Stearic acid

^[1]
Names
	Preferred IUPAC name Octadecanoic acid
	Other names Stearic acid; C18:0 (Lipid numbers)
Identifiers
CAS Number	57-11-4 ;
3D model (JSmol)	Interactive image;
ChEMBL	ChEMBL46403 ;
ChemSpider	5091 ;
DrugBank	DB03193 ;
ECHA InfoCard	100.000.285
EC Number	200-313-4;
IUPHAR/BPS	3377;
PubChem CID	5281;
RTECS number	WI2800000;
UNII	4ELV7Z65AP ;
CompTox Dashboard (EPA)	DTXSID8021642 ;
	show SMILES
Properties
Chemical formula	C18H36O2
Molar mass	284.484 g·mol−1
Appearance	White solid
Odor	Pungent, oily
Density	0.9408 g/cm3 (20 °C); 0.847 g/cm3 (70 °C)
Melting point	69.3 °C (156.7 °F; 342.4 K)
Boiling point	361 °C (682 °F; 634 K) ; decomposes; 232 °C (450 °F; 505 K); at 15 mmHg
Solubility in water	0.00018 g/100 g (0 °C); 0.00029 g/100 g (20 °C); 0.00034 g/100 g (30 °C); 0.00042 g/100 g (45 °C); 0.00050 g/100 g (60 °C)
Solubility	Soluble in alkyl acetates, alcohols, HCOOCH3, phenyls, CS2, CCl4
Solubility in dichloromethane	3.58 g/100 g (25 °C); 8.85 g/100 g (30 °C); 18.3 g/100 g (35 °C)
Solubility in hexane	0.5 g/100 g (20 °C); 4.3 g/100 g (30 °C); 19 g/100 g (40 °C); 79.2 g/100 g (50 °C); 303 g/100 g (60 °C)
Solubility in ethanol	1.09 g/100 mL (10 °C); 2.25 g/100 g (20 °C); 5.42 g/100 g (30 °C); 22.7 g/100 g (40 °C) ; 105 g/100 g (50 °C); 400 g/100 g (60 °C)
Solubility in acetone	4.73 g/100 g
Solubility in chloroform	15.54 g/100 g
Solubility in toluene	13.61 g/100 g
Vapor pressure	0.01 kPa (158 °C); 0.46 kPa (200 °C); 16.9 kPa (300 °C)
Magnetic susceptibility (χ)	−220.8·10−6 cm3/mol
Thermal conductivity	0.173 W/m·K (70 °C) ; 0.166 W/m·K (100 °C)
Refractive index (nD)	1.4299 (80 °C)
Structure
Crystal structure	B-form = Monoclinic
Space group	B-form = P21/a
Point group	B-form = Cs; 2h
Lattice constant	a = 5.591 Å, b = 7.404 Å, c = 49.38 Å (B-form) α = 90°, β = 117.37°, γ = 90°
Thermochemistry
Heat capacity (C)	501.5 J/mol·K
Std molar; entropy (So298)	435.6 J/mol·K
Std enthalpy of; formation (ΔfH⦵298)	−947.7 kJ/mol
Std enthalpy of; combustion (ΔcH⦵298)	11342.4 kJ/mol
Hazards
NFPA 704 (fire diamond)	1 1 0
Flash point	113 °C (235 °F; 386 K)
	Lethal dose or concentration (LD, LC):
LD50 (median dose)	4640 mg/kg (rats, oral); 21.5 mg/kg (rats, intravenous)
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
	Infobox references

Stearic acid (/ˈstɪərɪk/ STEER-ik, /stiˈærɪk/ stee-ARR-ik) is a saturated fatty acid with an 18-carbon chain. The IUPAC name is octadecanoic acid. It is a waxy solid and its chemical formula is C₁₇H₃₅CO₂H. Its name comes from the Greek word στέαρ "stéar", which means tallow. The salts and esters of stearic acid are called stearates. As its ester, stearic acid is one of the most common saturated fatty acids found in nature following palmitic acid.^[11] The triglyceride derived from three molecules of stearic acid is called stearin.

