Compound Information 

Name: ethanedioic acid
Formula: C2H2O4
Molar Mass: 90.034
Additional Names: oxalic acid
Image of ethanedioic acid

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Property Availability 

For this compound, WTT contains critically evaluated recommendations for:
(Please note that if more than 50 points are used for regression, only the 50 most-constraining points are reported)

  • Critical temperature (Liquid and Gas)
    • Critical pressure (Liquid and Gas)
      • Phase boundary pressure
        • Phase boundary pressure (Metastable crystal in equilibrium with Gas) as a function of Temperature
          Temperature from 310.681 K to 324.876 K
          10 experimental data points
        • Phase boundary pressure (Crystal 1 in equilibrium with Gas) as a function of Temperature
          Temperature from 310.681 K to 378.405 K
          27 experimental data points
      • Critical density (Liquid and Gas)
        • Density (Liquid in equilibrium with Gas) as a function of Temperature
          Temperature from 250 K to 862 K
          • Heat capacity at saturation pressure (Crystal 1 in equilibrium with Gas) as a function of Temperature
            Temperature from 0.0003 K to 319.988 K
            50 experimental data points
            • Heat capacity at constant pressure (Ideal Gas) as a function of Temperature
              Temperature from 50 K to 1500 K
              • Enthalpy
                • Enthalpy (Crystal 1 in equilibrium with Gas) as a function of Temperature
                  Temperature from 0.0003 K to 319.988 K
                  39 experimental data points
                • Enthalpy (Ideal Gas) as a function of Temperature
                  Temperature from 50 K to 1500 K
              • Entropy
                • Entropy (Crystal 1 in equilibrium with Gas) as a function of Temperature
                  Temperature from 0.0003 K to 319.988 K
                  39 experimental data points
                • Entropy (Ideal Gas) as a function of Temperature and Pressure
                  Temperature from 50 K to 1500 K
              • Enthalpy of formation (Crystal)
                1 experimental data points

                About WTT 

                NIST/TRC Web Thermo Tables (WTT)
                NIST Standard Reference Subscription Database 3 - Professional Edition
                Version 2-2012-1-Pro

                This web application provides access to a collection of critically evaluated thermodynamic property data for pure compounds with a primary focus on organics. These data were generated through dynamic data analysis, as implemented in the NIST ThermoData Engine software package [1, 2, 3, 4, 5, 6]. Some critically evaluated data from the historical TRC Thermodynamic Tables archive [7, 8] are included, also. As of May 2012, the Professional Edition contains information on 28432 compounds and total of 531486 evaluated data points. The properties covered by both versions (32 total) are described in Properties and Implemented Models.

                Developed by Kenneth Kroenlein, Chris D. Muzny, Andrei F. Kazakov, Vladimir Diky, Robert D. Chirico, Joseph W. Magee, Ilmutdin Abdulagatov and Michael Frenkel.

                Thermodynamics Research Center (TRC)
                Thermophysical Properties Division
                National Institute of Standards and Technology
                Boulder CO 80305-3337

                Questions and comments should be addressed to Dr. Michael Frenkel .

                DISCLAIMER: 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 methods and data contained therein have been selected on the basis of sound scientific judgement. 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 program and database.

                Distributed by:
                Standard Reference Data Program
                National Institute of Standards and Technology
                Gaithersburg MD 20899

                Compound Information
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