Sodium bisulfite
Names | |
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IUPAC name
Sodium hydrogen sulfite
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Other names
E222, sodium bisulphite
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Identifiers | |
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3D model (JSmol)
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ChEBI | |
ChEMBL | |
ChemSpider | |
ECHA InfoCard | 100.028.680 |
E number | E222 (preservatives) |
PubChem CID
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RTECS number |
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UNII | |
CompTox Dashboard (EPA)
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Properties | |
NaHSO3 | |
Molar mass | 104.061 g/mol |
Appearance | White solid |
Odor | Slight sulfurous odor |
Density | 1.48 g/cm3 |
Melting point | 150 °C (302 °F; 423 K) |
Boiling point | 315 °C (599 °F; 588 K) |
42 g/100 mL | |
Refractive index (nD)
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1.526 |
Hazards | |
GHS labelling: | |
H302 | |
P301+P312+P330 | |
NFPA 704 (fire diamond) |
2
0
1 |
Flash point | Non-flammable |
NIOSH (US health exposure limits): | |
PEL (Permissible)
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none[1] |
REL (Recommended)
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TWA 5 mg/m3[1] |
IDLH (Immediate danger)
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N.D.[1] |
Related compounds | |
Other anions
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Sodium sulfite Sodium metabisulfite |
Other cations
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Potassium bisulfite |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
what is ?) | (|
Infobox references | |
Sodium bisulfite (or sodium bisulphite, sodium hydrogen sulfite) is a chemical mixture with the approximate chemical formula NaHSO3. Sodium bisulfite in fact is not a real compound,[2] but a mixture of salts that dissolve in water to give solutions composed of sodium and bisulfite ions. It is a white solid with an odour of sulfur dioxide. Regardless of its ill-defined nature, "sodium bisulfite" is a food additive with E number E222.
Synthesis[]
Sodium bisulfite solutions can be prepared by treating a solution of suitable base, such as sodium hydroxide or sodium bicarbonate with sulfur dioxide.
- SO2 + NaOH → NaHSO3
- SO2 + NaHCO3 → NaHSO3 + CO2
Attempts to crystallise the product yield sodium disulfite, Na2S2O5.[3]
Sodium bisulfite is formed during the Wellman-Lord process.[4]
Reactivity and uses[]
Sodium bisulfite is a common industrial reducing agent, as it readily reacts with dissolved oxygen:
- 2 NaHSO3 + O2 → 2 NaHSO4
It is usually added to large piping systems to prevent oxidative corrosion. In biochemical engineering applications, it is helpful to maintain anaerobic conditions within a reactor.
It is used for preserving food and beverages.
See also[]
- Sodium metabisulfite
- Calcium bisulfite
- Potassium bisulfite
- Croscarmellose sodium
- Sulfurous acid
References[]
- ^ a b c NIOSH Pocket Guide to Chemical Hazards. "#0561". National Institute for Occupational Safety and Health (NIOSH).
- ^ Tudela, David; Jenkins, H. Donald B. (2003). "New Methods to Estimate Lattice Energies: Application to the Relative Stabilities of Bisulfite (HSO3−) and Metabisulfite (S2O52-) Salts". Journal of Chemical Education. 80 (12): 1482. Bibcode:2003JChEd..80.1482T. doi:10.1021/ed080p1482.
- ^ Johnstone, H. F. (1946). "Sulfites and Pyrosulfites of the Alkali Metals". Inorganic Syntheses. Inorganic Syntheses. 2. pp. 162–167. doi:10.1002/9780470132333.ch49. ISBN 9780470132333.
- ^ Kohl, Arthur L.; Nielsen, Richard B. (1997). "Sulfur Dioxide Removal". Gas Purification. Gulf Professional Publishing. pp. 554–555. ISBN 978-0-88415-220-0.
- Sodium compounds
- Bisulfites
- Reagents for organic chemistry
- Food additives
- Reducing agents
- E-number additives