Sodium thiosulfate pentahydrate (Na₂S₂O₃), also spelled Sodium Thiosulphate Pentahydrate, is a colorless crystalline compound that is more familiar as the pentahydrate, Na₂S₂O₃•5H₂O.  It is an efflorescent, monoclinic crystalline substance also called Sodium Hyposulphite or “Hypo.”
Sodium thiosulfate or Sodium Thiosulphate is generally used as pentahydrate, in certain applications like photography, pharmaceutical, table salt  and some other applications, it is used as anhydrous sodium thiosulfate or Sodium Thiosulphate Anhydrous.

Sodium Thiosulfate Pentahydrate

Typical Analysis	Crystal Photo
	(Pea Shape)
Assay, Na2S203 .5H20 min.	99.00%
PH of 10% solution	7.0-8.5
Sodium Sulfite (Na2S03) max.	10 ppm
Iron (Fe), Max % by wt. max.	20ppm
Heavy Metals (as Pb) max.	10 ppm

Uses:
Photographic industry- as solubilized undeveloped silver salts in fixing of films and print.
Paper industry and water treatment - as antichlor.
Textile industry -as mordant in dyeing and printing textiles.
Tanning industry - as reducer of hexavalent chromium.

Analytical chemistry - as reagent.

Other hot product: Sodium Metabisulphite |Sodium Bicarbonate