Production[]

Stearic acid is obtained from fats and oils by the saponification of the triglycerides using hot water (about 100 °C). The resulting mixture is then distilled.^[12] Commercial stearic acid is often a mixture of stearic and palmitic acids, although purified stearic acid is available.^{[citation needed]}

Stearic acid is more abundant in animal fat (up to 30%) than in vegetable fat (typically <5%). The important exceptions are the foods cocoa butter (34%)^[13] and shea butter, where the stearic acid content (as a triglyceride) is 28–45%.^[14] Commercially, fats high in oleic acid such as palm and soy may be hydrogenated to convert oleic into stearic acid.^[15]^[16]

In terms of its biosynthesis, stearic acid is produced from carbohydrates via the fatty acid synthesis machinery wherein acetyl-CoA contributes two-carbon building blocks.^{[citation needed]}

Uses[]

In general, the applications of stearic acid exploit its bifunctional character, with a polar head group that can be attached to metal cations and a nonpolar chain that confers solubility in organic solvents. The combination leads to uses as a surfactant and softening agent. Stearic acid undergoes the typical reactions of saturated carboxylic acids, a notable one being reduction to stearyl alcohol, and esterification with a range of alcohols. This is used in a large range of manufactures, from simple to complex electronic devices.^{[citation needed]}

As food additive[]

Stearic acid (E number E570) is found in some foods.^[17]

Soaps, cosmetics, detergents[]

Stearic acid is mainly used in the production of detergents, soaps, and cosmetics such as shampoos and shaving cream products. Soaps are not made directly from stearic acid, but indirectly by saponification of triglycerides consisting of stearic acid esters. Esters of stearic acid with ethylene glycol, glycol stearate, and glycol distearate are used to produce a pearly effect in shampoos, soaps, and other cosmetic products. They are added to the product in molten form and allowed to crystallize under controlled conditions. Detergents are obtained from amides and quaternary alkylammonium derivatives of stearic acid.^{[citation needed]}

Lubricants, softening and release agents[]

In view of the soft texture of the sodium salt, which is the main component of soap, other salts are also useful for their lubricating properties. Lithium stearate is an important component of grease. The stearate salts of zinc, calcium, cadmium, and lead are used to soften PVC. Stearic acid is used along with castor oil for preparing softeners in textile sizing. They are heated and mixed with caustic potash or caustic soda. Related salts are also commonly used as release agents, e.g. in the production of automobile tires. As an example, it can be used to make castings from a plaster piece mold or waste mold, and to make a mold from a shellacked clay original. In this use, powdered stearic acid is mixed in water and the suspension is brushed onto the surface to be parted after casting. This reacts with the calcium in the plaster to form a thin layer of calcium stearate, which functions as a release agent.^[18]

When reacted with zinc it forms zinc stearate, which is used as a lubricant for playing cards (fanning powder) to ensure a smooth motion when fanning. Stearic acid is a common lubricant during injection molding and pressing of ceramic powders.^[19] It is also used as a mold release for foam latex that is baked in stone molds.^{[citation needed]}

Niche uses[]

Being inexpensive, nontoxic, and fairly inert, stearic acid finds many niche applications.^[12] Stearic acid is used as a negative plate additive in the manufacture of lead-acid batteries. It is added at the rate of 0.6 g per kg of the oxide while preparing the paste. It is believed to enhance the hydrophobicity of the negative plate, particularly during dry-charging process. It also reduces the extension of oxidation of the freshly formed lead (negative active material) when the plates are kept for drying in the open atmosphere after the process of tank formation. As a consequence, the charging time of a dry uncharged battery during initial filling and charging (IFC) is comparatively lower, as compared to a battery assembled with plates which do not contain stearic acid additive. Fatty acids are classic components of candle-making. Stearic acid is used along with simple sugar or corn syrup as a hardener in candies. In fireworks, stearic acid is often used to coat metal powders such as aluminium and iron. This prevents oxidation, allowing compositions to be stored for a longer period of time.^{[citation needed]}

Metabolism[]

An isotope labeling study in humans^[20] concluded that the fraction of dietary stearic acid that oxidatively desaturates to oleic acid is 2.4 times higher than the fraction of palmitic acid analogously converted to palmitoleic acid. Also, stearic acid is less likely to be incorporated into cholesterol esters. In epidemiologic and clinical studies, stearic acid was found to be associated with lowered LDL cholesterol in comparison with other saturated fatty acids.^[21]

Salts and esters[]

Stearates are the salts or esters of stearic acid. The conjugate base of stearic acid, C₁₇H₃₅COO⁻, is also known as the stearate anion.

