Ammonium hydrogen oxalate hemihydrate
- Formula: C4H10N2O8·H2O
- Molecular weight: 232.1461
- IUPAC Standard InChI: InChI=1S/2C2H2O4.2H3N.H2O/c2*3-1(4)2(5)6;;;/h2*(H,3,4)(H,5,6);2*1H3;1H2
- IUPAC Standard InChIKey: LRFVZPMSSZVHGG-UHFFFAOYSA-N
- CAS Registry Number: 37541-72-3
- Chemical structure:
This structure is also available as a 2d Mol file - Permanent link for this species. Use this link for bookmarking this species for future reference.
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Condensed phase thermochemistry data
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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: Eugene S. Domalski and Elizabeth D. Hearing
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| S°solid,1 bar | 189.24 | J/mol*K | N/A | Fukai, Matsuo, et al., 1989 | |
| S°solid,1 bar | 189.24 | J/mol*K | N/A | Fukai, Matsuo, et al., 1989 |
Constant pressure heat capacity of solid
| Cp,solid (J/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 166.91 | 298.15 | Fukai, Matsuo, et al., 1989 | T = 13 to 300 K. |
| 166.91 | 298.15 | Fukai, Matsuo, et al., 1989 | T = 13 to 300 K. |
Phase change data
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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: Eugene S. Domalski and Elizabeth D. Hearing
Enthalpy of phase transition
| ΔHtrs (kJ/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
|---|---|---|---|---|---|
| 0.730 | 145.4 | crystaline, II | crystaline, I | Fukai, Matsuo, et al., 1990 | |
| 0.00037 | 145.4 | crystaline, II | crystaline, I | Fukai, Matsuo, et al., 1989 | |
| 0.00037 | 145.4 | crystaline, II | crystaline, I | Fukai, Matsuo, et al., 1989 |
Entropy of phase transition
| ΔStrs (J/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
|---|---|---|---|---|---|
| 6.01 | 145.4 | crystaline, II | crystaline, I | Fukai, Matsuo, et al., 1990 | |
| 3.01 | 145.4 | crystaline, II, Order | crystaline, I, disorder transition | Fukai, Matsuo, et al., 1989 | |
| 3.01 | 145.4 | crystaline, II, Order | crystaline, I, disorder transition | Fukai, Matsuo, et al., 1989 |
References
Go To: Top, Condensed phase thermochemistry data, Phase change data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Fukai, Matsuo, et al., 1989
Fukai, M.; Matsuo, T.; Suga, H.,
Calorimetric study of phase transitions in ammonium hydrogen oxalate hemihydrate and its deuterated compound,
J. Phys. Chem. Solids, 1989, 50, 743-751. [all data]
Fukai, Matsuo, et al., 1990
Fukai, M.; Matsuo, T.; Suga, H.,
Low temperature heat capacities of ammonium hydrogen oxalate hemihydrate and its deuterate analogue,
Ferroelectrics, 1990, 108, 367-372. [all data]
Notes
Go To: Top, Condensed phase thermochemistry data, Phase change data, 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) ΔHtrs Enthalpy of phase transition ΔStrs Entropy of phase transition - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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