Acetylene

• Formula: C₂H₂
• Molecular weight: 26.0373
• IUPAC Standard InChI: InChI=1S/C2H2/c1-2/h1-2H Copy

  
• IUPAC Standard InChIKey: HSFWRNGVRCDJHI-UHFFFAOYSA-N Copy
• CAS Registry Number: 74-86-2
• 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: Ethyne; Ethine; Narcylen; C2H2; Acetylen; UN 1001; Vinylene
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
  • Vibrational and/or electronic energy levels
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Electron-Impact Ionization Cross Sections (on physics web site)
  • Computational Chemistry Comparison and Benchmark Database
  • Gas Phase Kinetics Database
• Options:
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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)

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Gas phase thermochemistry data

Go To: Top, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, 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:
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Constant pressure heat capacity of gas

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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IR Spectrum

Go To: Top, Gas phase thermochemistry data, Mass spectrum (electron ionization), Gas Chromatography, References, Notes

Data compiled by: Coblentz Society, Inc.

• GAS (50 mmHg DILUTED TO A TOTAL PRESSURE OF 600 mmHg WITH N2); DOW KBr FOREPRISM; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm^-1 resolution

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

• gas

Mass spectrum (electron ionization)

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

Gas Chromatography

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Kovats' RI, non-polar column, isothermal

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Kovats' RI, non-polar column, custom temperature program

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Normal alkane RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, custom temperature program

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References

Go To: Top, Gas phase thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, 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]

Manion, 2002
Manion, J.A., Evaluated Enthalpies of Formation of the Stable Closed Shell C1 and C2 Chlorinated Hydrocarbons, J. Phys. Chem. Ref. Data, 2002, 31, 1, 123-172, https://doi.org/10.1063/1.1420703 . [all data]

Gurvich, Veyts, et al., 1991
Thermodynamic Properties of Individual Substances, 4th edition, Volume 2, Gurvich, L.V.; Veyts, I.V.; Alcock, C.B.;, ed(s)., Hemisphere, New York, 1991. [all data]

Wagman, Kilpatrick, et al., 1945
Wagman, D.D.; Kilpatrick, J.E.; Pitzer, K.S.; Rossini, F.D., Heats, equilibrium constants, and free energies of formation of the acetylene hydrocarbons through the pentynes, to 1,500° K, J. Res. NBS, 1945, 35, 467-496. [all data]

Gurvich, Veyts, et al., 1989
Gurvich, L.V.; Veyts, I.V.; Alcock, C.B., Thermodynamic Properties of Individual Substances, 4th ed.; Vols. 1 and 2, Hemisphere, New York, 1989. [all data]

Hively and Hinton, 1968
Hively, R.A.; Hinton, R.E., Variation of the retention index with temperature on squalane substrates, J. Gas Chromatogr., 1968, 6, 4, 203-217, https://doi.org/10.1093/chromsci/6.4.203 . [all data]

Hoekman, 1993
Hoekman, S.K., Improved gas chromatography procedure for speciated hydrocarbon measurements of vehicle emissions, J. Chromatogr., 1993, 639, 2, 239-253, https://doi.org/10.1016/0021-9673(93)80260-F . [all data]

Supelco, 2012
Supelco, CatalogNo. 24160-U, Petrocol DH Columns. Catalog No. 24160-U, 2012, retrieved from http://www.sigmaaldrich.com/etc/medialib/docs/Supelco/Datasheet/1/w97949.Par.0001.File.tmp/w97949.pdf. [all data]

Zenkevich, 2005
Zenkevich, I.G., Experimentally measured retention indices., 2005. [all data]

Chen and Feng, 2007
Chen, Y.; Feng, C., QSPR study on gas chromatography retention index of some organic pollutants, Comput. Appl. Chem. (China), 2007, 24, 10, 1404-1408. [all data]

Zenkevich and Rodin, 2004
Zenkevich, I.G.; Rodin, A.A., Gas chromatographic identification of some volatile toxic fluorine containing compounds by precalculated retention indices, J. Ecol. Chem. (Rus.), 2004, 13, 1, 22-28. [all data]

Flanagan, Streete, et al., 1997
Flanagan, R.J.; Streete, P.J.; Ramsey, J.D., Volatile Substance Abuse, UNODC Technical Series, No 5, United Nations, Office on Drugs and Crime, Vienna International Centre, PO Box 500, A-1400 Vienna, Austria, 1997, 56, retrieved from http://www.odccp.org/pdf/technical_series₁997-01-01₁.pdf. [all data]

Strete, Ruprah, et al., 1992
Strete, P.J.; Ruprah, M.; Ramsey, J.D.; Flanagan, R.J., Detection and identification of volatile substances by headspace capillary gas chromatography to aid the diagnosis of acute poisoning, Analyst, 1992, 117, 7, 1111-1127, https://doi.org/10.1039/an9921701111 . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, References

• Symbols used in this document:
  

  Cp,gas	Constant pressure heat capacity of gas
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  ΔfH°gas	Enthalpy of formation of gas at standard conditions

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