Examples[]

Salts

Esters

References[]

^ Susan Budavari, ed. (1989). Merck Index (11th ed.). Rahway, New Jersey: Merck & Co., Inc. p. 8761. ISBN 978-0-911910-28-5.
^ Jump up to: ^a ^b ^c ^d ^e ^f ^g ^h Lide, David R., ed. (2009). CRC Handbook of Chemistry and Physics (90th ed.). Boca Raton, Florida: CRC Press. ISBN 978-1-4200-9084-0.
^ Jump up to: ^a ^b Ralston, A.W.; Hoerr, C.W. (1942). "The Solubilities of the Normal Saturated Fatty Acids". The Journal of Organic Chemistry. 7 (6): 546–555. doi:10.1021/jo01200a013. PMID 20280727.
^ Jump up to: ^a ^b ^c ^d "stearic acid". Chemister.ru. 2007-03-19. Retrieved 2017-06-30.
^ Jump up to: ^a ^b ^c Seidell, Atherton; Linke, William F. (1919). Solubilities of Inorganic and Organic Compounds (2nd ed.). D. Van Nostrand Company. p. 677.
^ Jump up to: ^a ^b Octadecanoic acid in Linstrom, Peter J.; Mallard, William G. (eds.); NIST Chemistry WebBook, NIST Standard Reference Database Number 69, National Institute of Standards and Technology, Gaithersburg (MD), http://webbook.nist.gov (retrieved 2014-06-15)
^ Vargaftik, Natan B.; et al. (1993). Handbook of Thermal Conductivity of Liquids and Gases (illustrated ed.). CRC Press. p. 318. ISBN 978-0-8493-9345-7.
^ Jump up to: ^a ^b ^c ^d von Sydow, E. (1955). "On the structure of the crystal form B of stearic acid". Acta Crystallographica. 8 (9): 557–560. doi:10.1107/S0365110X55001746.
^ National Center for Biotechnology Information (2021). PubChem Compound Summary for CID 5281, Stearic acid. Retrieved January 7, 2021 from https://pubchem.ncbi.nlm.nih.gov/compound/Stearic-acid.
^ Science Lab.com. "Stearic acid MSDS" (PDF). Retrieved 2020-09-30.
^ Gunstone, F. D., John L. Harwood, and Albert J. Dijkstra "The Lipid Handbook with Cd-Rom. 3rd ed. Boca Raton: CRC Press, 2007. ISBN 0849396883 | ISBN 978-0849396885
^ Jump up to: ^a ^b Anneken, David J.; Both, Sabine; Christoph, Ralf; Fieg, Georg; Steinberner, Udo; Westfechtel, Alfred (2006). "Fatty Acids". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a10_245.pub2.
^ "硬脂酸;十八烷酸;十八酸;十八碳烷酸;Stearic acid;Octadecanoic acid;物理性质,化学性质,英文名,分子量,结构式,分子式,CAS号,制备方法,用途,溶点,沸点,毒性,MSDS,供应商,公司". www.chemyq.com. Retrieved 2020-06-17.
^ Beare-Rogers, J.; Dieffenbacher, A.; Holm, J.V. (2001). "Lexicon of lipid nutrition (IUPAC Technical Report)". Pure and Applied Chemistry. 73 (4): 685–744. doi:10.1351/pac200173040685. S2CID 84492006.
^ https://www.profitableventure.com/how-much-stearic-acid-soap-making/
^ https://cailapares.com/en/hydrogenated-stearic-acids-vegetable-origin/
^ Fernando Aguilar, Riccardo Crebelli, Alessandro Di Domenico, Birgit Dusemund, Maria Jose Frutos, Pierre Galtier, David Gott, Ursula Gundert-Remy, Claude Lambré, Jean-Charles Leblanc, Oliver Lindtner, Peter Moldeus, Alicja Mortensen, Pasquale Mosesso, Dominique Parent-Massin, Agneta Oskarsson, Ivan Stankovic, Ine Waalkens-Berendsen, Rudolf Antonius Woutersen, Matthew Wright and Maged Younes. (2017). "Re-evaluation of fatty acids (E 570) as a food additive". EFSA Journal. 15 (5): 4785. doi:10.2903/j.efsa.2017.4785. PMC 7009963. PMID 32625490.CS1 maint: multiple names: authors list (link)
^ Angelo Nora, Alfred Szczepanek, Gunther Koenen (2005). "Metallic Soaps". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a16_361.CS1 maint: multiple names: authors list (link)
^ Tsenga, Wenjea J.; Mo Liua, Dean; Hsub, Chung-King (1999). "Influence of stearic acid on suspension structure and green microstructure of injection-molded zirconia ceramics". Ceramics International. 25 (2): 191–195. doi:10.1016/S0272-8842(98)00024-8.
^ Emken, Edward A. (1994). "Metabolism of dietary stearic acid relative to other fatty acids in human subjects". American Journal of Clinical Nutrition. 60 (6): 1023S–1028S. doi:10.1093/ajcn/60.6.1023S. PMID 7977144.
^ Hunter, J. E.; Zhang, J.; Kris-Etherton, P. M. (2009). "Cardiovascular disease risk of dietary stearic acid compared with trans, other saturated, and unsaturated fatty acids: A systematic review". American Journal of Clinical Nutrition. 91 (1): 46–63. doi:10.3945/ajcn.2009.27661. PMID 19939984.

