Lead(II) azide

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Lead(II) azide
Skeletal formula of lead(II) azide
Lead(II) azide (modified beta)
Identifiers
CAS number 13424-46-9 YesY
PubChem 61600
ChemSpider 55508
EC number 236-542-1
UN number 0129
Jmol-3D images Image 1
Properties
Molecular formula N6Pb
Molar mass 291.24 g mol−1
Appearance White powder
Density 4.71 g/cm3
Melting point 190 °C (374 °F; 463 K) decomposes,[2] explodes at 350 °C[1]
Solubility in water 2.3 g/100 mL (18 °C)
9.0 g/100 mL (70 °C)[1]
Solubility Very soluble in acetic acid
Insoluble in ammonia solution,[1] NH4OH[2]
Thermochemistry
Std enthalpy of
formation
ΔfHo298
462.3 kJ/mol[1]
Explosive data
Shock sensitivity High
Friction sensitivity High
Detonation velocity 5180 m/s
Hazards
GHS pictograms The exploding-bomb pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS)The exclamation-mark pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS)The health hazard pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS)The environment pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS)[3]
GHS signal word Danger
GHS hazard statements H200, H302, H332, H360, H373, H400, H410[3]
EU classification Toxic T Harmful Xn Explosive E Dangerous for the Environment (Nature) N
R-phrases R3, R20/22, R33, R50/53, R61, R62, R62
Main hazards Harmful, explosive
NFPA 704
Flammability code 0: Will not burn. E.g., water Health code 3: Short exposure could cause serious temporary or residual injury. E.g., chlorine gas Reactivity code 3: Capable of detonation or explosive decomposition but requires a strong initiating source, must be heated under confinement before initiation, reacts explosively with water, or will detonate if severely shocked. E.g., fluorine Special hazards (white): no codeNFPA 704 four-colored diamond
Autoignition temperature 350 °C (662 °F; 623 K)
Related compounds
Other cations Potassium azide
Sodium azide
Copper(II) azide
Related compounds Hydrazoic acid
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 YesY (verify) (what is: YesY/N?)
Infobox references

Lead azide (Pb(N3)2) is an inorganic compound. More so than other azides, Pb(N
3
)
2
is explosive. It is used in detonators to initiate secondary explosives. In a commercially usable form, it is a white to buff powder.

Preparation and handling[edit]

Lead azide is prepared by metathesis between sodium azide and lead nitrate. Dextrin can be added to the solution to stabilize the precipitated product. The solid is not very hygroscopic, and water does not reduce its impact sensitivity. It is normally shipped in a dextrinated solution that lowers its sensitivity. When protected from humidity, it is completely stable in storage.[5] An alternative method involves dissolving lead acetate in a sodium azide solution.[6][7]

Explosive characteristics[edit]

Lead azide is highly sensitive and usually handled and stored under water in insulated rubber containers. It will explode after a fall of around 150 mm (6 in) or in the presence of a static discharge of 7 millijoules. Its detonation velocity is around 5,180 m/s (17,000 ft/s).

Ammonium acetate and sodium dichromate are used to destroy small quantities of lead azide.

Lead azide reacts with copper, zinc, cadmium, or alloys containing these metals to form other azides. For example, copper azide is even more explosive and too sensitive to be used commercially.

Lead azide was a component of the six .22 caliber Devastator rounds fired from a Röhm RG-14 revolver by John Hinckley, Jr. in his assassination attempt on U.S. President Ronald Reagan on March 30, 1981. The rounds consisted of lead azide centers with lacquer-sealed aluminum tips designed to explode upon impact.[8]

See also[edit]

References[edit]

  1. ^ a b c d Pradyot, Patnaik (2003). Handbook of Inorganic Chemicals. The McGraw-Hill Companies, Inc. ISBN 0-07-049439-8. 
  2. ^ a b CID 61600 from PubChem
  3. ^ a b "Safety Data Sheet of Electronic Detonators, Division 1.4". http://www.ocsresponds.com. Owen Oil Tools LP. 2014-03-21. Retrieved 2014-06-09. 
  4. ^ Keller, J.J. (1978). Hazardous Materials Guide: Suppl, Issue 4. Abel Guerrero. 
  5. ^ Fedoroff, Basil T.; Henry A. Aaronson; Earl F. Reese; Oliver E. Sheffield; George D. Clift (1960). Encyclopedia of Explosives and Related Items (Vol. 1). US Army Research and Development Command TACOM, ARDEC. 
  6. ^ http://www.lambdasyn.org/synfiles/bleiazid.htm
  7. ^ Verneker, V. R. Pai; Forsyth, Arthur C. (1968). "Mechanism for controlling the reactivity of lead azide". The Journal of Physical Chemistry 72: 111. doi:10.1021/j100847a021. 
  8. ^ The Exploding Bullets, by Pete Barley and Charles Babcock, Washington Post, 4 Apr, 1981. Retrieved 28 February 2007.

External links[edit]