Sulfuric Acid
- Formula: H2O4S
- Molecular weight: 98.078
- 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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Henry's Law data
Go To: Top, Gas phase ion energetics data, 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)
kH(T) = k°H exp(d(ln(kH))/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(kH))/d(1/T) = Temperature dependence constant (K)
k°H (mol/(kg*bar)) | d(ln(kH))/d(1/T) (K) | Method | Reference | Comment |
---|---|---|---|---|
1.×10+11 | M | N/A | Value derived from partial pressure of H2SO4 over a concentrated solution. This can only be considered an order-of-magnitude approximation. The solubility at lower aqueous-phase concentrations should be larger. | |
5.×10+14 | M | N/A | Value derived from partial pressure of H2SO4 over a concentrated solution. This can only be considered an order-of-magnitude approximation. The solubility at lower aqueous-phase concentrations should be larger. |
Gas phase ion energetics data
Go To: Top, Henry's Law data, 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) | 699.4 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 666.9 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
ΔfH°(+) ion | 500. ± 20. | kJ/mol | N/A | N/A |
Gas basicity at 298K
Gas basicity (review) (kJ/mol) | Reference | Comment |
---|---|---|
683. ± 5. | 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 |
≥680. | Do, Klein, et al., 1998 | MM |
Protonation entropy at 298K
Protonation entropy (J/mol*K) | Reference | Comment |
---|---|---|
4.9 | 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° | 1295. ± 23. | kJ/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° | 1295. ± 11. | kJ/mol | G+TS | Viggiano, Henchman, et al., 1992 | gas phase; B |
ΔrH° | 1325.5 | kJ/mol | Latt | House Jr. and Kemper, 1987 | gas phase; From lattice energy of NH4HSO4, with new PA(NH3); B |
ΔrH° | <1319.6 | kJ/mol | G+TS | Vigiano, Perry, et al., 1980 | gas phase; I- + H2SO4 ->.; B |
ΔrH° | <1312. ± 8.4 | kJ/mol | EIAE | Adams, Smith, et al., 1986 | gas phase; From H2SO4 (AP 0eV); B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1265. ± 23. | kJ/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° | 1265. ± 10. | kJ/mol | IMRB | Viggiano, Henchman, et al., 1992 | gas phase; B |
ΔrG° | <1288.7 | kJ/mol | IMRB | Vigiano, Perry, et al., 1980 | gas phase; I- + H2SO4 ->.; B |
ΔrG° | <1281. ± 9.6 | kJ/mol | H-TS | Adams, Smith, et al., 1986 | gas phase; From H2SO4 (AP 0eV); B |
References
Go To: Top, Henry's Law data, 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, Henry's Law data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy d(ln(kH))/d(1/T) Temperature dependence parameter for Henry's Law constant k°H Henry's Law constant at 298.15K 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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