Nitrous oxide

  • Dinitrogen monoxide
  • Laughing gas
  • Dinitrogen oxide
Formula
N2O
Structure
Description
A colorless liquid. Shipped under refrigeration.
Uses
To oxidize organic compound at temp above 300 deg c, make nitrites from alkali metals at their boiling points, in rocket fuel formulations (with carbon disulfide), in prepn of whipped cream.

Registry Numbers and Inventories.
CAS
10024-97-2
EC (EINECS/ELINCS)
233-032-0
RTECS
QX1350000
RTECS class
Tumorigen; Mutagen; Reproductive Effector; Human Data
UN (DOT)
2201
Merck
12,6751
Beilstein/Gmelin
805 (G)
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
N2O
Formula mass
44.01
Melting point, °C
-99
Boiling point, °C
-88.6
Vapor pressure, mmHg
42900 (25 C)
Vapor density (air=1)
1.53
Critical temperature
36.5
Critical pressure
71.7
Density
1.266 g/cm3 (20 C)
Solubility in water
1 g/L
Viscosity
0.0145 cp at 25C at 1 atm
Surface tension
1.75 g/s2 at 20 C in contact with vapor
Refractive index
1.330
Dipole moment
0.14 D
Dielectric constant
1.45 (30 C)
Partition coefficient, pKow
-1.28
Heat of fusion
6.5 kJ/mol
Heat of vaporization
16.5 kJ/mol

Hazards and Protection.
Storage
Keep in a cool, dry, dark location in a tightly sealed container or cylinder. Keep away from incompatible materials, ignition sources and untrained individuals. Secure and label area. Protect containers/cylinders from physical damage.
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
Wear appropriate protective gloves, clothing and goggles. Always wear thermal protective clothing when handling refrigerated/cryogenic liquids.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
Keep material out of water sources and sewers. Attempt to stop leak if without undue personnel hazard. Use water spray to knock-down vapors.
Stability
Moderate, can form explosive mixture with air reactive only under extreme conditions.
Incompatibilities
Explosions have occurred with ether-nitrous oxide mixtures. Spontaneous ignition occurs when nitrous oxide and lithium hydride or hydrazine are mixed.

Fire.
Fire fighting
Do not use water. Dangerously explosive. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible.
Fire potential
Substance does not burn but will support combustion.
Hazards
Some may react explosively with fuels. May ignite combustibles (wood, paper, oil, clothing, etc.). Vapors from liquefied gas are initially heavier than air and spread along ground. Runoff may create fire or explosion hazard. Containers may explode when heated. Ruptured cylinders may rocket.

Health.
Exposure limit(s)
TLV: 50 ppm; 90 mg/m3 as TWA (ACGIH 1991-1992). NIOSH REL: TWA 25 ppm (46 mg/m3) (TWA over the time exposed) *Note: REL for exposure to waste anesthetic gas.
Exposure effects
Signs and symptoms of asphyxia include headache, dizziness, excitation proceeding to possible CNS depression, seizures, and death. Intracranial pressure may be elevated. SPERMATOGENESIS - Suppression of spermatogenesis was noted in male rats exposed to 20% nitrous oxide, 20% oxygen, and 60% nitrogen for up to 35 days. It took 3 to 6 days for sperm production to recover after exposure was discontinued (Kripke et al, 1976).
   Inhalation
Vapors may cause dizziness or asphyxiation without warning.
   Skin
Contact with gas or liquefied gas may cause burns, severe injury and/or frostbite.
   Eyes
See Skin.

First aid
 
   Ingestion
Seek medical assistance.
   Inhalation
Move victim to fresh air. Apply artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; induce artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult.
   Skin
Remove and isolate contaminated clothing and shoes. Immediately flush with running water for at least 20 minutes. In case of contact with liquefied gas, thaw frosted parts with lukewarm water.
   Eyes
Immediately flush with running water for at least 20 minutes.

Transport.
UN number
2201
Response guide
Hazard class
2.2
USCG CHRIS Code
NTO
 
Std. Transport #
4904345