Nitrous oxide, compressed

SYNS DINITROGEN MONOXIDE FACTITIOUS AIR HYPONITROUS ACID ANHYDRIDE LAUGHING GAS NITROUS OXIDE (DOT) NITROUS OXIDE, compressed (UN 1070) (DOT) NITROUS OXIDE, refrigerated liquid (LIN 2201) (DOT)... 

GAS nitrous oxide NITROUS OXIDE, COMPRESSED NITROUS OXIDE, REFRIGERATED LIQUID... 

Synonyms Dinitrogen monoxide Dinitrogen oxide Factitious air Hyponitrous acid anhydride Laughing gas Nitrogen monoxide Nitrogen oxide Nitrous oxide, compressed Nitrous oxide, refrigerated liquid... 

DOT Label NON-FLAMMABLE GAS, OXIDIZER TC Shipping Name Nitrous oxide, compressed... 

CGA 6-8.2, Commodity Specification for Nitrous Oxide, Compressed Gas Association, Inc., 1235 Jefferson Davis Highway, Arlington, VA 22202. 

Nitrous Oxide, compressed 1070 14 Organic Peroxide Type B. solid 3102 49... 

HYDROGEN BROMIDE, anhydrous 1070 14 NITROUS OXIDE, compressed... 

Propellants. The propellant, said to be the heart of an aerosol system, maintains a suitable pressure within the container and expels the product once the valve is opened. Propellants may be either a Hquefied halocarbon, hydrocarbon, or halocarbon—hydrocarbon blend, or a compressed gas such as carbon dioxide (qv), nitrogen (qv), or nitrous oxide. 

Considerable developmental effort is being devoted to aerosol formulations using the compressed gases given in Table 4. These propellants are used in some food and industrial aerosols. Carbon dioxide and nitrous oxide, which tend to be more soluble, are often preferred. When some of the compressed gas dissolves in the product concentrate, there is partial replenishment of the headspace as the gas is expelled. Hence, the greater the gas solubiUty, the more gas is available to maintain the initial conditions. 

FIG. 2-14 MoUier diagram for nitrous oxide. (Fig. 9, Cfniv. Texas Rep., Cont. DAI-23-072-ORD-685, June 1, 1956, hy Couch and Kobe. Reproduced hy permission.) Some irregularity in the compressibility factors from 80 to 160 atm, 50 to 100 C exists (Couch, private communication, 1.967). See Couch et al.,y, Chem. Eng. Data, 6, (1961) for P -T data. 

Hart and Henglein [14] also reported the sonolytic decomposition of nitrous oxide in aqueous solutions under pure argon, pure N2O and the mixture of the two gases and reported the formation of species such as N2, O2, N02 and N03 with the maximum yield being in the Ar/N20 mixture in the vol% ratio of 85 15. Although H20 is thermodynamically much more stable than N2O but they postulated that all H20 and N2O molecules in an argon bubble were converted into free radicals in the short time of adiabatic compression phase of the bubble. They proposed a series of free radical reactions for the formation of all these species in aqueous solutions. 

The sources of acetylene, nitrous oxide, and sometimes air are usually steel cylinders of the compressed gases purchased from specialty gas or welders gas suppliers. Thus, several compressed gas cylinders are usually found next to atomic absorption instrumentation and the analyst becomes involved in replacing empty cylinders with full ones periodically. Safety issues relating to storage, transportation, and use of these cylinders will be addressed in Section 9.3.7. The acetylene required for atomic absorption is a purer grade of acetylene than that which welders use. 

Nitrous oxide occurs naturally and is a colourless slightly sweet-smelling non-irritant gas with the molecular weight of 44 (Table 3.3). Its boiling point is -89°C and it is compressible to a colourless liquid. The gas is stable in the presence of soda-lime and whilst it will support combustion of other agents it is neither flammable nor explosive itself. 

In 1732, H, Boerhaave 11 tried without success to condense air to the liquid state by artificial cold and in 1850, J. Natterer likewise failed in an attempted liquefaction of air, although he compressed the gas under nearly 3000 atm. press. but in 1877, L. Cailletet obtained liquid air in the form of a mist by compressing dried air, freed from carbon dioxide, at the temp, of liquid nitrous oxide, and under 200-225 atm. press., and suddenly releasing the press. and in 1884, J. Dewar described a method of liquefying air cooled by means of liquid or solid nitrous oxide —vide 1. 13, 25. Various forms of apparatus have been devised for liquefying air... 

Nitrous oxide gas is easily liquefied. In 1823, M. Faraday10 heated thoroughly dried ammonium nitrate in one leg of a A-tube, and on cooling the other leg of the tube, obtained two liquids one a soln. of nitrous oxide in water, and the other water in nitrous oxide. It is doubtful if J. H. Niemann prepared the liquid gas in in this way. The liquefaction by compression and cooling has been described by... 

Companies in both America and the United Kingdom succeed in producing compressed and liquid nitrous oxide in cylinders. 

Nitrous oxide is synthesized, or produced, by heating ammonium nitrate (NH4N03) and then condensing out the water and filtering impurities. The gas is then compressed and turned into liquid for storage in tanks, cylinders, or cartridges. 

Medical grade nitrous oxide is a prescription drug sold as a compressed liquid in cylinder tanks. Its buyer requires appropriate credentials to obtain it (which are governed by state law). Nitrous oxide used for other legitimate applications, such as manufacturing and auto racing, is often sold in a denatured form. Denatured nitrous contains chemicals that render it unfit for human consumption. 

Also, working with any compressed gas may be dangerous. Although nitrous oxide itself is not flammable, the pressurized contents can explode and cause serious injury if a gas tank or cylinder is improperly stored, or is dropped, knocked over, or punctured. 

Use of the medical grade gas is by prescription only, and regulated by the FDA. Compressed medical gas suppliers must register with FDA, and are subjected to facility inspections from FDA at least once every two years. Licenses required to purchase and administer nitrous oxide in the healthcare setting is regulated on a state level. 

A number of compressed and liquified gases are used as refrigerants and aerosol propellants. These include nitrous oxide, nitrogen, carbon dioxide, propane, and butane. The use of chlorofluorocarbons (CFCs) is restricted because of environmental pollution leading to health hazards. These have been replaced by hydrogenated fluorocarbons (HFCs), which are less likely to cause environmental pollution. 

Nitrous oxide is contained and transported in its liquid phase in high-pressure gas cylinders or in liquid cylinders. It is transported as a liquefied compressed gas under high pressure in cylinders and at lower pressures and reduced temperatures in refrigerated cargo tanks and insulated portable tanks. Nitrous oxide is stored in a foam-insulated tank accompanied by a refrigeration unit, which is similar to the tank used for carbon dioxide. 

Coan, C.R. and A.D. King. 1971. Solubility of water in compressed carbon dioxide, nitrous oxide, and ethane. Evidence for hydration of carbon dioxide and nitrous oxide in the gas phase. /. Am. Chem. Soc. 98 1857-1862. 

Carbon dioxide and other compressed gases such as nitrogen and nitrous oxide are used as propellants for topical pharmaceutical aerosols. They are also used in other aerosol products that work satisfactorily with the coarse aerosol spray that is produced with compressed gases, e.g., cosmetics, furniture polish, and window cleaners. ... 

Nitrous oxide is a nonflammable, colorless and odorless, sweettasting gas. It is usually handled as a compressed gas, stored in metal cylinders. 

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