Ammonium persulfate

Ammonium persulfate

Names
IUPAC names Ammonium peroxydisulfate Diazanium sulfonatooxy sulfate
Other names Diammonium peroxydisulfate Diammonium persulfate Diammonium peroxodisulphate
Identifiers
Jmol-3D images	Image
SMILES [NH4+].[NH4+].[O-]S(=O)(=O)OOS(=O)(=O)[O-]
Properties
Chemical formula	(NH4)2S2O8
Molar mass	228.18 g/mol
Appearance	White crystalline solid
Odor	Odorless
Density	1.98 g/cm3
Melting point	120 °C (248 °F; 393 K) (decomposes)
Boiling point	Decomposes
Solubility in water	80 g/100 mL (at 25 °C)
Solubility	Moderately soluble in methanol
Hazards
Safety data sheet	ScienceLab
Lethal dose or concentration (LD, LC):
LD50 (Median dose)	689 mg/kg, oral (rat)
Related compounds
Related compounds	Potassium persulfate Sodium persulfate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Ammonium persulfate (or APS) is a colorless inorganic compound with the formula (NH₄)₂S₂O₈, widely used as an etchant.

Properties

Chemical

Ammonium persulfate is used as radical initiator in polymerization, one example being the production of styrene-butadiene rubber.

When heated to 120°C, ammonium persulfate decomposes releasing sulfur oxides, nitrogen oxides, oxygen and ammonia.

Physical

Ammonium persulfate is a white solid, soluble in water.

Availability

Ammonium persulfate is sold by various electronics stores. It can also be purchased from eBay.

Preparation

Ammonium persulfate can be prepared by electrolysis of a cold concentrated solution of ammonium sulfate in concentrated sulfuric acid, at a high current density. Platinum electrodes are used.

Projects

• PCB etching
• Making the low explosive Tetraaminecopper(II) persulphate

Handling

Safety

Ammonium persulfate is a strong oxidizer and should be handled with proper protection. Inhalation is suspected to cause asthmatic effects, especially in women.

Ammonium peroxydisulfate is sensitive to moisture and will eventually decompose in a wet environment, releasing hydrogen peroxide.

Storage

Amonium peroxydisulfate should be stored in closed bottles or bags, away from moisture, acidic vapors or organic materials, preferably in a dark and dry environment. Ammonium persulfate does not store very well, and will become a wet mass, with little oxidizing potential after at least two years of storage.

Disposal

Heating the salt will cause it to decompose.

References

Relevant Sciencemadness threads

• Ammonium Persulphate production