Sodium polysulfide

Sodium polysulfide
	Sodium pentasulfide, a representative component of sodium polysulfide
Names
	Other names Sodium sulfane; Viradon
Identifiers
CAS Number	1344-08-7; tetrasulfide: 12034-39-8;
3D model (JSmol)	tetrasulfide: Interactive image; pentasulfide: Interactive image;
ChemSpider	tetrasulfide: 74748;
ECHA InfoCard	100.014.261
EC Number	215-686-9;
PubChem CID	tetrasulfide: 82835; pentasulfide: 129677176;
UN number	UN3266
CompTox Dashboard (EPA)	DTXSID9051296 ;
	SMILES tetrasulfide: [Na+].[Na+].[S-]SS[S-]; pentasulfide: [Na+].[Na+].[S-]SSS[S-];
Properties
Chemical formula	Na2Sx
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H228, H301, H311, H314, H400
Precautionary statements	P210, P240, P241, P260, P264, P270, P273, P280, P301+P310, P301+P330+P331, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P310, P312, P321, P322, P330, P361, P363, P370+P378, P391, P405, P501
NFPA 704 (fire diamond)	3 0 1
Flash point	Non-combustible
Safety data sheet (SDS)	AGFA
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Sodium polysulfide is a general term for salts with the formula Na₂S_x, where x = 2 to 5. The species S_x²⁻, called polysulfide anions, include disulfide (S₂²⁻), trisulfide (S₃²⁻), tetrasulfide (S₄²⁻), and pentasulfide (S₅²⁻). In principle, but not in practice, the chain lengths could be longer. The salts are dark red solids that dissolve in water to give highly alkaline and corrosive solutions. In air, these salts oxidize, and they evolve hydrogen sulfide by hydrolysis.