Potassium pyrosulfite - CP, ≥95% , CAS No.16731-55-8

CAS: 16731-55-8 Cat. No.: P110489 Formula: K2S2O5 Molecular Weight: 222.32 EC Number: 240-795-3
AVAILABLE TO ORDER
GRADE & PURITY CP ? Chemically Pure grade — moderate purity above technical grade but below analytical. Use for general lab reactions where ultra-low impurities aren't critical. ≥95%
Synonyms
POTASSIUM METABISULFITE|16731-55-8|Potassium disulfite|Potassium pyrosulfite|Dipotassium pyrosulfite|Sobisu|potassium metabisulphite|Potassium pentaoxodisulfate|Ins-224|Potassium metabisulfite [NF]|Potassium metabisulfite (e 224)|65OE787Q7W|Dipotassium di
Storage
Room temperature
Shipped In
Normal
★
Size
USA
Germany (EU)*
Price
Qty
25g
P110489-25g
3 In stock
—
$13.90
100g
P110489-100g
3 In stock
—

$14.90

$17.90
Save $3.00 (16.76%)
500g
P110489-500g
3 In stock
—

$20.90

$24.90
Save $4.00 (16.06%)
Enter a quantity for the sizes you want to add.
🧪
Why this grade

CP, ≥95% CP for sensitive chromatographic and analytical workflows requiring minimal baseline interference.

🌡

Storage & shipping

Room temperature Ships Normal Check lot-specific COA for exact specifications.

📋

Quality documents

SDS, COA, datasheet, and spec sheet available for download. Lot-specific COA accessible via lot number lookup.

📚

Literature proof

Cited in 13 peer-reviewed publications across chromatography, organic synthesis, and cross-coupling reactions.

Specifications

Synonyms
POTASSIUM METABISULFITE | 16731-55-8 | Potassium disulfite | Potassium pyrosulfite | Dipotassium pyrosulfite | Sobisu | potassium metabisulphite | Potassium pentaoxodisulfate | Ins-224 | Potassium metabisulfite [NF] | Potassium metabisulfite (e 224) | 65OE787Q7W | Dipotassium di
Specifications & Purity
CP, ≥95%
Storage
Room temperature
Shipped In
Normal
Grade
CP
Purity
≥95%
Names and Identifiers
Pubchem Sid508814654
Canonical Smiles[O-]S(=O)S(=O)(=O)[O-].[K+].[K+]
InChIKeyRWPGFSMJFRPDDP-UHFFFAOYSA-L
INCHI1S/2K.H2O5S2/c;;1-6(2)7(3,4)5/h;;(H,1,2)(H,3,4,5)/q2*+1;/p-2
Isomeric SMILES [O-]S(=O)S(=O)(=O)[O-].[K+].[K+]
UN Number 1759
Packing Group I
Molecular Weight 222.32
Reaxy-Rn 14412766
Reaxys-RN_link_address https://www.reaxys.com/reaxys/secured/hopinto.do?context=S&query=IDE.XRN=14412766&ln=

Documentation

📋 Safety Data Sheet (SDS)

Comprehensive hazard, handling, storage, and regulatory compliance document.

Download SDS →

✅ Certificate of Analysis (COA)

Lot-specific quality data. Enter your lot number to retrieve the exact COA.

Look up COA →

📊 Datasheet

Quick-reference summary of product specifications and applications.

View datasheet →

🔬 Specification Sheet

Full quality attributes and acceptance criteria for this grade.

View spec sheet →

Advanced Data

Taxonomic Classification

Taxonomy Tree

KingdomInorganic compounds
SuperclassMixed metal/non-metal compounds
ClassAlkali metal oxoanionic compounds
SubclassAlkali metal dithionites
Intermediate Tree Nodes Not available
Direct ParentAlkali metal dithionites
Alternative Parents Inorganic salts  Inorganic oxides  
Molecular FrameworkNot available
Substituents Alkali metal dithionite - Inorganic oxide - Inorganic salt
DescriptionThis compound belongs to the class of inorganic compounds known as alkali metal dithionites. These are inorganic compounds in which the largest oxoanion is dithionite, and in which the heaviest atom not in an oxoanion is an alkali metal.
External Descriptors Not available
3D Structure
Interactive Chemical Structure Model





Certificates(CoA,COO,BSE/TSE and Analysis Chart)
C of A & Other Certificates(BSE/TSE, COO):
Analytical Chart:

Find and download the COA for your product by matching the lot number on the packaging.

8 results found

Lot NumberCertificate TypeDateItem
A2220221Certificate of AnalysisOct 29, 2025 P110489
A2220225Certificate of AnalysisOct 29, 2025 P110489
A2220226Certificate of AnalysisOct 29, 2025 P110489
A1819047Certificate of AnalysisAug 18, 2025 P110489
I2504566Certificate of AnalysisJun 14, 2024 P110489
E1907173Certificate of AnalysisFeb 13, 2023 P110489
I2213082Certificate of AnalysisSep 19, 2022 P110489
I2213095Certificate of AnalysisSep 17, 2022 P110489
Chemical and Physical Properties
Melt Point(°C)190°C
Molecular Weight222.330 g/mol
XLogP3
Hydrogen Bond Donor Count0
Hydrogen Bond Acceptor Count6
Rotatable Bond Count0
Exact Mass221.846 Da
Monoisotopic Mass221.846 Da
Topological Polar Surface Area125.000 Ų
Heavy Atom Count9
Formal Charge0
Complexity136.000
Isotope Atom Count0
Defined Atom Stereocenter Count0
Undefined Atom Stereocenter Count0
Defined Bond Stereocenter Count0
Undefined Bond Stereocenter Count0
The total count of all stereochemical bonds0
Covalently-Bonded Unit Count3
Documents & Articles
Citations of This Product
Solution Calculators
Reviews

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