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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Reaction thermochemistry data

Go To: Top, References, Notes

Data compiled as indicated in comments:
B - John E. Bartmess
MS - José A. Martinho Simões
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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

HO₄S^- + = Sulfuric Acid

By formula: HO₄S^- + H⁺ = H₂O₄S

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	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
Δ_rH°	1295. ± 11.	kJ/mol	G+TS	Viggiano, Henchman, et al., 1992	gas phase; B
Δ_rH°	1325.5	kJ/mol	Latt	House Jr. and Kemper, 1987	gas phase; From lattice energy of NH4HSO4, with new PA(NH3); B
Δ_rH°	<1319.6	kJ/mol	G+TS	Vigiano, Perry, et al., 1980	gas phase; I^- + H₂SO₄ ->.; B
Δ_rH°	<1312. ± 8.4	kJ/mol	EIAE	Adams, Smith, et al., 1986	gas phase; From H₂SO₄ (AP 0eV); B
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	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
Δ_rG°	1265. ± 10.	kJ/mol	IMRB	Viggiano, Henchman, et al., 1992	gas phase; B
Δ_rG°	<1288.7	kJ/mol	IMRB	Vigiano, Perry, et al., 1980	gas phase; I^- + H₂SO₄ ->.; B
Δ_rG°	<1281. ± 9.6	kJ/mol	H-TS	Adams, Smith, et al., 1986	gas phase; From H₂SO₄ (AP 0eV); B

C₂H₅NaO (cr) + 0.5( Sulfuric Acid • 1100) (solution) = (solution) + 0.5 (solution)

By formula: C₂H₅NaO (cr) + 0.5(H₂O₄S • 1100H₂O) (solution) = C₂H₆O (solution) + 0.5Na₂O₄S (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-118.4 ± 3.8	kJ/mol	RSC	Blanchard, Joly, et al., 1974	solvent: Sulphuric acid aqueous solution; The reaction enthalpy relies on -10.6 kJ/mol for the enthalpy of solution of EtOH(l) and on 9.97±0.04 for the enthalpy of solution of Na2SO4(cr) Blanchard, Joly, et al., 1974. A value of -490.8 ± 5.9 kJ/mol was derived in Blanchard, Joly, et al., 1974 for the enthalpy of formation. However, this value is affected by a calculation error. Also, the authors have not accounted for the acid dilution (this correction could not be made in the present database, due to lack of information). These problems were also noted in the data compilations Tel'noi and Rabinovich, 1980 and Wagman, Evans W.H., et al., 1982, where the values quoted for the enthalpy of formation, which rely on the experimental data reported in Blanchard, Joly, et al., 1974, are -410.0 ± 4.2 kJ/mol and -413.8 kJ/mol, respectively. See also comments in Liebman, Martinho Simões, et al., 1995; MS

(HO₄S^- • 2 Sulfuric Acid ) + HO₃S = (HO₄S^- • HO₃S • 2)

By formula: (HO₄S^- • 2H₂O₄S) + HO₃S = (HO₄S^- • HO₃S • 2H₂O₄S)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	87.9	kJ/mol	ATM	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M
Δ_rH°	75.	kJ/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated, DG>, Δ_rH>; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	100.	J/mol*K	N/A	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M
Δ_rS°	100.	J/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated, DG>, Δ_rH>; M

Free energy of reaction

Δ_rG° (kJ/mol)	T (K)	Method	Reference	Comment
61.9	250.	ATM	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M
50.	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated, DG>, Δ_rH>; M

(HO₄S^- • 2 Sulfuric Acid ) + = (HO₄S^- • 3)

By formula: (HO₄S^- • 2H₂O₄S) + H₂O₄S = (HO₄S^- • 3H₂O₄S)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	87.0	kJ/mol	ATM	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M
Δ_rH°	82.8	kJ/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	100.	J/mol*K	N/A	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M
Δ_rS°	100.	J/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kJ/mol)	T (K)	Method	Reference	Comment
61.1	250.	ATM	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M
59.	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

(HO₄S^- • • 3 Sulfuric Acid ) + = (HO₄S^- • 2 • 3)

By formula: (HO₄S^- • H₂O • 3H₂O₄S) + H₂O = (HO₄S^- • 2H₂O • 3H₂O₄S)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	54.4	kJ/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	100.	J/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kJ/mol)	T (K)	Method	Reference	Comment
30.	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

(H₂O₄S^- • Sulfuric Acid ) + HO₃S = (H₂O₄S^- • HO₃S • )

