Ozone

Athanor · official

O₃ · 47.998 g/mol

Also called trioxygen, O3

Inorganic

Open in Athanor

Drawn from its SMILES with RDKit

DangerMay cause or intensify fire; oxidizer · Causes severe skin burns and eye damage · Causes skin irritation · Causes serious eye damage · Causes serious eye irritation · Fatal if inhaled · May cause respiratory irritation · Suspected of causing genetic defects · Causes damage to organs through prolonged or repeated exposure · May causes damage to organs through prolonged or repeated exposure · Very toxic to aquatic life · Very toxic to aquatic life with long lasting effects

Names and identifiers

IUPAC name: ozone
Synonyms: trioxygen, O3, Triatomic oxygen
+ 35 more
Ozon, Ozone heavy work, ozono, Oxygen, mol (O3), trioxygene, 66H7ZZK23N, DTXSID0021098, CHEBI:25812, Low Level Ozone, Level Ozone, Low, Ozone, Low Level, Ozone, Tropospheric, Level Ozone, Ground, Ozone, Ground Level, RefChem:6092, DTXCID001098, 233-069-2, 629-936-3, Ozon [Polish], Ground Level Ozone, CCRIS 4503, HSDB 717, EINECS 233-069-2, UNII-66H7ZZK23N, Trisauerstoff, OZONE [HSDB], OZONE [FCC], OZONE [WHO-DD], OZONE [MI], SCHEMBL17235, CHEMBL2447938, [OO2], DB12510, NS00076141, Q36933
Molecular formula: O₃
Empirical formula: O
Molecular weight: 47.998 g/mol
Exact mass: 47.98474
CAS number: 10028-15-6
PubChem CID: 24823
Canonical SMILES: [O-][O+]=O
Isomeric SMILES: [O-][O+]=O
InChI: InChI=1S/O3/c1-3-2
InChIKey: CBENFWSGALASAD-UHFFFAOYSA-N
Molfile

