Sodium polysulfide

Sodium polysulfide
Sodium pentasulfide Na2S5, a representative component of sodium polysulfide
Crystal structure of Na2S5. Purple: Na, yellow: S
Names
Other names
Sodium sulfane; Viradon
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.014.261
EC Number
  • 215-686-9
  • tetrasulfide: 234-805-5
UN number UN3266
  • tetrasulfide: InChI=1S/2Na.H2S4/c;;1-3-4-2/h;;1-2H/q2*+1;/p-2
    Key: ZLCCLBKPLLUIJC-UHFFFAOYSA-L
  • pentasulfide: InChI=1S/2Na.H2S5/c;;1-3-5-4-2/h;;1-2H/q2*+1;/p-2
    Key: WMEKSYHDIDMJMC-UHFFFAOYSA-L
  • tetrasulfide: [Na+].[Na+].[S-]SS[S-]
  • pentasulfide: [Na+].[Na+].[S-]SSS[S-]
Properties
Na2Sx, where x is 2 to 5
Appearance Dark red crystalline solids
Hazards
GHS labelling:
Danger
H228, H301, H311, H314, H400
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 Na2Sx, where x = 2 to 5. The species S2−
x
, called polysulfide anions, include disulfide (S2−2), trisulfide (S2−3), tetrasulfide (S2−4), and pentasulfide (S2−5). 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.