Citric acid

• Formula: C₆H₈O₇
• Molecular weight: 192.1235
• IUPAC Standard InChI: InChI=1S/C6H8O7/c7-3(8)1-6(13,5(11)12)2-4(9)10/h13H,1-2H2,(H,7,8)(H,9,10)(H,11,12) Copy

  
• IUPAC Standard InChIKey: KRKNYBCHXYNGOX-UHFFFAOYSA-N Copy
• CAS Registry Number: 77-92-9
• Chemical structure:
  This structure is also available as a 2d Mol file
• Other names: 1,2,3-Propanetricarboxylic acid, 2-hydroxy-; Aciletten; Citretten; Citro; 2-Hydroxy-1,2,3-propanetricarboxylic acid; β-Hydroxytricarballylic acid; Anhydrous citric acid; Citric acid, anhydrous; Kyselina citronova; Kyselina 2-hydroxy-1,2,3-propantrikarbonova; 3-Carboxy-3-hydroxypentane-1,5-dioic acid; Chemfill; F 0001 (polycarboxylic acid); Hydrocerol A; NSC 30279; NSC 626579; K-Lyte DS (Salt/Mix); K-Lyte (Salt/Mix); Citraclean (Salt/Mix); K-Lyte/Cl (Salt/Mix)
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Condensed phase thermochemistry data
  • Phase change data
  • Henry's Law data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • References
  • Notes
• Options:
  • Switch to SI units

Data at NIST subscription sites:

• 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.

Condensed phase thermochemistry data

Go To: Top, Phase change data, Henry's Law data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of solid

Phase change data

Go To: Top, Condensed phase thermochemistry data, Henry's Law data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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: Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director

Henry's Law data

Go To: Top, Condensed phase thermochemistry data, Phase change data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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)

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)

IR Spectrum

Go To: Top, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Mass spectrum (electron ionization), UV/Visible spectrum, 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: Coblentz Society, Inc.

Condensed Phase 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

Notice: Except where noted, spectra from this collection were measured on dispersive instruments, often in carefully selected solvents, and hence may differ in detail from measurements on FTIR instruments or in other chemical environments. More information on the manner in which spectra in this collection were collected can be found here.

Notice: Concentration information is not available for this spectrum and, therefore, molar absorptivity values cannot be derived.

Additional Data

Mass spectrum (electron ionization)

Go To: Top, Condensed phase thermochemistry data, Phase change data, Henry's Law data, IR Spectrum, UV/Visible spectrum, 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

UV/Visible spectrum

Go To: Top, Condensed phase thermochemistry data, Phase change data, Henry's Law data, IR Spectrum, 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 by: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

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, Condensed phase thermochemistry data, Phase change data, Henry's Law data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, Notes

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

Wilhoit and Shiao, 1964
Wilhoit, R.C.; Shiao, D., Thermochemistry of biologically important compounds. Heats of combustion of solid organic acids., J. Chem. Eng. Data, 1964, 9, 595-599. [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]

De Kruif, Van Miltenburg, et al., 1982
De Kruif, C.G.; Van Miltenburg, J.C.; Sprenkels, A.J.J.; Stevens, G., Thermodynamic properties of citric acid and the system citric acid-water, Thermochim. Acta, 1982, 58, 341-354. [all data]

Wilhoit and Shiao, 1964, 2
Wilhoit, R.C.; Shiao, D., Thermochemistry of Biologically Important Compounds. Heats of Combustion of Solid Organic Acids, J. Chem. Eng. Data, 1964, 9, 595. [all data]

Perkampus and Braunschweig, 1966
Perkampus, H.-H.; Braunschweig, T.H., UV atlas of organic compounds, 1966, 1, B10/5. [all data]

Notes

Go To: Top, Condensed phase thermochemistry data, Phase change data, Henry's Law data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, References

• Symbols used in this document:
  

  Cp,solid	Constant pressure heat capacity of solid
  S°solid,1 bar	Entropy of solid at standard conditions (1 bar)
  Tfus	Fusion (melting) point
  d(ln(kH))/d(1/T)	Temperature dependence parameter for Henry's Law constant
  k°H	Henry's Law constant at 298.15K
  ΔcH°solid	Enthalpy of combustion of solid at standard conditions
  ΔfH°solid	Enthalpy of formation of solid at standard conditions

• 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.