Ethene

Athanor · official

C₂H₄ · 28.05 g/mol

Also called ethylene, plant hormone

Reagents Functional groups

Open in Athanor

Drawn from its SMILES with RDKit

DangerExtremely flammable gas · May cause drowsiness or dizziness

Names and identifiers

IUPAC name: ethene
Synonyms: ethylene, plant hormone, ETHYLENE
+ 37 more
Acetene, Elayl, Olefiant gas, Athylen, Etileno, Liquid ethylene, Bicarburretted hydrogen, DTXSID1026378, 91GW059KN7, CHEBI:18153, RefChem:6430, DTXCID605931, 200-815-3, 682-561-7, Ethylene, pure, Caswell No. 436, Athylen [German], C2H4, HSDB 168, Ethylene [NF], Aethylen, Aethen, EPA Pesticide Chemical Code 041901, Liquid ethyene, EINECS 200-815-3, UN1038, UN1962, Ethylene (8CI), Ethylene, compressed, UNII-91GW059KN7, Ethene (9CI), MFCD00084423, CH2=CH2, H2C=CH2, Polyethylene(PE), EC 200-815-3, Ethylene, compressed [UN1962] [Flammable gas]
Molecular formula: C₂H₄
Empirical formula: CH₂
Molecular weight: 28.05 g/mol
Exact mass: 28.03130
CAS number: 74-85-1
PubChem CID: 6325
Canonical SMILES: C=C
Isomeric SMILES: C=C
InChI: InChI=1S/C2H4/c1-2/h1-2H2
InChIKey: VGGSQFUCUMXWEO-UHFFFAOYSA-N
Molfile

Names, InChI and the identifiers from PubChem, retrieved 2026-10-14.

