Sodium thiosulfate pentahydrate CAS: 10102-17-7 is an inorganic substance with a chemical formula of Na2S2O3·5H2O. It is a colorless monoclinic crystal, odorless, and has a cool and bitter taste. The specific gravity is 1.729. When heated to 100 °C, it loses 5 crystal water. Easily soluble in water, insoluble in alcohol, with strong reducibility. It is easy to weather in dry air above 33℃, and it is deliquescent in moist air.
Sodium thiosulfate pentahydrate is a hydrate of sodium thiosulfate, and its aqueous solution is weakly alkaline. It is relatively stable in neutral and alkaline solutions, and decomposes rapidly in acidic solutions.
Physical properties:
Properties: Colorless monoclinic crystals, odorless, with a cool and bitter taste.
Melting point 40~45℃
Relative density 1.729 (17℃)
Solubility: Easily soluble in water, and the aqueous solution is nearly neutral. Soluble in turpentine and ammonia. Insoluble in ethanol. Decomposes in acidic solution.
When heated to 100 °C, 5 crystal waters are lost. It is easy to weather in dry air above 33℃, and it is deliquescent in moist air.
Sodium thiosulfate pentahydrate (Big Soda/Hybo) is a colorless and transparent crystal. It is a hydrate of sodium thiosulfate. It is easily soluble in water, and its aqueous solution is slightly alkaline. It weathers in dry air above 33℃ and loses crystal water. It is relatively stable in neutral and alkaline solutions, and decomposes rapidly in acidic solutions.
Chemical properties:
Reducibility: Soda soda also has strong reducibility and can reduce chlorine and other substances. Therefore, it can be used as a dechlorination agent for cotton fabrics after bleaching. In a similar way, iodine stains on the fabric can also be removed with it. In addition, large soda is also used for tanning leather, electroplating, and extracting silver from ore.
Complexing: Soda soda has a strong complexing ability and can form complexes with silver bromide. According to this nature, it can be used as a fixer. When washing the phase, the excessive amount of sodium bicarbonate reacts with the silver bromide on the non-sensitized part of the film to convert it into soluble, which is removed to fix the developing part.
Function and purpose:
Used in photography, film, textile, chemical fiber, paper, leather, pesticide industry,
1. The photosensitive industry is used as a photographic fixer. The paper industry is used as a dechlorinating agent after bleaching pulp. Used in printing and dyeing industry as a dechlorinating agent after bleaching cotton fabrics.
2. Analytical chemistry is used as a reagent for chromatography and volume analysis.
3. Used as detergent and disinfectant in medicine. Food industry is used as chelating agent, antioxidant, etc. Decyanide poisoning and mercury poisoning.
Used for skin pruritus, chronic urticaria, drug eruption.
Packaging, storage and transportation:
It can be packed in sack, glass fiber woven bag or wooden barrel, lined with plastic bag. Each bag (barrel) has a net weight of 25 kg or 50 kg.
Precautions for storage and transportation: It should be stored in a cool and dry warehouse. Avoid exposure to the sun and rain during transportation. Do not store or transport with acids and oxidants. The container must be sealed to prevent melting from moisture. If the package is damp, it means that the contents have been deliquescent and must be stacked separately from the dry package. Do not store in the open air, and handle damp packaging promptly. Water and sand can be used to fight the fire.