External links[]

NIST Chemistry WebBook Entry

[1] Susan Budavari, ed. (1989). Merck Index (11th ed.). Rahway, New Jersey: Merck & Co., Inc. p. 8761. ISBN 978-0-911910-28-5.

[crc-2] Jump up to: ^a ^b ^c ^d ^e ^f ^g ^h Lide, David R., ed. (2009). CRC Handbook of Chemistry and Physics (90th ed.). Boca Raton, Florida: CRC Press. ISBN 978-1-4200-9084-0.

[Ralston-3] Jump up to: ^a ^b Ralston, A.W.; Hoerr, C.W. (1942). "The Solubilities of the Normal Saturated Fatty Acids". The Journal of Organic Chemistry. 7 (6): 546–555. doi:10.1021/jo01200a013. PMID 20280727.

[chemister-4] Jump up to: ^a ^b ^c ^d "stearic acid". Chemister.ru. 2007-03-19. Retrieved 2017-06-30.

[sioc-5] Jump up to: ^a ^b ^c Seidell, Atherton; Linke, William F. (1919). Solubilities of Inorganic and Organic Compounds (2nd ed.). D. Van Nostrand Company. p. 677.

[nist-6] Jump up to: ^a ^b Octadecanoic acid in Linstrom, Peter J.; Mallard, William G. (eds.); NIST Chemistry WebBook, NIST Standard Reference Database Number 69, National Institute of Standards and Technology, Gaithersburg (MD), http://webbook.nist.gov (retrieved 2014-06-15)

[7] Vargaftik, Natan B.; et al. (1993). Handbook of Thermal Conductivity of Liquids and Gases (illustrated ed.). CRC Press. p. 318. ISBN 978-0-8493-9345-7.

[csba-8] Jump up to: ^a ^b ^c ^d von Sydow, E. (1955). "On the structure of the crystal form B of stearic acid". Acta Crystallographica. 8 (9): 557–560. doi:10.1107/S0365110X55001746.

[9] National Center for Biotechnology Information (2021). PubChem Compound Summary for CID 5281, Stearic acid. Retrieved January 7, 2021 from https://pubchem.ncbi.nlm.nih.gov/compound/Stearic-acid.

[10] Science Lab.com. "Stearic acid MSDS" (PDF). Retrieved 2020-09-30.

[lipidhb-11] Gunstone, F. D., John L. Harwood, and Albert J. Dijkstra "The Lipid Handbook with Cd-Rom. 3rd ed. Boca Raton: CRC Press, 2007. ISBN 0849396883 | ISBN 978-0849396885

[Ullmann-12] Jump up to: ^a ^b Anneken, David J.; Both, Sabine; Christoph, Ralf; Fieg, Georg; Steinberner, Udo; Westfechtel, Alfred (2006). "Fatty Acids". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a10_245.pub2.

[13] "硬脂酸;十八烷酸;十八酸;十八碳烷酸;Stearic acid;Octadecanoic acid;物理性质,化学性质,英文名,分子量,结构式,分子式,CAS号,制备方法,用途,溶点,沸点,毒性,MSDS,供应商,公司". www.chemyq.com. Retrieved 2020-06-17.

[lexicon-14] Beare-Rogers, J.; Dieffenbacher, A.; Holm, J.V. (2001). "Lexicon of lipid nutrition (IUPAC Technical Report)". Pure and Applied Chemistry. 73 (4): 685–744. doi:10.1351/pac200173040685. S2CID 84492006.