Physical properties

TemperaturePressureDensity

Appearance: Colorless gas[5]
6 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source
– Ethylene appears as a colorless gas with a sweet odor and taste. It is lighter than air. It is easily ignited and a flame can easily flash back to the source of the leak. Under prolonged exposure to fire or heat the containers may rupture violently and rocket. Can cause explosion. [1] CAMEO Chemicals
– Ethylene, refrigerated liquid (cryogenic liquid) appears as a pressurized liquid when shipped below 50 °F. Colorless with a sweet odor and taste. Vapors arising from the boiling liquid are lighter than air. Easily ignited. Not toxic but is a simple asphyxiant. Under prolonged exposure to fire or intense heat the containers may rupture violently and rocket. Used as an anesthetic, a refrigerant, and to make other chemicals. [1] CAMEO Chemicals
– Gas Vapor; Gas Vapor; Liquid; Liquid [2] EPA Chemical Data Reporting (CDR)
– COLOURLESS COMPRESSED GAS WITH CHARACTERISTIC ODOUR. [3] ILO-WHO International Chemical Safety Cards (ICSCs)
– Colorless gas with a sweet odor. [4] Occupational Safety and Health Administration (OSHA)
–shown Colorless gas [5] Hazardous Substances Data Bank (HSDB)cites Larranaga, M.D., Lewis, R.J. Sr., Lewis, R.A.; Hawley's Condensed Chemical Dictionary 16th Edition. John Wiley & Sons, Inc. Hoboken, NJ 2016., p. 581
Odor: Sweet[5]
2 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source
–shown Sweet [5] Hazardous Substances Data Bank (HSDB)cites Larranaga, M.D., Lewis, R.J. Sr., Lewis, R.A.; Hawley's Condensed Chemical Dictionary 16th Edition. John Wiley & Sons, Inc. Hoboken, NJ 2016., p. 581
– Olefinic, hedonic tone: unpleasant to neutral [5] Hazardous Substances Data Bank (HSDB)cites Que Hee, S. (ed.). Biological Monitoring an Introduction. New York, NY: Van Nostrand Reinhold Co., 1993., p. 1089
Melting point: -169.15 °C[6]
4 values
4 of 4 sources agree on it (most common value).
Value As written Source
−169.1 °C -272.4 °F (USCG, 1999) [1] CAMEO Chemicalscites U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
−169.2 °C -169.2 °C [3] ILO-WHO International Chemical Safety Cards (ICSCs)
−169.1 °C -272.4 °F [4] Occupational Safety and Health Administration (OSHA)
−169.2 °Cshown -169.15 °C [6] PAC Chemical Database, U.S. Department of Energy
Boiling point: -103.77 °C @760 [mmHg][6]
4 values
4 of 4 sources agree on it (most common value).
Value As written Source
−103.7 °C -154.7 °F at 760 mmHg (USCG, 1999) [1] CAMEO Chemicalscites U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
−104 °C -104 °C [3] ILO-WHO International Chemical Safety Cards (ICSCs)
−103.7 °C -154.7 °F [4] Occupational Safety and Health Administration (OSHA)
−103.8 °Cshown -103.77 °C @760 [mm Hg] [6] PAC Chemical Database, U.S. Department of Energy
Density: 0.568 @ -104°C[6]
3 values
3 of 3 sources agree on it (most common value).
Value As written Source
– 0.569 at -154.84 °F (USCG, 1999) - Less dense than water [1] CAMEO Chemicalscites U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
– 0.569 at -154.84 °F [4] Occupational Safety and Health Administration (OSHA)
–shown 0.568 @ -104°C [6] PAC Chemical Database, U.S. Department of Energy
Solubility in water: Solubility in water, mg/l at 25 °C: 131 (very slightly soluble)[3]
4 values
From ILO-WHO International Chemical Safety Cards (ICSCs), the most authoritative source here.
Value As written Source
– In water, 131 mg/L at 25 °C [5] Hazardous Substances Data Bank (HSDB)cites McAuliffe C; J Phys Chem 70: 1267-75 (1966)
– Slightly soluble in water [5] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 12th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2012., p. V3: 2015
– Very soluble in ethanol, ether; soluble in acetone acid, benzene [5] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 12th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2012., p. V3: 2015
–shown Solubility in water, mg/l at 25 °C: 131 (very slightly soluble) [3] ILO-WHO International Chemical Safety Cards (ICSCs)
log P: 1.13[3]
2 values
2 of 2 sources agree on it (most common value).
Value As written Source
– log Kow = 1.13 [5] Hazardous Substances Data Bank (HSDB)cites Hansch, C., Leo, A., D. Hoekman. Exploring QSAR - Hydrophobic, Electronic, and Steric Constants. Washington, DC: American Chemical Society., 1995., p. 4
–shown 1.13 [3] ILO-WHO International Chemical Safety Cards (ICSCs)
Vapor pressure: 51200 [mmHg] @25 °C[6]
3 values
2 of 3 sources agree on it (most common value).
Value As written Source
52100 mmHg 5.21X10+4 mm Hg at 25 °C /Extrapolated/ [5] Hazardous Substances Data Bank (HSDB)cites Daubert, T.E., R.P. Danner. Physical and Thermodynamic Properties of Pure Chemicals Data Compilation. Washington, D.C.: Taylor and Francis, 1989.
61000 mmHg Vapor pressure, kPa at 15 °C: 8100 [3] ILO-WHO International Chemical Safety Cards (ICSCs)
51200 mmHgshown 51200 [mm Hg] @25 °C [6] PAC Chemical Database, U.S. Department of Energy
1 more value was reported but failed the checks (unreadable or out of range), so it is not shown.
Flash point: -136 °C (-213 °F) (approx.) (USCG, 1999)[1]
3 values
2 of 3 sources agree on it (most common value).
Value As written Source
−136 °Cshown -213 °F (approx.) (USCG, 1999) [1] CAMEO Chemicalscites U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
−100 °C -100 °C (-148 °F) - closed cup [5] Hazardous Substances Data Bank (HSDB)cites Sigma-Aldrich; Safety Data Sheet for Ethylene. Product Number: 536164, Version 3.7 (Revision Date 05/24/2016). Available from, as of July 26, 2017: https://www.sigmaaldrich.com/safety-center.html
−136 °C -213 °F (approx) [4] Occupational Safety and Health Administration (OSHA)
Autoignition temperature: 450 °C (842 °F)[5]
3 values
2 of 3 sources agree on it (most common value).
Value As written Source
450 °C 842 °F (USCG, 1999) [1] CAMEO Chemicalscites U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
450 °Cshown 842 °F (450 °C) [5] Hazardous Substances Data Bank (HSDB)cites National Fire Protection Association; Fire Protection Guide to Hazardous Materials. 14TH Edition, Quincy, MA 2010, p. 325-60
440 °C 440 °C [3] ILO-WHO International Chemical Safety Cards (ICSCs)
Viscosity: 0.01 mPa.s 20 °C[5]

