Sodium persulfate

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Sodium persulfate
Sodium peroxydisulfate sample in watchglass.jpg
Sodium persulfate sample
IUPAC name
Sodium peroxydisulfate
Other names
Sodium peroxodisulfate
Sodium peroxodisulphate
Sodium peroxydisulphate
Molar mass 238.10 g/mol
Appearance White solid
Odor Odorless
Density 2.59 g/cm3
(Loose bulk density: 1.12 g/cm3)
Melting point 180 °C (356 °F; 453 K) (decomposes)
Boiling point Decomposes
55.6 g/100 ml (20 °C)
Vapor pressure ~0 mmHg
Safety data sheet Sigma-Aldrich
Flash point Non-flammable
Lethal dose or concentration (LD, LC):
920 mg/kg (rat, female, oral)
930 mg/kg (rat, male, oral)
Related compounds
Related compounds
Ammonium persulfate
Potassium persulfate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Sodium persulfate is the chemical compound with the formula Na2S2O8, the sodium salt of peroxydisulfuric acid. It is almost non-hygroscopic and has good shelf-life.

Sodium persulfate is preferred by many chemists over other persulfate salts, as it has good solubility in water and long shelf-life, while also having better performance than other persulfate salts.



Sodium persulfate is an oxidizer. It is a common oxidizing agent in Elbs persulfate oxidation or Boyland–Sims oxidation.

Heating it in solution to 80-90 Celsius for 2-3 minutes in presence of MnO2 leads to a decomposition reaction catalyzed by manganese dioxide:

2 Na2S2O8 + 2H2O → 4 NaHSO4 + O2

This reaction can be used as a qualitative test for the peroxodisulfate anion: just heat it with MnO2 and check the pH with a test strip. Low pH means positive test.


Sodium persulfate is a white solid, soluble in water.


Sodium persulfate can be bought from various electronic shops, as etching powder for zinc and printed circuit boards, as well as for pickling of copper and some other metals.


The salt is prepared by the electrolytic oxidation of sodium bisulfate:

2 NaHSO4 → Na2S2O8 + H2

Oxidation is conducted at a platinum anode.




Sodium persulfate is an oxidizer and forms combustible mixtures with organic materials such as paper.


In closed plastic or glass bottles.


Can be neutralized by heating it, which causes it to decompose.


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