Smoke white

White pine White rust White s agar White Shoulders White smoke Whitewares Whitewash White water Whitfield s Ointment... 

Boron trifluoride [7637-07-2] (trifluoroborane), BF, was first reported in 1809 by Gay-Lussac and Thenard (1) who prepared it by the reaction of boric acid and fluorspar at duU red heat. It is a colorless gas when dry, but fumes in the presence of moisture yielding a dense white smoke of irritating, pungent odor. It is widely used as an acid catalyst (2) for many types of organic reactions, especially for the production of polymer and petroleum (qv) products. The gas was first produced commercially in 1936 by the Harshaw Chemical Co. (see also Boron COMPOUNDS). 

Other uses of hexachloroethane are as moth repellent, plasticizer for cellulose esters, anthelmintic in veterinary medicine, mbber accelerator, and as a component in fungicidal and insecticidal formulations. Hexachloroethane reacts with silumin (an aluminum /siUcon alloy) at 483 K to generate an intense white smoke, which is useful in certain pyrotechnics (154). 

Smokes and plumes White smoke (liquid mist) Plume abatement 0.3-0.5 800-10001... 

Coloured smoke compositions White smoke compositions (except those in Group 5) Compositions with <35% chlorate... 

White smoke compositions based on hexachloroethane with zinc, zinc oxide and <5% aluminium or <10% calcium silicon... 

Coloured smoke devices Sealed table bombs White smoke devices... 

FIGURE 10.80 A typical Aaberg ventilator unit. v[Pg.959]

Smoke pellets are produced in a range of sizes and are commonly used tor the resting of household flues and chimneys. The pellet is ignited and will burn for about 10 seconds producing a dense white smoke. Because this is a combustion process there are obvious restrictions on its use (nonflammable atmo spheres, nonflammable surfaces, etc.). In addition the smoke is buoyant because of the heat generated. The smoke can also be an irritant and/or toxic. The production of smoke cannot be controlled, but pellets are inexpensive, easy to use, and readily available, and the smoke is produced in sufficient quantities to make them useful in the evaluation, for example, of fume cupboards and Ixroths. 

The white "smoke" around a piece of dry ice is C02[fir), formed by sublimation. 

Magnesium metal burns in air, emitting enough light to be useful as a flare, and forming clouds of white smoke. Write the equation for the reaction. What is the composition of the smoke ... 

Obscuring Power of White Smokes. The total obscuring power, TOP, of a white smoke agent used for screening purposes, is obtained by multiplying the product of volume, in cubic ft or smoke produced per lb of material, and the reciprocal of the smoke layer, in ft, necessary to obscure the filament of a 40-watt Mazda lamp. The TOP for some white smoke agents, at low altitudes where atm constituents are plentiful, is given in Table 1... 

The so-called standard smoke is a smoke of such a density that a 25-candlepower light is just invisible when observed thru a layer 100 ft thick, A comparison of some white smoke agents at low altitude, where atm constituents are plentiful, in terms of the amount of smoke agent required to produce 1000 cubic ft of standard smoke, is given in Table 2... 

Composition For White Smoke Puff Ground Troop Signals , PATR 134 (1931). 5) Ibid,... 

A mixt of 50—80 parts of sulfamic ac and 50—20 parts of AP evolves copious amts of smoke on ign (Ref 20), A similar mixt of 390 parts of Zn oxide, 375 parts of hexachloroethane, and 190 parts of AP is slurried in a soln of 40 parts of polyvinyl acetate in 200 parts of mete chloride. The mixt is packed into cylinders, the solv evapu, and ignited to give copious amis of white smoke with a burning time of 68 secs (Ref 26) Refs 1) Gmelin, System No 23 (1936), 196 2) G.S. Serullas, AnnChimPhys (2) 46, 304... 

Red P has been employed as an ingredient of pyrotechnic smoke, delay and safety match formulations (Refs 1,2,3 4). White smoke consisting of small droplets of phosphoric acid have been widely used for military purposes. 

If flue gas (exit gas) emerging from a stack is black and smoky, it is an indication of insufficient air. If the gas emerging is a white smoke, it is an indication of a considerable excess of air. Ideally, the gas should be colorless to very slightly brown, with a minimum of haze. 

FIGURE 15.23 The white smoke emitted by the shuttle booster rockets consists of powdered aluminum oxide and aluminum chloride. 

White smoke compositions speed burning without flash ignitions/... 

White smoke compositions Signal ammunition in explosions... 

Test Hibe 1 6 M HC1 Had to be a strong acid since when mixed with tube 3 it got hot and I had already identified tube 3 as NH3 by odor. When mixed with samples from test tube 2, the reaction produced a great deal of heat, therefore tube 1 had to contain a strong acid. Could be either 6 M HC1 or 3 M H2S04. When mixed with test tube 3, a white smoke was produced. I concluded that the smoke was NH4C1, therefore, by default, test tube 1 had to contain 6 M HC1. To confirm that this test tube contained HC1,1 mixed samples from test tube 1 with test tube 10, which I believed to contain Ag+ from prior data in the table, and a white precipitate of AgCl was formed. 

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