Sodium persulfate
From Wikipedia, the free encyclopedia
| Sodium persulfate | |
|---|---|
| Other names | sodium peroxodisulfate sodium peroxodisulphate sodium peroxydisulfate sodium peroxydisulphate |
| Identifiers | |
| CAS number | [7775-27-1] |
| EINECS number | |
| 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 | |
| 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]:
The sulfate radical formed in situ has a standard electrode potential of 2.7V.
[edit] References
- ^ 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 2008 • Journal of Chemical Education 411

