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

5-Methyl-2-hexanone

5-Methyl-2-hexanone is colorless, clear liquid with a pleasant, fruity odor.

CAS 110-12-3 Warning

01 · Identification

What 5-Methyl-2-hexanone is

5-Methyl-2-hexanone is colorless, clear liquid with a pleasant, fruity odor. It boils at 144 °C, melts at -73.9 °C.

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

CAS number110-12-3
EC number203-737-8
Index number606-026-00-4
Chemical class Flammable agents - 3rd degree

Other names for 5-Methyl-2-hexanone

  • 5-methylhexan-2-one
  • isoamyl methyl ketone

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 5-Methyl-2-hexanone
CodeHazard statement
H226 Flammable liquid and vapour.
H332 Harmful if inhaled.

Precautionary statements: P210, P233, P241, P242, P260, P271, P304, P312, P403

03 · Physical and chemical properties

5-Methyl-2-hexanone 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 144 °C (291.2 °F) HSDB
143.89 °C (291 °F) NIOSH
143.89 °C (291 °F) at 760 mmHg CAMEO
Melting point -73.9 °C (-101 °F) HSDB
-73.89 °C (-101 °F) NIOSH
Density 0.81 g/cm³ NIOSH
0.888 g/cm³ at 20 °C HSDB
Solubility Miscible with ethanol and ether; very soluble in acetone, benzene; soluble in carbon tetrachloride HSDB
Miscible with most org solvents HSDB
In water, 5400 mg/L at 25 °C at 25 °C HSDB
Vapor pressure 5 mmHg NIOSH
5.77 mmHg at 25 °C HSDB
Flash point 35.56 °C (96 °F) HSDB
43.33 °C (110 °F) HSDB
36.11 °C (97 °F) NIOSH
Autoignition temperature 190.56 °C (375 °F) HSDB
191 °C (375.8 °F) ICSC
Lower explosive limit (LEL) 1 % by volume DOE PAC
1 % by volume at 93.33 °C HSDB
Upper explosive limit (UEL) 8.2 % by volume at 93.33 °C HSDB
Vapor density 3.9 (air = 1) HSDB
Odor threshold 0.012 ppm= detection in air, 0.049 ppm= recognition in air; (purity not specified) HSDB
Odor Threshold Low: 0.01 [ppm] Haz-Map
Odor Threshold High: 0.04 [ppm] Haz-Map

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

04 · Handling and storage

Storing and handling 5-Methyl-2-hexanone

Storage conditions

... Store in tightly closed containers in a cool, well ventilated area away from sources of oxidizers (such as perchlorates, peroxides, permanganates, chlorates, and nitrates), strong oxidizers (such as chlorine, bromine, and fluorine), reducing agents, and aldehydes. Sources of ignition such as smoking and open flames are prohibited where methyl isoamyl ketone is handled, used or stored. Metal containers involving the transfer of 5 gallons or more of methyl isoamyl ketone should be grounded and bonded. Drums must be equipped with self-closing valves, pressure vacuum bungs, and flame arresters.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

The vapor mixes well with air, explosive mixtures are easily formed.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

Ketones, such as 5-METHYLHEXAN-2-ONE, 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.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 5-Methyl-2-hexanone in the storage compatibility matrix →

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