Ketene

  • Ethenone
  • Carbomethene
  • Ketoethylene
Formula CH2=C=O
Structure
Description Colorless gas. Penetrating odor.
Uses Conversion of higher acids into their anhydrides.

Registry Numbers and Inventories.
CAS 463-51-4
EC (EINECS/ELINCS) 207-336-9
RTECS OA7700000
RTECS class Other
Merck 12,5309
Beilstein/Gmelin 1098282
Beilstein Reference 4-01-00-03418
Swiss Giftliste 1 G-3993
Canada DSL/NDSL NDSL
US TSCA Listed
Austrailia AICS Listed
New Zealand Listed
Japan ENCS (MITI) Listed
Korea ECL Listed

Properties.
Formula C2H2O
Formula mass 42.04
Melting point, °C -134.1
Boiling point, °C -56
Vapor pressure, mmHg 12600 (25 C)
Vapor density (air=1) 1.45
Density 0.65 g/cm3 (-60 C)
Solubility in water Very soluble
Refractive index 1.4355 (20 C)
Partition coefficient, pKow 0.11
Heat of vaporization 20.2 kJ/mol
Heat of combustion -1025.4 kJ/mol

Hazards and Protection.
Storage Cannot be atored in a gaseous state. Protect containers against physical damage by shock. Outdoor or detached storage is preferable. For indoor storage, use standard combustible liquid storeroom or cabinet.
Handling All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection Chemical splash goggles in compliance with OSHA regulations are advised; however, OSHA regulations also permit other type safety glasses. Whre chemical resistant gloves. To prevent repeated or prolonged skin contact, wear impervious clothing and boots.
Respirators Use NIOSH/MSHA approved respirator appropriate for exposure of concern.
Small spills/leaks Evacuate area and ventilate. Wear protective equipment. If required, use an inert absrobent. Sweep up and place in an appropriate container for disposal. Wash contaminated surfaces.
Stability No data.
Incompatibilities Strong oxidizing agents.
Decomposition Substance may readily polymerize. Reacts violently with many organic compounds.

Fire.
Flash Point,°C -107
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. Use agent most appropriate to extinguish fire.
NFPA Health 3

Health.
Exposure limit(s) OSHA PEL: TWA 0.5 ppm (0.9 mg/m3) NIOSH REL: TWA 0.5 ppm (0.9 mg/m3) ST 1.5 ppm (3 mg/m3) NIOSH IDLH: 5 ppm
Poison_Class 1
Exposure effects
   Ingestion Nausea and vomiting may occur.
   Inhalation Irritation of the upper airways, cough, burning sensation of the throat, dyspnea, pain in the chest and severe, delayed pulmonary edema can occur. Respiratory failure can result after significant exposures.
   Skin Severe dermal burns or frostbite may develop following skin exposure to the liquefied material.

First aid		  
   Ingestion Seek medical attention. If individual is drowsy or unconscious, do not give anything by mouth; place individual on the left side with the head down. Contact a physician, medical facility, or poison control center for advice about whether to induce vomiting. If possible, do not leave individual unattended.
   Inhalation If symptoms develop, move individual away from exposure and into fresh air. If symptoms persist, seek medical attention. If breathing is difficult, administer oxygen. Keep person warm and quiet; seek immediate medical attention.
   Skin Remove contaminated clothing. Wash exposed area with soap and water. If symptoms persist, seek medical attention. Launder clothing before reuse.
   Eyes If symptoms develop, immediately move individual away from exposure and into fresh air. Flush eyes gently with water for at least 15 minutes while holding eyelids apart; seek immediate medical attention.

Transport.