Value	As written	Source
–	Ethylene appears as a colorless gas with a sweet odor and taste. It is lighter than air. It is easily ignited and a flame can easily flash back to the source of the leak. Under prolonged exposure to fire or heat the containers may rupture violently and rocket. Can cause explosion.	[1] CAMEO Chemicals
–	Ethylene, refrigerated liquid (cryogenic liquid) appears as a pressurized liquid when shipped below 50 °F. Colorless with a sweet odor and taste. Vapors arising from the boiling liquid are lighter than air. Easily ignited. Not toxic but is a simple asphyxiant. Under prolonged exposure to fire or intense heat the containers may rupture violently and rocket. Used as an anesthetic, a refrigerant, and to make other chemicals.	[1] CAMEO Chemicals
–	Gas Vapor; Gas Vapor; Liquid; Liquid	[2] EPA Chemical Data Reporting (CDR)
–	COLOURLESS COMPRESSED GAS WITH CHARACTERISTIC ODOUR.	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
–	Colorless gas with a sweet odor.	[4] Occupational Safety and Health Administration (OSHA)
–shown	Colorless gas	[5] Hazardous Substances Data Bank (HSDB)cites Larranaga, M.D., Lewis, R.J. Sr., Lewis, R.A.; Hawley's Condensed Chemical Dictionary 16th Edition. John Wiley & Sons, Inc. Hoboken, NJ 2016., p. 581

Value	As written	Source
–shown	Sweet	[5] Hazardous Substances Data Bank (HSDB)cites Larranaga, M.D., Lewis, R.J. Sr., Lewis, R.A.; Hawley's Condensed Chemical Dictionary 16th Edition. John Wiley & Sons, Inc. Hoboken, NJ 2016., p. 581
–	Olefinic, hedonic tone: unpleasant to neutral	[5] Hazardous Substances Data Bank (HSDB)cites Que Hee, S. (ed.). Biological Monitoring an Introduction. New York, NY: Van Nostrand Reinhold Co., 1993., p. 1089

Value	As written	Source
−169.1 °C	-272.4 °F (USCG, 1999)	[1] CAMEO Chemicalscites U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
−169.2 °C	-169.2 °C	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
−169.1 °C	-272.4 °F	[4] Occupational Safety and Health Administration (OSHA)
−169.2 °Cshown	-169.15 °C	[6] PAC Chemical Database, U.S. Department of Energy

Value	As written	Source
−103.7 °C	-154.7 °F at 760 mmHg (USCG, 1999)	[1] CAMEO Chemicalscites U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
−104 °C	-104 °C	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
−103.7 °C	-154.7 °F	[4] Occupational Safety and Health Administration (OSHA)
−103.8 °Cshown	-103.77 °C @760 [mm Hg]	[6] PAC Chemical Database, U.S. Department of Energy

Value	As written	Source
–	0.569 at -154.84 °F (USCG, 1999) - Less dense than water	[1] CAMEO Chemicalscites U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
–	0.569 at -154.84 °F	[4] Occupational Safety and Health Administration (OSHA)
–shown	0.568 @ -104°C	[6] PAC Chemical Database, U.S. Department of Energy

Value	As written	Source
–	In water, 131 mg/L at 25 °C	[5] Hazardous Substances Data Bank (HSDB)cites McAuliffe C; J Phys Chem 70: 1267-75 (1966)
–	Slightly soluble in water	[5] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 12th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2012., p. V3: 2015
–	Very soluble in ethanol, ether; soluble in acetone acid, benzene	[5] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 12th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2012., p. V3: 2015
–shown	Solubility in water, mg/l at 25 °C: 131 (very slightly soluble)	[3] ILO-WHO International Chemical Safety Cards (ICSCs)

Value	As written	Source
–	log Kow = 1.13	[5] Hazardous Substances Data Bank (HSDB)cites Hansch, C., Leo, A., D. Hoekman. Exploring QSAR - Hydrophobic, Electronic, and Steric Constants. Washington, DC: American Chemical Society., 1995., p. 4
–shown	1.13	[3] ILO-WHO International Chemical Safety Cards (ICSCs)

