Pyridine
Properties, data and information sources.
Contents
Pyridine is a basic, aromatic, heterocyclic, organic chemical compound that is structurally related to benzene, with one methine group (=CH-) replaced by a nitrogen atom.
Names and Identifiers
Formula
C5H5N
Molar mass
79.102 (g/mol)
CAS registry number
110-86-1
EC number EINECS
203-809-9
InChI Key
JUJWROOIHBZHMG-UHFFFAOYSA-N
Other names, synonyms
Azabenzene; Azine; Azinine
Latin name
Pyridinium
Chemical formulas
Molecular formula and structural formula of Pyridine:
C5H5N
Mr = 79.102 g/mol
SMILES: C1=CC=NC=C1
Data and Properties
In its pure form, pyridine is a colorless, often light yellow, hygroscopic liquid that has an unpleasant fishy, nauseating odor and is corrosive to plastics, plastic coatings and rubber.
solubility:+ Miscible with
water, alcohol,
acetone, ether,
benzene,
chloroform, fatty oils and many organic solvents.
partition coefficient logPOW = 0.65.
melting point
-41.6 °C
boiling point
115.2 °C
flash point
21 °C
ignition temperature
482 °C
density
0.98272 g cm-3 at 20 °C
pKa value
pK1a = 5.23 at 25 °C
vapor pressure
20.5 hPa at 20 °C
viscosity
0.974 cP at 20 °C
0.879 cP at 25 °C
surface tension
40.8 dyn/cm at 0 °C
38.0 dyn/cm at 20 °C
26.4 dyn/cm at 100 °C
refractive index
nD = 1.50920 at 20 °C
standard enthalpy of formation
100.2 kJ/mol at 25 °C [l]
140 kJ/mol [g]
standard entropie
177 J/(mol K) at 25 °C
enthalpy of vaporization
40.2 kJ/mol
melting enthalpy
8.28 kJ/mol
enthalpy of combustion
-2.782 MJ/mol
entropie of combustion
35.8 J/(mol K)
heat capacity
132.72 J/(mol K)
thermal conductivity
0.166 W/(m · K)
critical points
Tc = 346.85 °C
pc = 67 bar
Vc = 229 cm3/mol
triple point
-41.67 °C
dipole moment
2.215 D
ionization energy
9.27 eV
permittivity
ε0 = 12.3 at 25 °C
(dielectric constant)
magnetism
diamagnetisch
magnetic susceptibility χ
-48.7 × 10-6 cm3 mol-1
crystal structure:
Orthorhombic crystal system, space group Pna21 No. 33, lattice parameters a = 1752 pm, b = 897 pm and c = 1135 pm, Z = 16.
Spectroscopic data:
SPLASH (mass spectra)
splash10-0ufr-9000000000-445aeb46f419295729de
splash10-0fb9-9000000000-f99a956b2e7b0837d371
splash10-001i-9000000000-2e20e7f7bd046f0fcbbf
splash10-001i-9000000000-d87b34d2e067451d9968
MoNA Mass Bank of North America (mass spectrum)JUJWROOIHBZHMG-UHFFFAOYSA-N SpectraBase (NMR, IR, FTIR, Raman, UV-Vis, MS ... spectra)8dRCAjhTReY Human Metabolome Database (GC-MS, LC-MS/MS spectra, NMR)HMDB0000926 Calculated NMR spectrum (Predict Spectra via NMRDB)
1H NMR Spektrum, 13C NMR Spektrum.
Percentage and isotopic composition:
Mass-related elemental composition and isotope proportions of the compound Pyridine - C5H5N - calculated based on molecular mass.
Symbol
Element ENumber x
of atoms ExData of the element
and isotopes *Percentages
of isotopesPercentage of
Ex in formula massC
Carbon5 Ar = 12.011 u
ΣAr = 60.055 u
12C: 12 u [98,94 %]
14C: 14.00324 u [<< 1 %]
13C: 13.00335 u [1,06 %]
12C: 75.1162 %
14C: trace
13C: 0.80476 %
75.9210 %H
Hydrogen5 Ar = 1.008 u
ΣAr = 5.04 u
3H: 3.01605 u [<< 1 %]
1H: 1.00783 u [99,99 %]
2H: 2.0141 u [0,01 %]
3H: trace
1H: 6.37088 %
2H: 0.00064 %
6.3715 %N
Nitrogen1ΣAr = 14.007 u
14N: 14.00307 u [99,6205 %]
15N: 15.00011 u [0,3795 %]
14N: 17.64032 %
15N: 0.0672 %
17.7075 % *) The third column lists the atomic masses or isotope masses of the elements involved and - in square brackets - the natural isotope composition.
More calculated data
The molar mass is M = 79.102 grams per mole.
The amount of substance in one kilogram of the substance is n = 12.642 mol.
The amount of substance in one gram of the substance is n = 0.013 mol.
Monoisotopic mass: 79.042199165251 Da - related to 12C51H514N.
Hazard warnings according to GHS
(General information without guarantee of accuracy and completeness! The information does not replace the chemical safety data sheet or a risk assessment, but rather provides a general overview of the risk posed by the hazardous substance.
Signal word: Danger
GHS hazard statements (H phrases):
H225
Highly flammable liquid and vapour
H302
Harmful if swallowed
H312
Harmful in contact with skin
H315
Causes skin irritation
H319
Causes serious eye irritation
H332
Harmful if inhaled
In a range of 1.7 to 12,4 vol%, pyridine forms explosive mixtures with air.
LD50 (rat, oral): 892 mg/kg.
Labeling in the EU: See ECHA Substance Infocard 100.003.464.
WHO IARC group 2B: Possibly carcinogenic to humans! See there under monograph 77, 119, (2019).
For toxicology and occupational safety when handling Pyridine as well as measures to be taken in case of danger, see: Hazardous Substances Information System GESTIS, ZVG-Nr. 013850.
International Chemical Safety Card ICSC (SDS, MSDS): See ICSC: 0323.
External Sources
PubChem:ID 1049ChemSpider:ID 1020Kegg database DBGET:ID C00747UNII of the FDA (USA):Unique Ingredient Identifier NH9L3PP67SEPA CompTox Chemicals Dashboard:DTXSID9021924Other CAS RN:152758-95-7; 163392-20-9; 45410-39-7; 62301-32-0; 6999-00-4; 82005-06-9; 85404-19-9; 85404-20-2; 733733-47-6; 857961-06-9 (also used, outdated or deleted registration numbers)
Manufacturers and Sources of Supply
Pyridine as a commercial product from internationally active suppliers and search for analogues see: ZINC000000895354.
The table below lists producers and suppliers of Pyridine as a commercial chemical for laboratories, research, industry and production with the corresponding contact details.
Literature Sources
[0] - Specialist and research articles in scientific journals via PubMed: Pyridine.
Last update: 2024-09-03
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