HCO2 anion
- Formula: CHO2-
- Molecular weight: 45.0180
- IUPAC Standard InChI: InChI=1S/CH2O2/c2-1-3/h1H,(H,2,3)/p-1
- IUPAC Standard InChIKey: BDAGIHXWWSANSR-UHFFFAOYSA-M
- CAS Registry Number: 71-47-6
- Chemical structure:
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Reaction thermochemistry data
Go To: Top, 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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.
Individual Reactions
+
=
By formula: CHO2- + H+ = CH2O2
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 1449. ± 5.0 | kJ/mol | D-EA | Kim, Bradforth, et al., 1995 | gas phase; dHacid(0K) = 344.67±0.62 kcal/mol; B |
| ΔrH° | 1445. ± 9.2 | kJ/mol | G+TS | Caldwell, Renneboog, et al., 1989 | gas phase; B |
| ΔrH° | 1445. ± 9.2 | kJ/mol | G+TS | Fujio, McIver, et al., 1981 | gas phase; value altered from reference due to change in acidity scale; B |
| ΔrH° | 1444. ± 12. | kJ/mol | G+TS | Cumming and Kebarle, 1978 | gas phase; B |
| ΔrH° | 1423. ± 19. | kJ/mol | EIAE | Muftakhov, Vasil'ev, et al., 1999 | gas phase; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 1419. ± 6.3 | kJ/mol | H-TS | Kim, Bradforth, et al., 1995 | gas phase; dHacid(0K) = 344.67±0.62 kcal/mol; B |
| ΔrG° | 1415. ± 8.4 | kJ/mol | IMRE | Caldwell, Renneboog, et al., 1989 | gas phase; B |
| ΔrG° | 1416. ± 8.4 | kJ/mol | IMRE | Fujio, McIver, et al., 1981 | gas phase; value altered from reference due to change in acidity scale; B |
| ΔrG° | 1415. ± 8.4 | kJ/mol | IMRE | Cumming and Kebarle, 1978 | gas phase; B |
+
= (
•
)
By formula: CHO2- + H2O = (CHO2- • H2O)
Bond type: Hydrogen bond (negative ion to hydride)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 66.9 ± 4.2 | kJ/mol | TDAs | Meot-Ner and Sieck, 1986 | gas phase; B,M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 96.2 | J/mol*K | PHPMS | Meot-Ner and Sieck, 1986 | gas phase; M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 38. ± 6.7 | kJ/mol | TDAs | Meot-Ner and Sieck, 1986 | gas phase; B |
| ΔrG° | 35.1 ± 0.84 | kJ/mol | N/A | Viidanoja, Reiner, et al., 2000 | gas phase; B |
| ΔrG° | 38.5 ± 1.3 | kJ/mol | TDAs | Blades, Klassen, et al., 1995 | gas phase; T: 293 K. ΔSaff approx. 24 cal/mol-K; B,M |
+
= (
•
)
By formula: CHO2- + CHN = (CHO2- • CHN)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 92.0 | kJ/mol | PHPMS | Meot-ner, 1988 | gas phase; M,B,M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 92. | J/mol*K | N/A | Meot-ner, Cybulski, et al., 1988 | gas phase; Entropy change calculated or estimated; M |
| ΔrS° | 89.5 | J/mol*K | PHPMS | Meot-ner, 1988 | gas phase; M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 65.3 ± 6.7 | kJ/mol | TDAs | Meot-ner, Cybulski, et al., 1988 | gas phase; Entropy of 22.0 eu assumed.; B |
Free energy of reaction
| ΔrG° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 49.4 | 473. | PHPMS | Meot-ner, Cybulski, et al., 1988 | gas phase; Entropy change calculated or estimated; M |
( •
) +
= (
• 2
)
By formula: (CHO2- • CHN) + CHN = (CHO2- • 2CHN)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 74.5 | kJ/mol | PHPMS | Meot-ner, 1988 | gas phase; M,B,M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 92. | J/mol*K | N/A | Meot-ner, Cybulski, et al., 1988 | gas phase; Entropy change calculated or estimated; M |
| ΔrS° | 98.7 | J/mol*K | PHPMS | Meot-ner, 1988 | gas phase; M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 44.77 | kJ/mol | TDAs | Meot-ner, Cybulski, et al., 1988 | gas phase; Entropy estimated; B |
Free energy of reaction
| ΔrG° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 40. | 350. | PHPMS | Meot-ner, Cybulski, et al., 1988 | gas phase; Entropy change calculated or estimated; M |
( • 2
) +
= (
• 3
)
