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

Pentane-2,4-dione

Pentane-2,4-dione is a colorless or slightly yellow liquid with a pleasant odor.

CAS 123-54-6 C5H8O2 100.12 g/mol Warning

01 · Identification

What Pentane-2,4-dione is

Pentane-2,4-dione is a colorless or slightly yellow liquid with a pleasant odor. Its molecular formula is C5H8O2 and its molecular weight is 100.12 g/mol. It boils at 138 °C, melts at -23 °C.

Under the GHS it carries the signal word Warning. It is classed as flammable agents - 3rd degree.

CAS number123-54-6
EC number204-634-0
Index number606-029-00-0
Molecular formulaC5H8O2
Molecular weight100.12 g/mol
Chemical class Flammable agents - 3rd degree

Other names for Pentane-2,4-dione

  • acetylacetone

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 wordWarning
Hazard statements assigned to Pentane-2,4-dione
CodeHazard statement
H226 Flammable liquid and vapour.
H302 Harmful if swallowed.

Precautionary statements: P210, P233, P241, P242, P270, P301, P312, P330, P403

03 · Physical and chemical properties

Pentane-2,4-dione 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
Boiling point 138 °C (280.4 °F) HSDB
140.39 °C (284.7 °F) at 760 mmHg CAMEO
140 °C (284 °F) ICSC
Melting point -23 °C (-9.4 °F) HSDB
-23.5 °C (-10.3 °F) CAMEO
Density 0.9706 g/cm³ HSDB
0.975 g/cm³ at 20 °C CAMEO
0.9721 g/cm³ at 25 °C HSDB
Solubility One part dissolves in about 8 parts water HSDB
Fairly soluble in neutral water HSDB
In water, 166,000 mg/L at 20 °C at 20 °C HSDB
Vapor pressure 6.9756 mmHg at 20 °C ICSC
2.96 mmHg Haz-Map
Flash point 38 °C (100.4 °F) HSDB
40.56 °C (105 °F) HSDB
33.89 °C (93 °F) HSDB
Autoignition temperature 340 °C (644 °F) HSDB
Lower explosive limit (LEL) 2.4 % by volume CAMEO
Upper explosive limit (UEL) 11.6 % by volume CAMEO
Vapor density 3.5 (air = 1) HSDB
3.45 (air = 1) ICSC
Odor threshold 0.010 ppm HSDB

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

04 · Handling and storage

Storing and handling Pentane-2,4-dione

Storage conditions

Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Storage class (TRGS 510): 3: Flammable liquids.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Incompatible materials: Strong oxidizing agents, reducing agents, strong bases, metals.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

Ketones, such as PENTANE-2,4-DIONE, are reactive with many acids and bases liberating heat and flammable gases (e.g., H2). The amount of heat may be sufficient to start a fire in the unreacted portion of the ketone. Ketones react with reducing agents such as hydrides, alkali metals, and nitrides to produce flammable gas (H2) and heat. Ketones are incompatible with isocyanates, aldehydes, cyanides, peroxides, and anhydrides. They react violently with aldehydes, HNO3, HNO3 + H2O2, and HClO4. May dissolve plastics (USCG, 1999).

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Pentane-2,4-dione in the storage compatibility matrix →

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