[15] ttps://www.profitableventure.com/how-much-stearic-acid-soap-making/

[16] ttps://cailapares.com/en/hydrogenated-stearic-acids-vegetable-origin/

[17] Fernando Aguilar, Riccardo Crebelli, Alessandro Di Domenico, Birgit Dusemund, Maria Jose Frutos, Pierre Galtier, David Gott, Ursula Gundert-Remy, Claude Lambré, Jean-Charles Leblanc, Oliver Lindtner, Peter Moldeus, Alicja Mortensen, Pasquale Mosesso, Dominique Parent-Massin, Agneta Oskarsson, Ivan Stankovic, Ine Waalkens-Berendsen, Rudolf Antonius Woutersen, Matthew Wright and Maged Younes. (2017). "Re-evaluation of fatty acids (E 570) as a food additive". EFSA Journal. 15 (5): 4785. doi:10.2903/j.efsa.2017.4785. PMC 7009963. PMID 32625490.CS1 maint: multiple names: authors list (link)

[Ull2-18] Angelo Nora, Alfred Szczepanek, Gunther Koenen (2005). "Metallic Soaps". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a16_361.CS1 maint: multiple names: authors list (link)

[19] Tsenga, Wenjea J.; Mo Liua, Dean; Hsub, Chung-King (1999). "Influence of stearic acid on suspension structure and green microstructure of injection-molded zirconia ceramics". Ceramics International. 25 (2): 191–195. doi:10.1016/S0272-8842(98)00024-8.

[20] Emken, Edward A. (1994). "Metabolism of dietary stearic acid relative to other fatty acids in human subjects". American Journal of Clinical Nutrition. 60 (6): 1023S–1028S. doi:10.1093/ajcn/60.6.1023S. PMID 7977144.

[21] Hunter, J. E.; Zhang, J.; Kris-Etherton, P. M. (2009). "Cardiovascular disease risk of dietary stearic acid compared with trans, other saturated, and unsaturated fatty acids: A systematic review". American Journal of Clinical Nutrition. 91 (1): 46–63. doi:10.3945/ajcn.2009.27661. PMID 19939984.

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show v t Lipids: fatty acids
Saturated	Propionic (C3) Butyric (C4) Valeric (C5) Caproic (C6) Enanthic (C7) Caprylic (C8) Pelargonic (C9) Capric (C10) Undecylic (C11) Lauric (C12) Tridecylic (C13) Myristic (C14) Pentadecylic (C15) Palmitic (C16) Margaric (C17) Stearic (C18) Nonadecylic (C19) Arachidic (C20) Heneicosylic (C21) Behenic (C22) Tricosylic (C23) Lignoceric (C24) Pentacosylic (C25) Cerotic (C26) Heptacosylic (C27) Montanic (C28) Nonacosylic (C29) Melissic (C30) Hentriacontylic (C31) Lacceroic (C32) Psyllic (C33) Geddic (C34) Ceroplastic (C35) Hexatriacontylic (C36) Heptatriacontanoic (C37) (C38) (C39) (C40)
ω−3 Unsaturated	(8:1) (10:1) (10:2) (12:1) (12:2) (14:1) (14:2) (14:3) (16:3) (16:4) α-Linolenic (18:3) Stearidonic (18:4) (20:3) Eicosatetraenoic (20:4) Eicosapentaenoic (20:5) Clupanodonic (22:5) Docosahexaenoic (22:6) (24:5) (24:6)
	Myristoleic (14:1) (16:1) α-Eleostearic (18:3) β-Eleostearic (trans-18:3) Punicic (18:3) (18:3) (20:3) (20:4)
ω−6 Unsaturated	(14:1) (18:1) Linoleic (18:2) Linolelaidic (trans-18:2) γ-Linolenic (18:3) Calendic (18:3) Pinolenic (18:3) (20:2) Dihomo-γ-linolenic (20:3) Arachidonic (20:4) Adrenic (22:4) Osbond (22:5)
ω−7 Unsaturated	Palmitoleic (16:1) Vaccenic (18:1) Rumenic (18:2) Paullinic (20:1) (20:3)
ω−9 Unsaturated	Oleic (18:1) Elaidic (trans-18:1) Gondoic (20:1) Erucic (22:1) Nervonic (24:1) (20:2) Mead (20:3)
	Sapienic (16:1)
	Gadoleic (20:1)
	(16:1) Petroselinic (18:1) (20:1)

show v t Types of lipids
General	Saturation: Saturated fat Unsaturated fat Monounsaturated fat Polyunsaturated fat Essential fatty acid Other: Fat Oil
Geometry	Trans fat Omega-3 fatty acid Omega-6 fatty acid Omega-9 fatty acid
Eicosanoids	Arachidonic acid Prostaglandins Prostacyclin Thromboxane Leukotrienes
Fatty acids	Caprylic acid Capric acid Lauric acid Myristic acid Palmitic acid Stearic acid Arachidic acid Behenic acid Lignoceric acid
Glycerides	Monoglyceride Diglyceride Triglyceride Triheptanoin Trimyristin Tripalmitin Tristearin Trilinolein Triolein
Phospholipids	Phosphatidylserine Phosphatidylinositol Phosphatidyl ethanolamine Cardiolipin Dipalmitoylphosphatidylcholine
Sphingolipids	Ceramide
Steroids	Cholesterol Corticosteroids Sex steroids Secosteroids

