Pyridine

  • Azine
  • Azabenzene
Formula
C5H5N
Structure
Description
Colorless or slightly yellow, liquid, penetrating, disagreeable, fishy odor.
Uses
Deer Repellent, Dog and Cat Repellent

Registry Numbers and Inventories.
CAS
110-86-1
EC (EINECS/ELINCS)
203-809-9
EC Index Number
613-002-00-7
EC Class
Highly flammable; Harmful
R 11 20/21/22
RTECS
UR8400000
RTECS class
Tumorigen; Mutagen; Primary Irritant
UN (DOT)
1282
Merck
12,8153
Beilstein/Gmelin
103233
Beilstein Reference
5-20-05-00160
RCRA
U196
EPA OPP
69202
Swiss Giftliste 1
G-2819
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C5H5N
Formula mass
79.10
Melting point, °C
-44
Boiling point, °C
115
Vapor pressure, mmHg
16 (20 C)
Vapor density (air=1)
2.73
Saturation Concentration
65 g/m3 (20 C)
Evaporization number
12.7 (diethyl ether = 1)
Odor Threshold Odor threshold 21 ppb
Critical temperature
346.8
Critical pressure
55.8
Density
0.983 g/cm3 (20 C)
Solubility in water
Miscible
Viscosity
0.97 cP (20 C)
Surface tension
38.0 g/s2 (20 C)
Refractive index
1.5092 (20 C)
Dipole moment
2.2 D (20 C)
Dielectric constant
12.3 (25 C)
pKa/pKb
8.81 (pKb)
Partition coefficient, pKow
0.62 to 0.78
Heat of vaporization
40.2 kJ/mol
Heat of combustion
-2618 kJ/mol

Hazards and Protection.
Storage
Keep away from heat, sparks, and flame. Keep away from sources of ignition. Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances. Flammables-area.
B2
Handling
Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Use only in a well ventilated area. Ground and bond containers when transferring material. Do not get in eyes, on skin, or on clothing. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Keep container tightly closed. Avoid contact with heat, sparks and flame. Do not ingest or inhale. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks
Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container. Avoid runoff into storm sewers and ditches which lead to waterways. Clean up spills immediately, using the appropriate protective equipment. Remove all sources of ignition. Use a spark-proof tool. Provide ventilation. A vapor suppressing foam may be used to reduce vapors.
Stability
Stable under normal temperatures and pressures. When heated to decompostion cyanide fumes are released.
Incompatibilities
Acids; acid chlorides; oxidizing agents; chloroformates; bromine trifluoride; mixtures with formamide, iodine, and sulfur trioxide, chlorosulfonic acid, chromic acid, maleic anhydride, sulfuric acid, perchromates, and dinitrogen tetroxide
Decomposition
Nitrogen oxides, carbon monoxide, carbon dioxide, nitrogen.

Fire.
Flash Point,°C
17
Autoignition, °C
550
Upper exp. limit, %
12.4
Lower exp. limit, %
1.7
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Water may be ineffective. Material is lighter than water and a fire may be spread by the use of water. Containers may explode in the heat of a fire. Extinguishing media: For small fires, use dry chemical, carbon dioxide, water spray or alcohol-resistant foam. For large fires, use water spray, fog, or alcohol-resistant foam. Do NOT use straight streams of water. Cool containers with flooding quantities of water until well after fire is out.
Fire potential
Flammable liquid and vapor.
Hazards
Vapor is heavier than air and may travel considerable distance to source of ignition and flash back.
Combustion products
Toxic gases and vapors (such as oxides of nitrogen and carbon monoxide) may be released in a fire involving pyridine.
Health
3
 
Flammability
3
 
 
Reactivity
0
 

Health.
Exposure limit(s)
TLV (as TWA): 5 ppm; 16 mg/m3 (ACGIH 199?-199?). MAK: 5 ppm; 15 mg/m3; (1992). OSHA PEL: TWA 5 ppm (15 mg/m3) NIOSH REL: TWA 5 ppm (15 mg/m3) NIOSH IDLH: 1000 ppm
Carcinogin
G-A3, CP65
Poison_Class
4
Exposure effects
Prolonged or repeated skin contact may cause dermatitis. Chronic inhalation and ingestion may cause effects similar to those of acute inhalation and ingestion. May cause liver and kidney damage. Exposures to doses of pyridine that are too low to produce overt clinical symptoms can cause liver damage and repeated low-level exposures can cause cirrhosis. Feeding studies in rats produced blood effects like changes in clotting factors.
   Ingestion
May cause gastrointestinal irritation with nausea, vomiting and diarrhea. May cause liver and kidney damage. May cause central nervous system depression, characterized by excitement, followed by headache, dizziness, drowsiness, and nausea. Advanced stages may cause collapse, unconsciousness, coma and possible death due to respiratory failure. May cause effects similar to those for inhalation exposure. Effects may be delayed.
   Inhalation
Inhalation of high concentrations may cause central nervous system effects characterized by headache, dizziness, unconsciousness and coma. May cause respiratory tract irritation. Prolonged exposure may result in dizziness and general weakness.
   Skin
May cause skin irritation. May be harmful if absorbed through the skin. Effects may be delayed. May cause smarting of the skin and first-degree burns on short exposure.
   Eyes
Contact with eyes may cause severe irritation, and possible eye burns.

First aid
 
   Ingestion
Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
   Inhalation
Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid. DO NOT use mouth-to-mouth respiration.
   Skin
Get medical aid immediately. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse.
   Eyes
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.

Transport.
UN number
1282
Response guide
Hazard class
3
Packing Group
II
 
USCG CHRIS Code
PRD
 
9 Aromatic amines
HS Code
2933 31 00
 
Std. Transport #
4909277
 
IMO Chemical Code
17
IMO Pollution Category
D
IMO Hazard code
S