Isobutane

• Formula: C₄H₁₀
• Molecular weight: 58.1222
• IUPAC Standard InChI: InChI=1S/C4H10/c1-4(2)3/h4H,1-3H3 Copy

  
• IUPAC Standard InChIKey: NNPPMTNAJDCUHE-UHFFFAOYSA-N Copy
• CAS Registry Number: 75-28-5
• 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: Propane, 2-methyl-; Trimethylmethane; 1,1-Dimethylethane; 2-Methylpropane; iso-C4H10; i-Butane; UN 1969; R 600a; tert-Butane; A 31; Methylpropane; A 31 (hydrocarbon)
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• Information on this page:
  • Gas phase ion energetics data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • Fluid Properties
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Gas Phase Kinetics Database
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Gas phase ion energetics data

Go To: Top, Ion clustering data, 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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
LL - Sharon G. Lias and Joel F. Liebman
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

Appearance energy determinations

De-protonation reactions

C₄H₉^- +  =

By formula: C₄H₉^- + H⁺ = C₄H₁₀

C₄H₉^- +  =

By formula: C₄H₉^- + H⁺ = C₄H₁₀

IR Spectrum

Go To: Top, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), Gas Chromatography, References, Notes

Data compiled by: Coblentz Society, Inc.

• GAS (100 mmHg, N2 ADDED, TOTAL PRESSURE 600 mmHg) NOTE: High partial pressure may produce unreliable values in the range of 2500 to 3400 cm-1; see scan of original spectrum.; DOW KBr FOREPRISM-GRATING; DIGITIZED BY COBLENTZ SOCIETY (BATCH II) FROM HARD COPY; 2 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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Kovats' RI, polar column, isothermal

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Van Den Dool and Kratz RI, non-polar column, temperature ramp

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Van Den Dool and Kratz RI, non-polar column, custom temperature program

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Normal alkane RI, non-polar column, isothermal

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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 ion energetics data, Ion clustering 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.

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Bredael, 1982
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Lulova, N.I.; Leont'eva, S.A.; Timofeeva, A.N., Gas-chromatographic method of determination of individual hydrocarbons in catalytic cracking gasolines in Proceedings of All-Union Research Institute on Oil Processes. Vol.18, All-Union Research Institute on Oil Processes, Moscow, 1976, 30-53. [all data]

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Notes

Go To: Top, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, References

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  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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