F8
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -44.97 ± 0.31 | kcal/mol | Cm | Lacher, Kianpour, et al., 1957 | gas phase; ALS |
By formula: C5F10 + Cl2 = C5Cl2F10
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -45.61 ± 0.40 | kcal/mol | Cm | Lacher, Kianpour, et al., 1957, 2 | gas phase; ALS |
By formula: C2Cl6 = C2Cl4 + Cl2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 31.7 ± 1.0 | kcal/mol | Eqk | Puyo, Balesdent, et al., 1963 | gas phase; ALS |
By formula: C4F8 + Cl2 = C4Cl2F8
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -42.22 ± 0.51 | kcal/mol | Cm | Lacher, Kianpour, et al., 1957, 2 | gas phase; ALS |
By formula: C6H11Cl + HCl = C6H12 + Cl2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -34.20 | kcal/mol | Cm | Kirkbride, 1956 | liquid phase; ALS |
By formula: C6H6 + Cl2 = C6H5Cl + HCl
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -32.0 | kcal/mol | Cm | Kirkbride, 1956 | liquid phase; ALS |
By formula: Cl2 + C2HCl3 = C2HCl5
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -36.2 | kcal/mol | Cm | Kirkbride, 1956 | liquid phase; ALS |
Henry's Law data
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: Rolf Sander
Henry's Law constant (water solution)
kH(T) = k°H exp(d(ln(kH))/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(kH))/d(1/T) = Temperature dependence constant (K)
k°H (mol/(kg*bar)) | d(ln(kH))/d(1/T) (K) | Method | Reference | Comment |
---|---|---|---|---|
0.095 | 2100. | L | N/A | |
0.093 | 2600. | Q | N/A | Only the tabulated data between T = 273. K and T = 303. K from missing citation was used to derive kH and -Δ kH/R. Above T = 303. K the tabulated data could not be parameterized by equation (reference missing) very well. The partial pressure of water vapor (needed to convert some Henry's law constants) was calculated using the formula given by missing citation. The quantities A and α from missing citation were assumed to be identical. |
0.061 | 2800. | T | N/A | |
0.085 | 2000. | X | N/A | |
0.091 | 2500. | L | N/A | |
0.062 | 3200. | L | N/A |
References
Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, 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, Henry's Law data, 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 d(ln(kH))/d(1/T) Temperature dependence parameter for Henry's Law constant k°H Henry's Law constant at 298.15K ΔrH° Enthalpy of reaction at standard conditions ρc Critical density - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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