Caprylic acid
Athanor · official
C8H16O2 · 144.21 g/mol
IUPAC name: octanoic acid
Also called octanoic acid, C8:0, caprylate
DangerCauses severe skin burns and eye damage · Harmful to aquatic life with long lasting effectsNames and identifiers
- IUPAC name
- octanoic acid
- Synonyms
- octanoic acid, C8:0, caprylate
+ 37 more
n-octanoic acid, n-caprylic acid, Octylic acid, octoic acid, n-octylic acid, 1-heptanecarboxylic acid, n-Octoic acid, Enantic acid, Octic acid, C-8 acid, Caprylsaeure, Acido octanoico, Acide octanoique, Kaprylsaeure, Hexacid 898, FEMA No. 2799, Acidum octanocium, Kyselina kaprylova, Octansaeure, NSC-5024, Kortacid-0899, Emery 657, Prifac 2901, Prifac-2901, DTXSID3021645, Lunac 8-95, acidum octanoicum, EDENOR C 8-98-100, OBL58JN025, Kortacid 0899, n-octic acid, CHEBI:28837, Lunac 8-98, DTXCID501645, hydron;octanoate, fatty acid 8:0, RefChem:57810
- Molecular formula
- C8H16O2
- Empirical formula
- C4H8O
- Molecular weight
- 144.21 g/mol
- Exact mass
- 144.11503
- CAS number
- 124-07-2
- PubChem CID
- 379
- Canonical SMILES
- CCCCCCCC(=O)O
- Isomeric SMILES
- CCCCCCCC(=O)O
- InChI
- InChI=1S/C8H16O2/c1-2-3-4-5-6-7-8(9)10/h2-7H2,1H3,(H,9,10)
- InChIKey
- WWZKQHOCKIZLMA-UHFFFAOYSA-N
- Molfile
Names, InChI and the identifiers from PubChem, retrieved 2026-10-14.
Physical properties
TemperaturePressureDensity
- Appearance
- Colorless[3]
3 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source – Octanoic acid appears as a colorless to light yellow liquid with a mild odor. Burns, but may be difficult to ignite. Corrosive to metals and tissue. [1] CAMEO Chemicals – Liquid; Liquid; Other Solid [2] EPA Chemical Data Reporting (CDR) –shown Colorless [3] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 14th Edition. John Wiley & Sons, Inc. New York, NY 2001., p. 286 - Odor
- Slight odor[3]
3 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source – FAINT, FRUITY-ACID ODOR [3] Hazardous Substances Data Bank (HSDB)cites Fenaroli's Handbook of Flavor Ingredients. Volume 2. Edited, translated, and revised by T.E. Furia and N. Bellanca. 2nd ed. Cleveland: The Chemical Rubber Co., 1975., p. 442 – UNPLEASANT AND IRRITATING ODOR [3] Hazardous Substances Data Bank (HSDB)cites Patty, F. (ed.). Industrial Hygiene and Toxicology: Volume II: Toxicology. 2nd ed. New York: Interscience Publishers, 1963., p. 1787 –shown Slight odor [3] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 14th Edition. John Wiley & Sons, Inc. New York, NY 2001., p. 812 - Melting point
- 16 to 17 °C (61 to 62 °F, NTP 1992)[1]
- Boiling point
- 239.7 °C (463.5 °F) at 760 mmHg (NTP, 1992)[1]
2 values
2 of 2 sources agree on it (most common value).
Value As written Source 239.7 °Cshown 463.5 °F at 760 mmHg (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. 240 °C 240 °C @760 [mm Hg] [4] PAC Chemical Database, U.S. Department of Energy - Density
- 0.91 @ 20°C[4]
2 values
2 of 2 sources agree on it (most common value).
Value As written Source – 0.91 (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. –shown 0.91 @ 20°C [4] PAC Chemical Database, U.S. Department of Energy - Solubility in water
- In water 789 mg/L at 30 °C[3]
2 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source – less than 1 mg/mL at 64 °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 In water 789 mg/L at 30 °C [3] Hazardous Substances Data Bank (HSDB)cites Yalkowsky SH, Dannenfelser RM; Aquasol Database of Aqueous Solubility. Version 5. College of Pharmacy, Univ of Ariz - Tucson, AZ. PC Version (1992) - log P
- log Kow = 3.05[3]
- pKa
- pKa = 4.895 at 25 °C[3]
- Vapor pressure
- VP: 1 MM HG AT 78.0 °C[3]
5 values
2 of 2 sources agree on it (most common value).
