Naphthalene

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Naphthalene
Skeletal formula and numbering system of naphthalene
Ball-and-stick model of naphthalene
Names
Preferred IUPAC name
Naphthalene[1]
Systematic IUPAC name
Bicyclo[4.4.0]deca-1,3,5,7,9-pentaene
Other names
white tar, camphor tar, tar camphor, naphthalin, naphthaline, antimite, albocarbon, hexalene, mothballs, moth flakes
Identifiers
3D model (JSmol)
Beilstein Reference 1421310
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.001.863
EC Number 214-552-7
Gmelin Reference 3347
KEGG
PubChem {{{value}}}
RTECS number QJ0525000
UNII
SMILES {{{value}}}
Properties
C10H8
Molar mass 128.17 g·mol−1
Appearance White solid crystals/ flakes
Odor Strong odor of coal tar
Density 1.145 g/cm3 (15.5 °C)[2]
1.0253 g/cm3 (20 °C)
0.9625 g/cm3 (100 °C)[2]
Melting point 78.2 °C (172.8 °F; 351.3 K)
80.26 °C (176.47 °F; 353.41 K)
at 760 mmHg
Boiling point 217.97 °C (424.35 °F; 491.12 K)
at 760 mmHg[2]
19 mg/L (10 °C)
31.6 mg/L (25 °C)
43.9 mg/L (34.5 °C)
80.9 mg/L (50 °C)>
238.1 mg/L (73.4 °C)[3]
Solubility Soluble in alcohols, liquid ammonia, carboxylic acids, C6H6, SO2,[3] CCl4, CS2, toluene, aniline[4]
Solubility in ethanol 5 g/100 g (0 °C)
11.3 g/100 g (25 °C)
19.5 g/100 g (40 °C)
179 g/100 g (70 °C)[4]
Solubility in acetic acid 6.8 g/100 g (6.75 °C)
13.1 g/100 g (21.5 °C)
31.1 g/100 g (42.5 °C)
111 g/100 g (60 °C)[4]
Solubility in chloroform 19.5 g/100 g (0 °C)
35.5 g/100 g (25 °C)
49.5 g/100 g (40 °C)
87.2 g/100 g (70 °C)[4]
Solubility in hexane 5.5 g/100 g (0 °C)
17.5 g/100 g (25 °C)
30.8 g/100 g (40 °C)
78.8 g/100 g (70 °C)[4]
Solubility in butyric acid 13.6 g/100 g (6.75 °C)
22.1 g/100 g (21.5 °C)
131.6 g/100 g (60 °C)[4]
log P 3.34
Vapor pressure 8.64 Pa (20 °C)
23.6 Pa (30 °C)
0.93 kPa (80 °C)[3]
2.5 kPa (100 °C)[5]
kH 0.42438 L·atm/mol
-91.9·10−6 cm3/mol
Thermal conductivity 98 kPa:
0.1219 W/m·K (372.22 K)
0.1174 W/m·K (400.22 K)
0.1152 W/m·K (418.37 K)
0.1052 W/m·K (479.72 K)[6]
1.5898
Viscosity 0.964 cP (80 °C)
0.761 cP (100 °C)
0.217 cP (150 °C)[7]
Structure
Monoclinic[8]
P21/b[8]
C5
2h
[8]
a = 8.235 Å, b = 6.003 Å, c = 8.658 Å[8]
α = 90°, β = 122.92°, γ = 90°
Thermochemistry
Std enthalpy of
formation
ΔfHo298
78.53 kJ/mol
Std enthalpy of
combustion
ΔcHo298
-5156.3 kJ/mol
Standard molar
entropy
So298
167.39 J/mol·K[5]
Specific heat capacity, C 165.72 J/mol·K
Hazards
Main hazards Flammable, sensitizer, possible carcinogen. Dust can form explosive mixtures with air
NFPA 704

NFPA 704.svg

2
2
0
 
Explosive limits 5.9%
U.S. Permissible
exposure limit (PEL)
TWA 10 ppm (50 mg/m3)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is ☑Y☒N ?)
Infobox references

Naphthalene is a crystalline, white hydrocarbon, with a strong smell. It is best known as the main ingredient in mothballs, urinal deodorizer blocks, and can be used as an antiseptic. In mothballs, it is used as an insecticide or pesticide.

Naphthalene is toxic. In humans, being exposed to naphthalene can destroy red blood cells. Naphthalene may also cause cancer.

History[change | change source]

In the early 1820s, two different papers are published on something that matches the description of Naphthalene. Both groups made it by distilling coal tar. In 1821 John Kidd cited both reports, and condensed their results to accurately describe the properties of naphthalene, and how to make it. Kidd named it naphthalene because "naphtha"  means any explosive hydrocarbon mixture. By 1826, Michael Faraday discovered the formula for it. Emil Erlenmeyer proposes that it is two fused benzene rings in 1866, and Carl Gräbe confirms this three years later.

References[change | change source]

  1. Nomenclature of Organic Chemistry : IUPAC Recommendations and Preferred Names 2013 (Blue Book). Cambridge: The Royal Society of Chemistry. 2014. pp. 13, 35, 204, 207, 221–222, 302, 457, 461, 469, 601, 650. doi:10.1039/9781849733069-FP001. ISBN 978-0-85404-182-4.
  2. 2.0 2.1 2.2 "Ambient Water Quality Criteria for Naphthalene" (PDF). United States Environmental Protection Agency. Retrieved 2014-06-21.
  3. 3.0 3.1 3.2 Anatolievich, Kiper Ruslan. "naphthalene". chemister.ru. Retrieved 2014-06-21.
  4. 4.0 4.1 4.2 4.3 4.4 4.5 Seidell, Atherton; Linke, William F. (1919). Solubility of Inorganic and Organic Compounds (2nd ed.). New York: D. Van Nostrand Company. pp. 443–446.
  5. 5.0 5.1 Naphthalene 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 2014-05-24)
  6. "Thermal Conductivity of Naphthalene". DDBST GmbH. DDBST GmbH. Retrieved 2014-06-21.
  7. "Dynamic Viscosity of Naphthalene". DDBST GmbH. DDBST GmbH. Retrieved 2014-06-21.
  8. 8.0 8.1 8.2 8.3 Douglas, Bodie E.; Ho, Shih-Ming (2007). Structure and Chemistry of Crystalline Solids. New York: Springer Science+Business Media, Inc. p. 288. ISBN 0-387-26147-8.

Other websites[change | change source]