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Nitric Acid Vapor

Nitric acid, or aqua fortis as it was called in medieval times, has been known and used by mankind for centuries. At first, it was produced by heating a mixture of sodium nitrate (Chile saltpeter) and sulfuric acid. The product obtained was sodium hydrogen sulfate, and the nitric acid vapors escaping during this process were condensed ... [Pg.85]

Salpetersaure. /. nitric acid, -anhydrid, n. nitric anhydride, (di)nitrogen pentoxide, nitrogen(V) oxide, -ather, m. nitric ether (ethyl nitrate), -bad, n. nitric acid bath, -dampf, m. nitric acid vapor or fume. [Pg.376]

The absorption of nitric acid vapor at 1.4u has been measured so that the equilibrium represented by Eq 5 could be studied H20(g) + 2N02(g) + l/203(g) 2HN03(g) (5)... [Pg.278]

The stratosphere is very dry clouds do not form at lower latitudes because the temperature is not low enough. However, the stratosphere over Antarctica is distinctive the temperature can drop to below -90 Celsius during the winter and spring months, leading to the condensation of water vapor and nitric acid vapor, that is, to the formation of ice clouds (polar stratospheric clouds or PSCs). [Pg.29]

The plate should be heated as rapidly and as evenly as possible after the first spraying step this is best done on a thick preheated aluminium plate in a drying cupboard equipped with ventilation allowing the nitric acid vapors to be removed using a water pump vacuum. Sodium dithionite is better than titanium(III) chloride or tin(II) chloride for the reduction of the nitro derivatives of amitrityline and nortriptyline. [Pg.58]

The second process, that of RGHg deposition together with particulate matter, has been addressed in various regional scale modeling studies for some time, but only recently has it been considered for direct measurement. Reactive gaseous Hg exhibits the characteristics of a so-called sticky gas and is cotmnonly modeled in the same fashion as nitric acid vapor (e.g., USEPA 1997 Bullock and Brehme 2002). [Pg.25]

The addition of a small amount of nitric acid vapor or nitric oxide accelerates the process. Invented by J. Hargreaves and T. Robinson in Widnes in 1870, in order to provide sodium sulfate for the Leblanc process, circumventing the need for the sulfuric acid used in the salt-cake section of that process. Reportedly still in use in 1984. [Pg.124]

Hass (1) A process for making aliphatic nitro-compounds from aliphatic hydrocarbons. The hydrocarbon vapor, mixed with nitric acid vapor, is passed through a narrow tube at 420°C. Invented by H. B. Hass in 1933. [Pg.124]

In the late 1960s, direct observations of substantial amounts (3ppb) of nitric acid vapor in the stratosphere were reported. Crutzen [118] reasoned that if HN03 vapor is present in the stratosphere, it could be broken down to a degree to the active oxides of nitrogen NO (NO and N02) and that these oxides could form a catalytic cycle (or the destruction of the ozone). Johnston and Whitten [119] first realized that if this were so, then supersonic aircraft flying in the stratosphere could wreak harm to the ozone balance in the stratosphere. Much of what appears in this section is drawn from an excellent review by Johnston and Whitten [119]. The most pertinent of the possible NO reactions in the atmosphere are... [Pg.487]

Ammonium nitrate dissociates in aqueous solution to NHj and NO3 ions. The former may be measured by ammonium ion-selective electrode and the latter by nitrate ion-selective electrode. The solid may be heated carefully at low temperature (around 90°C) and the evolved ammonia and nitric acid vapors are absorbed in water and measured by selective ion electrodes, respectively. [Pg.41]

Nitric acid obtained in standard ammonia oxidation is usually 50 to 70% by weight aqueous solution. Pure nitric acid of 98-99% may be obtained either by extractive distillation or by direct strong nitric (DSN) processes. In the distillation method, concentrated nitric acid of 50-70% is distilled with 93% sulfuric acid in a steam-heated tower. Sulfuric acid acts as a dehydrating agent. The distilled nitric acid vapor is condensed to pure nitric acid, while sulfuric acid absorbing water from 50-70% nitric acid loses its strength to about 70% and collects at the bottom. The 70% sulfuric acid is concentrated back to 93%... [Pg.637]

