What is Sodium thiosulfate Na2S2O3 CAS 7772-98-7?
Sodium thiosulfate pentahydrate is an inorganic substance with the chemical formula of Na2S2O3·5H2O.
Sodium thiosulfate Na2S2O3 is a colorless monoclinic crystal, odorless, and has a cool and bitter taste. The specific gravity is 1.729, heated to 100 ℃, and five crystals of water are lost.
Soluble in water, insoluble in alcohol, with strong reducibility.
Sodium thiosulfate Na2S2O3 is easily weathered in dry air above 33 ℃ and deliquescent in humid air.
| Items | Appearance | Na2S2O3•5H2O | Insolubles in water | Na2S | FeHeavy Metals (as Pb) | pH value (200g/L solution) | ||
| Standard | White crystallin | ≥99.0 |
|
≤0.001% | ≤0.001% | 6.5-9.5 | ||
Product characteristics of Sodium thiosulfate CAS 7772-98-7
1. Sodium thiosulfate pentahydrate has strong reducibility and can reduce chlorine and other substances.
2. Sodium thiosulfate has a strong complexation ability and can form a complex with silver bromide.
3. Sodium thiosulfate can be used as a sulfur supplement.
Sodium thiosulfate mainly has the following functions in concrete:
Water reducer: sodium thiosulfate can be used as a water reducer, which can reduce the water-cement ratio of concrete, reduce the evaporation rate of water, and thus reduce the shrinkage and cracking of concrete.
Early strength agent: sodium thiosulfate can promote the hydration reaction in concrete, and the hydration products can fill the pores in concrete and improve the density and strength of concrete.
At the same time, it can make mortar and concrete early strength, has a certain plasticizing effect on cement, and does not corrode steel bars.
According to the amount of concrete cementitious material, the amount of baking soda that needs to be added to one cubic meter of concrete is about 3% and 6%.
Inhibition of expansion: sodium thiosulfate reacts with hydrogen to form harmless sulfides, inhibiting concrete expansion.
Precautions of Sodium thiosulfate CAS 7772-98-7
1. This product is non-toxic and harmless, biodegradable, but not edible.
2. If it gets into the eyes, it should be rinsed with plenty of water in time.
3. If you cause allergies to part of the human body, you should consult a doctor in time.
