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

Hexan-2-one

Hexan-2-one is a colorless liquid with a characteristic acetone like odor, but more pungent.

CAS 591-78-6 C6H12O 100.16 g/mol Danger

01 · Identification

What Hexan-2-one is

Hexan-2-one is a colorless liquid with a characteristic acetone like odor, but more pungent. Its molecular formula is C6H12O and its molecular weight is 100.16 g/mol. It boils at 127 °C, melts at -55.5 °C.

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

CAS number591-78-6
EC number209-731-1
Index number606-030-00-6
Molecular formulaC6H12O
Molecular weight100.16 g/mol
Chemical class Flammable agents - 3rd degree

Other names for Hexan-2-one

  • methyl butyl ketone
  • butyl methyl ketone
  • methyl-n-butyl 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 wordDanger
Hazard statements assigned to Hexan-2-one
CodeHazard statement
H226 Flammable liquid and vapour.
H361f Suspected of damaging fertility.
H336 May cause drowsiness or dizziness.
H372 Causes damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.

Precautionary statements: P210, P233, P241, P242, P260, P270, P314, P403

03 · Physical and chemical properties

Hexan-2-one 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 127.2 °C (261 °F) HSDB
127.78 °C (262 °F) NIOSH
127.22 °C (261 °F) at 760 mmHg CAMEO
Melting point -55.5 °C (-67.9 °F) HSDB
-57.22 °C (-71 °F) NIOSH
Density 0.81 g/cm³ NIOSH
0.83 g/cm³ at 20 °C HSDB
0.812 g/cm³ at 20 °C CAMEO
Solubility Sol in acetone; miscible in ethanol and ether HSDB
1.4 wt% in water at 20 °C at 20 °C HSDB
In water, 1.72X10+4 mg/L at 20 °C at 20 °C HSDB
Vapor pressure 11 mmHg NIOSH
2 mmHg at 20 °C CAMEO
11.6 mmHg at 25 °C HSDB
Flash point 25 °C (77 °F) closed cup HSDB
35 °C (95 °F) HSDB
25 °C (77 °F) Closed cup HSDB
Autoignition temperature 423.89 °C (795 °F) HSDB
423 °C (793.4 °F) ICSC
Lower explosive limit (LEL) 1.2 % by volume HSDB
Upper explosive limit (UEL) 8 % by volume HSDB
Vapor density 3.5 (air = 1) HSDB
3.45 (air = 1) CAMEO
Odor threshold ODOR 3 PPM: 3= EASILY NOTICEABLE; IRRITATION 2 PPM: 2= FAINT. HSDB
0.28-0.35 mg/cu m HSDB
In air is 0.076 ppm and in water is 0.25 mg/L. HSDB

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

04 · Handling and storage

Storing and handling Hexan-2-one

Storage conditions

MATERIALS WHICH ARE TOXIC AS STORED OR WHICH CAN DECOMPOSE INTO TOXIC COMPONENTS ... SHOULD BE STORED IN A COOL WELL VENTILATED PLACE, OUT OF THE DIRECT RAYS OF THE SUN, AWAY FROM AREAS OF HIGH FIRE HAZARD, AND SHOULD BE PERIODICALLY INSPECTED. INCOMPATIBLE MATERIALS SHOULD BE ISOLATED ...

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Strong oxidizers.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

METHYL BUTYL KETONE is incompatible with oxidizing agents. It may also react with strong bases and reducing agents. (NTP, 1992)

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Hexan-2-one in the storage compatibility matrix →

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