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

Physical properties

TemperaturePressureDensity

Appearance: Colorless to blue gas.[6]
6 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source
– Ozone appears as a colorless to bluish gas that condenses to a dark blue liquid, or blue-black crystals. Has a characteristic odor in concentrations less than 2 ppm. Used as a disinfectant for air and water; used for bleaching waxes, textiles and oils, ozonolysis of unsaturated fatty acids to pelargonic and other acids; manufacture of ink; catalyst; water treatment for taste and odor control; mold and bacteria inhibitor in cold storage; bleaching agent. (EPA, 1998) [1] CAMEO Chemicalscites U.S. Environmental Protection Agency. 1998. Extremely Hazardous Substances (EHS) Chemical Profiles and Emergency First Aid Guides. Washington, D.C.: U.S. Government Printing Office.
– Gas Vapor [2] EPA Chemical Data Reporting (CDR)
– COLOURLESS OR BLUISH GAS WITH CHARACTERISTIC ODOUR. [3] ILO-WHO International Chemical Safety Cards (ICSCs)
– Colorless to blue gas with a very pungent odor. [4] Occupational Safety and Health Administration (OSHA)
– Colorless to blue gas with a very pungent odor. [5] The National Institute for Occupational Safety and Health (NIOSH)
–shown Colorless to blue gas. [6] Hazardous Substances Data Bank (HSDB)cites NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 94-116. Washington, D.C.: U.S. Government Printing Office, June 1994., p. 238
Odor: Pungent odor[6]
2 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source
–shown Pungent odor [6] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J., Sr (Ed.). Hawley's Condensed Chemical Dictionary. 12th ed. New York, NY: Van Nostrand Rheinhold Co., 1993, p. 864
– Very pungent odor. [6] Hazardous Substances Data Bank (HSDB)cites NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 94-116. Washington, D.C.: U.S. Government Printing Office, June 1994., p. 238
Melting point: -193 °C[3]
5 values
5 of 5 sources agree on it (most common value).
Value As written Source
−192 °C -314 °F (EPA, 1998) [1] CAMEO Chemicalscites U.S. Environmental Protection Agency. 1998. Extremely Hazardous Substances (EHS) Chemical Profiles and Emergency First Aid Guides. Washington, D.C.: U.S. Government Printing Office.
−193 °Cshown -193 °C [3] ILO-WHO International Chemical Safety Cards (ICSCs)
−193 °C -315 °F [4] Occupational Safety and Health Administration (OSHA)
−193 °C -193 °C [7] PAC Chemical Database, U.S. Department of Energy
−193 °C -315 °F [5] The National Institute for Occupational Safety and Health (NIOSH)
Boiling point: -111.35 °C @760 [mmHg][7]
5 values
5 of 5 sources agree on it (most common value).
Value As written Source
−112.0 °C -169.6 °F at 760 mmHg (EPA, 1998) [1] CAMEO Chemicalscites U.S. Environmental Protection Agency. 1998. Extremely Hazardous Substances (EHS) Chemical Profiles and Emergency First Aid Guides. Washington, D.C.: U.S. Government Printing Office.
−112 °C -112 °C [3] ILO-WHO International Chemical Safety Cards (ICSCs)
−112 °C -169 °F [4] Occupational Safety and Health Administration (OSHA)
−111.3 °Cshown -111.35 °C @760 [mm Hg] [7] PAC Chemical Database, U.S. Department of Energy
−112 °C -169 °F [5] The National Institute for Occupational Safety and Health (NIOSH)
Density: 1.614 at -195.4 °C (-319.7 °F) (NTP, 1992) - Denser than water[1]
4 values
3 of 4 sources agree on it (most common value).
Value As written Source
–shown 1.614 at -319.7 °F (NTP, 1992) - Denser than water [1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
– 1.614 at -319.7 °F [4] Occupational Safety and Health Administration (OSHA)
– 1.962 @25 °C [7] PAC Chemical Database, U.S. Department of Energy
– 1.66(relative gas density) [5] The National Institute for Occupational Safety and Health (NIOSH)
Solubility in water: Solubility in water: none[3]
3 values
From ILO-WHO International Chemical Safety Cards (ICSCs), the most authoritative source here.
Value As written Source
– 3e-05 g/100 g at 68 °F (NTP, 1992) [1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
–shown Solubility in water: none [3] ILO-WHO International Chemical Safety Cards (ICSCs)
– (32 °F): 0.001% [5] The National Institute for Occupational Safety and Health (NIOSH)
Vapor pressure: 41257 mmHg at -12.0 °C (10.4 °F, EPA 1998)[1]
2 values
Sources disagree; from CAMEO Chemicals, the most authoritative.
Value As written Source
41257 mmHgshown 41257 mmHg at 10.4 °F (EPA, 1998) [1] CAMEO Chemicalscites U.S. Environmental Protection Agency. 1998. Extremely Hazardous Substances (EHS) Chemical Profiles and Emergency First Aid Guides. Washington, D.C.: U.S. Government Printing Office.
750 mmHg 750 [mm Hg] @-111.5 °C [7] PAC Chemical Database, U.S. Department of Energy
2 more values were reported but failed the checks (unreadable or out of range), so they are not shown.

Value	As written	Source
–	Ozone appears as a colorless to bluish gas that condenses to a dark blue liquid, or blue-black crystals. Has a characteristic odor in concentrations less than 2 ppm. Used as a disinfectant for air and water; used for bleaching waxes, textiles and oils, ozonolysis of unsaturated fatty acids to pelargonic and other acids; manufacture of ink; catalyst; water treatment for taste and odor control; mold and bacteria inhibitor in cold storage; bleaching agent. (EPA, 1998)	[1] CAMEO Chemicalscites U.S. Environmental Protection Agency. 1998. Extremely Hazardous Substances (EHS) Chemical Profiles and Emergency First Aid Guides. Washington, D.C.: U.S. Government Printing Office.
–	Gas Vapor	[2] EPA Chemical Data Reporting (CDR)
–	COLOURLESS OR BLUISH GAS WITH CHARACTERISTIC ODOUR.	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
–	Colorless to blue gas with a very pungent odor.	[4] Occupational Safety and Health Administration (OSHA)
–	Colorless to blue gas with a very pungent odor.	[5] The National Institute for Occupational Safety and Health (NIOSH)
–shown	Colorless to blue gas.	[6] Hazardous Substances Data Bank (HSDB)cites NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 94-116. Washington, D.C.: U.S. Government Printing Office, June 1994., p. 238

