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

Cyclopropane

Cyclopropane is a colorless gas with resembles that of petroleum ether odor.

CAS 75-19-4 C3H6 42.08 g/mol Danger

01 · Identification

What Cyclopropane is

Cyclopropane is a colorless gas with resembles that of petroleum ether odor. Its molecular formula is C3H6 and its molecular weight is 42.08 g/mol. It boils at -32.8 °C, melts at -127 °C, is soluble in water.

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

CAS number75-19-4
EC number200-847-8
Index number601-016-00-6
Molecular formulaC3H6
Molecular weight42.08 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 Cyclopropane
CodeHazard statement
H220 Extremely flammable gas.

Precautionary statements: P210, P233, P403

03 · Physical and chemical properties

Cyclopropane 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 -32.8 °C (-27 °F) at 760 mmHg HSDB
-32.89 °C (-27.2 °F) at 760 mmHg CAMEO
-33.5 °C (-28.3 °F) at 760 mmHg DOE PAC
Melting point -127.4 °C (-197.3 °F) HSDB
-127.39 °C (-197.3 °F) CAMEO
-126.6 °C (-195.9 °F) DOE PAC
Density 0.0019 g/cm³ at 0 °C, at 760 mmHg HSDB
1.879 g/cm³ at 0 °C DOE PAC
0.676 g/cm³ at -33 °C CAMEO
Solubility Soluble in benzene; very soluble in ethanol, ether. HSDB
FREELY SOL IN ALCOHOL, ETHER; SOL IN FIXED OILS, CONCN SULFURIC ACID; 1 VOL DISSOLVES IN ABOUT 2.7 VOL OF WATER AT 15 °C at 15 °C HSDB
3.81X10+2 mg/l water at 35 °C at 35 °C HSDB
Vapor pressure 5410 mmHg at 25 °C HSDB
Autoignition temperature 497.78 °C (928 °F) HSDB
500 °C (932 °F) CAMEO
Lower explosive limit (LEL) 2.41 % by volume HSDB
2.4 % by volume CAMEO
Upper explosive limit (UEL) 10.3 % by volume HSDB
Vapor density 1.88 (air = 1) HSDB
Critical temperature and pressure 124.72 °C (256.5 °F) HSDB
125.1 °C (257.2 °F) HSDB

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

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