Lead II Azide

DOT Label Class A Explosive. Forbidden (dry) when wetted with not less than 20% by weight water or mixed with mixture of water and alcohol, it is labeled Explosive 

Lead azide is used as a primary explosive in detonators and fuses to initiate the booster or bursting charge. Generally, it is used in dextrinated form. Lead azide is also used in shells, cartridges, and percussion caps. 

Toxicity data for lead azide are not available. Its aqueous solution is toxic, exhibiting poisoning effect of lead. 

Lead azide is a primary explosive. Its detonation temperature is 350°C (662°F), and the detonation velocity is 5.1 km/s (Meyer 

Its heat of combustion and heat of detonation are 631 and 368 cal/g, respectively (or 184 and 107 kcal/mol). The released gas volume is 308 cm /g at STP. It forms highly shock-sensitive copper and zinc azides when mixed with the solutions of copper and zinc salts. Its contact with these metals or then-alloys over a period of time results in the formation of their azides, too. Reaction with carbon disulfide is violently explosive. There is a report of an explosion resulting from the addition of calcium stearate in a lead azide preparation (MCA 1962). 

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The crystalline product appears less stable than the diazide, spontaneously decomposing, sometimes explosively [1], It was rated as too unstable for use as a practical detonator or explosive [2], Lead(IV) acetate azide (probably the triacetate azide) is also rather unstable, evolving nitrogen above 0°C with precipitation of lead(II) azide [3], Lead(IV) azide will be considerably more endothermic than the lead(II) salt. 

Lead(II) azide Lead chromate Lead dioxide Calcium stearate, copper, zinc, brass, carbon disulfide Iron hexacyanoferrate(4-) Aluminum carbide, hydrogen peroxide, hydrogen sulfide, hydroxylamine, ni-troalkanes, nitrogen compounds, nonmetal halides, peroxoformic acid, phosphorus, phosphorus trichloride, potassium, sulfur, sulfur dioxide, sulfides,... 

Hexaazido-2,4,6-triaza-1,3,5-triphosphorine, 4795 Hydrogen azide, 4441 f Hydrogen selenide, 4486 f Hydrogen telluride, 4488 Iodoform, 0376 Lead(II) azide, 4782 Lead(IV) azide, 4790 Mercury(II) cyanide, 0976 Mercury(II) fulminate, 0978... 

Lead(IV) acetate azide, 2402 Lead (II) azide, 4782 Lead(IV) azide, 4790 Lithium azide, 4685... 

Explosives are generally categorized as either primary or secondary, depending on their sensitivity to shock. Primary explosives are the most sensitive to heat and shock. They are generally used in detonators, blasting caps, and military fuses to initiate the explosion of the less-sensitive secondary explosives. Mercury(II) fulminate, Hg(ONC)2, was the first initiator to be used commercially, but it has been largely replaced by lead(II) azide, Pb(N3)2, which is more stable when stored under hot conditions. 

LZ. Lead azide plumbous azide lead-II-azide... 

These compounds contain other ligands besides the azide group principal types of the class are basic azides and azide halides. The former are obtained by hydrolysis when preparing the III A through VIII metal azides in aqueous media hence, the stoichiometry of these products fluctuates with experimental circumstances. Nonetheless, stoichiometric phases of 22 basic azides are established, such as nickel hydroxide azide, (OH)Ni(N3), and holmium hydroxide azide, (HO)2Ho—O—Ho(OH)(N3). Azide halides have been made of the III through VII metals and of some adjacent metalloids examples are, lead(II) azide chloride, ClPb(N3), and boron azide dichloride, Cl2B(N3). 

Other basic azides were made by treating lead azide with sodium hydroxide solution, or precipitating lead salts with sodium azide/hydroxide mixtures. Altogether, nine phases are distinguished by X-ray analysis [297,298]. A lead(II) azide chloride, ClPb(N3), is similarly obtained from lead nitrate and azide/ chloride mixtures [270,292] as a white solid of reduced explosivity relative to lead azide. 

Although satisfactory methods for the preparation of lead(II) azide, Pb(Nj)2, are available in the literature, there is no authentic isolation of lead(IV) azide, Pb(Ns) . The isolation of lead(IV) chloride suggests the existence of lead(IV) azide, but the work of Moller and Lieber has thus far indicated only its qualitative existence without its successful isolation and characterization. Lieber and Keane were the first to attempt the synthesis of lead(IV) azides of the types RaPbNs, R Pb(N3)2, and RPb(Ns)a, in which R is a group that can stabilize the lead-nitrogen linkage and thus produce a stable derivative of the azide of tetravalent lead. This expectation was realized for the case in which R is a phenyl group. 

Klapdtke, M, Sabate, C.M., Welch, J.M. Alkali metal 5-nitrotetrazolate salts prospective replacements for service lead(II) azide in explosive initiators. Dalton Trans. 6372-6380 (2008)... 

Detonators are also commonly nitrogen compounds, with the mostwidelyused being lead(II) azide, Pb(N3)2, readily exploded by an electrical current or mechanical shock. The azide ion, Nj, is isoelectronic and isostructural with carbon dioxide. 

Lead(II) azide is discussed with the pseudohalides, and lead nitrides are not known. 

Both a- and -forms of lead(II) azide are very sensitive to shock and to thermal decomposition, but the activation energy for decomposition of the / -form is considerably lower than that of the a-form, and at about 260°C the violence of detonation of the)8-form is about twenty times greater than that of the a-form227. 

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