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Sodium polysulfide is a general term for salts with the formula Na 2 S x, where x = 2 to 5. The species S x 2−, called polysulfide anions, include disulfide (S 2 2−), trisulfide (S 3 2−), tetrasulfide (S 4 2−), and pentasulfide (S 5 2−). In principle, but not in practice, the chain lengths could be longer.
Lenthionine is an organic polysulfide found in shiitake mushrooms. In commerce, the term "polysulfide" usually refers to a class of polymers with alternating chains of several sulfur atoms and hydrocarbons. They have the formula R 1 S n R 2. In this formula n indicates the number of sulfur atoms (or "rank").
Sodium sulfide is a chemical compound with the formula Na 2 S, or more commonly its hydrate Na 2 S·9H 2 O.Both the anhydrous and the hydrated salts in pure crystalline form are colorless solids, although technical grades of sodium sulfide are generally yellow to brick red owing to the presence of polysulfides and commonly supplied as a crystalline mass, in flake form, or as a fused solid.
Reduction of sulfur gives various polysulfides with the formula S x 2-, many of which have been obtained in crystalline form. Illustrative is the production of sodium tetrasulfide: 4 Na + S 8 → 2 Na 2 S 4. Some of these dianions dissociate to give radical anions, such as S 3 − gives the blue color of the rock lapis lazuli.
Potassium pentasulfide is the inorganic compound with the formula K 2 S 5. It is a red-orange solid that dissolves in water. It is a red-orange solid that dissolves in water. The salt decomposes rapidly in air.
Calcium sulfide is the chemical compound with the formula Ca S. This white material crystallizes in cubes like rock salt. This white material crystallizes in cubes like rock salt. CaS has been studied as a component in a process that would recycle gypsum , a product of flue-gas desulfurization .
In 1838, Swiss chemists reported the preparation of hydrophobic rubbery materials by the alkylation of sodium polysulfide with 1,2-dichloroethane. [2] In 1926 chemists Joseph C. Patrick and Nathan Mnookin further developed this class of materials, which first achieved commercial success as sealants for fuel lines, exploiting the solvent resistance of these materials.
Potassium sulfide is an inorganic compound with the formula K 2 S. The colourless solid is rarely encountered, because it reacts readily with water, a reaction that affords potassium hydrosulfide (KSH) and potassium hydroxide (KOH). Most commonly, the term potassium sulfide refers loosely to this mixture, not the anhydrous solid.