Molekula
Sodium thiosulfate pentahydrate
Supplying 4,500+ customers in over 80 countries
ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 2000 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need
Sodium thiosulfate pentahydrate is an inorganic compound widely used as a reducing agent, in photography for fixing developed film, and in water treatment to neutralize chlorine. It also serves in chemical synthesis, food processing, and as an antidote for cyanide poisoning. This white crystalline powder has a CAS number of 10102-17-7, a molecular formula of Na₂S₂O₃·5H₂O, and a molecular weight of 248.18. It is stable at ambient storage conditions and carries no signal word for hazard classification. Molekula supplies sodium thiosulfate pentahydrate from research to bulk quantities with full documentation and ISO 9001:2015 traceability.
Example image for illustration only. Other packaging and pack sizes are available.
Often bought together
Pricing & pack sizes
These pack sizes aren't a limit. Molekula manufactures, sources and repacks to order — if you need 500 kg and only see 1 kg listed, . We quote from grams to multi-tonne.
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1 kg — £46.40 per pack ex VAT · £55.68 inc. VAT
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Specifications
| Property | Value |
|---|---|
| Appearance | crystal or white solid |
| Heavy metals | ≤ 0.0005% |
| Chloride (Cl-) | ≤ 0.02% |
| Assay | ≥ 99.0% |
| Water insoluble matter | ≤ 0.005% |
| Iron (Fe) | ≤ 0.005% |
| Calcium (Ca) | ≤ 0.003% |
| Magnesium (Mg) | ≤ 0.001% |
| Sulphur Compounds | ≤ 0.00025% |
| Sulphates and sulphite | ≤ 0.05% |
| Total nitrogen (N) | ≤ 0.005% |
Storage & handling
| Property | Value |
|---|---|
| Storage Temperature | Ambient |
| Acidity | Neutral |
Literature values
Published physical properties of the substance, not batch specifications.
| Property | Value |
|---|---|
| Melting Point | 48 °C |
Source: PubChem CID 61475 (PAC Chemical Database)
Identification
| Property | Value |
|---|---|
| SKU | 59162714 |
| CAS Number | 10102-17-7 |
| IUPAC Name | disodium;dioxido-oxo-sulfanylidene-lambda6-sulfane;pentahydrate |
| Molecular Formula | Na2S2O3 · 5H2O |
| Molecular Weight | 248.18 |
| Exact Mass | 247.9612 |
| SMILES | O.O.O.O.O.[O-]S(=O)(=S)[O-].[Na+].[Na+] |
| InChIKey | PODWXQQNRWNDGD-UHFFFAOYSA-L |
| InChI | InChI=1S/2Na.H2O3S2.5H2O/c;;1-5(2,3)4;;;;;/h;;(H2,1,2,3,4);5*1H2/q2*+1;;;;;;/p-2 |
| PubChem CID | 61475 |
| REACH Code | Y113 |
| HTS Code | 28323010 |
| Tariff Code | 2832300000 |
Safety & GHS
Precautionary statements
- P280 Wear protective gloves/protective clothing/eye protection/face protection
Documents
Safety Data Sheets (SDS)
Available in English, French, German, Italian, Russian, Spanish.
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.
Synonyms
- Antichlor
- Disodium thiosulfate pentahydrate
- disodium;dioxido-oxo-sulfanylidene-lambda6-sulfane;pentahydrate
- Na2S2O3.5H2O
- pentahydrate of sodium thiosulfate
- Sodium Hyposulfite Pentahydrate
- sodium thiosulphate pentahydrate
- Thiosulfuric acid (H2S2O3), disodium salt, pentahydrate
- Thiosulfuric acid (H2S2O3), sodium salt, hydrate (1:2:5)
- Tinver
Frequently asked questions
What is sodium thiosulfate pentahydrate commonly used for?
It is primarily used in photography as a fixer to remove unexposed silver halide, in water treatment for chlorine and heavy metal detoxification, and in chemical synthesis as a reducing agent.
What is the chemical formula and molecular weight of sodium thiosulfate pentahydrate?
The formula is **Na₂S₂O₃·5H₂O**, and the molecular weight is **248.18 g/mol**.
What safety classification does sodium thiosulfate pentahydrate have?
It carries **no signal word** under GHS classification, indicating low acute toxicity.
How should sodium thiosulfate pentahydrate be stored?
Store it in a **cool, dry place at ambient temperature**, away from strong oxidizing agents.
Does Molekula offer sodium thiosulfate pentahydrate in bulk quantities?
Yes, we supply it in **bulk (drums, totes, or custom packaging)** for industrial and commercial applications.
What documentation is provided with an order of sodium thiosulfate pentahydrate?
Each order includes a **Certificate of Analysis (CoA)**, Material Safety Data Sheet (MSDS), and a packing slip with batch details.
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