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Potassium metabisulfite

CAS 16731-55-8 K2S2O5 MW 222.32 In stock

Potassium metabisulfite is a white crystalline powder used as a preservative and antioxidant in food, wine, and pharmaceuticals. It is also employed in chemical synthesis and water treatment. Available in 1 kg, 5 kg, and 25 kg packaging, it has a CAS number of 16731-55-8, molecular formula K2S2O5, and molecular weight of 222.32 g/mol. Store at ambient temperatures. Signal word: Danger. Molekula supplies Potassium metabisulfite from research to bulk quantities with full documentation and ISO 9001:2015 traceability.

CoA by batch

Overview

Potassium metabisulfite is a white crystalline powder used as a preservative and antioxidant in food, wine, and pharmaceuticals. It is also employed in chemical synthesis and water treatment. Available in 1 kg, 5 kg, and 25 kg packaging, it has a CAS number of 16731-55-8, molecular formula K2S2O5, and molecular weight of 222.32 g/mol. Store at ambient temperatures. Signal word: Danger. Molekula supplies Potassium metabisulfite from research to bulk quantities with full documentation and ISO 9001:2015 traceability.

Specifications

Property Value
Appearance White powder
pH 3.8 - 4.8
Na ≤2%
Molecular Weight 222.32
Assay ≥97.2%
SO2 ≥56%
Cl ≤0.5%
Thiosulfate ≤0.1%

Storage & handling

Property Value
Storage Temperature Ambient
Shelf Life 24 months
Acidity Neutral

Identification

Property Value
CAS Number 16731-55-8
Molecular Formula K2S2O5
Molecular Weight 222.32
SMILES [O-]S(=O)S(=O)(=O)[O-].[K+].[K+]
REACH Code Y110
TSCA Listed Yes
HTS Code 28322000
Tariff Code 2832200000

Safety & GHS

Danger
  • GHS pictogram — Explosive Explosive GHS01
  • GHS pictogram — Compressed Gas Compressed Gas GHS04

Hazard statements

  • EUH031 Contact with acids liberates toxic gas
  • H315 Causes skin irritation
  • H318 Causes serious eye damage
  • H335 May cause respiratory irritation

Precautionary statements

  • P261 Avoid breathing dust/fume/gas/mist/vapours/spray
  • P280 Wear protective gloves/protective clothing/eye protection/face protection
  • P304+340 IF INHALED: Remove victim to fresh air and keep at rest in a position comfortable for breathing
  • P305+351+338 IF IN EYES: Rinse with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing
  • P332+313 IF skin irritation occurs: Get medical advice/attention
  • P337+313 If eye irritation persists get medical advice/attention

For research and industrial use only

Not for use in food, drugs, household, or in or on humans or animals. Consult the Safety Data Sheet before handling.

Documents

Certificate of Analysis (CoA) by batch

Enter a lot or batch number to retrieve the CoA for that specific batch. We can generate one from spec data if no PDF is on file.

Pricing & pack sizes

Pack sizes & pricing

  • 100 g

    £26.21 · per pack

  • 500 g

    £45.00 · per pack

Prices exclude VAT/sales tax and shipping. Bulk and custom pack sizes available on request.

Synonyms

No alternate names recorded for this product.

Frequently asked questions

What is potassium metabisulfite used for?

It is commonly used as a preservative in food and beverages, and as a reducing agent in chemical synthesis.

What is the chemical formula and molecular weight of potassium metabisulfite?

The formula is K2S2O5 and the molecular weight is 222.32 g/mol.

How should potassium metabisulfite be stored?

It should be stored at ambient temperature, in a dry and well-ventilated area.

What grade of potassium metabisulfite does Molekula supply?

Molekula supplies reagent grade potassium metabisulfite.

Can Molekula supply potassium metabisulfite in bulk?

Yes, Molekula can supply potassium metabisulfite in bulk quantities upon request.

What documentation comes with a purchase of potassium metabisulfite?

Each order includes a Certificate of Analysis and Safety Data Sheet (SDS).

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Tell us the product, grade, and quantity — Molekula usually responds within one working day with pricing and lead time.

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