Value As written Source 1 mmHg 1 mmHg at 198.1 °F [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. 5 mmHg 5 mmHg at 237.4 °F [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. 760 mmHg 760 mmHg at 459.5 °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. 1 mmHgshown VP: 1 MM HG AT 78.0 °C [3] Hazardous Substances Data Bank (HSDB)cites Patty, F. (ed.). Industrial Hygiene and Toxicology: Volume II: Toxicology. 2nd ed. New York: Interscience Publishers, 1963., p. 1786 0.00371 mmHg 3.71X10-3 mm Hg at 25 °C [3] 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. - Flash point
- 130 °C (open cup)[3]
3 values
Sources disagree; from Hazardous Substances Data Bank (HSDB), the most authoritative.
Value As written Source 110 °C 230 °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. 130 °Cshown 130 °C (open cup) [3] Hazardous Substances Data Bank (HSDB)cites European Chemicals Bureau; IUCLID Dataset, Ocanoic acid (CAS # 124-07-2) p.8 (2000 CD-ROM edition). Available from, as of January 17, 2004: https://esis.jrc.ec.europa.eu/ 132 °C 270 °F. [3] Hazardous Substances Data Bank (HSDB)cites Hawley, G.G. The Condensed Chemical Dictionary. 9th ed. New York: Van Nostrand Reinhold Co., 1977., p. 631 - Viscosity
- Reported, but no value passed the checks.
The value and why
- 5.74 mPa.sec (could not be read; source [3])
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
- 10
- Rings
- 0
- Aromatic rings
- 0
- Fraction sp³ carbons (Fsp3)
- 0.88
- H-bond donors
- 1
- H-bond acceptors
- 1 computed here · PubChem 2
- Rotatable bonds
- 6
- TPSA (Ų)
- 37.3
- Formal charge
- 0
- XLogP3
- 3 PubChem
- Complexity
- 89 PubChem
- Stereocenters
- None
- Double-bond geometry
- None specified
- Point group
- C1 of one 3D conformer with its hydrogens, by Athanor’s engine (as in the app)
Elemental analysis
- C66.63%
- H11.18%
- O22.19%
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
- 2.43 Crippen (Wildman and Crippen 1999)
- log S (water solubility)
- -1.87 ESOL (Delaney 2004), log mol/L
- Synthetic accessibility
- 1.48 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)
Drug-likeness: Lipinski’s rule of five
- Molecular weight ≤ 500: 144.21
- log P ≤ 5 (Crippen): 2.43
- H-bond donors ≤ 5: 1
- H-bond acceptors ≤ 10: 1
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 [5].
- Corrosive
- H314Causes severe skin burns and eye damage
- H412Harmful to aquatic life with long lasting effects
Precautionary statements: P260, P264, P273, P280, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P321, P363, P405, P501
View all classifications (3)
- [5] Regulation (EC) No 1272/2008 of the European Parliament and of the Council · DangerH314, H412
- [6] European Chemicals Agency (ECHA)This chemical does not meet GHS hazard criteria for 2.4% (71 of 2978) of reports.
- [6] European Chemicals Agency (ECHA) · 2,978 reports · DangerH302, H311, H314, H318, H412
First aid
- Eyes: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. Immediately transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop. Skin: Immediately flood affected skin with water while removing and isolating all contaminated clothing.[1]
Storage
- Containers less than 1 gallon: Store in original container in areas inaccessible to children and persons unfamiliar with its proper use. Containers greater than 1 gallon: Do not contaminate water, food, feed by storage or disposal. ... Store this product in a cool, dry area, away from direct sunlight and heat../65 Disinfecting Heavy Duty Acid Bathroom Cleaner/[3]
Safety data sheets on the supplier’s page: Biorbyt, Acmec Biochemical, AbaChemScene.
Always read the supplier’s safety data sheet before working with it.
