Sodium persulfate

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Sodium persulfate
Other names sodium peroxodisulfate
sodium peroxodisulphate
sodium peroxydisulfate
sodium peroxydisulphate
Identifiers
CAS number [7775-27-1]
EINECS number [231-892-1 [231-892-1]]
Properties
Molecular formula Na2S2O8
Molar mass 238.03 g/mol
Appearance white powder
Density 2.40 g/cm³, solid
Melting point

180°C (decomposes)

Solubility in water 700 g/L (20°C)
Acidity (pKa) 6.0 (1% solution)
Hazards
EU classification not listed
NFPA 704
0
3
1
OX
R-phrases R8 R20 R22 R36 R37 R38 R42 R43
S-phrases S8 S17 S26 S36
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Sodium persulfate (Na2S2O8) is a chemical compound. It is a strong oxidizer. It is a severe irritant of skin, eyes, and respiratory system. It is almost non-hygroscopic and has particularly good ability to be stored for long time. It is easy and safe to handle. It is not combustible, but releases oxygen easily and assists combustion of other materials.

It is used as a bleach, both standalone (particularly in hair cosmetics) and as a detergent component. It is a replacement for ammonium persulfate in etching mixtures for zinc and printed circuit boards, and is used for pickling of copper and some other metals. It is a source of free radicals, making it useful as a radical initiator for emulsion polymerization reactions and for accelerated curing of low formaldehyde adhesives. It is also used as a soil conditioner and in manufacture of dyestuffs, modification of starch, bleach activator, desizing agent for oxidative desizing, etc.

Conditions/substances to avoid mixing persulfates with are: moisture, heat, flame, ignition sources, shock, friction, reducing agents, organic material, sodium peroxide, water, aluminium and powdered metals.

Sodium persulfate is a oxidizing agent in chemistry, for example in a synthesis of diapocynin from apocynin where sodium sulfate is the radical initiator [1]:

Diapocynin Synthesis

The sulfate radical formed in situ has a standard electrode potential of 2.7V.

[edit] References

  1. ^ Synthesis of Diapocynin Mina S. Dasari, Kristy M. Richards, Mikaela L. Alt, Clark F. P. Crawford, Amanda Schleiden, Jai Ingram, Abdel Aziz Amadou Hamidou, Angela Williams, and Patricia A. Chernovitz Vol. 85 No. 3 March 2008Journal of Chemical Education 411