Flammable gases vapor density

Vapor Density (VD) — the mass per unit volume of a given vapor/gas relative to that of air. Thus, acetaldehyde with a vapor density of 1.5 is heavier than air and will accumulate in low spots, while acetylene with a vapor density of 0.9 is lighter than air and will rise and disperse. Heavy vapors present a particular hazard because of the way they accumulate if toxic they may poison workers if nontoxic they may displace air and cause suffocation by oxygen deficiency if flammable, once presented with an ignition source, they represent a fire or explosion hazard. Gases heavier than air include carbon dioxide, chlorine, hydrogen sulfide, and sulfur dioxide. 

Carbonyl sulfide is a flammable gas, and may be explosive or spontaneously flammable in air under the right conditions. Vapors may ignite at distant ignition sources and flash back. When exposed to fire, humidity, or strong alkalis, carbonyl sulfide may form the toxic decomposition products carbon monoxide and hydrogen sulfide gas. In the presence of strong oxidizers, carbonyl sulfide presents a fire or explosion hazard. Carbonyl sulfide has a vapor density of 2.1 and is therefore heavier than air. Cylinders or tank cars containing carbonyl sulfide may rupture violently or rocket under fire conditions. 

High airborne concentrations of ethyiamine can form, given its vapor pressure, with the potential for severe eye, nose, and respiratory tract irritation escape impairment and possible death. The immediately dangerous to life or health (IDLH) concentration for ethyiamine is 600 ppm. Anhydrous ethyiamine is a flammable gas aqueous ethyiamine is a flammable liquid. Vapors can travel a considerable distance to an ignition source and flash back because ethyiamine vapor density is heavier than air. 

Physical changes involve changes in the physical state of the chemical, bnt do not produce a new substance, snch as the physical transformation from a liqnid to a gas or a liquid to a solid. Physical properties include specific gravity, vapor pressure, boiling point, vapor density, melting point, solubility, flash point, fire point, auto-ignition temperatnre, flammable range, heat content, pH, threshold limit valne (TLV), and permissible exposnre level (PEL). 

Dimethylamine, (CH3)2NH, an amine hydrocarbon derivative, is a gas with an ammonia-like odor. It is a dangerous fire risk, with a flammable range of 2.8 to 14% in air. It is insoluble in water. The vapor density is 1.55, which is heavier than air. The boiling point is 44°F, and the ignition temperature is 806°F. Dimethylamine is an irritant, with a TLV of 10 ppm in air. The four-digit UN identification number is 1032. The NFPA 704 designation is health 3, flammability 4, and reactivity 0. The... 

Propylene, CjH (propene), has a boiling point of -53°F. The flammable range of propylene is 2 to 11%. The vapor density is 1.46, which is heavier than air. The four-digit UN identification number is 1077. The NFPA 704 designation is health 1, flammability 4, and reactivity 1. It is not toxic, but can be an asphyxiant gas by displacing the oxygen in the air. It is usually shipped as a pressurized liquid in cylinders, tank cars, and tank barges. The structure for propylene is shown in the Alkene section of this chapter. 

Boron trifluoride, BFj, is a colorless gas with a vapor density of 2.34, which is heavier than air. It is water-soluble and does not support combustion. It is also water-reactive, toxic by inhalation, and corrosive to skin and tissue. The TLV is 1 ppm, and the IDLH is 100 ppm in air. The boiling point is -148°F. The four-digit UN identification number is 1008. The NFPA 704 designation is health 4, flammability 0, and reactivity 1. The primary uses are as a catalyst in organic synthesis, in instruments for measuring neutron intensity, in soldering fluxes, and in gas brazing. 

Flammable gas ignites with moist air at room temperarnre vapor density 0.96 (air =... 

Boiling point, °C 138 Melting point, C -78 Flash point, C 33 Auto-ignitlon temperature, ° C 300 Relative density (water -1) 0.8 Relative vapor density (air-1) 3.0 Relative density at 20 ° C of saturated mixture vapor/air(air-1) 1.01 Vapor pressure, mm Hg at 20 C 2.3 Solubility in water, g/100 ml 2.7 Explosive limits, vol% in air 1.3-10.5 Electrical conductivity, pS/m 2.6 x 10 Relative molecular mass 88.1 Log P octanol/water 1.3 Grossformula 5 12 COLORLESS LIQUID WITH CHARACTERISTIC ODOR Vapor mixes readily with air. Reacts violently with oxidants, with risk of fire and explosion. Reacts violently with alkaline-earth and alkali metals, giving off flammable gas (- hydrogen). ... 

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