CAS 10117-38-1PubChem CID 24958
Potassium Sulfite
- IUPAC name
- dipotassium;sulfite
- Molecular formula
- K2O3S
- Molecular weight
- 158.26 g/mol
- Exact mass
- 157.88422800 Da
- Topological polar surface area
- 82.4 Ų
- Hydrogen-bond donors
- 0
- Hydrogen-bond acceptors
- 4
- Covalent units
- 3
- Defined stereocentres
- 0
Also known as
Dipotassium sulfitePotassium sulphiteSulfurous acid, dipotassium saltPotassium sulfite (K2SO3)UNII-015KZC652ESulfurous acid, potassium saltHSDB 5052015KZC652E
16 more reported names
EINECS 233-321-1DIPOTASSIUM SULPHITEPOTASSIUM SULFITE [MI]INS NO.225POTASSIUM SULFITE [FCC]POTASSIUM SULFITE [HSDB]INS-225EC 233-321-1E-225RefChem:175607POTASSIUM SULFITE [INCI]PotassiumsulfiteSulfurous acid, potassium salt (1:2)Potassium sulfite(IV)KaliumsulfitE225
External database identifiers
- EPA DTXSID:DTXSID80889532
Evidence from additional scientific databases
NIH PubChem PUG-View
Exact identifier match24958
Attributed physical-property, hazard, environmental and use annotations.
- Physical Description: Liquid Source: EPA Chemical Data Reporting (CDR)
- Physical Description: Dihydrate: White solid; Slowly oxidized by air to sulfate; [Merck Index] White powder; [MSDSonline] Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
- Solubility: White crystals or crystalline powder; sol in about 3.5 parts water; decomposed by diluted acids with evolution of sulfur dioxide; pH about 8 /dihydrate/ Source: Hazardous Substances Data Bank (HSDB)
- Solubility: White-yellowish, hexagonal form; insol in ammonia; slightly sol in alcohol /dihydrate/ Source: Hazardous Substances Data Bank (HSDB)
- Note: This chemical does not meet GHS hazard criteria for 81.5% (242 of 297) of all reports. Source: European Chemicals Agency (ECHA)
- Signal: Warning Source: European Chemicals Agency (ECHA)
- GHS Hazard Statements: H315 (16.5%): Causes skin irritation [Warning Skin corrosion/irritation]; H319 (18.2%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]; H335 (16.2%): May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation] Source: European Chemicals Agency (ECHA)
- Precautionary Statement Codes: P261, P264, P264+P265, P271, P280, P302+P352, P304+P340, P305+P351+P338, P319, P321, P332+P317, P337+P317, P362+P364, P403+P233, P405, and P501 (click each P-code to see the statement) Source: European Chemicals Agency (ECHA)
- ECHA C&L Notifications Summary: Aggregated GHS information provided per 297 reports by companies from 10 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.; Reported as not meeting GHS hazard criteria per 242 of 297 reports by companies.; There are 7 notifications provided by 55 of 297 reports by companies with hazard statement code(s).; Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website. Source: European Chemicals Agency (ECHA)
- Signal: Danger Source: Hazardous Chemical Information System (HCIS), Safe Work Australia
- GHS Hazard Statements: H302: Harmful if swallowed [Warning Acute toxicity, oral]; H318: Causes serious eye damage [Danger Serious eye damage/eye irritation] Source: Hazardous Chemical Information System (HCIS), Safe Work Australia
- Precautionary Statement Codes: P264, P264+P265, P270, P280, P301+P317, P305+P354+P338, P317, P330, and P501 (click each P-code to see the statement) Source: Hazardous Chemical Information System (HCIS), Safe Work Australia
- Cosmetic Ingredient Review Finding(s): Safe in the present practices of use and concentration. Ingredient, concentration, and use information are available in documents discoverable at https://cir-reports.cir-safety.org Source: Cosmetic Ingredient Review (CIR)
- Consumer Uses: Etching agent; Soil amendments (fertilizers) Source: EPA Chemical Data Reporting (CDR)
- Industry Uses: Reducing agent; Soil amendments (fertilizers) Source: EPA Chemical Data Reporting (CDR)
- Cosmetic Ingredient Review Link: CIR ingredient: Potassium Sulfite Source: Cosmetic Ingredient Review (CIR)
- Sources/Uses: Used in photography, food and cosmetics (preservative and antioxidant), and drugs (cathartic and diuretic); [HSDB] Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
- Industrial Processes with risk of exposure: Photographic Processing [Category: Other] Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
- Uses: Photography; preservative and antioxidant in foods Source: Hazardous Substances Data Bank (HSDB)
- Uses: Medication: cathartic, diuretic Source: Hazardous Substances Data Bank (HSDB)
- Uses: COMPONENT OF PHOTOGRAPHIC DEVELOPERS; FOOD ADDITIVE (EG, PRESERVATIVE & ANTIOXIDANT); INGREDIENT IN COSMETICS (EG, HAIR PREPARATIONS) Source: Hazardous Substances Data Bank (HSDB)
Mapped by: Existing checksum-valid CAS to unique PubChem CID match. Retrieved: 2026-08-31. Open source record
Scientific classifications and hazard annotations provide context and do not replace the market-specific regulatory decision shown above.
Additional source coverage and match status
| Source | Result | Checked |
|---|---|---|
| EMBL-EBI ChEBI | No exact record | 2026-08-31 |
| NIH PubChem PUG-View | Exact match | 2026-08-31 |
A recorded no-match is useful evidence that the source was checked; it is not a claim that the substance does not exist elsewhere.
Retrieved from NIH PubChem on 2026-08-31 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.