Value	As written	Source
–shown	Pungent odor	[6] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J., Sr (Ed.). Hawley's Condensed Chemical Dictionary. 12th ed. New York, NY: Van Nostrand Rheinhold Co., 1993, p. 864
–	Very pungent odor.	[6] Hazardous Substances Data Bank (HSDB)cites NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 94-116. Washington, D.C.: U.S. Government Printing Office, June 1994., p. 238

Value	As written	Source
−192 °C	-314 °F (EPA, 1998)	[1] CAMEO Chemicalscites U.S. Environmental Protection Agency. 1998. Extremely Hazardous Substances (EHS) Chemical Profiles and Emergency First Aid Guides. Washington, D.C.: U.S. Government Printing Office.
−193 °Cshown	-193 °C	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
−193 °C	-315 °F	[4] Occupational Safety and Health Administration (OSHA)
−193 °C	-193 °C	[7] PAC Chemical Database, U.S. Department of Energy
−193 °C	-315 °F	[5] The National Institute for Occupational Safety and Health (NIOSH)

Value	As written	Source
−112.0 °C	-169.6 °F at 760 mmHg (EPA, 1998)	[1] CAMEO Chemicalscites U.S. Environmental Protection Agency. 1998. Extremely Hazardous Substances (EHS) Chemical Profiles and Emergency First Aid Guides. Washington, D.C.: U.S. Government Printing Office.
−112 °C	-112 °C	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
−112 °C	-169 °F	[4] Occupational Safety and Health Administration (OSHA)
−111.3 °Cshown	-111.35 °C @760 [mm Hg]	[7] PAC Chemical Database, U.S. Department of Energy
−112 °C	-169 °F	[5] The National Institute for Occupational Safety and Health (NIOSH)

Value	As written	Source
–shown	1.614 at -319.7 °F (NTP, 1992) - Denser than water	[1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
–	1.614 at -319.7 °F	[4] Occupational Safety and Health Administration (OSHA)
–	1.962 @25 °C	[7] PAC Chemical Database, U.S. Department of Energy
–	1.66(relative gas density)	[5] The National Institute for Occupational Safety and Health (NIOSH)

Value	As written	Source
–	3e-05 g/100 g at 68 °F (NTP, 1992)	[1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
–shown	Solubility in water: none	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
–	(32 °F): 0.001%	[5] The National Institute for Occupational Safety and Health (NIOSH)

Value	As written	Source
41257 mmHgshown	41257 mmHg at 10.4 °F (EPA, 1998)	[1] CAMEO Chemicalscites U.S. Environmental Protection Agency. 1998. Extremely Hazardous Substances (EHS) Chemical Profiles and Emergency First Aid Guides. Washington, D.C.: U.S. Government Printing Office.
750 mmHg	750 [mm Hg] @-111.5 °C	[7] PAC Chemical Database, U.S. Department of Energy

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: 3
Rings: 0
Aromatic rings: 0
Fraction sp³ carbons (Fsp3): 0
H-bond donors: 0
H-bond acceptors: 2
Rotatable bonds: 0
TPSA (Å²): 51.4 computed here · PubChem 41.1
Formal charge: 0
XLogP3: -1.7 PubChem
Complexity: 4 PubChem
Stereocenters: None
Double-bond geometry: None specified
Point group: C2v of one 3D conformer with its hydrogens, by Athanor’s engine (as in the app)

Elemental analysis

O100.00%

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: -1.12 Crippen (Wildman and Crippen 1999)
log S (water solubility): 0.57 ESOL (Delaney 2004), log mol/L
Synthetic accessibility: 6.05 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)

Drug-likeness: Lipinski’s rule of five

Molecular weight ≤ 500: 48
log P ≤ 5 (Crippen): -1.12
H-bond donors ≤ 5: 0
H-bond acceptors ≤ 10: 2

Passes all four rules.

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

Safety

Danger

Most widely reported: 262 company reports to ECHA. Source [8].

