Cyclopentene

Formula
C5H8
Structure
Description
A clear, colorless liquid.
Uses
Used to make rubber and plastics.

Registry Numbers and Inventories.
CAS
142-29-0
EC (EINECS/ELINCS)
205-532-9
R 11 21/22 36/37/38 65
S 9 16 26 33 36 62
RTECS
GY5950000
RTECS class
Other
UN (DOT)
2246
Beilstein/Gmelin
635707
Beilstein Reference
4-05-00-00209
Swiss Giftliste 1
G-4395
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C5H8
Formula mass
68.13
Melting point, °C
-135.0
Boiling point, °C
44
Vapor pressure, mmHg
278 (25 C)
Vapor density (air=1)
2.3
Critical temperature
268
Critical pressure
48
Density
0.772 g/cm3 (20 C)
Solubility in water
Slightly soluble
Viscosity
0.365 cp (15 C)
Surface tension
22.65 g/s2 (20 C)
Refractive index
1.4222 (20 C)
Partition coefficient, pKow
1.77
Heat of vaporization
27.6 kJ/mol
Heat of combustion
-3116 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. Refrigerator/flammables.
Handling
Wash thoroughly after handling. Use only in a well ventilated area. Ground and bond containers when transferring material. Avoid contact with eyes, skin, and 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. Avoid ingestion and inhalation. 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 a chemical apron. Wear appropriate protective clothing to prevent skin exposure.
Respirators
Wear a NIOSH/MSHA or European Standard EN 149 approved full-facepiece airline respirator in the positive pressure mode with emergency escape provisions. 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. 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.
Incompatibilities
Oxidizing agents
Decomposition
Carbon monoxide, irritating and toxic fumes and gases, carbon dioxide.

Fire.
Flash Point,°C
-45
Autoignition, °C
395
Upper exp. limit, %
12.1
Lower exp. limit, %
1.5
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Use water spray to keep fire-exposed containers cool. Containers may explode in the heat of a fire. Liquid will float and may reignite on the surface of water. Vapors may be heavier than air. They can spread along the ground and collect in low or confined areas. Will be easily ignited by heat, sparks or flame. 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. Use water spray to cool fire-exposed containers. Water may be ineffective. Do NOT use straight streams of water.
Fire potential
HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.
Hazards
Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers.
Combustion products
Vapor may travel considerable distance to a source of ignition and flashback.
Health
1
 
Flammability
3
 
 
Reactivity
1
 

Health.
Poison_Class
5
Exposure effects
The toxological properties of this substance have not been fully investigated.
   Ingestion
May cause gastrointestinal irritation with nausea, vomiting and diarrhea. May be harmful if swallowed.
   Inhalation
May cause respiratory tract irritation. Vapors may cause dizziness or suffocation.
   Skin
May cause skin irritation. May be harmful if absorbed through the skin.
   Eyes
May cause eye irritation.

First aid
 
   Ingestion
Never give anything by mouth to an unconscious person. Get medical aid. Do NOT induce vomiting. If conscious and alert, rinse mouth and drink 2-4 cupfuls of milk or water.
   Inhalation
Get medical aid immediately. Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen.
   Skin
Get medical aid. 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.

Transport.
UN number
2246
Response guide
Hazard class
3
Packing Group
II
 
USCG CHRIS Code
CPE
 
Std. Transport #
4909315
 
IMO Chemical Code
17
IMO Pollution Category
B
IMO Hazard code
P