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 Anhydrous

Formula	(Na2) S2O3
Molecular Weight	158
Assay as (Na2) S2O3	98 % Min.
20 % Solubility	Clear
PH of 10 % Solution	6.5 To 8.5
Description	White powder free from foreign particles.

Uses: Photographic industry - as solubilized undeveloped silver salts in fixing of films and print.

Other hot product: Sodium Metabisulphite |Sodium Bicarbonate