Oxidizer
Corrosive
Acute toxicity
Harmful or irritant
Health hazard
Environmental hazard

H270May cause or intensify fire; oxidizer (99.6% of reports)
H314Causes severe skin burns and eye damage (43.9% of reports)
H315Causes skin irritation (37% of reports)
H318Causes serious eye damage (43.9% of reports)
H319Causes serious eye irritation (55.7% of reports)
H330Fatal if inhaled (99.6% of reports)
H335May cause respiratory irritation (37% of reports)
H341Suspected of causing genetic defects (21.4% of reports)
H372Causes damage to organs through prolonged or repeated exposure (43.9% of reports)
H373May causes damage to organs through prolonged or repeated exposure (21.4% of reports)
H400Very toxic to aquatic life (80.9% of reports)
H410Very toxic to aquatic life with long lasting effects (44.3% of reports)

Precautionary statements: P203, P220, P244, P260, P261, P264, P264+P265, P270, P271, P273, P280, P284, P301+P330+P331, P302+P352, P302+P361+P354, P304+P340, P305+P351+P338, P305+P354+P338, P316, P317, P318, P319, P320, P321, P332+P317, P337+P317, P362+P364, P363, P370+P376, P391, P403, P403+P233, P405, P501

Exposure limits

PEL-TWA (8-Hour Time Weighted Average): 0.1 ppm (0.2 mg/m³)[4]
PEL: TWA 0.1 ppm (0.2 mg/m3) See Appendix G[5]
REL: C 0.1 ppm (0.2 mg/m3)[5]
TLV: (light work): 0.1 ppm as TWA; (moderate work): 0.08 ppm as TWA; (heavy work): 0.05 ppm as TWA.[3]
TLV-TWA (Time Weighted Average): Heavy work: 0.05 ppm (0.10 mg/m³), Moderate work: 0.08 ppm (0.16 mg/m³), Light work: 0.10 ppm (0.20 mg/m³) [1995][4]
IDLH: 5 ppm (NIOSH, 2024)[1]

First aid

Warning: Effects may be delayed for 12 to 24 hours. Caution is advised. Signs and Symptoms of Acute Ozone Exposure: Signs and symptoms of acute exposure to ozone may be severe and include irritation and burns of the skin, eyes, and mucous membranes. An increased respiratory rate, shallow breathing, cough, dyspnea (shortness of breath), bronchitis, pulmonary edema, and pulmonary hemorrhage may occur. Tachycardia (rapid heart rate) and hypotension (low blood pressure) may be observed. Neurologic effects include fatigue, dizziness, drowsiness, headache, exhiliration, and depression.[1]
(General first aid procedures) Eye: Medical attention - Self-explanatory Breathing: Fresh air; 100% O2[5]
Fresh air, rest. Half-upright position. Refer for medical attention.[3]
ON frostbite: Rinse with plenty of water, do NOT remove clothes. Refer for medical attention .[3]

Storage

Fireproof if in building. Separated from all substances. Cool.[3]
Cylinders OF dissolved ozone should BE stored IN refrigerated areas & AWAY FROM ALL reducing agents, flammable materials & substances SUCH AS IRON, copper OR chromium THAT MAY catalyze decomp.[6]
Store in well-ventilated, cool, dark places. Detached storage is preferred. Avoid storage near combustible materials.[6]

Incompatibilities

All oxidizable materials (both organic and inorganic).[6]
Explosive with alkenes, aromatic compounds, bromine, combustible gasses, diethyl ether, hydrogen bromide, isopropylidene compounds.[6]
Dangerous (fire hazard) by chemical reaction with aniline, benzene, bromide, (diallyl methyl carbinol + acetic acid), diethyl ether, nitrogen pentoxide, ethylene, hydrogen bromide, hydrogen iodide, nitrogen dioxide, nitric oxide, nitrogen chloride, NI3, nitroglycerin, organic liquids, organic matter, antimony.[6]
(other) incompatabilities: Alkenes, aromatic compounds, rubber, dicyanogen, dinitrogen tetroxide, 4-hydroxy-4-methyl-1,6-heptadiene, nitrogen trichloride, stibine, tetrafluorohydrazine.[6]

Safety data sheets on the supplier’s page: EvitaChem, CymitQuimica, BenchChem.

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

Spectra

17O NMRSpectraBase

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]The National Institute for Occupational Safety and Health (NIOSH) · Public domain (US CDC) · via PubChem · retrieved 2026-10-14
[6]Hazardous Substances Data Bank (HSDB) · Public domain (US NLM) · via PubChem · retrieved 2026-10-14
[7]PAC Chemical Database, U.S. Department of Energy · Public domain (US DOE) · via PubChem · retrieved 2026-10-14
[8]European Chemicals Agency (ECHA) · ECHA legal notice: reuse with acknowledgement · via PubChem · retrieved 2026-10-14
[9]SpectraBase · 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.