Names | |
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Preferred IUPAC name
Hexadecanoic acid
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Other names
Palmitic acid
C16:0 (Lipid numbers) |
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Identifiers | |
57-10-3 | |
3D model (Jmol) | Interactive image |
ChEMBL | ChEMBL82293 |
ChemSpider | 960 |
ECHA InfoCard | 100.000.284 |
1055 | |
PubChem | 985 |
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Properties | |
C16H32O2 | |
Molar mass | 256.43 g·mol−1 |
Appearance | white crystals |
Density | 0.852 g/cm3 (25 °C) 0.8527 g/cm3 (62 °C) |
Melting point | 62.9 °C (145.2 °F; 336.0 K) |
Boiling point | 351–352 °C (664–666 °F; 624–625 K) 271.5 °C (520.7 °F; 544.6 K) at 100 mmHg 215 °C (419 °F; 488 K) at 15 mmHg |
0.46 mg/L (0 °C) 0.719 mg/L (20 °C) 0.826 mg/L (30 °C) 0.99 mg/L (45 °C) 1.18 mg/L (60 °C) |
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Solubility | soluble in amyl acetate, alcohol, CCl4,C6H6 very soluble in CHCl3 |
Solubility in ethanol | 2 g/100 mL (0 °C) 2.8 g/100 mL (10 °C) 9.2 g/100 mL (20 °C) 31.9 g/100 mL (40 °C) |
Solubility in methyl acetate | 7.81 g/100 g |
Solubility in ethyl acetate | 10.7 g/100 g |
Vapor pressure | 0.051 mPa (25 °C) 1.08 kPa (200 °C) 28.06 kPa (300 °C) |
Acidity (pKa) | 4.75 |
-198.6·10−6 cm3/mol | |
Refractive index (nD)
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1.43 (70 °C) |
Viscosity | 7.8 cP (70 °C) |
Thermochemistry | |
463.36 J/mol·K | |
Std molar
entropy (S |
452.37 J/mol·K |
Std enthalpy of
formation (ΔfH |
-892 kJ/mol |
Std enthalpy of
combustion (ΔcH |
10030.6 kJ/mol |
Hazards | |
GHS pictograms | |
GHS signal word | Warning |
H319 | |
P305+351+338 | |
EU classification (DSD)
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Xi |
R-phrases | R36/37/38 |
S-phrases | S26 |
NFPA 704 | |
Flash point | 206 °C (403 °F; 479 K) |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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what is ?) | (|
Infobox references | |
Palmitic acid, or hexadecanoic acid in IUPAC nomenclature, is the most common saturated fatty acid found in animals, plants and microorganisms. Its chemical formula is CH3(CH2)14COOH. As its name indicates, it is a major component of the oil from the fruit of oil palms (palm oil). Palmitic acid can also be found in meats, cheeses, butter, and dairy products. Palmitate is a term for the salts and esters of palmitic acid. The palmitate anion is the observed form of palmitic acid at physiologic pH (7.4).
Aluminium salts of palmitic acid and naphthenic acid were combined during World War II to produce napalm. The word "napalm" is derived from the words naphthenic acid and palmitic acid.
Palmitic acid was discovered by Edmond Frémy in 1840, in saponified palm oil. This remains the primary industrial route for its production, with the triglycerides (fats) in palm oil being hydrolysed by high temperature water (above 200 °C or 390 °F), and the resulting mixture fractionally distilled to give the pure product.
Palmitic acid is naturally produced by a wide range of other plants and organisms, typically at low levels. It is naturally present in butter, cheese, milk, and meat , as well as cocoa butter, soybean oil, and sunflower oil. The cetyl ester of palmitic acid (cetyl palmitate) occurs in spermaceti.