Molekula
Sodium thiosulfate anhydrous (Technical Grade)
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 anhydrous (Technical Grade) is a chemical compound used in photographic fixing, water treatment, and analytical chemistry. It is a white, crystalline powder with no signal word required for safety. CAS: 7772-98-7, molecular formula: Na2O3S2, molecular weight: 158.11 g/mol. Stored at ambient temperature. Molekula supplies Sodium thiosulfate anhydrous (Technical Grade) 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.
Pricing & pack sizes
Pack sizes & pricing
Pricing on request — packs available from research to bulk quantities.
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Tell us how much you need and when — drums, IBCs, sacks or a one-off bulk lot. We'll manufacture or source it and come back with a price.
Prices exclude VAT/sales tax and shipping.
Specifications
| Property | Value |
|---|---|
| Appearance | White to off-white powder |
| pH | 6.5 - 9.5 (10% w/w, 25°C) |
| Purity | 98.0 - 102.0% |
| Heavy Metals (Pb) | ≤ 0.002% |
| Water insoluble matter | ≤ 0.1% |
| Iron (Fe) | ≤ 0.005% |
| Identification (IR) | Conforms to Reference |
| Sulfite | ≤ 0.5% |
| Alkaline Earth metals (Ca) | ≤ 0.2% |
| Sodium sulfide (Na2S) | ≤ 0.002% |
Storage & handling
| Property | Value |
|---|---|
| Storage Temperature | Ambient |
| Acidity | Neutral |
Literature values
Published physical properties of the substance, not batch specifications.
| Property | Value |
|---|---|
| Appearance | Powder |
| Melting Point | 48.5 °C |
| Refractive Index | 1.489 |
Source: PubChem CID 24477 (HSDB, ICSC)
Identification
| Property | Value |
|---|---|
| SKU | 90029226 |
| CAS Number | 7772-98-7 |
| IUPAC Name | disodium;dioxido-oxo-sulfanylidene-lambda6-sulfane |
| EC Number | 231-867-5 |
| Molecular Formula | Na2O3S2 |
| Molecular Weight | 158.11 |
| Exact Mass | 157.9084 |
| SMILES | [O-]S(=O)(=S)[O-].[Na+].[Na+] |
| InChIKey | AKHNMLFCWUSKQB-UHFFFAOYSA-L |
| InChI | InChI=1S/2Na.H2O3S2/c;;1-5(2,3)4/h;;(H2,1,2,3,4)/q2*+1;/p-2 |
| PubChem CID | 24477 |
| REACH Code | Y113 |
| TSCA Listed | Yes |
| HTS Code | 28323010 |
| Tariff Code | 2832100000 |
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, 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
- Chlorine Control
- Chlorine Cure
- Disodium thiosulfate
- Hypo
- SODIUM THIOSULFATE
- Sodium thiosulfate (Na2S2O3)
- Sodium thiosulfate, anhydrous
- Sodium thiosulphate
- Sodium thiosulphate (Na2S2O3)
- Thiosulfuric acid, disodium salt
Frequently asked questions
What is sodium thiosulfate anhydrous (technical grade) used for?
It is commonly used in photographic fixing, water treatment, and as a reagent in analytical chemistry.
What is the chemical formula and molecular weight?
The formula is Na2O3S2 and the molecular weight is 158.11 g/mol.
How should sodium thiosulfate anhydrous be stored?
It should be stored at ambient temperature, protected from moisture and contamination.
What grade is available?
We offer this product in Technical Grade.
Can Molekula supply it in bulk?
Yes, we can supply sodium thiosulfate anhydrous in bulk quantities—please contact us for pricing and availability.
What documentation comes with the order?
Each order includes a Certificate of Analysis and Safety Data Sheet (SDS) with the shipment.
Ready to order or need a custom pack?
Tell us the product, grade, and quantity — Molekula usually responds within one working day with pricing and lead time.