Nitrous acid
- Formula: HNO2
- Molecular weight: 47.0134
- IUPAC Standard InChI: InChI=1S/HNO2/c2-1-3/h(H,2,3)
- IUPAC Standard InChIKey: IOVCWXUNBOPUCH-UHFFFAOYSA-N
- CAS Registry Number: 7782-77-6
- 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: HNO2; Kyselina dusite; Nitrosyl hydroxide; Nitrous acid, trans; HONO
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Gas phase 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.
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°gas | -76.73 | kJ/mol | Review | Chase, 1998 | Data last reviewed in June, 1963 |
| Quantity | Value | Units | Method | Reference | Comment |
| S°gas,1 bar | 249.41 | J/mol*K | Review | Chase, 1998 | Data last reviewed in June, 1963 |
Gas Phase Heat Capacity (Shomate Equation)
Cp° = A + B*t + C*t2 + D*t3 +
E/t2
H° − H°298.15= A*t + B*t2/2 +
C*t3/3 + D*t4/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t2/2 + D*t3/3 −
E/(2*t2) + G
Cp = heat capacity (J/mol*K)
H° = standard enthalpy (kJ/mol)
S° = standard entropy (J/mol*K)
t = temperature (K) / 1000.
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| Temperature (K) | 298. - 1200. | 1200. - 6000. | 298. - 2000. | 2000. - 6000. |
|---|---|---|---|---|
| A | 24.89974 | 73.65137 | 37.79020 | 79.10390 |
| B | 91.37563 | 4.854988 | 54.22820 | 1.667420 |
| C | -64.84614 | -0.921409 | -27.25140 | -0.263444 |
| D | 17.92007 | 0.060837 | 5.100990 | 0.014898 |
| E | -0.134737 | -9.111790 | -0.510291 | -15.04800 |
| F | -88.13596 | -119.3896 | -93.99160 | -130.3780 |
| G | 254.2671 | 310.3440 | 277.0960 | 311.3580 |
| H | -76.73498 | -76.73498 | -78.82660 | -78.82660 |
| Reference | Chase, 1998 | Chase, 1998 | Chase, 1998 | Chase, 1998 |
| Comment | Data last reviewed in June, 1963 | Data last reviewed in June, 1963 | Data last reviewed in June, 1963 | Data last reviewed in June, 1963 |
References
Go To: Top, Gas phase thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Chase, 1998
Chase, M.W., Jr.,
NIST-JANAF Themochemical Tables, Fourth Edition,
J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, References
- Symbols used in this document:
S°gas,1 bar Entropy of gas at standard conditions (1 bar) ΔfH°gas Enthalpy of formation of gas at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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