Mixture in air

Carbon disulphide is a volatile, evil-smelling liquid, although if carefully purified, the unpleasant smell is removed, as it is due to impurity. The vapour is inflammable and can form explosive mixtures in air ... 

Revised material in Section 5 includes an extensive tabulation of binary and ternary azeotropes comprising approximately 850 entries. Over 975 compounds have values listed for viscosity, dielectric constant, dipole moment, and surface tension. Whenever possible, data for viscosity and dielectric constant are provided at two temperatures to permit interpolation for intermediate temperatures and also to permit limited extrapolation of the data. The dipole moments are often listed for different physical states. Values for surface tension can be calculated over a range of temperatures from two constants that can be fitted into a linear equation. Also extensively revised and expanded are the properties of combustible mixtures in air. A table of triple points has been added. 

Stabilized tetrachloroethylene, as provided commercially, can be used in the presence of air, water, and light, in contact with common materials of constmction, at temperatures up to about 140°C. It resists hydrolysis at temperatures up to 150°C (2). However, the unstabilized compound, in the presence of water for prolonged periods, slowly hydrolyzes to yield trichloroacetic acid [76-03-9] and hydrochloric acid. In the absence of catalysts, air, or moisture, tetrachloroethylene is stable to about 500°C. Although it does not have a flash point or form flammable mixtures in air or oxygen, thermal decomposition results in the formation of hydrogen chloride and phosgene [75-44-5] (3). 

These ai e, of course, the limits for the air-free mixture. But remember, the original mixture, before we removed the air, had 2% O2. So the lower limit for the original mixture (with the air added back) is 25.4% + 2/0.209 = 35.0 (the increased lower limit means greater percentage of the combustible mixture in air or lower percentage of air required with the combustible mixture to cause combustion). It is logical that less air is needed since the original mixture (with the air added back) has a head start on combustion (with the contained 2% O2). 

Extinguishing Agents Dry chemical, carbon dioxide, water fog, chemical foam Fire Extinguishing Agents Not To Be Used None Special Hazards of Combustion Products Not pertinent Behavior in Fire Vapor from molten benzoic acid may form explosive mixture with air. Concentrated dust may form explosive mixture in air Ignition Temperature (deg. F) 1,063 Electrical Hazard Not pertinent Burning Rate Not pertinent. 

Fire Hazards - Flash Point Not pertinent. This is a combustible solid Flammable Limits in Air (%) Not pertinent Fire Extinguishing Agents Water, dry powder, foam, or carbon dioxide Fire Extinguishing Agents Not To Be Used None fecial Hazard of Combustion Products None Behavior in Fire Dust forms explosive mixture in air Ignition Temperature No data Electrical Hazard Not pertinent Bunting Rate Not pertinent. 

Flammable limits are affected by both temperature and pressure. In general, as the temperature of a gas mixture increases, the size of the flammability zone increases. For mixtures in air, the UFL increases and the... 

Notr The above data are from tests in a straight 3-inch diameter pipe using a test gas consisting of 4.3 volume percent propane mixture in air, initially at 23 psia. 

The partially reduced form of niobium accounts for the color change of samples that underwent thermal treatment in vacuum or inert atmospheres. Whereas the thermal treatment of the mixture in air leads to the simultaneous oxidation of Nb4+ by oxygen, this is actually equivalent to the replacement of fluorine ions by oxygen ions in the complex structure of oxyfluoroniobate. Extended thermal treatment of systems containing LiNbOF4 and LiF yields a mixture of LiF and LiNbOs as the final thermal decomposition product. 

EXPLOSION Finely dispersed particles form explosive mixtures in air. Prevent deposition of dust closed system, dust explosion-proof electrical equipment and lighting. Prevent build-up of electrostatic charges (e.g., by grounding). ... 

The general reactivity of the sulfide depends markedly on the physical form, and differences of a factor of 10 may be involved. It is ignitable by friction, sparks or flames, and ignites in dry air if heated close to the m.p., 275 -280°C. The dust (200 mesh) forms explosive mixtures in air above a concentration of 0.5% w/v [1], and maximum explosion pressures of 4.35 bar, with maximum rate of rise exceeding 680 bar/s have been determined [2], The dust can acquire sufficient static electricity from movement for ignition to occur [3],... 

Volatile decomposition products may include HC1, HBr, HF, and nitrogen oxides (NO ) or sulfur oxides (SO ). Decomposition vapors from nitrogen vesicants may form explosive mixtures in air. In addition, a corrosive and toxic residue may remain. HL (C03-A010) will also produce toxic arsenic oxides. 

Flash Point is given in degrees Celsius, usually using a closed cup. When the method is known, the acronym appears in parentheses after the value closed cup (CC), Cleveland closed cup (CCC), open cup (OC), Tag closed cup (TCC), and Tag open cup (TOC). Because values will vary with the specific procedure employed, and many times the method was not stated, the values listed for the flash point should be considered only as indicative. See also Table 5.23, Properties of Combustible Mixtures in Air. 

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