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

Sulfur

Sulfur is yellow orthorhombic crystals and is odorless.

CAS 7704-34-9 S 32.07 g/mol Warning

Sulfur Safety Data Sheet →

01 · Identification

What Sulfur is

Sulfur is yellow orthorhombic crystals and is odorless. Its molecular formula is S and its molecular weight is 32.07 g/mol. It boils at 445 °C, melts at 95.3 °C.

Under the GHS it carries the signal word Warning.

CAS number7704-34-9
EC number231-722-6
Index number016-094-00-1
Molecular formulaS
Molecular weight32.07 g/mol

Other names for Sulfur

  • sulphur
  • brimstone
  • Sulfur, Dry
  • Sulfur, Molten
  • Sulphur, Molten

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 Sulfur
CodeHazard statement
H315 Causes skin irritation.

Precautionary statements: P264, P280, P302, P313, P332, P352

03 · Physical and chemical properties

Sulfur 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 444.61 °C (832.3 °F) HSDB
445 °C (833 °F) ICSC
Melting point 95.3 °C (203.5 °F) Sulfur rhombic transforms to monoclinic HSDB
106.8 °C (224.2 °F) gamma-Sulfur HSDB
120 °C (248 °F) amorphous ICSC
Density 2.07 g/cm³ rhombic HSDB
2.06 g/cm³ HSDB
1.96 g/cm³ HSDB
Solubility Insoluble in water; slightly soluble in ethanol, benzene, ethyl ether; soluble in carbon disulfide HSDB
Vapor pressure 0.00000395 mmHg at 30.4 °C HSDB
Flash point 207.22 °C (405 °F) HSDB
160 °C (320 °F) ICSC
Autoignition temperature 232.22 °C (450 °F) HSDB
232 °C (449.6 °F) ICSC
Lower explosive limit (LEL) 35 % by volume HSDB
Lower flammable limit for sulfur dust in air is 35 mg/L ... . HSDB
Vapor density Density of vapor/density of air, 470 °C: 7.837 at 470 °C HSDB
Critical temperature and pressure 1040 °C (1904 °F) HSDB

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

04 · Source notes

Further notes on Sulfur

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.

Corrosivity

Sulfur is not considered corrosive to the usual construction materials. However, acid-generating impurities, which may be introduced in handling and storage, create corrosive conditions.

Source: HSDB

05 · Handling and storage

Storing and handling Sulfur

Storage conditions

Store in cool, dry, well-ventilated location. Separate from chlorates, nitrates, other oxidizing materials, and hydrocarbons.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Reacts with oxidizing materials.

Source: Hazardous Substances Data Bank (HSDB)

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

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