Value	As written	Source
52100 mmHg	5.21X10+4 mm Hg at 25 °C /Extrapolated/	[5] Hazardous Substances Data Bank (HSDB)cites Daubert, T.E., R.P. Danner. Physical and Thermodynamic Properties of Pure Chemicals Data Compilation. Washington, D.C.: Taylor and Francis, 1989.
61000 mmHg	Vapor pressure, kPa at 15 °C: 8100	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
51200 mmHgshown	51200 [mm Hg] @25 °C	[6] PAC Chemical Database, U.S. Department of Energy

Value	As written	Source
−136 °Cshown	-213 °F (approx.) (USCG, 1999)	[1] CAMEO Chemicalscites U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
−100 °C	-100 °C (-148 °F) - closed cup	[5] Hazardous Substances Data Bank (HSDB)cites Sigma-Aldrich; Safety Data Sheet for Ethylene. Product Number: 536164, Version 3.7 (Revision Date 05/24/2016). Available from, as of July 26, 2017: https://www.sigmaaldrich.com/safety-center.html
−136 °C	-213 °F (approx)	[4] Occupational Safety and Health Administration (OSHA)

Value	As written	Source
450 °C	842 °F (USCG, 1999)	[1] CAMEO Chemicalscites U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
450 °Cshown	842 °F (450 °C)	[5] Hazardous Substances Data Bank (HSDB)cites National Fire Protection Association; Fire Protection Guide to Hazardous Materials. 14TH Edition, Quincy, MA 2010, p. 325-60
440 °C	440 °C	[3] ILO-WHO International Chemical Safety Cards (ICSCs)

Each value as its source reports it, with the source's number after it (listed under References). Where several sources report a property, the row shows the value most of them agree on, the rule the app uses; open the values to see every one.

Calculated

Heavy atoms: 2
Rings: 0
Aromatic rings: 0
Fraction sp³ carbons (Fsp3): 0
H-bond donors: 0
H-bond acceptors: 0
Rotatable bonds: 0
TPSA (Å²): 0
Formal charge: 0
XLogP3: 1.2 PubChem
Complexity: 0 PubChem
Stereocenters: None
Double-bond geometry: None specified
Point group: D2h of one 3D conformer with its hydrogens, by Athanor’s engine (as in the app)

Elemental analysis

C85.63%
H14.37%

Isotope pattern

Each peak is a nominal mass with its abundance-weighted exact mass, as a percentage of the tallest, from IUPAC natural isotope abundances.

Computed from the structure with RDKit 2026.09 when this page was built, beside PubChem's own computed values from its record; where the two differ, both are shown.

Predicted

log P: 0.8 Crippen (Wildman and Crippen 1999)
log S (water solubility): -0.52 ESOL (Delaney 2004), log mol/L
Synthetic accessibility: 4.09 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)

Drug-likeness: Lipinski’s rule of five

Molecular weight ≤ 500: 28.05
log P ≤ 5 (Crippen): 0.8
H-bond donors ≤ 5: 0
H-bond acceptors ≤ 10: 0

Passes all four rules.

¹³C NMR shifts, predicted

Predictions, not measurements; each names its method. A measured log P, where a source reports one, is under Physical properties.

Safety

Danger

Harmonized EU classification (CLP Annex VI). Source [7].

Flammable
Compressed gas
Harmful or irritant

NFPA 704[5]

H220Extremely flammable gas
H336May cause drowsiness or dizziness

Precautionary statements: P203, P210, P222, P261, P271, P280, P304+P340, P319, P377, P381, P403, P403+P233, P405, P501

View all classifications (5)

[7] Regulation (EC) No 1272/2008 of the European Parliament and of the Council · DangerH220, H336
[8] European Chemicals Agency (ECHA)This chemical does not meet GHS hazard criteria for 0.8% (38 of 4869) of reports.
[8] European Chemicals Agency (ECHA) · 4,869 reports · DangerH220, H280, H336
[8] European Chemicals Agency (ECHA) · 2 reportsThis chemical does not meet GHS hazard criteria for 100% (2 of 2) of all reports.
[5] Hazardous Substances Data Bank (HSDB) · DangerH220, H280, H336

Exposure limits

TLV: 200 ppm as TWA; A4 (not classifiable as a human carcinogen).[3]
TLV-TWA (Time Weighted Average): 200 ppm [2001][4]
MAK (Maximale Arbeitsplatz Konzentration): Carcinogen category: 3[3]