Spectra
- NMRHazardous Substances Data Bank (HSDB)
- 1H NMRHuman Metabolome Database (HMDB) (Varian · 500 MHz · Water) · Human Metabolome Database (HMDB) (JEOL · 90 MHz · CDCl3) · Human Metabolome Database (HMDB) (Bruker · CDCl3) · SpectraBase
- 13C NMRHuman Metabolome Database (HMDB) (Varian · 25.16 MHz · CDCl3) · Human Metabolome Database (HMDB) (Bruker · CDCl3) · SpectraBase
- 1H-13C NMRHuman Metabolome Database (HMDB) (Bruker · 600 MHz · CD3OD)
- GC-MSHuman Metabolome Database (HMDB) (EI-B · positive) · Human Metabolome Database (HMDB) (EI-B · positive) · Human Metabolome Database (HMDB) (GC-EI-TOF · positive) · Human Metabolome Database (HMDB) (GC-MS) · Human Metabolome Database (HMDB) (GC-EI-TOF · positive) · Human Metabolome Database (HMDB) (GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) · Positive)
- MS-MSHuman Metabolome Database (HMDB) (DI-ESI-Q-Exactive Plus · Negative) · Human Metabolome Database (HMDB) (EI-B (HITACHI M-80B) · Positive) · Human Metabolome Database (HMDB) (LC-ESI-QQ (API3000, Applied Biosystems) · Negative) · Human Metabolome Database (HMDB) (Negative) · Human Metabolome Database (HMDB) (Negative) · Human Metabolome Database (HMDB) (Negative)
- LC-MSMassBank Europe (API3000, Applied Biosystems · LC-ESI-QQ · NEGATIVE) · MassBank Europe (API3000, Applied Biosystems · LC-ESI-QQ · NEGATIVE) · MassBank Europe (LTQ XL, Thermo Finnigan · LC-ESI-IT · NEGATIVE) · MassBank of North America (MoNA) (LTQ XL, Thermo Finnigan · LC-ESI-IT · ESI) · MassBank of North America (MoNA) (Thermo Q Exactive HF · LC-ESI-QFT · negative) · MassBank of North America (MoNA) (Thermo Q Exactive HF · LC-ESI-QFT · negative)
- Other MSHazardous Substances Data Bank (HSDB) · MassBank Europe (HITACHI M-80B · EI-B · POSITIVE) · MassBank Europe (GCMS-2010 Plus, Shimadzu · EI-B · POSITIVE) · MassBank of North America (MoNA) (Orbitrap · negative) · MassBank of North America (MoNA) (Orbitrap · positive) · MassBank of North America (MoNA) (Orbitrap · positive)
- IRHazardous Substances Data Bank (HSDB)
- FTIRSpectraBase (NEAT (KBr))
- ATR-IRSpectraBase (Bruker Tensor 27 FT-IR · ATR-Neat (DuraSamplIR II))
- Near IRSpectraBase (BRUKER IFS 88 · NIR Spectrometer= INSTRUMENT PARAMETERS=INST=BRUKER,RSN=8877,REO=2,CNM=HEI,ZFF=2)
- Vapor Phase IRSpectraBase (DIGILAB FTS-14 · Vapor Phase)
- RamanHazardous Substances Data Bank (HSDB) · SpectraBase (Bruker MultiRAM Stand Alone FT-Raman Spectrometer · FT-Raman)
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]Hazardous Substances Data Bank (HSDB) · Public domain (US NLM) · via PubChem · retrieved 2026-10-14
- [4]PAC Chemical Database, U.S. Department of Energy · Public domain (US DOE) · via PubChem · retrieved 2026-10-14
- [5]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
- [6]European Chemicals Agency (ECHA) · ECHA legal notice: reuse with acknowledgement · via PubChem · retrieved 2026-10-14
- [7]Human Metabolome Database (HMDB) · Linked only · via PubChem · retrieved 2026-10-14
- [8]SpectraBase · Linked only · via PubChem · retrieved 2026-10-14
- [9]MassBank Europe · Linked only · via PubChem · retrieved 2026-10-14
- [10]MassBank of North America (MoNA) · CC BY 4.0 · 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.