CAS Number: 10102-17-7
Molecular Formula: H10Na2O8S2
Molecular Weight: 248.19

Sodium thiosulfate pentahydrate is a hydrate consisting of sodium thiosulfate with 5 mol eq. of water.
Sodium thiosulfate pentahydrate has a role as an antidote to cyanide poisoning, a nephroprotective agent and an antifungal drug.
Sodium thiosulfate pentahydrate contains a sodium thiosulfate.

Sodium thiosulfate pentahydrate is an inorganic compound with the formula Na2S2O3.xH2O.
Typically Sodium thiosulfate pentahydrate is available as the colorless pentahydrate, Na2S2O3·5H2O.
The solid is an efflorescent (loses water readily) crystalline substance that dissolves well in water.

Sodium thiosulfate pentahydrate is used in gold mining, water treatment, analytical chemistry, the development of silver-based photographic film and prints, and medicine.
The medical uses of Sodium thiosulfate pentahydrate include treatment of cyanide poisoning and pityriasis.

Sodium thiosulfate pentahydrate is applied in a widely useful, thiosulfate-assisted, synthesis of a variety of diamine-CuCN complexes.
Sodium Thiosulfate is a white translucent crystals or powder that is common as the pentahydrate form; melting at 48 C; readily soluble in water and oil of turpentine; aqueous solution is slightly alkaline which decompose to sulfate and sulfide in the air.

Sodium thiosulfate pentahydrate is a moderate reducing agent.
Sodium thiosulfate pentahydrates major use is as a fixing agent in photography for developing film and the extracting silver from ore.
Sodium thiosulfate pentahydrate is used in chrome-tanning leather and in chemical manufacture as a source of sulfide ion.
Sodium thiosulfate pentahydrate is also used in paper, textile, and water treatment industry and gas purification.

Medical uses of Sodium thiosulfate pentahydrate:
Sodium thiosulfate pentahydrate is used in the treatment of cyanide poisoning.
Other uses of Sodium thiosulfate pentahydrate include topical treatment of ringworm and tinea versicolor, and treating some side effects of hemodialysis and chemotherapy.

In analytical chemistry, the most important use comes because the thiosulfate anion reacts stoichiometrically with iodine in aqueous solution, reducing it to iodide as the thiosulfate is oxidized to tetrathionate.
This particular use can be set up to measure the oxygen content of water through a long series of reactions in the Winkler test for dissolved oxygen.
Sodium thiosulfate pentahydrate is also used in estimating volumetrically the concentrations of certain compounds in solution (hydrogen peroxide, for instance) and in estimating the chlorine content in commercial bleaching powder and water.

Photographic processing:
Silver halides, e.g., AgBr, typical components of photographic emulsions, dissolve upon treatment with aqueous thiosulfate:
Sodium thiosulfate pentahydrate is used for both film and photographic paper processing; the sodium thiosulfate is known as a photographic fixer, and is often referred to as ‘hypo’, from the original chemical name, hyposulphite of soda.
Ammonium thiosulfate is typically preferred to sodium thiosulfate for this application.

Gold extraction:
Sodium thiosulfate and ammonium thiosulfate are a component of an alternative lixiviants to cyanide for extraction of gold.
Thiosulfate forms strong soluble complexes with gold(I) ions.
The advantages of this approach are that (i) thiosulfate is essentially nontoxic and (ii) that ore types that are refractory to gold cyanidation (e.g. carbonaceous or Carlin-type ores) can be leached by thiosulfate.
Some problems with this alternative process include the high consumption of thiosulfate, and the lack of a suitable recovery technique does not adsorb to activated carbon, which is the standard technique used in gold cyanidation to separate the gold complex from the ore slurry.

Neutralizing chlorinated water:
Sodium thiosulfate pentahydrate is used to dechlorinate tap water including lowering chlorine levels for use in aquariums, swimming pools, and spas (e.g., following superchlorination) and within water treatment plants to treat settled backwash water prior to release into rivers.
The reduction reaction is analogous to the iodine reduction reaction.

