Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Dipotassium peroxodisulphate

Dipotassium peroxodisulphate is colorless, triclinic crystals and is odorless.

CAS 7727-21-1 K2O8S2 270.33 g/mol Danger

01 · Identification

What Dipotassium peroxodisulphate is

Dipotassium peroxodisulphate is colorless, triclinic crystals and is odorless. Its molecular formula is K2O8S2 and its molecular weight is 270.33 g/mol.

Under the GHS it carries the signal word Danger. It is classed as reactive agents - 1st degree.

CAS number7727-21-1
EC number231-781-8
Index number016-061-00-1
Molecular formulaK2O8S2
Molecular weight270.33 g/mol
Chemical class Reactive agents - 1st degree

Other names for Dipotassium peroxodisulphate

  • potassium persulphate

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to Dipotassium peroxodisulphate
CodeHazard statement
H272 May intensify fire; oxidiser.
H302 Harmful if swallowed.
H335 May cause respiratory irritation.
H315 Causes skin irritation.
H319 Causes serious eye irritation.
H334 May cause allergy or asthma symptoms or breathing difficulties if inhaled.
H317 May cause an allergic skin reaction.

Precautionary statements: P261, P264, P270, P272, P280, P301, P302, P305, P312, P313, P330, P332, P333, P337, P338, P352

03 · Physical and chemical properties

Dipotassium peroxodisulphate properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Density 2.477 g/cm³ HSDB
2.5 g/cm³ ICSC
2.477 g/cm³ at 25 °C DOE PAC
Solubility INSOL IN ALCOHOL HSDB
5.2 G IN 100 CC OF HOT WATER @ 20 °C at 20 °C HSDB
Solubility in water, g/100ml at 20 °C: 5.2 at 20 °C ICSC
Vapor density 2.48 (air = 1) OSHA

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Handling and storage

Storing and handling Dipotassium peroxodisulphate

Storage conditions

Keep containers closed and store in cool dark places.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

POTASSIUM PERSULFATE PLUS A LITTLE POTASSIUM HYDROXIDE & WATER IGNITED POLYTHENE (POLYETHYLENE) LINER OF CONTAINER BY SIMULTANEOUS RELEASE OF HEAT & OXYGEN.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

POTASSIUM PERSULFATE is an oxidizing agent. Noncombustible but accelerates the burning of combustible material. Potassium persulfate plus a little potassium hydroxide and water released sufficient heat and oxygen to ignite a polythene (polyethylene) liner in a container. [MCA Case History 1155. 1955].

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Dipotassium peroxodisulph… in the storage compatibility matrix →

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