By formula: (CHO2- • 2H2O) + H2O = (CHO2- • 3H2O)
Bond type: Hydrogen bond (negative ion to hydride)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 50.6 ± 6.3 | kJ/mol | TDAs | Blades, Klassen, et al., 1995 | gas phase; T: 293 K. ΔSaff approx. 24 cal/mol-K; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 21.3 ± 1.3 | kJ/mol | TDAs | Blades, Klassen, et al., 1995 | gas phase; T: 293 K. ΔSaff approx. 24 cal/mol-K; B,M |
| ΔrG° | 21.8 ± 0.84 | kJ/mol | N/A | Viidanoja, Reiner, et al., 2000 | gas phase; B |
( •
) +
= (
• 2
)
By formula: (CHO2- • H2O) + H2O = (CHO2- • 2H2O)
Bond type: Hydrogen bond (negative ion to hydride)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 57.7 ± 6.3 | kJ/mol | TDAs | Blades, Klassen, et al., 1995 | gas phase; T: 293 K. ΔSaff approx. 24 cal/mol-K; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 28.5 ± 1.3 | kJ/mol | TDAs | Blades, Klassen, et al., 1995 | gas phase; T: 293 K. ΔSaff approx. 24 cal/mol-K; B,M |
| ΔrG° | 28.9 ± 0.84 | kJ/mol | N/A | Viidanoja, Reiner, et al., 2000 | gas phase; B |
+
= (
•
)
By formula: CHO2- + CH2O2 = (CHO2- • CH2O2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 154. ± 4.2 | kJ/mol | N/A | Meot-Ner and Sieck, 1986 | gas phase; B,M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 164. | J/mol*K | PHPMS | Meot-Ner and Sieck, 1986 | gas phase; large ΔrH, ΔrS,; cyclic structure? pyrolysis?; M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 105. ± 6.7 | kJ/mol | TDAs | Meot-Ner and Sieck, 1986 | gas phase; B |
( • 4
) +
= (
• 5
)
By formula: (CHO2- • 4CH2O2) + CH2O2 = (CHO2- • 5CH2O2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 42.3 ± 8.4 | kJ/mol | N/A | Luczynski, Wlodek, et al., 1978 | gas phase; Buffer gas H2. There may be appreciable fractionation of neutral gases: Williamson, Knighton, et al., 1996; B,M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 50. | J/mol*K | HPMS | Luczynski, Wlodek, et al., 1978 | gas phase; Entropy change is questionable; M |
( • 3
) +
= (
• 4
)
By formula: (CHO2- • 3CH2O2) + CH2O2 = (CHO2- • 4CH2O2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 59.4 ± 8.8 | kJ/mol | N/A | Luczynski, Wlodek, et al., 1978 | gas phase; Buffer gas H2. There may be appreciable fractionation of neutral gases: Williamson, Knighton, et al., 1996; B,M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 90.0 | J/mol*K | HPMS | Luczynski, Wlodek, et al., 1978 | gas phase; M |
( • 2
) +
= (
• 3
)
By formula: (CHO2- • 2CH2O2) + CH2O2 = (CHO2- • 3CH2O2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 84. ± 11. | kJ/mol | N/A | Luczynski, Wlodek, et al., 1978 | gas phase; Buffer gas H2. There may be appreciable fractionation of neutral gases: Williamson, Knighton, et al., 1996; B,M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 130. | J/mol*K | HPMS | Luczynski, Wlodek, et al., 1978 | gas phase; M |
( •
) +
= (
• 2
)
By formula: (CHO2- • CH2O2) + CH2O2 = (CHO2- • 2CH2O2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 109. ± 13. | kJ/mol | N/A | Luczynski, Wlodek, et al., 1978 | gas phase; Buffer gas H2. There may be appreciable fractionation of neutral gases: Williamson, Knighton, et al., 1996; B,M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 140. | J/mol*K | HPMS | Luczynski, Wlodek, et al., 1978 | gas phase; M |
+
= (
•
)
By formula: CHO2- + CH4O = (CHO2- • CH4O)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 73.6 ± 4.2 | kJ/mol | N/A | Meot-Ner and Sieck, 1986 | gas phase; B,M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 98.7 | J/mol*K | PHPMS | Meot-Ner and Sieck, 1986 | gas phase; M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 43.9 ± 6.7 | kJ/mol | TDAs | Meot-Ner and Sieck, 1986 | gas phase; B |
( • 4294967295
) +
=
