Molekula
Potassium sodium tartrate tetrahydrate (Rochelle Salt)
Supplying 4,500+ customers in over 80 countries
ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 1999 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need
Potassium sodium tartrate tetrahydrate, also called Rochelle Salt, is a double salt of potassium and sodium tartrate widely used in chemical analysis, pharmaceuticals, and as a complexing agent in Fehling's solution and biuret reagent. This white crystalline powder has the chemical formula C4H4KNaO6, a molecular weight of 210.16 g/mol, and requires no special storage conditions under ambient temperatures. It carries no signal word for hazard classification, ensuring safe handling.
Molekula supplies Potassium sodium tartrate tetrahydrate (Rochelle Salt) at 99.0-102.0% purity in 1 kg packs, from £46.68 inc. VAT. It is in stock for same-day dispatch. Every batch ships with a certificate of analysis, and a safety data sheet is available. Larger quantities, up to multi-tonne, are quoted on request.
Example image for illustration only. Other packaging and pack sizes are available.
Often bought together
Pricing & pack sizes
In stock — same-day dispatch
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.
Need a different size? Add the nearest pack and change the size in your basket — we price it at the same rate per unit.
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1 kg — £38.90 per pack ex VAT · £46.68 inc. VAT
Need a different quantity or pack?
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 | Off-white to white crystals |
| Water | 24.0 - 26.0% |
| Heavy metals | ≤ 0.001% |
| pH | 6.5 - 8.5 (1% sol.) |
| Chloride (Cl-) | ≤ 100ppm |
| Assay | 99.0-102.0% |
| Iron (Fe) | ≤ 10ppm |
| Lead (Pb) | ≤ 2ppm |
| Mercury (Hg) | ≤ 1ppm |
| Arsenic (As) | ≤ 3ppm |
| Sulphates (SO4)(2-) | ≤ 0.05% |
| Identification (RAMAN) | Conforms to Reference |
Storage & handling
| Property | Value |
|---|---|
| Storage Temperature | Ambient |
| Acidity | Neutral |
Identification
| Property | Value |
|---|---|
| SKU | 11512541 |
| CAS Number | 6381-59-5 |
| Molecular Formula | C4H4KNaO6 |
| Molecular Weight | 210.16 |
| REACH Code | Y110 |
| TSCA Listed | Yes |
| HTS Code | 2918.13.3000 |
| Tariff Code | 29181300 |
Safety & GHS
Precautionary statements
- P280 Wear protective gloves/protective clothing/eye protection/face protection
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.
Quality certificates
Molekula Group is certified to ISO 9001:2015 (quality) and ISO 14001:2015 (environmental management), audited by a UKAS-accredited body. Both certificates are valid to 17 May 2028.
Synonyms
No alternate names recorded for this product.
Frequently asked questions
What is potassium sodium tartrate tetrahydrate (Rochelle Salt) commonly used for?
Rochelle Salt is used as a complexing agent in Fehling's solution and biuret reagent, and as a reagent in analytical chemistry for titrations and pH buffering.
What is the molecular formula and molecular weight of Rochelle Salt?
The molecular formula is C₄H₄KNaO₆, and the molecular weight is 210.16 g/mol.
How should Rochelle Salt be stored?
Store Rochelle Salt at ambient temperature in a cool, dry place, away from moisture and strong oxidizing agents.
What grade of Rochelle Salt does Molekula supply?
Molekula supplies Rochelle Salt to a specification with an assay of 99.0-102.0%, water content of 24.0-26.0%, and defined limits for impurities including heavy metals, chloride, sulphates, iron, lead, mercury and arsenic.
Can Molekula supply Rochelle Salt in bulk quantities?
Yes, Molekula can supply Rochelle Salt in bulk, with quantities tailored to meet your production or research needs.
What documentation comes with an order of Rochelle Salt?
Each order includes a Certificate of Analysis (CoA), Material Safety Data Sheet (MSDS), and a product specification sheet for reference.
Where can I buy Potassium sodium tartrate tetrahydrate (Rochelle Salt)?
Directly from Molekula, which lists Potassium sodium tartrate tetrahydrate (Rochelle Salt) in 1 kg packs from £46.68 inc. VAT, with a certificate of analysis for every batch. Larger quantities are quoted on request. Molekula's offices: United Kingdom, France, Spain, Germany, Italy, United States and China.
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.