Buhr, S. M., M. P. Buhr, F. C. Fehsenfeld, J. S. Flolloway, U. Karst, R. B. Norton, D. D. Parrish, and R. E. Sievers, Development of a Semi-Continuous Method for the Measurement of Nitric Acid Vapor and Particulate Nitrate and Suflate, Atmos. Environ., 29, 2609-2624 (1995). [Pg.639]

Kulmala, M., A. Laaksonen, P. Korhonen, T. Vesala, T. Ahonen, and J. C. Barrett, The Effect of Atmospheric Nitric Acid Vapor on Cloud Condensation Nucleus Activation, J. Geophys. Res., 98, 22949-22958 (1993). [Pg.836]

French Compound. A substance of unknown composition obtained when dilute nitric acid reacts with a mixture of TNT and lead (or iron). French Compound easily ignites when brought into contact with nitric acid vapor at 100°, Either fragmentation or HE bombs can be loaded with this material and the method of loading is either lump or by compression of powdery. material. This material was used by Russions... [Pg.573]

Ferric Nitrate — Fire Hazards Flash Point (deg. F) Not flammable Flammable Limits in Air (%>) Not flammable Fire Extinguishing Agents Not pertinent Fire Extinguishing Agents Not To Be Used Not pertinent Special Hazards of Combustion Products Toxic oxides of nitrogen and nitric acid vapor may form in fires Behavior in Fire In contact with combustible materials, will increase the intensity of a fire Ignition Temperature (deg. F) Not pertinent Electrical Hazard Not pertinent ... [Pg.369]

ZEISBERG CONCENTRATOR. A nitric acid concentrator, consisting of a packed tower, into which weak nitric acid vapors are introduced. Some steam is admitted into the bottom, and strong nitric acid vapors are discharged from the top to a condenser. [Pg.1856]

ASTM B735, Std Test Methodfor Porosity in Gold Coatings on Metal Substrates by Nitric Acid Vapor, American Society for Testing and Materials, Philadelphia, Pa., 1992. [Pg.167]

Concentrated sulfuric acid Nitrates, N03 Solid nitrate with concentrated sulfuric acid evolves reddish brown vapors of nitrogen dioxide + nitric acid vapors when heated... [Pg.532]

The nitric acid vapors are led from the retort through a series of condensers and finally into absorption towers in which the acid is dissolved in water. The by-product sodium hydrogen sulfate is known as niter cake. Although it would seem reasonable to expect that this material might be used in a second reaction to produce more nitric acid,... [Pg.613]

Sulfur dioxide is produced by burning either sulfur or a sulfide such as pyrite in the furnace. The dioxide is then mixed with the catalyst, NO, which may be prepared in either of two ways. In the older method, nitric acid vapor is formed in the niter pot, and when this vapor comes into contact with sulfur dioxide, nitric oxide is formed in accordance with the following equation ... [Pg.616]

Vapor-phase nitration of paraffin hydrocarbons, particularly propane, can be brought about by uncatalyzed contact between a large excess of hydrocarbon and nitric acid vapor at around 400°C, followed by quenching. A multiplicity of nitrated and oxidized products results from nitrating propane nitromethane, nitroethane, nitropropanes, and carbon dioxide all appear, but yields of useful products are fair. Materials of construction must be very oxidation-resistant and are usually of ceramic-lined steel. The nitroparaffins have found limited use as fuels for race cars, submarines, and model airplanes. Their reduction products, the amines, and other hydroxyl compounds resulting from aldol condensations have made a great many new aliphatic syntheses possible because of their ready reactivity. [Pg.621]

The oldest nitric acid production method involved the reaction of NaNOj with sulfuric acid in heated cast iron retorts. The evolved nitric acid vapors were condensed and collected in stoneware vessels. [Pg.215]


See other pages where Nitric Acid Vapor is mentioned: [Pg.15]    [Pg.179]    [Pg.171]    [Pg.172]    [Pg.172]    [Pg.173]    [Pg.173]    [Pg.413]    [Pg.414]    [Pg.742]    [Pg.906]    [Pg.907]    [Pg.50]    [Pg.513]    [Pg.552]    [Pg.194]    [Pg.145]    [Pg.226]    [Pg.505]    [Pg.505]    [Pg.508]    [Pg.300]   


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