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Names



Preferred IUPAC name Octadecanoic acid
Other names Stearic acid C18:0 (Lipid numbers)
Identifiers
CAS Number	57-11-4^Y
3D model (JSmol)	Interactive image
ChEMBL	ChEMBL46403^Y
ChemSpider	5091^Y
DrugBank	DB03193^Y
ECHA InfoCard	100.000.285
EC Number	200-313-4
IUPHAR/BPS	3377
PubChem CID	5281
RTECS number	WI2800000
UNII	4ELV7Z65AP^Y
CompTox Dashboard (EPA)	DTXSID8021642
show SMILES CCCCCCCCCCCCCCCCCC(=O)O
Properties
Chemical formula	C₁₈H₃₆O₂
Molar mass	284.484 g·mol⁻¹
Appearance	White solid
Odor	Pungent, oily
Density	0.9408 g/cm³ (20 °C)^[2] 0.847 g/cm³ (70 °C)
Melting point	69.3 °C (156.7 °F; 342.4 K) ^[2]
Boiling point	361 °C (682 °F; 634 K) decomposes 232 °C (450 °F; 505 K) at 15 mmHg^[2]
Solubility in water	0.00018 g/100 g (0 °C) 0.00029 g/100 g (20 °C) 0.00034 g/100 g (30 °C) 0.00042 g/100 g (45 °C) 0.00050 g/100 g (60 °C)^[3]
Solubility	Soluble in alkyl acetates, alcohols, HCOOCH₃, phenyls, CS₂, CCl₄^[4]
Solubility in dichloromethane	3.58 g/100 g (25 °C) 8.85 g/100 g (30 °C) 18.3 g/100 g (35 °C)^[4]
Solubility in hexane	0.5 g/100 g (20 °C) 4.3 g/100 g (30 °C) 19 g/100 g (40 °C) 79.2 g/100 g (50 °C) 303 g/100 g (60 °C)^[4]
Solubility in ethanol	1.09 g/100 mL (10 °C) 2.25 g/100 g (20 °C) 5.42 g/100 g (30 °C) 22.7 g/100 g (40 °C) 105 g/100 g (50 °C) 400 g/100 g (60 °C)^[3]
Solubility in acetone	4.73 g/100 g^[5]
Solubility in chloroform	15.54 g/100 g^[5]
Solubility in toluene	13.61 g/100 g^[5]
Vapor pressure	0.01 kPa (158 °C)^[2] 0.46 kPa (200 °C) 16.9 kPa (300 °C)^[6]
Magnetic susceptibility (χ)	−220.8·10⁻⁶ cm³/mol
Thermal conductivity	0.173 W/m·K (70 °C) 0.166 W/m·K (100 °C)^[7]
Refractive index (n_D)	1.4299 (80 °C)^[2]
Structure
Crystal structure	B-form = Monoclinic^[8]
Space group	B-form = P2₁/a^[8]
Point group	B-form = C^s _2h^[8]
Lattice constant	a = 5.591 Å, b = 7.404 Å, c = 49.38 Å (B-form)^[8] α = 90°, β = 117.37°, γ = 90°
Thermochemistry
Heat capacity (C)	501.5 J/mol·K^[2]^[6]
Std molar entropy (S^o₂₉₈)	435.6 J/mol·K^[2]
Std enthalpy of formation (Δ_fH^⦵₂₉₈)	−947.7 kJ/mol^[2]
Std enthalpy of combustion (Δ_cH^⦵₂₉₈)	11342.4 kJ/mol^[9]
Hazards
NFPA 704 (fire diamond)	1 1 0
Flash point	113 °C (235 °F; 386 K)
Lethal dose or concentration (LD, LC):
LD₅₀ (median dose)	4640 mg/kg (rats, oral)^[10] 21.5 mg/kg (rats, intravenous)^[4]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references