Photographers' Formulary Sodium Thiosulfate (Hypo) Penta (Prismatic Rice) - 5 lbs

BH #PHSTP5LB • MFR #10-1361 5LB
Photographers' Formulary
Photographers' Formulary Sodium Thiosulfate (Hypo) Penta (Prismatic Rice) - 5 lbs
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Expected availability: 2-4 weeks

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Photographers' Formulary 10-1361 5LB Overview

Photographers' Formulary Sodium Thiosulfate is one of the few known substances that will dissolve silver bromide. As such it is universally used in modern photographic procedures.

In the process known as "fixation," the unexposed silver bromide is dissolved in the sodium thiosulfate by combining with it to form soluble complex thiosulfates of silver and sodium.

UPC: 675152136114

Photographers' Formulary 10-1361 5LB Specs

Hyposulfite of soda
Sodium hyposulfite
Sodium subsulfite
Sodium thiosulfate, pentahydrate
Thiosulfuric acid, disodium salt, pentahydrate
AppearanceLarge white monoclinic, colorless crystals and powder
UsesIn preparation of fixing baths
Ingredient in various reducers
Chemical FormulaNa2S2O3.5H2O
NotesHypo is available in two forms: anhydrous and, more commonly crystalline. Crystalline hypo, when dissolved, lowers the temperature of the water considerably, whereas anhydrous does not.

Always begin with water of at least 90°F/32°C when mixing the crystalline form. Use 64% of the anhydrous salt as a substitute for crystalline hypo.

Packaging Info
Package Weight5.28 lb
Box Dimensions (LxWxH)7 x 7 x 6.5"
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