In pH testing of bleach substances, sodium thiosulfate neutralizes the color-removing effects of bleach and allows one to test the pH of bleach solutions with liquid indicators.
The relevant reaction is akin to the iodine reaction: thiosulfate reduces the hypochlorite (active ingredient in bleach) and in so doing becomes oxidized to sulfate.
Similarly, sodium thiosulfate reacts with bromine, removing the free bromine from solution.
Solutions of sodium thiosulfate are commonly used as a precaution in chemistry laboratories when working with bromine and for the safe disposal of bromine, iodine, or other strong oxidizers.

Two polymorphs are known of the pentahydrate.
The anhydrous salt exists in several polymorphs.
In the solid state, the thiosulfate anion is tetrahedral in shape and is notionally derived by replacing one of the oxygen atoms by a sulfur atom in a sulfate anion.
The S-S distance indicates a single bond, implying that the terminal sulfur holds a significant negative charge and the S-O interactions have more double-bond character.

On an industrial scale, sodium thiosulfate is produced chiefly from liquid waste products of sodium sulfide or sulfur dye manufacture.
When the protonation is conducted in diethyl ether at −78 °C, H2S2O3 (thiosulfuric acid) can be obtained.
Sodium thiosulfate pentahydrate is a somewhat strong acid with pKas of 0.6 and 1.7 for the first and second dissociations, respectively.

IUPAC Name: disodium;dioxido-oxo-sulfanylidene-sulfane;pentahydrate
Appearance: Colorless to white powder or chunks
Melting Point: 48 °C
Boiling Point: 100 °C
Density: 1.69 g/cm3
Hydrogen Bond Donor Count    : 5
Hydrogen Bond Acceptor Count: 9
Rotatable Bond Count: 0
Exact Mass: 247.96124818
Monoisotopic Mass: 247.96124818
Topological Polar Surface Area: 109 Ų

Heavy Atom Count: 12
Complexity: 82.5
Isotope Atom Count: 0
Defined Atom Stereocenter Count: 0
Undefined Atom Stereocenter Count: 0
Defined Bond Stereocenter Count: 0
Undefined Bond Stereocenter Count: 0
Covalently-Bonded Unit Count: 8
Compound Is Canonicalized    : Yes

Application(s) of Sodium thiosulfate pentahydrate:
-antidote to cyanide poisoning
-nephroprotective agent
-antifungal drug

Possible applications of Sodium thiosulfate pentahydrate:
Sodium thiosulfate pentahydrate offers a wide range of applications.
As a natural substance, for example, Sodium thiosulfate pentahydrate lends its healing power to sulfur-smelling hot water sources.
Sodium thiosulfate pentahydrate is usually administered intravenously, but also in the form of drinks and over the skin.

Sodium thiosulfate pentahydrate acts detoxifying and supports the mineral intake.
An advantage is that Sodium thiosulfate pentahydrate is very reasonable, easy to use and readily available.
In addition, Sodium thiosulfate pentahydrate acts as a reducing agent or antioxidant, which neutralizes free radicals.

Sodium thiosulfate pentahydrate also promotes the quality of drinking water by removing the chlorine or fluorine.
Sodium thiosulfate pentahydrate promotes the body’s detoxification.
To this end, Sodium thiosulfate pentahydrate provides sulfur to neutralize chlorine and fluorine in water or in the body.
Furthermore, Sodium thiosulfate pentahydrate supports the production of glutation in the body.
Sodium thiosulfate pentahydrate is used for the detoxification, removal and drainage of heavy metals such as mercury, uranium, thallium, barium, strontium and radioactive poisoning.
Crystalline serves as a fast acting antidote to gases such as carbonic acid, flue gas, exhaust gas, coking plant or blast furnace gas, in the case of toxic vapors such as chlorine, bromine, iodine, nitric oxide, aliphatic or aromatic nitro compounds and plastic fires, as well as in the case of chemical basic substances such as cyanides, nitriles, nitrites or aromatic compounds Amines such as aniline or toluidine.

Further applications of Sodium thiosulfate pentahydrate
Sodium thiosulfate pentahydrate makes an important contribution to health and can be dissolved in water or tea and used as a drink once a day.
The external application is also possible, for example as a foot bath together with baking powder or for massages.
Sodium thiosulfate pentahydrate is easily soluble in water and becomes yellowish-opaque by the precipitated sulfur.

Sodium thiosulfate pentahydrate is used as a fixing salt in photography.
Sodium thiosulfate pentahydrate removes chlorine from bleached tissue and paper.