By formula: (H₂O₄S^- • H₂O₄S) + HO₃S = (H₂O₄S^- • HO₃S • H₂O₄S)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	92.5	kJ/mol	ATM	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	100.	J/mol*K	N/A	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kJ/mol)	T (K)	Method	Reference	Comment
66.5	250.	ATM	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M

(HO₄S^- • 2 Sulfuric Acid ) + = (HO₄S^- • • 2)

By formula: (HO₄S^- • 2H₂O₄S) + HNO₃ = (HO₄S^- • HNO₃ • 2H₂O₄S)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	66.5	kJ/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	100.	J/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kJ/mol)	T (K)	Method	Reference	Comment
43.1	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

(HO₄S^- • 3 Sulfuric Acid ) + = (HO₄S^- • • 3)

By formula: (HO₄S^- • 3H₂O₄S) + HNO₃ = (HO₄S^- • HNO₃ • 3H₂O₄S)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	70.7	kJ/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	100.	J/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kJ/mol)	T (K)	Method	Reference	Comment
46.4	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

(HO₄S^- • 2 Sulfuric Acid ) + = (HO₄S^- • • 2)

By formula: (HO₄S^- • 2H₂O₄S) + H₂O = (HO₄S^- • H₂O • 2H₂O₄S)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	50.6	kJ/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	100.	J/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kJ/mol)	T (K)	Method	Reference	Comment
26.	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

(HO₄S^- • 3 Sulfuric Acid ) + = (HO₄S^- • • 3)

By formula: (HO₄S^- • 3H₂O₄S) + H₂O = (HO₄S^- • H₂O • 3H₂O₄S)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	57.7	kJ/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	100.	J/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kJ/mol)	T (K)	Method	Reference	Comment
33.	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

(HO₄S^- • 4 Sulfuric Acid ) + = (HO₄S^- • • 4)

By formula: (HO₄S^- • 4H₂O₄S) + H₂O = (HO₄S^- • H₂O • 4H₂O₄S)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	58.2	kJ/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	100.	J/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kJ/mol)	T (K)	Method	Reference	Comment
34.	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

(HO₄S^- • Sulfuric Acid ) + = (HO₄S^- • 2)

By formula: (HO₄S^- • H₂O₄S) + H₂O₄S = (HO₄S^- • 2H₂O₄S)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	92.0	kJ/mol	ATM	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	100.	J/mol*K	N/A	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kJ/mol)	T (K)	Method	Reference	Comment
66.1	250.	ATM	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M

(HO₄S^- • 3 Sulfuric Acid ) + = (HO₄S^- • 4)

By formula: (HO₄S^- • 3H₂O₄S) + H₂O₄S = (HO₄S^- • 4H₂O₄S)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	77.4	kJ/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	100.	J/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kJ/mol)	T (K)	Method	Reference	Comment
54.	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

(HO₄S^- • 4 Sulfuric Acid ) + = (HO₄S^- • 5)

By formula: (HO₄S^- • 4H₂O₄S) + H₂O₄S = (HO₄S^- • 5H₂O₄S)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	79.1	kJ/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	100.	J/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kJ/mol)	T (K)	Method	Reference	Comment
54.	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

C₂H₅LiO (cr) + 0.5( Sulfuric Acid • 1100) (solution) = 0.5Li₂O₄S (solution) + (solution)

By formula: C₂H₅LiO (cr) + 0.5(H₂O₄S • 1100H₂O) (solution) = 0.5Li₂O₄S (solution) + C₂H₆O (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-113.6 ± 1.3	kJ/mol	RSC	Blanchard, Joly, et al., 1974	solvent: Sulphuric acid aqueous solution; The reaction enthalpy relies on -10.6 kJ/mol for the enthalpy of solution of EtOH(l) and on -17.5±0.3 for the enthalpy of solution of Li2SO4(cr) Blanchard, Joly, et al., 1974.; MS

C₂H₅KO (cr) + 0.5( Sulfuric Acid • 1100) (solution) = (solution) + 0.5K₂O₄S (solution)

By formula: C₂H₅KO (cr) + 0.5(H₂O₄S • 1100H₂O) (solution) = C₂H₆O (solution) + 0.5K₂O₄S (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-132.3 ± 2.9	kJ/mol	RSC	Blanchard, Joly, et al., 1974	solvent: Sulphuric acid aqueous solution; The reaction enthalpy relies on -10.6 kJ/mol for the enthalpy of solution of EtOH(l) and on 35.1±0.1 for the enthalpy of solution of K2SO4(cr) Blanchard, Joly, et al., 1974.; MS

(l) + ( Sulfuric Acid • 100) (solution) = 2 (g) + ( • 100) (solution)

