Sulfuric Acid
- Formula: H2O4S
- Molecular weight: 98.078
- IUPAC Standard InChI: InChI=1S/H2O4S/c1-5(2,3)4/h(H2,1,2,3,4)
- IUPAC Standard InChIKey: QAOWNCQODCNURD-UHFFFAOYSA-N
- CAS Registry Number: 7664-93-9
- 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: H2SO4; Dipping acid; Hydrogen sulfate; Oil of vitriol; Sulphuric acid; Acide sulfurique; Acido solforico; BOV; Matting acid; Nordhausen acid; Schwefelsaeureloesungen; Vitriol brown oil; Vitriol, oil of; Zwavelzuuroplossingen; O2S(OH)2; Battery acid; Electrolyte acid; Spirit of alum; Spirit of vitriol; Dihydrogen sulfate; Mattling acid; UN 1830 (Salt/Mix); UN 1832 (Salt/Mix); UN 2796 (Salt/Mix)
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Gas phase ion energetics 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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
Data compiled as indicated in comments:
B - John E. Bartmess
MM - Michael M. Meot-Ner (Mautner)
LL - Sharon G. Lias and Joel F. Liebman
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| Proton affinity (review) | 167.2 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
| Quantity | Value | Units | Method | Reference | Comment |
| Gas basicity | 159.4 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔfH°(+) ion | 119. ± 5. | kcal/mol | N/A | N/A |
Gas basicity at 298K
| Gas basicity (review) (kcal/mol) | Reference | Comment |
|---|---|---|
| 163. ± 1. | Do, Klein, et al., 1998 | T = T(eff) = 800 - 1250K; H2S; H2CO. ΔGB values from kinetic bracketing were extrapolated to 298 K. ΔSp from ab initio rot. and vib. constants; MM |
| ≥163. | Do, Klein, et al., 1998 | MM |
Protonation entropy at 298K
| Protonation entropy (cal/mol*K) | Reference | Comment |
|---|---|---|
| 1.2 | Do, Klein, et al., 1998 | T = T(eff) = 800 - 1250K; H2S; H2CO. ΔGB values from kinetic bracketing were extrapolated to 298 K. ΔSp from ab initio rot. and vib. constants; MM |
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 12.40 ± 0.05 | EI | Snow and Thomas, 1990 | LL |
Appearance energy determinations
| Ion | AE (eV) | Other Products | Method | Reference | Comment |
|---|---|---|---|---|---|
| HSO3+ | 13.9 ± 0.1 | HO | EI | Snow and Thomas, 1990 | LL |
| H2O+ | 13.2 ± 0.2 | SO3 | EI | Snow and Thomas, 1990 | LL |
| SO2+ | 15.97 ± 0.15 | H2O2 | EI | Snow and Thomas, 1990 | LL |
| SO3+ | 13.8 ± 0.2 | H2O | EI | Snow and Thomas, 1990 | LL |
De-protonation reactions
HO4S- + =
By formula: HO4S- + H+ = H2O4S
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 309.6 ± 5.4 | kcal/mol | D-EA | Wang, Nicholas, et al., 2000 | gas phase; Lit BDE seems too weak. This plus Viggiano, Henchman, et al., 1992 gives BDE=106; B |
| ΔrH° | 309.6 ± 2.6 | kcal/mol | G+TS | Viggiano, Henchman, et al., 1992 | gas phase; B |
| ΔrH° | 316.80 | kcal/mol | Latt | House Jr. and Kemper, 1987 | gas phase; From lattice energy of NH4HSO4, with new PA(NH3); B |
| ΔrH° | <315.40 | kcal/mol | G+TS | Vigiano, Perry, et al., 1980 | gas phase; I- + H2SO4 ->.; B |
| ΔrH° | <313.6 ± 2.0 | kcal/mol | EIAE | Adams, Smith, et al., 1986 | gas phase; From H2SO4 (AP 0eV); B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 302.3 ± 5.5 | kcal/mol | H-TS | Wang, Nicholas, et al., 2000 | gas phase; Lit BDE seems too weak. This plus Viggiano, Henchman, et al., 1992 gives BDE=106; B |
| ΔrG° | 302.3 ± 2.5 | kcal/mol | IMRB | Viggiano, Henchman, et al., 1992 | gas phase; B |
| ΔrG° | <308.00 | kcal/mol | IMRB | Vigiano, Perry, et al., 1980 | gas phase; I- + H2SO4 ->.; B |
| ΔrG° | <306.2 ± 2.3 | kcal/mol | H-TS | Adams, Smith, et al., 1986 | gas phase; From H2SO4 (AP 0eV); B |
References
Go To: Top, Gas phase ion energetics data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G.,
Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update,
J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018
. [all data]
Do, Klein, et al., 1998
Do, K.; Klein, T.P.; Pommering, C.A.; Bachrach, S.M.; Sunderlin, L.S.,
The gas-phase basicity of sulfuric acid,
J. Am. Chem. Soc., 1998, 120, 6093. [all data]
Snow and Thomas, 1990
Snow, K.B.; Thomas, T.F.,
Mass spectrum, ionization potential, and appearance potentials for fragment ions of sulfuric acid vapor,
Int. J. Mass Spectrom. Ion Processes, 1990, 96, 49. [all data]
Wang, Nicholas, et al., 2000
Wang, X.B.; Nicholas, J.B.; Wang, L.S.,
Photoelectron spectroscopy and theoretical calculations of SO4- and HSO4-: Confirmation of high electron affinities of SO4 and HSO4,
J. Phys. Chem. A, 2000, 104, 3, 504-508, https://doi.org/10.1021/jp992726r
. [all data]
Viggiano, Henchman, et al., 1992
Viggiano, A.A.; Henchman, M.J.; Dale, F.; Deakyne, C.A.; Paulson, J.F.,
Gas-Phase Reactions of Weak Bronsted Bases I-, PO3-, HSO4-, FSO3-, and CF3SO3- with Strong Bronsted Acids H2SO4, FSO3H, and CF3SO3H - A Quantitative Study,
J. Am. Chem. Soc., 1992, 114, 11, 4299, https://doi.org/10.1021/ja00037a039
. [all data]
House Jr. and Kemper, 1987
House Jr.; Kemper, K.A.,
Proton Affinities of Sulfate and Bisulfate Ions,
J. Thermal Anal., 1987, 32, 6, 1855, https://doi.org/10.1007/BF01913977
. [all data]
Vigiano, Perry, et al., 1980
Vigiano, A.A.; Perry, R.A.; Albritton, D.L.; Ferguson, E.E.; Fehsenfeld, F.C.,
The role of H2SO4 in stratospheric negative ion chemistry,
J. Geophys. Res., 1980, 85, 4551. [all data]
Adams, Smith, et al., 1986
Adams, N.G.; Smith, D.; Viggiano, A.A.; Paulson, J.F.; Henchman, M.J.,
Dissociative attachment reactions of electron with strong acid molecules,
J. Chem. Phys., 1986, 84, 6728. [all data]
Notes
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance 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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