Application in iodometry:
-Use in chrome leather fabrication
-Use to extract silver chloride from silver ore
-Use to produce galvanic gold and silver solutions
-Use as a bleaching agent for straw, bone, ivory
-As a reagent in analytical chemistry
-As an antidote to cyanide poisoning
-Use for drinking water treatment
-Use for fish aquariums for the dechlorination and neutralization of halogens
-As an additive in fats to protect against ripening in oils, soaps

Sodium thiosulfate pentahydrate offers many advantages, especially in the medical field, where it is used as an antidote to cyanide poisoning or to protect against calcification.
Sodium thiosulfate pentahydrate also dissolves calcified vessels.

Chemical Properties of Sodium thiosulfate pentahydrate:
Sodium thiosulfate pentahydrate occurs as odorless and colorless crystals, a crystalline powder or granules.
Sodium thiosulfate pentahydrate is efflorescent in dry air and deliquescent in moist air.

Uses of Sodium thiosulfate pentahydrate:

Production Methods of Sodium thiosulfate pentahydrate:
On an industrial scale, Sodium thiosulfate pentahydrate is produced chiefly from liquid waste products of sodium sulfide or sulfur dye manufacture.
Small-scale synthesis is done by boiling an aqueous solution of sodium sulfite with sulfur.

Pharmaceutical Applications of Sodium thiosulfate pentahydrate:
Sodium thiosulfate pentahydrate is used as an antioxidant in pharmaceuticals (ophthalmic, intravenous, and oral preparations).
Sodium thiosulfate pentahydrate has also been used for its antifungal properties and as a reagent in analytical chemistry.

Safety of Sodium thiosulfate pentahydrate:
Sodium thiosulfate pentahydrate is used in ophthalmic, intravenous, and oral pharmaceutical preparations.
Apart from osmotic disturbances, sodium thiosulfate is relatively nontoxic.
Sodium thiosulfate pentahydrate is moderately toxic by the subcutaneous route and mildly irritating to respiratory tract and skin.

Storage of Sodium thiosulfate pentahydrate:
Sodium thiosulfate pentahydrate decomposes on heating.
The bulk powder of Sodium thiosulfate pentahydrate should be stored in a cool place, and the container should be kept tightly closed in a dry and well-ventilated place.
Sodium thiosulfate pentahydrate should not be stored near acids.

Sodium thiosulfate pentahydrate is incompatible with iodine, with acids, and with lead, mercury, and silver salts.
Sodium thiosulfate pentahydrate may reduce the activity of some preservatives, including bronopol, phenylmercuric salts, and thimerosal.

Sodium thiosulfate pentahydrate, also known as sodium hydrosulfite, is used as an antidote to cyanide poisoning, but several studies have demonstrated that its efficacy in some pathological conditions is related to ectopic calcification.
The mechanisms of action, by which Sodium thiosulfate pentahydrate exerts its inhibitory effect on vascular mineralization, are not yet clear.
Sodium thiosulfate pentahydrate has been postulated that Sodium thiosulfate pentahydrate: (i) forms with calcium a more soluble complex than calcium phosphate and calcium oxalate, (ii) has antioxidant activity improving endothelial function, (iii) has acidosis properties.
However, O’Neil and Hardcastle demonstrated that the inhibitor effect of STS seems to be independent on calcium interactions or on pH, but could be due to a direct extracellular effect on calcification induced by cellular injury releasing cell debris and matrix vesicles.

Sodium thiosulfate pentahydrate is typically found in its pentahydrate form which is either white in colour, or colourless altogether.
This pentahydrate of sodium thiosulfate is described by the following chemical formula: Na2S2O3.5H2O.

In Sodium thiosulfate pentahydrates solid form, it is a crystalline solid which has a tendency to readily lose water.
Sodium thiosulfate pentahydrate is readily soluble in water and is also referred to as sodium hyposulfite.

Sodium thiosulfate pentahydrate can be noted that the shape of the thiosulfate ion is tetrahedral in the solid-state of sodium thiosulfate.
The distance between the two sulphur atoms in the thiosulfate ion is comparable to the distance between two sigma bonded sulphur atoms.
This implies that the sulphur which is not bonded to any oxygens holds a negative charge.