By formula: (CHO2- • 4294967295CO2) + CO2 = CHO2-
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 216. ± 9.6 | kJ/mol | N/A | Caldwell, Renneboog, et al., 1989 | gas phase; B |
References
Go To: Top, Reaction thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Kim, Bradforth, et al., 1995
Kim, E.H.; Bradforth, S.E.; Arnold, D.W.; Metz, R.B.; Neumark, D.M.,
Study of HCO2 and DCO2 by Negative Ion Photoelectron Spectroscopy,
J. Chem. Phys., 1995, 103, 18, 7801, https://doi.org/10.1063/1.470196
. [all data]
Caldwell, Renneboog, et al., 1989
Caldwell, G.; Renneboog, R.; Kebarle, P.,
Gas Phase Acidities of Aliphatic Carboxylic Acids, Based on Measurements of Proton Transfer Equilibria,
Can. J. Chem., 1989, 67, 4, 661, https://doi.org/10.1139/v89-092
. [all data]
Fujio, McIver, et al., 1981
Fujio, M.; McIver, R.T., Jr.; Taft, R.W.,
Effects on the acidities of phenols from specific substituent-solvent interactions. Inherent substituent parameters from gas phase acidities,
J. Am. Chem. Soc., 1981, 103, 4017. [all data]
Cumming and Kebarle, 1978
Cumming, J.B.; Kebarle, P.,
Summary of gas phase measurements involving acids AH. Entropy changes in proton transfer reactions involving negative ions. Bond dissociation energies D(A-H) and electron affinities EA(A),
Can. J. Chem., 1978, 56, 1. [all data]
Muftakhov, Vasil'ev, et al., 1999
Muftakhov, M.V.; Vasil'ev, Y.V.; Mazunov, V.A.,
Determination of electron affinity of carbonyl radicals by means of negative ion mass spectrometry,
Rapid Commun. Mass Spectrom., 1999, 13, 12, 1104-1108, https://doi.org/10.1002/(SICI)1097-0231(19990630)13:12<1104::AID-RCM619>3.0.CO;2-C
. [all data]
Meot-Ner and Sieck, 1986
Meot-Ner, M.; Sieck, L.W.,
The ionic hydrogen bond and ion solvation. 5. OH...O- bonds. Gas phase solvation and clustering of alkoxide and carboxylate anions,
J. Am. Chem. Soc., 1986, 108, 7525. [all data]
Viidanoja, Reiner, et al., 2000
Viidanoja, J.; Reiner, T.; Kiendler, A.; Grimm, F.; Arnold, F.,
Laboratory investigations of negative ion molecule reactions of propionic, butyric, glyoxylic, pyruvic, and pinonic acids,
Int. J. Mass Spectrom., 2000, 194, 1, 53-68, https://doi.org/10.1016/S1387-3806(99)00172-4
. [all data]
Blades, Klassen, et al., 1995
Blades, A.T.; Klassen, J.S.; Kebarle, P.,
Free Energies of Hydration in the Gas Phase on the Anions of Some Oxo Acids of C, N, S, P, Cl and I,
J. Am. Chem. Soc., 1995, 117, 42, 10563, https://doi.org/10.1021/ja00147a019
. [all data]
Meot-ner, 1988
Meot-ner, M.,
Ionic Hydrogen Bond and Ion Solvation. 6. Interaction Energies of the Acetate Ion with Organic Molecules. Comparison of CH3COO- with Cl-, CN-, and SH-,
J. Am. Chem. Soc., 1988, 110, 12, 3854, https://doi.org/10.1021/ja00220a022
. [all data]
Meot-ner, Cybulski, et al., 1988
Meot-ner, M.; Cybulski, S.M.; Scheiner, S.; Liebman, J.F.,
Is CN- Significantly Anisotropic? Comparison of CN- vs. Cl-: Clustering with HCN and Condensed Phase Thermochemistry,
J. Phys. Chem., 1988, 92, 10, 2738, https://doi.org/10.1021/j100321a009
. [all data]
Luczynski, Wlodek, et al., 1978
Luczynski, Z.; Wlodek, S.; Wincel, H.,
Stabilities of HCOO-.(HCOOH)n and Cl-.(HCOOH)n clusters,
Int. J. Mass Spectrom. Ion Phys., 1978, 26, 103. [all data]
Williamson, Knighton, et al., 1996
Williamson, D.H.; Knighton, W.B.; Grimsrud, E.P.,
Pulsed High Pressure Mass Spectrometry with Near-Viscous Flow Ion Sampling,
Int. J. Mass Spectrom. Ion Proc., 1996, 154, 1-2, 15, https://doi.org/10.1016/0168-1176(96)04372-8
. [all data]
Notes
Go To: Top, Reaction thermochemistry data, References
- Symbols used in this document:
T Temperature ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔrS° Entropy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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