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

Fluorine

Fluorine is a pale yellow, diatomic gas or liquid with a sharp penetrating odor.

CAS 7782-41-4 F2 37.997 g/mol Danger

01 · Identification

What Fluorine is

Fluorine is a pale yellow, diatomic gas or liquid with a sharp penetrating odor. Its molecular formula is F2 and its molecular weight is 37.997 g/mol. It boils at -188 °C, melts at -220 °C.

Under the GHS it carries the signal word Danger. It is classed as reactive agents - 4th degree.

CAS number7782-41-4
EC number231-954-8
Index number009-001-00-0
Molecular formulaF2
Molecular weight37.997 g/mol
Chemical class Reactive agents - 4th degree

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 Fluorine
CodeHazard statement
H270 May cause or intensify fire; oxidiser.
H330 Fatal if inhaled.
H314 Causes severe skin burns and eye damage.

Precautionary statements: P260, P271, P280, P301, P304, P310, P331

03 · Physical and chemical properties

Fluorine 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 -188.13 °C (-306.6 °F) HSDB
-188.33 °C (-307 °F) NIOSH
-188.11 °C (-306.6 °F) at 760 mmHg CAMEO
Melting point -219.67 °C (-363.4 °F) triple point HSDB
-219.44 °C (-363 °F) NIOSH
-219.61 °C (-363.3 °F) CAMEO
Density 0.0017 g/cm³ at 25 °C HSDB
1.553 g/cm³ at 25 °C DOE PAC
1.5127 g/cm³ at -188.13 °C, liquid HSDB
Solubility Reacts NIOSH
Decomposes in water decomposes HSDB
Soluble in water with decomposition, forming hydrofluoric acid. decomposes HSDB
Vapor pressure 760 mmHg HSDB
5000000 mmHg at 25 °C HSDB
760 mmHg above this value NIOSH
Autoignition temperature Not flammable (USCG, 1999) CAMEO
Lower explosive limit (LEL) Nonflammable Gas, but an extremely strong oxidizer. NIOSH
Vapor density 1.695 (air = 1) Air = 1.29 HSDB
1.695 (air = 1) CAMEO
1.3 (air = 1) ICSC
Odor threshold 0.035 ppm HSDB
0.14 ppm HSDB
Low odor threshold= 6.0 mg/cu m, High odor threshold= 6.0 mg/cu m, Irritating concn= 50.0 mg/cu m HSDB
Critical temperature and pressure -129 °C (-200.2 °F) HSDB
Corrosivity Corrosive gas HSDB

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

04 · Fire and explosion

Fire and explosion behaviour of Fluorine

These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.

Fire and explosion

... It reacts violently with a wide range of both organic and inorganic compounds and thus is a dangerous fire and explosion risk in contact with such materials.

Source: HSDB

05 · Handling and storage

Storing and handling Fluorine

Storage conditions

Store in cool, dry, well-ventilated location. Outside or detached storage is preferred. Isolate from all other storage.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Strong oxidizer. Reacts with every known element except, helium, neon, argon. Reacts with all materials except for some Teflons and some metals at low temperatures. Water reactive. Reacts with water to form hydrogen fluoride and oxygen.

Source: Hazardous Substances Data Bank (HSDB)

Planning storage for a mix of chemicals? Check Fluorine in the storage compatibility matrix →

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