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

Ethylene

Ethylene is a colorless gas with a sweet odor.

CAS 74-85-1 C2H4 28.05 g/mol Danger

01 · Identification

What Ethylene is

Ethylene is a colorless gas with a sweet odor. Its molecular formula is C2H4 and its molecular weight is 28.05 g/mol. It boils at -104 °C, melts at -169 °C.

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

CAS number74-85-1
EC number200-815-3
Index number601-010-00-3
Molecular formulaC2H4
Molecular weight28.05 g/mol
Chemical class Flammable 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 Ethylene
CodeHazard statement
H220 Extremely flammable gas.
H336 May cause drowsiness or dizziness.

Precautionary statements: P210, P233, P403

03 · Physical and chemical properties

Ethylene 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 -103.8 °C (-154.8 °F) HSDB
-102.4 °C (-152.3 °F) at 700 mmHg HSDB
-103.72 °C (-154.7 °F) at 760 mmHg CAMEO
Melting point -169.18 °C (-272.5 °F) HSDB
-169.11 °C (-272.4 °F) CAMEO
-169.2 °C (-272.6 °F) ICSC
Density 0.569 g/cm³ at -103.8 °C CAMEO
0.568 g/cm³ at -104 °C DOE PAC
Solubility Slightly soluble in water HSDB
Very soluble in ethanol, ether; soluble in acetone acid, benzene HSDB
In water, 131 mg/L at 25 °C at 25 °C HSDB
Vapor pressure 52100 mmHg at 25 °C HSDB
51200 mmHg at 25 °C DOE PAC
60760 mmHg at 15 °C ICSC
Flash point -100 °C (-148 °F) HSDB
-136.11 °C (-213 °F) CAMEO
Autoignition temperature 450 °C (842 °F) HSDB
440 °C (824 °F) ICSC
Lower explosive limit (LEL) 2.7 % by volume HSDB
2.75 % by volume CAMEO
Upper explosive limit (UEL) 36 % by volume HSDB
28.6 % by volume CAMEO
Vapor density 0.98 (air = 1) HSDB
Odor threshold Detection in air by odor (purity not specified) 2.60x10+2 ppm. HSDB
Odor Index at 20 °C = 57,100 at 20 °C HSDB
Odor Threshold Low: 17.0 [ppm] Haz-Map
Critical temperature and pressure 9.2 °C (48.6 °F) HSDB
Corrosivity Ethylene is a noncorrosive gas. HSDB

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

04 · Handling and storage

Storing and handling Ethylene

Storage conditions

Store in cool dry, well-ventilated location. Protect against static electricity and lightning. Isolate from oxidizing materials, halogens, and other combustibles.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Incompatible materials: Strong oxidizing agents, carbon tetrachloride, chlorine, copper, vinyl compounds.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

Peroxidizable monomer may initiate exothermic polymerization of the bulk material [Bretherick 1979. p. 160]. Ethylene in the presence of aluminum chloride may undergo a violent reaction [J. Inst. Pet. 33:254. 1947]. Ozone and ethylene react explosively [Berichte 38:3837]. Ethylene can polymerize at low pressure if catalyzed by titanium halides. (Sundaram, K. M, M. M. Shreehan, E. F. Olszewski. "Ethylene." Kirk-Othmer Encyclopedia of Chemical Technology. John Wiley & Sons, Inc. 2001.)

Source: CAMEO Chemicals

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

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