First aid

Remove victim to fresh air, give artificial respiration and oxygen if breathing has stopped, and call a physician. (USCG, 1999)[1]
Excerpt from ERG Guide 115 [Gases - Flammable (Including Refrigerated Liquids)]: Refer to the "General First Aid" section. Specific First Aid: Clothing frozen to the skin should be thawed before being removed. In case of contact with liquefied gas, only medical personnel should attempt thawing frosted parts. In case of burns, immediately cool affected skin for as long as possible with cold water. Do not remove clothing if adhering to skin. (ERG, 2024)[1]
General First Aid: · Call 911 or emergency medical service. · Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination. · Move victim to fresh air if it can be done safely. · Administer oxygen if breathing is difficult. · If victim is not breathing: -- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance. -- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped…[9]
General First Aid: · Call 911 or emergency medical service. · Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination. · Move victim to fresh air if it can be done safely. · Administer oxygen if breathing is difficult. · If victim is not breathing: -- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance. -- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped…[9]

Storage

Fireproof. Separated from strong oxidants.[3]
Store in cool dry, well-ventilated location. Protect against static electricity and lightning. Isolate from oxidizing materials, halogens, and other combustibles.[5]
Keep container tightly closed in a dry and well-ventilated place. Contents under pressure. Storage class (TRGS 510): Gases[5]
Protect containers against physical damage. Outdoor or detached storage is preferred. For indoor storage, use a fireproof, well-ventilated, area isolated from any sources of ignition.[5]

Incompatibilities

Incompatible materials: Strong oxidizing agents, carbon tetrachloride, chlorine, copper, vinyl compounds.[5]
Reacts vigorously with oxidizing materials.[5]
In absence of nitrogen as a diluent, interaction with (trifluoromethyl hypofluorite) ... (and) ethylene is explosive on mixing.[5]
Explosive reaction with chlorine is possible.[5]

Safety data sheets on the supplier’s page: Hunan Chemfish Pharmaceutical Co., Ltd., abcr GmbH, Aladdin Scientific.

Always read the supplier’s safety data sheet before working with it.

Spectra

13C NMRHazardous Substances Data Bank (HSDB) · SpectraBase (BRUKER HX-90)
GC-MSNIST Mass Spectrometry Data Center · NIST Mass Spectrometry Data Center · SpectraBase
Other MSHazardous Substances Data Bank (HSDB)
UVHazardous Substances Data Bank (HSDB)
IRHazardous Substances Data Bank (HSDB)
Vapor Phase IRSpectraBase (DIGILAB FTS-14 · Vapor Phase)

Experimental spectra held by these sources; each link opens the source's own record.

Literature

Reading PubChem, OpenAlex and GSRS…

Bioactivity

Reading ChEMBL…

References

[1]CAMEO Chemicals · Public domain (NOAA) · via PubChem · retrieved 2026-10-14
[2]EPA Chemical Data Reporting (CDR) · Public domain (US EPA) · via PubChem · retrieved 2026-10-14
[3]ILO-WHO International Chemical Safety Cards (ICSCs) · CC BY 4.0 · via PubChem · retrieved 2026-10-14
[4]Occupational Safety and Health Administration (OSHA) · Public domain (US DOL) · via PubChem · retrieved 2026-10-14
[5]Hazardous Substances Data Bank (HSDB) · Public domain (US NLM) · via PubChem · retrieved 2026-10-14
[6]PAC Chemical Database, U.S. Department of Energy · Public domain (US DOE) · via PubChem · retrieved 2026-10-14
[7]Regulation (EC) No 1272/2008 of the European Parliament and of the Council · EU reuse policy, CC BY 4.0 · via PubChem · retrieved 2026-10-14
[8]European Chemicals Agency (ECHA) · ECHA legal notice: reuse with acknowledgement · via PubChem · retrieved 2026-10-14
[9]Emergency Response Guidebook (ERG) · Public domain (US DOT) · via PubChem · retrieved 2026-10-14
[10]SpectraBase · Linked only · via PubChem · retrieved 2026-10-14
[11]NIST Mass Spectrometry Data Center · Linked only · via PubChem · retrieved 2026-10-14
·Calculated values: computed by Athanor with RDKit 2026.09 from the structure.
·Literature on PubChem

Data last updated 2026-10-14.