Properties of Sodium thiosulfate pentahydrate
Physical Properties
Sodium thiosulfate pentahydrate, Na2S2O3.5H2O , has a molar mass of 248.18 g/mol.
Sodium thiosulfate pentahydrate has a white, crystalline appearance as a solid and is odourless.
The pentahydrate of this salt has a melting point of 321.4 K and a boiling point of 373 K.
The solubility of Sodium thiosulfate pentahydrate in water is 70.1g/100 mL at 20oC and 231g/100mL at 100.

Chemical Properties
The sodium thiosulfate salt is neutral in charge.
However, it dissociates in water and some other polar solvents to yield Na+ and S2O32-
Despite being stable at standard conditions, the sodium thiosulfate salt decomposes at high temperatures to yield sodium sulfate along with sodium polysulfide.
The chemical equation for the reaction described above is given by
4Na2S2O3 ⟶ 3Na2SO4 + Na2S5

When exposed to dilute acids such as dilute hydrochloric acid, the sodium thiosulfate salt undergoes a decomposition reaction to yield sulphur along with sulphur dioxide.
Na2S2O3 + 2HCl ⟶ 2NaCl + SO2 + H2O + S

The alkylation of Na2S2O3 yields S-alkyl thiosulfates.
These compounds are commonly referred to as Bunte salts.

Uses of Sodium thiosulfate pentahydrate:
Na2S2O3 is a very important chemical compound in the medical treatment of cyanide poisoning cases.
Sodium thiosulfate pentahydrate is also used medically to treat dermatophytosis (ringworm) and tinea versicolor.
The side effects of chemotherapy and hemodialysis (purification of blood) are treated with Na2S2O3.
Sodium thiosulfate pentahydrate is a very important compound in analytical chemistry since it stoichiometrically reacts with iodine to reduce it to the iodide ion while it is oxidized to the S4O62- (tetrathionate) ion.
Sodium thiosulfate salts are used as photographic fixers due to the ability of the thiosulfate ions to react with silver halides, which make up photographic emulsions.
Ammonium thiosulfate and sodium thiosulfate make up lixiviants (liquid mediums used in hydrometallurgy) which are used in the extraction of gold from its ores.
In order to reduce the chlorine levels in water bodies, Na2S2O3 is used in the dechlorination process.

Medical uses of Sodium thiosulfate pentahydrate:
Sodium thiosulfate pentahydrate, is a medicine that is used to treat cyanide poisoning, pityriasis versicolor, and cisplatin side effects.
Sodium thiosulfate pentahydrate is frequently used after the drug sodium nitrite for cyanide poisoning and is usually only prescribed in severe situations.
Sodium thiosulfate pentahydrate is a toxin with a modest toxicity level.
Large dosages may produce nausea, vomiting, abdominal cramps, diarrhoea, metabolic acidosis, and hypernatremia, as well as gastrointestinal discomfort.

Sodium thiosulfate, pentahydrate
Disodium thiosulfate pentahydrate
sodium thiosulphate pentahydrate
Thiosulfuric acid (H2S2O3), disodium salt, pentahydrate
Thiosulfuric acid, disodium salt, pentahydrate
Sodium thiosulfate (pentahydrate)
Thiosulfuric acid (H2S2O3), sodium salt, hydrate (1:2:5)
Sodium Thiosulfate Pentahydrate Solution
CCRIS 3952
Sodium thiosulfate pentahydrate, 99+%, extra pure
Sodium thiosulfate pentahydrate, 99.5%, for analysis
Sodium thiosulfate pentahydrate, 99+%, for biochemistry
Sodium thiosulfate pentahydrate, 99.999%, (trace metal basis)
Sodium thiosulfate [USP:JAN]
Sulfactol (TN)
Detoxol (TN)
Sodium thiosulfate (USP)
Sodium thiosulphate hydrate
Sodium Thiosulfate, crystal
sodium thiosulfate-pentahydrate
sodium thio-sulfate pentahydrate
Sodium thiosulfate pentahydrate ACS
Sodium thiosulfate hydrate (JP17)
sodium sulfurothioate–water (1/5)
Sodium Thiosulfate (Industrial Grade)
Sodium thiosulfate pentahydrate Biochemical grade