Sodium Thiosulphate Pentahydrate 99%

Sodium Thiosulphate Pentahydrate 99% (CAS 10102-17-7, molecular formula Na2S2O3·5H2O) is a treatment chemical specified by municipal and industrial plant operators where dose consistency and impurity control directly affect finished water quality. China Chemicals supplies it at 99% min in pack sizes from 1 kg through to 1000 kg Bulk Bag, so laboratory trial quantities and full production volumes can be sourced from the same specification.

It is also traded as Hypo, Sodium Hyposulphite, Thiosulfate. Every consignment ships with a batch-specific Certificate of Analysis and the current Safety Data Sheet, and material is stored and picked under stock rotation so you receive product well inside its shelf life.

Typical applications

Dechlorination of treated water and effluent
Photographic fixing and film processing
Cyanide destruction in mining effluent
Textile bleach neutralisation
Analytical iodometric titration

Technical specification

Chemical name	Sodium Thiosulphate Pentahydrate 99%
Synonyms	Hypo, Sodium Hyposulphite, Thiosulfate
CAS number	10102-17-7
Molecular formula	Na2S2O3·5H2O
Appearance	Colourless transparent crystals
Assay	99.0% min
Sulphide	Pass test
Sulphite as Na2SO3	0.1% max
Water insolubles	0.01% max
pH (5% solution)	6.0 – 8.4
Iron (Fe)	10 ppm max

Values above are typical and are confirmed on the Certificate of Analysis issued against each batch. Tighter specifications can be quoted where a process requires them.

Packaging and supply

Available in 1 kg, 5 kg, 25 kg Bag, 1000 kg Bulk Bag. Bulk, road tanker and export drum quantities are quoted on request, including FOB and CIF terms for international shipment. Pricing shown is per pack in USD, exclusive of freight and any applicable duties.

Handling and safety

Transport classification: Not regulated · Not classified as hazardous. Store in the original closed container in a cool, well-ventilated area away from incompatible materials, and handle using appropriate personal protective equipment. Read the Safety Data Sheet in full before use — it is issued with every order and is available on request before purchase.

Supply to industry only. Products are sold for legitimate industrial, laboratory and manufacturing use. We may request end-use details and business registration before releasing an order.