By formula: C₂H₆Zn (l) + (H₂O₄S • 100H₂O) (solution) = 2CH₄ (g) + (O₄SZn • 100H₂O) (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-341.8 ± 0.8	kJ/mol	RSC	Carson, Hartley, et al., 1949	Please also see Pedley and Rylance, 1977 and Cox and Pilcher, 1970.; MS

(l) + ( Sulfuric Acid • 100) (solution) = 2 (g) + ( • 100) (solution)

By formula: C₄H₁₀Zn (l) + (H₂O₄S • 100H₂O) (solution) = 2C₂H₆ (g) + (O₄SZn • 100H₂O) (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-354.4 ± 4.2	kJ/mol	RSC	Carson, Hartley, et al., 1949	Please also see Pedley and Rylance, 1977 and Cox and Pilcher, 1970.; MS

+ Sulfuric Acid = C₁₂H₂₆O₃S +

By formula: C₁₂H₂₆ + H₂O₄S = C₁₂H₂₆O₃S + H₂O

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	290. ± 17.	kJ/mol	Cm	Roth and Rist-Schumacher, 1944	liquid phase; ALS

+ Sulfuric Acid =

By formula: C₃H₆ + H₂O₄S = isopropyl hydrogen sulphate

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-38. ± 0.8	kJ/mol	Eqk	Entelis, Korovina, et al., 1960	liquid phase; ALS

References

Go To: Top, Reaction thermochemistry data, Notes

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]

Blanchard, Joly, et al., 1974
Blanchard, J.M.; Joly, R.D.; Lettoffe, J.M.; Perachon, G.; Thourey, J., J. Chim. Phys. Phys.-Chim. Biol., 1974, 71, 472. [all data]

Tel'noi and Rabinovich, 1980
Tel'noi, V.I.; Rabinovich, I.B., Russ. Chem. Rev., 1980, 49, 603. [all data]

Wagman, Evans W.H., et al., 1982
Wagman, D.D.; Evans W.H.; Parker, V.B.; Schumm, R.H.; Halow, I.; Bailey, S.M.; Churney, K.L.; Nuttall, R.L., The NBS Tables of Chemical Thermodynamic Properties; J. Phys. Chem. Ref. Data, 1982, 11, Suppl. 2. [all data]

Liebman, Martinho Simões, et al., 1995
Liebman, J.F.; Martinho Simões, J.A.; Slayden, S.W., In Lithium Chemistry: A Theoretical and Experimental Overview Wiley: New York, Sapse, A.-M.; Schleyer, P. von Ragué, ed(s)., 1995. [all data]

Arnold and Qiu, 1984
Arnold, F.; Qiu, S., Upper Stratosphere Negative Ion Composition Measurements and Infrared Trace Gas Abundances, Planet. Space Sci., 1984, 32, 2, 169, https://doi.org/10.1016/0032-0633(84)90151-X . [all data]

Arnold, Viggiano, et al., 1982
Arnold, F.; Viggiano, A.A.; Schlager, H., Implications for Trace Gases and Aerosols of Large Negative Ions Clusters in the Stratosphere, Nature, 1982, 297, 5865, 371, https://doi.org/10.1038/297371a0 . [all data]

Carson, Hartley, et al., 1949
Carson, A.S.; Hartley, K.; Skinner, H.A., Thermochemistry of metal alkyls. Part II.?The bond dissociation energies of some Zn?C and Cd?C bonds, and of Et?I., Trans. Faraday Soc., 1949, 45, 1159, https://doi.org/10.1039/tf9494501159 . [all data]

Pedley and Rylance, 1977
Pedley, J.B.; Rylance, J., Computer Analysed Thermochemical Data: Organic and Organometallic Compounds, University of Sussex, Brigton, 1977. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds in Academic Press, New York, 1970. [all data]

Roth and Rist-Schumacher, 1944
Roth, W.A.; Rist-Schumacher, E., Beitrag zur thermochemie der sulfonsauren und saurechlorid, Z. Electrochem., 1944, 50, 7-9. [all data]

Entelis, Korovina, et al., 1960
Entelis, S.G.; Korovina, G.V.; Chirkov, N.M., The thermodynamics of propylene absorption by the H₂SO₄-H₂0 system, Dokl. Akad. Nauk SSSR, 1960, 134, 856-859. [all data]

Notes

Go To: Top, Reaction thermochemistry data, References

Symbols used in this document:

T Temperature

Δ_rG° Free energy of reaction at standard conditions

Δ_rH° Enthalpy of reaction at standard conditions

Δ_rS° Entropy of reaction at standard conditions
Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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T	Temperature
Δ_rG°	Free energy of reaction at standard conditions
Δ_rH°	Enthalpy of reaction at standard conditions
Δ_rS°	Entropy of reaction at standard conditions